Lecture posters on the subject of materials science for a carpenter. Work program on the subject "Materials Science" by profession: "Master of joinery and furniture production". Adhesives and finishing materials

Ministry of Education of the Ryazan Region

Regional state budgetary education

Institution of secondary vocational education

"Kasimov technical school of water transport"

The work program of the academic discipline

OPD.03. Materials Science

Kasimov

2013

The work program of the academic discipline was developed on the basis of the Federal State Educational Standard (hereinafter - FSES) of the profession of primary vocational education (hereinafter NGO) 262023.01 "Master of joinery and furniture production".

APPROVED BY:

Director of OGBOU SPO "KTVT"

Shmelev A.V.

"__" __________ 2013

Developer:

Lartsin Alexander Nikolaevich, teacher of OGBOU NPO "KTVT" I qualification category

Agreed with the methodological commission of the disciplines of the general education cycle and professional modules

MC Minutes No. _____ dated "__" ________ 2013.

Chairman of the Commission _______ / Orlova O.V.

	PASSPORT OF THE WORKING PROGRAM OF THE DISCIPLINE
	STRUCTURE AND CONTENT OF THE EDUCATIONAL DISCIPLINE
	CONDITIONS FOR IMPLEMENTATION OF THE EDUCATIONAL DISCIPLINE
	CONTROL AND EVALUATION OF THE RESULTS OF THE LEARNING OF THE EDUCATIONAL DISCIPLINE

1. PASSPORT OF THE WORKING PROGRAM OF THE DISCIPLINE

"Materials Science"

1.1. SCOPE OF THE TRAINING PROGRAM

The working program of the discipline "Materials Science" is part of the main professional educational program in accordance with the Federal State Educational Standard for the profession NPO 262023.01 "Master of joinery and furniture production".

The working program of the discipline "Materials Science" can be used in additional professional education (in advanced training and retraining programs) and professional training of workers in the field of production of joinery and furniture products.

1.2. THE PLACE OF THE DISCIPLINE IN THE STRUCTURE OF THE BASIC PROFESSIONAL EDUCATIONAL PROGRAM: THE DISCIPLINE IS INCLUDED IN THE GENERAL PROFESSIONAL CYCLE.

1.3. PURPOSES AND OBJECTIVES OF THE DISCIPLINE - REQUIREMENTS FOR THE RESULTS OF THE DISCIPLINE DEVELOPMENT:

be able to :

select and use in work the main structural and auxiliary materials for the manufacture of joinery and furniture products;
determine wood species, sort wood by defects, rationally use it in the manufacture of joinery and furniture products;
store and dry timber and lumber;
select and use wood materials (veneer, plywood, chipboard and fiberboard) for the manufacture of joinery and furniture products;
select and use fasteners, fittings, fittings, glass products, mirrors and other auxiliary materials in work.

As a result of mastering the discipline, the student must

know :

constructional and auxiliary materials for the production of joinery and furniture products;
the structure of wood and wood, its physical, chemical, and mechanical properties, the specifics of application in the production of joinery and furniture products;
the main types of wood, their characteristics, flogging and grade of wood, the basics of forest commodity science;
rules for storage and drying of timber and lumber;
the specifics and range of wood materials, their area of application;
specifics and assortment of fasteners, fittings, fittings, glass products, mirrors, and other auxiliary materials.

1.4. NUMBER OF HOURS FOR LEARNING THE DISCIPLINE PROGRAM:

The maximum study load of a student is 84 hours, including:

Compulsory classroom teaching load of the student - 60 hours;

Student's independent work - 24 hours.

2. STRUCTURE AND CONTENT OF THE EDUCATIONAL DISCIPLINE

The volume of the discipline and types of educational work

Type of educational work	Qty Hour.

Compulsory classroom study load (total)
including:
Practical lessons
Student's independent work (total)
final examinationin the form of differential credit

2.2. THEMATIC PLAN AND CONTENT OF THE EDUCATIONAL DISCIPLINE "MATERIALS SCIENCE"

Name sections and topics	Laboratory and practical work, independent work of students	Volume hours	Development level

Section 1. Basic information about wood.
Topic 1.1. The structure of wood and wood

		The structure of the tree. Parts of a growing tree: roots, trunk, crown, their purpose
		Wood cuts: radial, tangential and transverse
		Macroscopic structure of wood. Trunk structure: bark, bast, cambium, sapwood, core and pith.
		Microscopic structure of wood: wood tissue and blood vessels cellular structure of wood
	Distinctive external features of radial, tangential, cross sections. The influence of wood structure on the quality of processing.
Section 2. Properties of wood
Topic 2.1. Physical properties of wood		Properties that determine the appearance and smell of wood
		Indicators of the macrostructure.
		Wood moisture content and properties associated with its change.
		Density of wood
		Thermal, electrical.
		Practical work
		Determination of the content of late wood in the annual layer.
		Determination of the equilibrium moisture content of wood.
Topic 2.2. Chemical properties of wood		Chemical composition of wood and bark, basic chemical reactions.
Topic 2.3. Mechanical and technological properties of wood		Mechanical properties of wood.
		The strength of the wood.
		The hardness of the wood.
		Technological properties of wood.
		Practical work
		Determination of the type of deformation according to the proposed samples.
	Independent work for students: Chemical composition of wood. Determination of macrostructure indicators Loads on wood products and structures.
Section 3. Wood defects and their influence on the physical and mechanical properties of wood
Topic 3.1 Wood defects
		Defects in the shape of the trunk: tightness, stiffness of growths, curvature.
		Defects in the structure of wood.
		Knots, their types and dimensions. Cracks. Types of cracks.
		Varieties of wood damage.
		Cutting defects. Warpedness of various shapes
		Practical work
		Determination of wood defects on samples (posters). Knots. Determination of wood defects on samples (posters). Defects in the structure of wood.
	Independent work for students: Characteristic differences between wood defects and defects Causes of defects in wood processing, warping and the appropriateness of its use in certain products.
Section 4. Characteristics of wood of the main species and their industrial application
Topic 4.1. Main types of wood
		The main macroscopic features of wood for the identification of species.
		Ring - vascular hardwood: oak, ash, elm, elm, karach.
		Scattered vascular deciduous species. Foreign rocks:
		Practical work
		Definition of conifers by their external characteristics. Determination of deciduous ring-vascular species by external signs. Determination of deciduous disseminated vascular species by external characteristics.
	Independent work for students: Characterization by macroscopic characteristics of various wood species with the justification of their use in joinery and furniture products
Section 5. Round forest materials
Topic 5.1. Lumber and blanks
		Timber classification, nominal dimensions, grades, allowances and tolerances; characteristics of timber.
		Practical work
		Measurement, accounting and marking of lumber and blanks.
	Independent work for students: Methods for obtaining forest products. Characteristics of round timber. Accounting, scoping and marking of round timber.
Section 6. Ensuring the durability of wood.
Topic 6.1. Storage, drying and wood protection		Wood storage The importance of proper storage of wood; ways to store it. Drying of wood.
		Wood preservative. Appointment. Protective equipment. Antiseptic solutions. Types of antiseptic compounds: water, oil, paste. Antiseptic methods. Painting, impregnation, coating, dry antiseptic treatment. Fire protection.
	Independent work for students: Advantages and disadvantages of wood drying methods. The need for wood anti-septation, conservation and fire protection. Methods of applying on the surface of wooden parts, structures, products of antesyptic and fire retardants.
Section 7. Wood based materials
Topic 7.1. Wood-leaf and slab materials
		Sliced and peeled veneer: production methods, types and applications. Characteristics of veneer, its production, grades, sizes. Plywood.
		Chipboard and fibreboard (Fiberboard), their types, manufacture, brands, main sheet dimensions, use in the manufacture of joinery and furniture production
		Blockboards and panels. Concept of joinery boards and boards.
		Practical work
		Determination of the type of sheet material by samples. Study of chipboard brands
	Independent work for students: Assortment of milled wood parts. Constructions of window, balcony, door blocks, window-sill boards, main standard sizes, types of finishes. Wood-aluminum windows, their designs and application
Section 8. Adhesives and paints and varnishes.
Topic 8.1. Adhesives.
		General information about adhesives. Types, groups, classification, basic properties, characteristics of adhesives and requirements for them. The concept of the adhesive, solvents and auxiliary materials (substances) that make up the adhesives, adhesion, viscosity, concentration of the adhesive solution, water resistance, pot life, biological resistance, hot and cold curing of adhesives. The appearance of adhesives.
Topic 8.2. paints and varnishes		Materials for surface preparation of wood and wood materials for finishing: primers, fillers, fillers.
		Film-forming agents and varnishes. Paints and enamels.
		Practical lessons
		Study of the main groups of adhesives. Study of materials for wood finishing.
		Examination of glutin and casein adhesives Preparation of the working composition of adhesives
	Independent work for students: Types, properties, storage rules, use of glue based on synthetic resins in joinery and furniture works. Adhesive films, tapes based on paper, synthetic resins and adhesives, their types, sizes, properties and applications.
Section 9. Film and sheet materials for facing joinery
Topic 9.1. Cladding materials
		Paper based film materials (transparent and opaque). General information about the manufacture of films from special paper.
		Polymer based film materials. Types of film materials. Facing sheet materials.
	Independent work for students: Production of films from special paper. Types, brands, properties, front surface of facing material, fastening methods. Types, properties based on polymers.
Section 10. Fittings and fasteners
Topic 10.1. Metal products and furniture fittings.
		Metal fasteners. Fasteners used in the production of joinery, glass and furniture works; nails: (carpentry, finishing, decorative, glass).
		Furniture fittings. Appointment and types of furniture fittings and furniture fasteners: ties, hinges. bolts. locks (mortise, mortise, overhead), holders, furniture handles, latches, brackets, products for functional equipment of cabinet furniture. Design, types of connecting products: squares, plates
		Practical work
		Study of the main metal fasteners and furniture fittings by samples.
		Differentiated credit.
		TOTAL

3. CONDITIONS FOR IMPLEMENTATION OF THE TRAINING DISCIPLINE

3.1. REQUIREMENTS FOR MINIMUM MATERIAL AND TECHNICAL SUPPORT

The implementation of the academic discipline requires the presence of a classroom "Materials Science"

Classroom equipment:

seats by the number of students;
teacher's workplace;
a set of teaching aids "Materials Science";
standard samples of wood of various species, macro and microstructure of wood;
albums with wood flaws;
samples of wood of various species;
samples of wooden products;
samples of adhesive films and tapes;
samples of basic metal fasteners and furniture fittings.

Technical training aids:

a computer.

3.2. INFORMATION SUPPORT OF TRAINING.

Main literature:

Stepanov B.A. Materials science for professions related to wood processing textbook: for the beginning. prof. education. - M .: Publishing Center "Academy", 2009.-328s.

Additional literature:

Stepanov B.A. Handbook of the carpenter and joiner: textbook. manual for the beginning. prof. education. - M .: Publishing Center "Academy", 2010.-304s.
Reference book Master of joinery and furniture production: textbook. manual for the beginning. prof. education. - M .: Publishing Center "Academy", 2010.-304s.
G.I. Klyuev Joiner (basic level): textbook. allowance. - M .: Publishing Center "Academy", 2007.-80s.

4. CONTROL AND EVALUATION OF THE RESULTS OF THE LEARNING OF THE EDUCATIONAL DISCIPLINE

Control and assessment of the results of mastering the academic discipline is carried out by the teacher in the process of conducting practical classes and laboratory work, testing, as well as the implementation of individual lessons, projects, research by students.

Learning outcomes (learned skills, learned knowledge)	Forms and methods of monitoring and evaluating learning outcomes
Skills:
Describe the structure of wood of various species, macro- and microstructure of wood. Determine the defects in the shape of the trunk, the structure of wood, chemical colors and biological damage	Practical lessons Testing
Determine the density, moisture content of wood samples to compare with the standard	Practical lessons
Determine the mechanical properties of wood of various species using standard samples	Practical lessons
Determine wood species by external signs and properties
Distinguish adhesives by their appearance and prepare a working composition of adhesives	Practical lessons Testing
Distinguish between metal fasteners and furniture fittings by samples	Practical lessons
Knowledge :
on the purpose of parts of the tree; to characterize sections of wood according to samples, to outline the distinctive external features of radial, tangential, cross sections.	Practical lessons Testing
about the properties that determine the appearance of wood; types of moisture in wood	Independent work
about the mechanical and technological properties of wood	Extracurricular independent work
About methods of wood preservative, wood preservation and fire protection	Practical lessons Testing
About types of forest materials and lumber	Practical lessons
About the technology of production of veneer, plywood, plywood chipboard and fiberboard, their types, sizes, grades.	Extracurricular independent work
basic information about adhesives, paints and varnishes, purpose and properties.	Practical exercises, extracurricular independent work
basic information about metal products and furniture fittings	Practical lessons

Introduction 3
Section one. Fundamentals of Wood Science 5
Chapter I. The structure of wood and timber 5
§ 1. The structure of a tree 5
§ 2. Macroscopic structure of wood 6
§ 3. Microscopic structure of wood 9
Chapter II. Physical and chemical properties of wood 12
§ 4. Properties that determine the appearance of wood 12
§ 5. Wood moisture and properties associated with its change 14
§ 6. Density of wood 17
§ 7. Thermal conductivity, sound conductivity, electrical conductivity of wood 18
§ 8. Chemical structure and use of wood 19
Chapter III. Mechanical properties of wood 20
§ 9. Durability of wood 20
§ 10. Hardness, deformability and impact strength of wood 21
§ 11. Technological properties of wood 22
Chapter IV. Vices of wood 23
§ 12. Knots 23
§ 13. Cracks 26
Section 14. Defects in the shape of the trunk 28
Section 15. Defects in the structure of wood 29
§ 16. Chemical colors. ... ... , .... 34
§ 17. Fungal lesions. , 34
§ 18. Biological damage. ... ... ... .... ... ... 36
§ 19. Foreign inclusions, mechanical damage and processing defects 37
§ 20. Warped ™. ... ... ... ... ; ... ......... ... , -. ... ... ... 39
Chapter V. Characteristics of the main timber before- And "their industrial value 40
Section 21. The main macroscopic characteristics of wood for the determination of species 40
Section 22. Conifers 40
Section 23. Hardwoods 43
Section 24. Foreign rocks 47
Section two. Forestry 48
Chapter VI. Classification and standardization of forest products 48
Section 25. Classification of forest products 48
Section 26. Characteristics of round timber 49
Section 27. Measurement, accounting and marking of round timber 51
Section 28. Storage of round timber 52
Chapter VII. Lumber and billets 53
Section 29. Characteristics of sawn timber 53
Section 30. Sawn softwood and hardwood 55
Section 31. Blanks 57
Section 32. Measurement, accounting and marking of sawn timber and blanks 62
Chapter VIII. Methods for storing and extending the life of wood 62
Section 33. Storage and atmospheric drying of wood 63
Section 34. Protection of wood from rotting and destruction by insects 64
Section 35. Fire protection of wood 65
Chapter IX. Veneer, plywood, wood-based panels and plastics 66
Section 36. Sliced and peeled veneer 66
Section 37. Plywood 67
Section 38. Plywood for special purposes 68
Section 39. Plywood boards 70
Section 40. Blockboards 71
Section 41. Fiber boards 72
Section 42. Chipboards 73
143

Section three. Adhesives and finishing materials 75
Chapter X. Adhesives 75
§ 43. Types, composition and basic properties of adhesives 75
§ 44. Glutin adhesives "77
Section 45. Casein glues 78
Section 46. Synthetic adhesives 79
Chapter XI. Materials for preparing the surface of joinery for finishing 8-5
Section 47. Grinding (abrasive) materials 85
§ 48. Primers, fillers, putties and putties 88
Section 49. Resin vaccination and bleaching compositions 91
Chapter XII. Paints and varnishes 91
§ 50. Dyes, fillers, solvents, thinners, plasticizers ... 92
Section 51. Film-forming substances 94
Section 52. Varnishes and varnishes 96
Section 53. Paints and enamels 99
§ 54. Refinement of paint and varnish coatings 102
Chapter XIII. Film and sheet finishing materials 104
Section 55. Film and sheet materials based on paper 104
§ 56. Films made of synthetic resins 105
§ 57. Decorative laminates 105
Section four. Materials and products for construction 107
Chapter XIV. Materials and products for floors 107
§ 58. Parquet, parquet boards and boards 107
§59. Polymeric materials for floors PO
§ 60. Mastics P2
Chapter XV. Construction, facing and roofing materials for construction. ... ... 114
§61. Materials of construction and details 114
Section 62. Roofing materials 118
§ 63. Facing materials. 123
Chapter XVI. Metal products and furniture fittings 126
Section 64. Metal fasteners 126
§ 65. Devices and products for windows and doors 127
§ 66. Furniture fittings 131
Section 67. Glass and mirrors 136
Chapter XVII. Insulating and Lubricating Materials 138
Section 68. Insulating materials 138
Section 69. Electrical insulating materials 139
Section 70. Lubricants 140
Recommended reading 142

Branch of the state budgetary professional

educational institution of the Yamalo-Nenets Autonomous Okrug

"Yamal Multidisciplinary College" in Labytnangi

(branch of GBPOU YANAO "YAMK" in Labytnangi)

Considered:

MO "Builder"

protocol no. 5

Approved by

Methodical advice

protocol No. __________

dated _____________2015

Materials (edit)

for differential credit

on the academic discipline "Materials Science"

by profession 18880 "Construction joiner"

2015

Explanatory note

The test material for differentiated credits was compiled on the basis of the Federal State Educational Standard (FSES) for the profession SPO 18880 "Construction joiner" and in accordance with the requirements for the knowledge and skills of students in the discipline "Materials Science" stated in the Work Program.

The purpose of the differentiated offset- carrying out the final certification of students in the discipline for the course of study.

The subject of the discipline "Materials Science" is a system of knowledge about the rational and integrated use of wood through processing into useful and valuable products without any losses and waste in the process of labor activity. The existing structure of timber harvesting, an increase in the cost of transportation from harvesting sites to consumption sites, make the issue of saving and rational use of wood very important.

Experience shows that in order to produce high-quality products and perform work, a joiner, carpenter, glazier, parquet flooring, woodworker requires good knowledge of work technology, product design and material properties. The methods and modes of processing, the quality of the manufactured products, their appearance, strength, durability and cost depend on the type and properties of the materials used. The structure of technological equipment and tools, the labor intensity of work and the duration of the production cycle, the level of possible mechanization, working conditions and the necessary qualifications of workers depend on the materials. The solution to this important task is possible only by qualified craftsmen with all the necessary knowledge.

In market conditions, vocational education is faced with the acute issue of training professional personnel who can easily adapt to changing production conditions. At the current level of construction, it is impossible to become an experienced woodworker without systematic advanced training, without studying advanced technology, types of modern materials and labor organization. The task of open source software is to educate in the future young worker certain skills and abilities, so that he becomes an active builder, a zealous owner with the inherent working class - morality, interests, collectivist psychology, high culture of work, behavior, life.

The purpose of the implementation of this program is to provide knowledge of the main types of wood, their properties, structural features, defects, methods of storage, drying, antiseptic and fire protection, a number of concepts of the discipline "Materials Science".

The course "Materials Science" includes overview topics and graphic, the combination of which makes it possible not only to acquaint students with a number of possible concepts of wood science, but also to connect with practice.

activation of methods of mental activity: generalization, systematization, comparison;

revealing the depth of knowledge of factual material.

The test material consists of 25 test items of part A and 10 test items of part B, compiled in two versions and includes questions on the main sections of the discipline:

The structure of wood and timber.

Defects of wood.

Round timber, lumber, blanks and products.

The time to complete this test is 1 academic hour.

Evaluation criteria:

35-33 points - "5";

32-30 points - "4";

29-27 points - "3";

less than 27 points - "2".

SPE specialty: 18880 "Construction joiner"

VD 01. Materials Science

Specification of didactic units

p / p

Name of didactic units

The structure of wood and timber.

Physical properties of wood.

Mechanical properties of wood.

Defects of wood.

Characterization of the main wood species and their industrial use.

Veneer, plywood, wood-based panels, parquet.

Adhesives, their types, composition and properties.

Materials for preparing the surface of joinery for finishing.

Materials and products for floors. Construction materials.

Cladding, insulation and roofing materials for construction.

Test item codifications

P / p No.

Name of the didactic unit

Option number

Question numbers

The structure of wood and timber.

1,2,3,4,5,6, 26,27,28,29

1,2,3,4,5,6, 26,27,28

Physical properties of wood.

7,8,9,10,30, 31

7,8,9,10,29

Mechanical properties of wood.

11,12

11,12,30

Defects of wood.

13,14,15,16,17,32,33,34

13,14,15,16,17,31,32,33

Characterization of the main wood species and their industrial use.

18,19

18,19,34

Round timber, lumber, billets and products.

20,35

Veneer, plywood, wood-based panels, parquet.

21,35

Adhesives, their types, composition and properties.

Materials for preparing the surface of joinery for finishing.

Materials and products for floors. Construction materials.

Cladding, insulation and roofing materials for construction.

NGO specialty: 18880 "Construction joiner"

Curriculum section: General professional cycle

VD 01. Materials Science

Option number 1

Block A

P / p No.

Assignment (question)

Reference

the answer

Instructions for completing tasks number 1-25: select the letter corresponding to the correct answer and write it down in the answer form. For example:

№ tasks

Possible answer

1-B

Choose the correct answer:

A). Root;

B). Barrel;

B). Crown;

D).

Choose the correct answer:

A). Cambium;

B) .shell;

B). Cork;

D) deep.

Choose the correct answer:

A cut perpendicular to the transverse section through the core of the barrel?

A). Transverse;

B) .radial;

B). Tangential;

D). Longitudinal.

Choose the correct answer:

In a growing tree, does it act as a conductor of water from roots to leaves?

A). resin passages;

B). cambium;

B). Kernel;

G). sapwood.

Choose the correct answer:

A). Late;

B). Early;

B) .year;

D) .spring.

Choose the correct answer:

Are tissue stores and stores of nutrients?

A) .mechanical;

B) .cover;

B). Support;

D). Storing.

Choose the correct answer:

The pattern on the surfaces of the cuts, which is obtained when cutting wood fibers, annual layers and core rays?

A). Macrostructure;

B). Texture;

B). Structure;

D). Drawing.

Choose the correct answer and continue the sentence:

What is the moisture content of wood that has been in water for a long time?

A). Air dry;

B). Indoor-dry;

B). Freshly cut;

D). Wet.

Choose the correct answer:

A). Cracking;

B). Drying;

B). Swelling;

D). Boxing.

Choose the correct answer:

The ability of wood to directionally reflect the luminous flux?

A). Smell;

B). Texture;

B). Shine;

D). Color.

Choose the correct answer:

The ability of a material to resist the penetration of solids into it?

A). Hardness;

B). Density;

C). Strength;

D). Deformation.

Choose the correct answer:

The ability of wood to resist wear and tear, i.e. destruction in the process of friction?

A). Deformability;

B). The ability to bend;

B). Splitting;

D). Wear resistance.

Choose the correct answer:

A). Consistency;

B). Escapism;

B). Curvature;

D) .roll.

Choose the correct answer:

A) .memetic;

B). Drying;

B). Stunning;

D). Frosty.

Choose the correct answer:

Deep marks left on the surface of the wood by the working bodies of the cutting tool?

A). Scratches;

B). Risks;

B). Fuzziness;

D). Dent.

Mycelium and fruiting of molds on raw sapwood, with improper storage of timber?

A). Zabolic rot;

B). Drilling;

B). Kernel rot;

D). Mold.

A). Wingedness;

B). Submissiveness;

B). Boxing;

D). Oblique.

B). Conifers;

D) .interrestrial.

Does hardwood turn gray after being in water for a long time?

A). Alder;

B). Stained oak;

B). Gray birch;

D). Clip.

Products that are machined mainly from the trunk of a tree?

A). Lumber;

B) timber materials;

B) preparation;

B). Assortments.

A). Fiberboard;

B). Chipboard;

B). Plywood;

D). Veneer;

A glue made from raw hides and leather waste?

A). Glutinous;

B) .bone;

B). Casein;

D). Onerous.

Paints and varnishes that level the surface before applying opaque coatings to them?

A) .Pore placeholders;

B). Primers;

B) putties;

D). Polish.

Roll material for flooring?

A). Linoleum;

B). Roofing material;

B). Pergamine;

D). Only.

A cladding material made of gypsum binder and cardboard, intended for cladding walls and partitions?

A). Paper-laminated plastic;

B). Drywall;

B) cement-bonded particle boards;

D). Laminated panels.

Block B

P / p No.

Assignment (question)

Reference

the answer

root

bast

A dark-colored part of the trunk that performs a mechanical function in a growing tree?

core

early

Is the pattern on the surfaces of the sections determined by the width of the annual layer, the direction of the fibers?

texture

Colour

stunning

scratches

warpedness

lumber

NGO specialty: 18880 "Construction joiner"

Curriculum section: General professional cycle

OP 04. Construction Economics Fundamentals

Option number 2

Block A

P / p No.

Assignment (question)

Reference

the answer

Instructions for completing tasks number 1-25: Select the letter corresponding to the correct answer and write it down in the answer form.

For example:

№ tasks

Possible answer

1-B

Choose the correct answer:

The lower part of the trunk, accounting for 15% of the total mass of the tree?

A). Root;

B). Barrel;

B). Crown;

D).

Choose the correct answer:

A layer of bark that conducts water with organic matter produced in leaves or needles down the trunk?

A). Cambium;

B) .shell;

B). Cork;

D) deep.

Choose the correct answer:

A cut at some distance from the core?

A). transverse;

B). radial;

V). tangential;

G). longitudinal.

Choose the correct answer:

A dark-colored part of the trunk that performs a mechanical function in a growing tree?

A) resin passages;

B). Cambium;

B). Kernel;

D) sapwood.

Choose the correct answer:

Light colored wood, formed in spring and early summer?

A). Late;

B). Early;

B) .year;

D) .spring.

Choose the correct answer:

Are the fabrics in the bark that protect the wood from external influences?

A) .mechanical;

B) .cover;

B). Support;

D). Storing.

Choose the correct answer:

Pattern on the surfaces of the sections, determined by the width of the annual layer, the direction of the fibers, etc.?

A). Macrostructure;

B). Texture;

B). Structure;

D). Drawing.

Choose the correct answer:

The moisture content of wood exposed to air for a long time?

A). Air dry;

B). Indoor-dry;

B). Freshly cut;

D). Wet.

Choose the correct answer:

Reduction of linear dimensions and volume of wood when it dries?

A). Cracking;

B). Drying;

B). Swelling;

D). Boxing.

Choose the correct answer:

The property of wood, determined by the presence of tannins, resinous and dyes in it?

A). Smell;

B). Texture;

B). Shine;

D). Color.

Choose the correct answer:

The ability of a material to resist fracture from stress arising under the action of a load?

A). Hardness;

B). Density;

C). Strength;

D). Deformation.

Choose the correct answer:

Changes in shape and size of wood under the influence of loads or other factors?

A). Deformability;

B). The ability to bend;

B). Splitting;

D). Wear resistance.

Choose the correct answer:

A sharp increase in the diameter of the butt of the timber or the width of unedged timber?

A). Consistency;

B). Escapism;

B). Curvature;

D). The slope of the fibers.

Choose the correct answer:

Cracks in the core, passing between the annual layers and having a significant length along the length of the timber?

A) .memetic;

B). Drying;

B). Stunning;

D). Frosty.

Choose the correct answer:

Damage to the surface of the timber with a sharp object in the form of a narrow, long damage?

A). Scratches;

B). Risks;

B). Fuzziness;

D). Dent.

Bases of branches enclosed in wood, the most common defect in wood?

A). Cracks;

B). Knots;

B) .brow;

D). Step-son.

Curvature of lumber when sawing, drying or storing?

A). Wingedness;

B). Submissiveness;

B). Boxing;

D). Oblique.

Woods that have a turpentine smell and resin passages are visible on almost all of them?

A). Deciduous ring-vascular;

B). Deciduous disseminated vascular;

B). Conifers;

D) .interrestrial.

Deciduous wood, after a long (decade) stay in water, acquiring a dark brown or black color?

A). Alder;

B). Stained oak;

B). Gray birch;

D). Clip.

Materials obtained from longitudinal sawing of logs and logs of a certain size and quality?

A). Lumber;

B) timber materials;

B) preparation;

B). Assortments.

Hot-pressed or wood-fiber-dried sheeting formed into a carpet?

A). Fiberboard;

B). Chipboard;

B). Plywood;

D). Veneer;

Is it a glue that contains milk protein?

A). Glutinous;

B) .bone;

B). Casein;

D). Onerous.

Compounds intended to be rubbed into the pores of wood in order to seal them before applying clear coatings?

A) .Pore placeholders;

B). Primers;

B) putties;

D). Polish.

A kind of profile molded products (vinyl lining)?

A). Metal tile;

B). Siding;

B). Organic glass;

D). Ondulin.

Galvanized steel sheet roofing material?

A). Gont;

B). Asbestos-cement corrugated sheets;

B). Ondulin;

D). Metal tile.

Block B

P / p No.

Assignment (question)

Reference

the answer

Instructions for completing tasks No. 26-35: in the appropriate line of the answer sheet, write down the short answer to the question, the end of the sentence or the missing words.

The top of the trunk, making up 12% of the total mass of the tree?

crown

A layer of bark that protects the trunk wood from sudden temperature changes, mechanical damage, and other external influences?

suberic

Does wood facing the bark grow in late summer and early fall?

late

Increase in linear dimensions and volume of wood with increasing moisture content?

swelling

The ability of wood to resist wear, i.e. destruction in the process of friction?

wear resistance-bone

Changing the diameter of the trunk along the length of the tree, a gradual decrease in the diameter of the tree from the butt to the top?

contiguity

Radially directed cracks that occur in a felled tree under the influence of internal stresses during the drying process?

shrinkage

Spiral (helical) curvature of the lumber along the length?

wingedness

Trees with no visible core rays and different annual layers across all sections?

conifers

Laminated sheet material, usually with an odd number of layers?

Introduction 3
BASIC WOOD SCIENCE 4
1. The structure of wood and wood 4
§ 1. The structure of a tree 4
§ 2. Macroscopic structure of wood 6
§ 3. Microscopic structure of wood 10

2. Physical properties of wood 14
§ 5. Wood moisture and properties associated with its change 16
§ 6. Density of wood
§ 7. Thermal conductivity, sound conductivity, electrical conductivity of wood 21

3. Mechanical properties of wood
§ 8. General concepts of mechanical properties and testing of wood 21
§ 9. Durability of wood
§ 10. Hardness, deformability and impact strength of wood 23
§ 11. Technological properties of wood 24

4. Vices of wood 25
§ 12. Knots 26
§ 13. Cracks 29
Section 14. Defects of the shape of the trunk 32
Section 15. Defects in the structure of wood 33
§ 16. Chemical colors 39
§ 17. Fungal lesions 39
Section 18. Damage to wood by insects 43
§ 19. Foreign inclusions and defects 44
Section 20. Deformation of wood 46

5. Characteristics of the main wood species and their industrial value 46
Section 21. The main macroscopic characteristics of wood for the determination of species 46
Section 22. Conifers 47
Section 23. Hardwood 49
Section 24. Foreign tree species 55

ADHESIVES AND FINISHING MATERIALS 57

6. Adhesives 57
§ 25. Types, composition and basic properties of adhesives 57
Section 26. Adhesives of animal origin 59
Section 27. Casein glues 62
Section 28. Synthetic adhesives 63

7. Paints and varnishes and other finishing materials
Section 29. Dyes, fillers, solvents, thinners, plasticizers 68
Section 30. Film-forming substances 71
§ 31. Primers, fillers, putties and putties 73
Section 32. Varnishes and varnishes 76
Section 33. Paints and enamels 81

8 Film and sheet finishing materials 8E
Section 34. Film and sheet materials based on paper 85
Section 35. Films made of synthetic resins 86
Section 36. Decorative laminates 87

9. Supporting materials 88
Section 37. Grinding materials
Section 38. Polishing, degumming and bleaching compounds 90

FORESTRY PRODUCTION 93

10. Classification and standardization of forest products 93
11. Round timber 94
Section 39. Characteristics of round timber 94
Section 40. Measurement, accounting and marking of round timber 96
Section 41. Storage of round timber 99

12. Lumber and billets 99
Section 42. Characteristics of sawn timber 99
Section 43. Sawn softwood and hardwood 102
§ 44. Blanks § 45. Measurement, accounting and marking of sawn timber and blanks 105

13. Ways to extend the life of wood 107
Section 46. Storage and atmospheric drying of wood
Section 47. Protection of wood from rotting and destruction by insects 109
Section 48. Fire protection of wood 112

14. Veneer, plywood and wood-based panels 113
§ 49. Sliced and peeled veneer FROM
Section 50. Plain plywood 115
Section 51. Plywood for special purposes 116
Section 52. Plywood boards 118
Section 53. Bent glued blanks 118
Section 54. Blockboards
Section 55. Fiber boards 120
Section 56. Particle boards 123

15. Materials and products for construction 125
§ 57 Window and balcony blocks 125
§ 58 Door blocks 129
§ 59. Materials and products for floors 132
Section 60. Wooden milled and molded parts for construction 139
Section 61. Roofing and other materials 143

16. Metal products and furniture fittings 147
§ 62. Brief information about metals and alloys 147
Section 63. Metal fasteners 150
§ 64. Appliances and products for windows and doors 152
§ 65. Furniture fittings 157
Section 66. Glass and mirrors 164

17. Insulating, fastening and lubricating materials 166
§ 67. Insulating materials and mastics 166
Section 68. Electrical insulating materials 168
§ 69. Lubricants 169
Literature 170

The book contains information about the structure, physical and mechanical properties, defects of wood and their influence on its quality, gives a classification and distinctive features of coniferous and deciduous wood. The classification and characteristics of round timber, sawn timber and blanks, sliced and peeled veneer, plywood, wood-based panels, as well as wooden parts and products for construction are given.

Introduction

It is difficult to name any branch of the national economy where wood would not be used in one form or another (natural or processed), and to list all the various products in which wood is a constituent part. In terms of the volume of use and the variety of applications in the national economy, no other material can be compared with wood.
The widespread use of wood is facilitated by its high physical and mechanical properties, good workability, as well as effective methods of changing certain properties of wood by chemical and mechanical treatment. Wood is easy to process, has low thermal conductivity, sufficiently high strength, good resistance to shock and vibration loads, and is durable in a dry environment. The positive properties of wood are the ability to adhere firmly, maintain a beautiful appearance and perceive the finish well. At the same time, wood has disadvantages: it is susceptible to burning and decay, is destroyed by the effects of insects and fungi, is hygroscopic, as a result of which it can swell and undergo shrinkage, warping and cracking. In addition, wood has biological defects that reduce its quality.
In the manufacture of wood products, adhesives, paints and varnishes, finishing films, plastics, accessories and other materials play an important role.
Peeled and planed veneers are widely used in the manufacture of joinery - the starting materials for the production of various semi-finished products. Glued laminated wood is made from peeled veneer - plywood, plywood boards, glued furniture parts, parts of TV and radio casings, containers. Sliced veneer is the main facing material for parts made of low-value wood, plywood and particle boards.
The methods and modes of processing, the quality of the manufactured products, their appearance, strength, durability, and cost depend on the type and properties of the materials used.
Unlike oil, coal and gas, wood is a renewable natural resource. However, this does not exclude the need for careful and rational use of it. Advances in science, especially chemistry, and excellence are the basis for the use of wood - this gift of living nature. The rational use of forests is an important part of the general problem of nature protection, the state significance of which was emphasized in the Resolution of the Supreme Soviet of the USSR dated September 20, 1972 "On measures to further improve nature protection and the rational use of natural resources." Article 67 of the Constitution (Basic Law) of the Union of Soviet Socialist Republics reads: "Citizens of the USSR are obliged to protect nature, to protect its wealth." The protection of forest resources is easy to explain: forests have a beneficial effect on the country's climate, create good working and rest conditions for people, for the development of agriculture. Massive deforestation leads to the formation of deserts, soil erosion, shallowing of rivers, the emergence of dry winds and a sharp decrease in productivity. Forest is our national wealth, it must be spent with care, with the greatest return.In the tenth five-year plan, due to the deepening of raw materials processing, the expansion of the technological use of waste and low-quality wood, the economy of commercial wood should amount to more than 40 million m3. It is a matter of honor for every joiner and carpenter, every logger and woodworker to make a contribution to the fulfillment of this important national economic task.

FUNDAMENTALS OF WOOD SCIENCE
1. The structure of wood and wood
§ 1. The structure of a tree
Parts of a growing tree. A growing tree consists of a crown, trunk and roots (Fig. 1). During the life of a tree, each of these parts performs its own specific functions and has various industrial applications.
The crown consists of branches and leaves (or needles). From carbon dioxide absorbed from the air and water obtained from the soil, complex organic substances are formed in the leaves, which are necessary for the life of the tree. The industrial use of the crown is small. From the leaves (needles), vitamin flour is obtained - a valuable product for livestock and poultry farming, medicines, from the branches - a technological shepa for the production of containerboard and fiberboard.
The trunk of a growing tree conducts water with dissolved minerals upward (upward current), and with organic substances downward to the roots (downward current); stores spare nutrients; serves to accommodate and maintain the crown. It gives the bulk of wood (from 50 to 90% of the volume of the whole tree) and is of major industrial importance. The upper thin part of the trunk is called the apex, the lower thick part is the butt.
In fig. 1b shows the process of development of a coniferous tree from seed and a diagram of the construction of a tree trunk at the age of 13 years. The growth process can be thought of as the build-up of cone-shaped layers of wood. Each last cone has a great height and base diameter. The figure shows 10 concentric circles (boundaries of annual increments) on the lower cross section, and on the same upper section there are only five of them. Consequently, it takes 3 and 8 years, respectively, for the tree to reach the height at which the lower and upper cross-sections were made.
The roots carry the water with the minerals dissolved in it up the trunk; store nutrient stores and keep the tree upright. The roots are used as a second-rate fuel. The stumps and large roots of the pine, some time after the felling of the trees, serve as raw materials for obtaining rosin and turpentine.
Main trunk cuts. The section running perpendicular to the axis of the trunk forms an end plane, the section passing through the core of the trunk forms a radial plane, and at some distance from it - a tangential plane (Fig. 2). The wood in these sections has a different look and unequal properties.
On the cross-section of the trunk (Fig. 3), you can see the core, bark and wood with its annual layers.
The bark covers the tree with a continuous ring and consists of a layer - a crust and an inner layer - bast 5, which conducts water with organic matter produced in the leaves down the trunk. The bark protects the tree from mechanical damage, sudden temperature changes, insects and other harmful environmental influences.
The type and color of the bark depends on the age and species of the tree. Young trees have a smooth bark, and with age, cracks appear in the bark. The bark can be smooth (fir), scaly (pine), fibrous (juniper), warty (euonymus). The color of the bark has many shades, for example, white for birch, dark gray for oak, dark brown for spruce.
Rice. 3. Cross section of the trunk:
7 - core 2 - core rays 3 - core. 4 - cork syu, 5 - bast layer 6 - sapwood. 7 - cambium. 8 - annual layers
Depending on the species, the age of the tree and the growing conditions in our forest species, the bark makes up from 6 to 25% of the trunk volume. The bark of many tree species is of great practical use. It is used for tanning leather, making floats, corks, insulation and building boards. From the bast of the bark, bast, matting, ropes, etc. are made. Chemicals used in medicine are extracted from the bark. Birch bark serves as a raw material for tar production. Between the bark and the wood, there is a very thin, juicy layer that is not visible to the naked eye - the cambium, consisting of living cells.
The timber in the growing tree — occupies a large portion of the trunk and is of major industrial importance.
The terms and definitions of the basic concepts related to the structure and physical and mechanical properties of wood are established by GOST 23431-79.
§ 2. Macroscopic structure of wood
Sapwood, kernel, ripe wood
The wood of our forest species is usually light colored. At the same time, in some species, the entire mass of wood is painted in one color (alder, birch, hornbeam), in others, the central part has a darker color (oak, larch, pine). The dark-colored part of the trunk is called the core, and the light peripheral part is called sapwood.
In the case when the central part of the trunk has a lower water content, that is, it is drier, it is called ripe wood, and the species is called ripe wood. Rocks with a core are called sound. The rest of the rocks, which do not differ between the central and peripheral parts of the trunk, either in color or in water content, are called sapwood (without kernels).
Of the tree species growing on the territory of the Soviet Union, the core is: conifers - pine, larch, cedar; deciduous - oak, ash, elm, poplar. Ripe woody species are coniferous spruce and fir, deciduous beech and aspen. Sapwood species include deciduous: birch, maple, hornbeam, boxwood.
However, in some non-nucleated species (birch, beech, aspen), a darkening of the central part of the trunk is observed. In this case, the dark central area is called a pseudo-nucleus.
Young trees of all species do not have a core and are composed of sapwood. Only over time is the core formed due to the transition of sapwood to heartwood.
The nucleus is formed due to the death of living wood cells, blockage of waterways, deposits of tannins, dyes, resin, calcium carbonate. As a result, the color of the wood, its weight and indicators of mechanical properties change. The width of the sapwood varies depending on the breed, growing conditions. In some species, the nucleus is formed in the third year (yew, white acacia), in others - in the 30-35th year (pine). Therefore, the sapwood is narrow in the gis, and in the pine it is wide.
The transition from sapwood to the kernel can be abrupt (larch, yew) or smooth (walnut, cedar). In a growing tree, sapwood is used to carry water with minerals from the roots to the leaves, and the core performs a mechanical function. Sapwood wood easily permeates water, is less resistant to decay, therefore, when making containers for liquid goods, sapwood should be used limitedly.
Annual layers, early and late wood
The cross section shows concentric layers around the core. These formations represent the annual growth of wood. They are called annual layers. On the radial section, the annual layers have the form of longitudinal stripes, on the tangential section - winding lines (Fig. 4). Annual layers grow annually from the center to the periphery, and the outermost layer is the youngest. The age of the tree can be determined by the number of annual layers on the butt end section.
The width of the annual layers depends on the breed, growth conditions, position in the trunk. In some (fast-growing) breeds, the annual layers are wide (poplar, willow), in others - narrow (boxwood, yew). In the lower part of the trunk, the narrowest annual layers are located, up the trunk the width of the layers increases, since the growth of the tree occurs both in thickness and in height, which brings the shape of the trunk closer to the cylinder.
In the same breed, the width of the annual layers may be different. Under unfavorable growth conditions (drought, frost, lack of nutrients, waterlogged soils), narrow annual layers are formed.
Sometimes, on two opposite sides of the trunk, the annual layers have an unequal width. For example, in trees growing at the edge of a forest, on the side facing the light, the annual layers are wider. As a result, the pith of such trees is displaced to the side and the trunk has an eccentric structure.
Some breeds are characterized by an irregular shape of the annual layers. So, on the cross-section of hornbeam, yew, juniper, waviness of annual layers is observed.
Each annual layer consists of two parts - early and late wood: early wood (inner) facing the heart, light and soft; late wood (outer) is bark-facing, dark and hard. The difference between early and late wood is clearly expressed in conifers and some leaves.
Rice. S. View of the pith rays on the transverse (a), tangential (b), radial (c) sections of wood
vein rocks. Early wood is formed in early summer and serves to carry water up the trunk; late wood is deposited towards the end of summer and performs mainly a mechanical function. Its density and mechanical properties depend on the amount of late wood.
Core beams, core repetitions
In the cross section of some rocks, light, often shiny, lines directed from the core to the bark — the core rays — are clearly visible with the naked eye (Fig. 5). Core rays are present in all breeds, but are visible only in some.
In width, the core rays can be very narrow, not visible to the naked eye (in boxwood, birch, aspen, pear and all conifers); narrow, difficult to distinguish (in maple, elm, elm, linden); wide, well visible with the naked eye in cross section. Wide rays are real wide (in oak, beech) and false-wide - bundles of close narrow rays (in hornbeam, alder, hazel).
On a radial section, the pith rays are visible in the form of light shiny stripes or ribbons located across the fibers. The core rays can be lighter or darker than the surrounding wood.
On a tangential section, they are visible in the form of dark streaks with pointed ends or in the form of lenticular stripes placed along the fibers. “The width of the rays ranges from 0.015 to 0.6 mm.
The core beams in the felled wood create a beautiful pattern (on a radial cut), which is important when choosing wood as a decorative material.
In a growing tree, the core rays serve to conduct water in a horizontal direction and to store reserve nutrients.
The number of pith rays depends on the breed: in deciduous species, pith rays are about 2-3 times more painful than in conifers.
On the end section of some wood species, you can see scattered dark specks of brown, brown color, located closer to the border
annual layer. These formations are called core repetitions. The core repetitions are formed as a result of damage to the cambium by insects or frost and resemble the core in color.
Vessels
On the transverse (end) section of hardwood, openings are visible, representing the sections of vessels - pipes, channels of different sizes, intended for conducting water. By their size, the vessels are divided into large, well visible with the naked eye, and small, invisible to the naked eye.
Large vessels are most often located in the early wood of the annual layers and form a continuous ring of vessels in cross-section. Such hardwoods are called annular. In ring-vascular rocks in late wood, small vessels are collected in groups, clearly visible due to their light coloration. If small and large vessels are evenly distributed over the entire width of the annual layer, then such breeds are called diffuse vascular deciduous species.
In ring-vascular deciduous trees, the annual layers are clearly visible due to the sharp difference between early and late wood. In deciduous disseminated vascular species, such a difference between early and late wood is not observed, and therefore the annual layers are poorly visible.
In deciduous ring-vascular species, small vessels in late wood form the following types of groupings: radial - in the form of light radial stripes resembling tongues of flame (Fig. 6, a - oak, chestnut); tangential - small vessels form light solid or discontinuous wavy lines elongated along the annual layers (Fig. 6, b - elm, elm, elm); scattered - small vessels in late wood are located in the form of light dots or lines (Fig. 6, c - ash).
In fig. 6, d shows the location of the vessels in a deciduous disseminated vascular breed (walnut). Vessels are evenly distributed over the entire width of the annual layer.
On the radial and tangential sections, the vessels look like longitudinal grooves. The volume of vessels, depending on the breed, ranges from 7 to 43%.
Resin passages
A characteristic feature of the structure of coniferous wood is resin passages. Distinguish between vertical and horizontal resin passages. The horizontal ones pass along the core beams. Vertical resin passages are thin, narrow channels filled with resin. Cross-section
Rice. 6. Types of vessel groupings:
a, 6, c - annular vascular breeds with radial, tangential and scattered grouping, d-ras-sennovascular breed
vertical resin passages are visible as light dots located in the late wood of the annual layer; on longitudinal sections, resin passages are noticeable in the form of dark streaks directed along the axis of the trunk. The number and size of resin passages depends on the type of wood. In pine wood, resin passages are large and numerous, in larch wood, they are small and few.
Resin passages occupy a small volume of the trunk wood (0.2-0.7%) and therefore do not have a significant effect on the properties of the wood. They are important when tapping, when resin (sap) is obtained from growing trees.
§ 3. Microscopic structure of wood
Examination of wood under a microscope shows that it consists of the smallest particles - cells, mostly (up to 98%) dead. The plant cell has the thinnest transparent membrane, inside which there is a protoplast, consisting of the cytoplasm and the nucleus.
The cell membrane of young plant cells is a transparent, elastic and very thin (up to 0.001 mm) film. It consists of organic matter - fiber, or cellulose.
As it develops, depending on the functions that a particular cell is designed to perform, the size, composition and structure of its shell change significantly. The most common type of change in cell membranes is their lignification and corking.
Lignification of the cell wall occurs during the life of cells as a result of the formation of a special organic substance in them - lignin. Lignified cells either completely stop growing or increase in size to a much lesser extent than cells with cellulose membranes.
Cellulose in the cell wall is in the form of filaments called microfibrils. The spaces between microfibrils are filled mainly with lignin, hemicelluloses, and bound moisture.
During growth, the cell walls thicken, leaving non-thickened areas called pores. The pores are used to carry water with dissolved nutrients from one cell to another.
Types of wood cells. The cells that make up wood are varied in shape and size. There are two main types of cells: cells with a fiber length of 0.5-3 mm, a diameter of 0.01-0.05 mm, with pointed ends - prosenchymal cells and cells of smaller sizes, having the appearance of a multifaceted prism with approximately the same side dimensions (0, 01-0.1 mm), - parenchymal.
Parenchymal cells are used to store reserve nutrients. Organic nutrients in the form of starch, fats and other substances are accumulated and stored in these cells until spring, and in spring they are sent to the crown of the tree to form leaves. Rows of parenchymal cells are located in the tree along the radius and are part of the medullary rays. Their number in the total volume of wood is insignificant: for conifers 1-2%, for deciduous ones - 2-15%
The bulk of wood of all species consists of prosenchymal cells, which, depending on the vital functions they perform, are divided into conducting and supporting or mechanical. Conducting cells in a growing tree are used to conduct water with solutions of mineral substances from the soil into the crown; the supporting ones create the mechanical strength of the wood.
Wood fabrics. Cells of the same structure, performing the same functions, form wood tissues.
In accordance with the purpose and type of cells that make up the tissues, they are distinguished: storage, conductive, mechanical (supporting) and integumentary tissues.
Storage tissues (Fig. 7, a, b) consist of short storage cells and serve for the accumulation and storage of nutrients. Storage tissues are found in the trunk and roots.
Conductive tissues consist of elongated thin-walled cells (Fig. 7, c) (vessels, tubes) through which moisture absorbed by the roots passes to the leaves.
The length of the vessels is on average about 100 mm; in some species, for example, in oak, the vessels reach 2-3 m in length. The diameter of the vessels ranges from hundredths of a millimeter (in small-vessel rocks) to 0.5 mm (in large-vessel rocks).
Mechanical tissues (support) are in the trunk (Fig. 7, d). These fabrics give stability to the growing tree. The more of this fabric, the denser, harder and stronger the wood is. Mechanical fabrics are called libriform.
The integumentary tissues are located in the cortex and play a protective role.
The structure of coniferous wood. Coniferous wood is distinguished by its comparative simplicity and correct structure. Its main mass (90-95%) is made up of elongated cells located in radial rows with obliquely cut ends, called tracheids. In the walls of the tracheids there are pores through which they communicate with neighboring cells. Early and late tracheids are distinguished within the annual layer. Early tracheids (Fig. 7, e) are formed in spring and early summer, have thin membranes with pores, wide cavities, and serve to conduct water with dissolved minerals. In early tracheids, the size in the radial direction is larger than in the tangential one. The ends of the early tracheids are rounded.
Late tracheids are formed at the end of summer, have narrow cavities and thick cell membranes, therefore they perform a mechanical function, giving wood strength. The size in the radial direction is smaller than in the tangential direction.
The number of pores on the walls of early tracheids is about 3 times greater than on the walls of late tracheids. Tracheids are dead cells. In the trunk of a growing tree, only the newly formed annual layer contains living tracheids.
Resin passages are a feature of the structure of coniferous wood.
They are cells that make and store resin. Some species have only resin cells that are disconnected from each other (fir, yew, juniper), while other species have resin cells linked into a system and form resin passages (pine, spruce, larch, cedar). Distinguish between horizontal and vertical resin passages, which together constitute a single system of communicating channels.
Horizontal resin passages run along the pith rays and are clearly visible on the tangential section of the trunk.
The microscopic structure of coniferous wood is shown in f Fig. 8, a.
Woody parenchyma in conifers is not widespread and represents single parenchymal cells or cells elongated along the length of the trunk, or cells connected in long rows running along the axis of the trunk. Yew and pine have no woody parenchyma.
The structure of hardwood. Compared to conifers, deciduous species have a more complex structure (Fig. 8, b). Basic
the volume of deciduous wood is made up of vessels and vascular tracheids, libriform fibers, parenchymal cells.
Vessels are a system of cells that serve in a growing tree to carry water with dissolved minerals from the roots to the leaves. Water from the vessels passes to neighboring living cells through the pores in the side walls of the vessels.
Libriform fibers (see reef 8, b) are the most common cells of deciduous wood and make up their main mass (up to 76%). The rest of the wood volume is made up of cells of the woody parenchyma. These cells can be collected in vertical rows called cords of the tree parenchyma. Libriform fibers are long cells with pointed ends, thick membranes and narrow cavities. The walls of libriform fibers are always lignified, have narrow channels - slit-like pores. The length of the libriform fibers is in the range of 0.3-2 mm, and the thickness is 0.02-0.005 mm.
Libriform fibers are the strongest elements of hardwood and perform mechanical functions.
The size and quantitative ratio of the various cells that make up the wood, even in the same species, can vary depending on the age and growth conditions of the tree.
Parenchymal cells that perform spare functions in deciduous wood primarily form core rays.
The pith rays in deciduous species are more developed than in conifers. In width, the core rays can be narrow, single-row, consisting of one 4 rows of cells elongated along the radius, and wide, multi-row, consisting of several rows of cells in width. In height, the core rays consist of several tens of rows of cells (up to 100 or more in oak, beech). On a tangential section, single-row rays are presented in the form of a vertical chain of cells; multi-row beams are in the form of lentils.
Deciduous trees shed their leaves for the winter and need a large amount of reserve nutrients necessary for the formation of new leaves next spring, so deciduous wood contains more cells of the tree parenchyma.
The influence of the structure of wood on its physical and mechanical properties. The fine structure of the cell wall has a significant effect on the properties of wood. A decrease in the amount of bound moisture leads to a decrease in the distance between microfibrils, which increases the adhesion between them and the content of solid wood pulp per unit volume. All this leads to an improvement in the mechanical properties of wood. On the contrary, with an increase in the amount of bound moisture, microfibrils move apart, which reduces the mechanical properties of wood.
Microfibrils are located mainly along the long axis of the cell. This determines the high mechanical strength of the wood along the grain.
The sizes of individual anatomical elements also affect the physical and mechanical properties of wood. Since the late tracheids have a large wall thickness, an increase in the content of the late zone in the annual layers leads to an increase in density, hardness and mechanical strength. Likewise, in hardwoods, an increase in libriform fiber content, especially with thick walls, leads to an increase in mechanical properties.
Features of the microscopic structure of deciduous and coniferous wood determine the difference in their properties. The fibers of coniferous wood are rectilinear. Therefore, conifers have higher strength values at the same density. Hardwood has some
the tortuosity of the fibers, as a result of which it has a higher toughness and a higher strength when dripping along the fibers. The wood of deciduous ring-vascular species bends better, since vessels are located in the early wood, which enable the wood to be compacted without destruction.
2. Physical properties of wood
The physical properties of wood are those that are determined without violating the integrity of the test sample and changing its chemical composition, that is, they are identified by inspection, weighing, measuring, drying.
The physical properties of wood include: appearance and odor, density, moisture and associated changes - shrinkage, swelling, cracking and warping. The physical properties of wood also include its electrical, sound and thermal conductivity, indicators of macrostructure.

§ 4. Properties that determine the appearance of wood
The appearance of wood is determined by its color, gloss, texture and macrostructure.
Colour. The color of the wood is given by the tanning, resinous and dyes contained in it, which are in the cavities of the cells.
Wood species growing in different climatic conditions has a different color: from white (aspen, spruce, linden) to black (ebony). The wood of the species growing in hot and southern regions has a brighter color in comparison with the wood of the temperate zone. Within the climatic zone, each tree species has its own special color, which can serve as an additional sign for its recognition. So, hornbeam wood is light gray, oak and ash - brown, walnut - brown. Under the influence of light and air, wood of many species loses its brightness, acquiring a grayish color in the open air.
Alder wood, which has a light pink color when freshly cut, darkens soon after felling and acquires a yellowish-red color. Oak wood, which has been in water for a long time, becomes dark brown and even black (bog oak). The color of wood also changes as a result of its defeat by various types of fungi. The wood color is also influenced by the age of the tree. Young trees tend to have lighter wood than older trees. The wood of oak, pear and acacia, boxwood, chestnut has a stable color.
The color of the wood is important in the production of furniture, musical instruments, joinery and art products. The color rich in rich shades gives wood products a beautiful appearance. The color of some wood species is improved by subjecting it to various treatments - steaming (beech), pickling (oak, chestnut) or staining with various chemicals. The color of wood and its shades are usually characterized by definitions - red, white, pink, light pink and only if necessary, according to the atlas or color scale.
Gloss is the ability to directionally reflect the luminous flux. The luster of wood depends on its density, number, size and location of the core rays. Core beams have the ability to directionally reflect light beams and create radial sheen.
The wood of beech, maple, elm, sycamore, acacia, oak is distinguished by a special luster. The wood of aspen, linden, poplar, which has very narrow pith rays and relatively thin walls of cells of mechanical tissues, has a matte surface.
Gloss gives wood a beautiful look and can be enhanced by polishing, varnishing, waxing or overlaying with clear films made from artificial resins.
Texture - a pattern that is obtained on the cuts of wood when cutting its fibers, annual layers and pith rays. The texture depends on the features of the anatomical structure of individual wood species and the direction of the cut. It is determined by the width of the annual layers, the difference in the color of early and late wood, the presence of pith rays, large vessels, the irregular arrangement of the fibers (wavy or tangled). Conifers on a tangential section due to a sharp difference in the color of early and late woods give a beautiful texture. Hardwoods with pronounced annual layers and developed core rays (oak, beech, maple, elm, elm, sycamore) have a very beautiful texture on the radial and tangential sections (Fig. 9 in the inset). Wood with an irregular grain pattern (wavy and tangled curl) has a particularly beautiful pattern.
Softwoods and softwoods have a simpler and less varied pattern than hardwoods.
When using clearcoats, you can enhance and bring out the texture.
Often, special methods of wood processing are used - peeling plywood logs at an angle to the direction of the fibers, radial planing, pressing or replacing with an artificial texture - the surface is painted with an airbrush to match the texture of valuable species or pasted over with textured paper.
The texture determines the decorative value of wood, which is especially important in the manufacture of artistic furniture, various crafts, when decorating musical instruments, etc.
The smell of wood depends on the resins, essential oils, tannins and other substances contained in it. Conifers - pine, spruce - have a characteristic smell of turpentine. Oak has the smell of tannins, bakout and rosewood - vanilla. Juniper smells good, so its branches are used when steaming barrels. The smell of wood in the manufacture of containers is of great importance. When freshly cut, the wood has a stronger odor than when dry. The kernel smells stronger than sapwood. Individual species can be identified by the smell of wood.
Macrostructure. To characterize wood, it is sometimes sufficient to determine the following macrostructure indicators.
The width of the annual layers is determined by the number of layers per 1 cm of the segment measured in the radial direction at the end cut.
The width of the annual layers affects the properties of the wood. For coniferous wood, an improvement in properties is noted if there are at least 3 and no more than 25 layers in 1 cm. In deciduous ring-vascular species (oak, ash), the increase in the width of the annual layers occurs due to the late zone and therefore the strength, density and hardness increase. For hardwood scattered vascular wood (birch, beech) there is no such clear dependence of properties on the width of annual layers.
On samples from coniferous and annular vascular deciduous species, the content of late wood (in%) is determined. How
the higher the late wood content, the higher its density, and, consequently, the higher its mechanical properties.
The degree of uniformity is determined by the difference in the number of annual layers in two adjacent sections 1 cm long. This indicator is used to characterize the resonance capacity of spruce and fir wood.
When processing wood with cutting tools, the hollow anatomical elements (vessels) are cut and irregularities are formed on the surface of the wood. In species such as oak, ash, walnut, the amount of structural irregularities is significant. Since the wood of these species is used for finishing products, it is necessary to reduce the size of these irregularities before polishing. For this, a special operation is performed, which is called filling.

§ 5. Wood moisture and properties associated with its change
Humidity. Wood moisture is the ratio of the mass of moisture in a given volume of wood to the mass of absolutely dry wood, expressed in%. Determine the moisture content according to GOST 16588-79.
Absolutely dry wood in small samples can be obtained by drying it in special cabinets.
The moisture in the wood permeates the cell membranes and fills the cell cavities and intercellular spaces. The moisture that permeates the cell walls is called bound or hygroscopic. The moisture that fills the cell cavities and intercellular spaces is called free, or capillary.
When the wood dries, free moisture first evaporates from it, and then it is hygroscopic. When wood is moistened, moisture from the air soaks only the cell membranes until they are completely saturated. Further moistening of wood with filling of cell cavities and intercellular spaces occurs only with direct contact of wood with water (soaking, steaming, alloying).
The total amount of moisture in wood is made up of free and bound moisture. The limiting amount of free moisture depends on how large the volume of voids in the wood that can be filled with water.
The state of wood, in which the cell walls contain the maximum amount of bound moisture, and only air is in the cell cavities, is called the limit of hygroscopicity. The humidity corresponding to the limit of hygroscopicity at room temperature (20 ° C) is 30% and practically does not depend on the breed.
Distinguish the following levels of wood moisture: wet - for a long time in water, moisture above 100% freshly cut - moisture 50-10C%; air-dry - kept in the air for a long time, humidity 15-20% (depending on climatic conditions and season); room-dry - humidity 8-12% and absolutely dry - humidity 0%. The moisture content in the trunk of a growing tree varies with the height and radius of the trunk, as well as with the season. The moisture content of the pine sapwood is three times higher than the moisture content of the core. In hardwood, the change in moisture content in diameter is more uniform.
Along the height of the trunk, the moisture content of the sapwood in conifers increases up the trunk, while the moisture content of the core does not change. In deciduous trees, the moisture content of the sapwood does not change, while the moisture content of the core decreases up the trunk.
Young trees have higher moisture content and fluctuations during the year are greater than those of older trees. The greatest amount of moisture is contained in the winter (November-February), the minimum - in the summer months (July-August). The moisture content in the trunks changes during the day: in the morning and in the evening, the moisture content of the trees is higher than during the day.
To determine the moisture content of wood, use the drying method and the electric method.
END FRAGMENT OF THE BOOK

Introduction

Fundamentals of wood science

1. The structure of wood and wood
Tree structure
Macroscopic structure of wood
Microscopic structure of wood

2. Physical properties of wood
Properties that determine the appearance of wood
Wood moisture and properties associated with its change
Density of wood
Thermal conductivity, sound conductivity, electrical conductivity of wood

3. Mechanical properties of wood
General concepts of mechanical properties and wood testing
Durability of wood
Hardness, deformability and impact strength of wood
Technological properties of wood

4. Defects of wood
Knots
Cracks
Barrel shape defects
Defects in the structure of wood
Chemical paints
Fungal lesions
Damage to wood by insects
Foreign inclusions and defects
Deformation of wood

5. Characteristics of the main wood species and their industrial value
The main macroscopic features of wood for identifying species
Conifers
Hardwood
Foreign tree species

Adhesives and finishing materials

6. Adhesives
Types, composition and basic properties of adhesives
Animal adhesives
Casein adhesives
Synthetic adhesives

7. Paints and varnishes and other finishing materials
Dyes, fillers, solvents, thinners, plasticizers
Film-forming substances
Primers, fillers, putties and putties
Varnishes and varnishes
Paints and enamels

8. Film and sheet finishing materials
Film and sheet materials based on paper
Synthetic resin films
Decorative laminates

9. Supporting materials
Grinding materials
Polishing, degumming and bleaching compounds

Forestry merchandising

10. Classification and standardization of forest products

11. Round timber
Characteristics of round timber
Measurement, accounting and marking of round timber
Round timber storage

12. Lumber and blanks
Characteristics of lumber
Softwood and hardwood lumber
Blanks
Measurement, accounting and marking of lumber and blanks

13. Ways to extend the life of wood
Storage and air drying of wood
Protection of wood from rotting and destruction by insects
Fire protection of wood

14. Veneer, plywood and wood-based panels
Sliced and peeled veneer
Plain plywood
Plywood for special purposes
Plywood boards
Bent glued blanks
Joiner's boards
Fiber boards
Chipboards

15. Materials and products for construction
Window and balcony blocks
Door blocks
Materials and products for floors
Wooden milled and molded parts for construction
Roofing and other materials

16. Metal products and furniture fittings
Brief information about metals and alloys
Metal fasteners
Devices and products for windows and doors
Furniture fittings
Glass and mirrors

17. Insulating, bonding and lubricants
Insulation materials and mastics
Electrical insulating materials
Lubricants