What does the linear scale in the drawing mean? Using scales when depicting drawings

Before you start looking at standard drawing scales, you should understand what exactly this concept is. So, such a value is, in general, the ratio of two linear dimensions. However, this interpretation is more widely known this definition, as the ratio of the size of the drawing to the dimensions of the real object. Therefore, we can quite rightly assume that the above term has found wide application in cartography, geodesy and, of course, design.

Why is this necessary?

As mentioned earlier, real objects can have both quite significant sizes and very small ones. However, a person cannot sketch everything in life size, since to display on a sheet of paper a canvas of colossal dimensions would be required, and, in turn, to recreate small elements (as, for example, in a clock mechanism) would require high degree detailing. As a result, a person has adapted to depict the necessary objects, which are reduced (or enlarged) by a certain number of times for ease of perception and the so-called “readability” of the drawing. Currently, certain standards are in force, for example, GOST "Scales of drawings", which describe all the requirements for the type and content of the corresponding images.

Large objects

As mentioned earlier, to display buildings and other large objects, it is necessary to use the scale of the so-called reduction drawings. They are standardized, which means a random sample will not work. The most common values are: 1: 2; 2.5; 4; 5; 10; 15; 20; 25; 40; 50; 75; 100; 200; 400; 500; 800; 1000. Let's consider what a record of this type means. So, the real (in other words, natural) dimension of any object is expressed in the form of an inscription 1: 1. Consequently, when reduced, the scales of the drawings first describe the original size (1), and then a number that shows how many times the drawing is reduced in relation to actual dimensions. In construction, in addition to the above standard records, 1:2000 indicators may also be used; 5000; 10,000; 20,000; 25,000; 50,000.

Small details

If it is necessary to depict small objects in the drawing, then the scale of enlarged drawings is traditionally used. IN in this case There is not such a wide variety of values, but the standard specifies the most commonly used values. So, the typical series looks like this: 2; 2.5; 4; 5; 10; 20; 40; 50; 100: 1. The decoding of such inscriptions reads like this: first, a number indicating how many times the image in the drawing is enlarged compared to the original object. The second digit after the colon displays the real (also known as natural or real) size of the object in question (it is taken equal to 1).

Conclusion

This article examined the scale of the drawings and their standard rows. It should also be noted that on the plans, projects and images themselves, the scale value is indicated in a specially designated box in a frame, otherwise called a stamp.

Machines and some of their parts, buildings and their parts have large sizes, therefore it is not possible to draw them in full size. Their images have to be drawn in . Smallest details wristwatch and other mechanisms have to be drawn, on the contrary, on an enlarged scale.

In all cases where possible, details should be drawn in actual size, i.e. on a scale of 1:1.

Reducing or enlarging images any number of times is not permitted. GOST 2.302-68 installed following scales reduction: 1:2; 1:2.5; 1:4; 1:5; 1:10; 1:15; 1:20; 1:25; 1:40; 1:50; 1:75; 1:100; 1:200; 1:400; 1:500; 1:800; 1:1000. When drawing up master plans for large objects, it is allowed to use a scale of 1:2000; 1:5000; 1:10,000; 1:20,000; 1:25,000; 1:50,000. Magnification scales are written as a ratio to unity; The standard establishes the following magnification scales: 2:1; 2.5:1; 4:1; 5:1; 10:1; 20:1; 40:1, 50:1; 100:1. If necessary, it is allowed to use magnification scales (100l): 1, where n is an integer. In cases where full word“scale” is not included in the entry; the letter M is placed before the scale designation, for example they write: M 1:2 (reduction scale), M 2:1 (increase scale). In Fig. 1 washer rectangular shape depicted in three scales: life-size (M 1:1), reduced scale and enlarged scale. The linear dimensions of the last image are four times larger than the middle one, and the area occupied by the image is sixteen times larger. Such a sharp change in image size should be taken into account when choosing the scale of the drawing.

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Rice. 1. Comparison of different scales. Linear scales

In addition to numerical scales, linear scales are used in drawing. Linear scales There are two types: simple and transverse (Fig. 1). A simple linear scale, corresponding to a numerical scale of 1: 100, is a line on which, from the zero division, centimeter divisions are laid out to the right, and one of the same divisions, divided into millimeters, to the left. Each centimeter division of the linear scale corresponds to 100 cm (or 1 m). Each millimeter division corresponds, obviously, to one decimeter. Having taken any size from the drawing with a meter, place one needle on the corresponding full division to the right of zero, on -
example for division 3. Then the second needle will show how many decimeters over 3 m the measured size has. In this case it is equal to 3.4 m.

The advantages of a simple linear scale over a regular ruler are as follows:

it is always on the drawing;
gives more accurate readings, since the dimensions in the drawing are plotted, as a rule, according to a given linear scale;
After photographing the drawing, the scale, decreasing proportionally, makes it possible to obtain dimensions without constructing a proportional scale.

More perfect is linear transverse scale. In the drawing it is given for the same scale of 1:100. Oblique lines, transversals, allow you to get not only decimeters, but also centimeters. As an example, the scale shows a size of 3.48 m. Linear scales are used mainly in construction and topographical drawings.

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Rice. 2. Scale chart

In design and production practice they often use proportional (angular) scale. It is a simple graph. Suppose you need to construct such a graph for a scale of 1:5. On a horizontal line from point A (Fig. 2) lay a segment equal to 100 mm; at point B, a right angle is constructed and a segment reduced by 5 times (100: 5 = 20 mm) is laid along its second side; connect the resulting point C to point A. The value of 12.8 mm, corresponding to 66 mm, is taken with a measuring compass directly from the graph, without calculating it or using a ruler. The graph is drawn on graph paper or on checkered paper.

For a scale of 1: 2.5, 40 mm are set aside on the continuation of the BC leg, for a scale of 1: 2-50 mm. The series of proportional scales shown in the figure is called a scale graph. Using it allows you to save a significant amount of time. Having constructed a scale graph, use it throughout the entire work on the drawing course.

Scale is the ratio of the linear dimensions of an image in a drawing to its actual dimensions.

The scale of images and their designation in drawings is established by GOST 2.302-68 (Table 5.3). The scale indicated in the designated column of the title block of the drawing should be indicated as 1:1; 1:2; 1:4; 2:1; 5:1; etc.

Table 5.3 – Drawing scales

When designing master plans for large objects, it is allowed to use a scale of 1:2000; 1:5000; 1:10000; 1:20000; 1:25000; 1:50000.

5.3 Main inscription.

Each sheet is decorated with a frame, the lines of which are spaced from three sides of the format by 5 mm from the left side by 20 mm. The main inscription in accordance with GOST 2.104-68 is placed on the frame line in the lower right corner of the format. On A4 sheets, the main inscription is placed only along the short side. The type and thickness of lines in drawings, diagrams and graphs must comply with GOST 2.303-68. Drawings design documentation The project is carried out in pencil. Schemes, graphs, and tables may be made in black ink (paste). All inscriptions on the drawing field, dimensional numbers, and filling in the main inscription are made only in drawing font in accordance with GOST 2.304-81.

Thematic headings are not shown on the sheets, since the name of the contents of the sheet is indicated in the main inscription. In cases where a sheet with one inscription contains several independent images (poster material), individual images or parts of text are provided with headings.

The main inscription on the first sheets of drawings and diagrams must correspond to Form 1, in text design documents - Form 2 and Form 2a on subsequent sheets. It is allowed to use Form 2a on subsequent sheets of drawings and diagrams.

The corner inscription for drawings and diagrams is located in accordance with Figure 5.1. Filled by rotating the sheet 180 o or 90 o.

Figure 5.1–Location of title block on various drawings

In the columns of the title block, Figures 5.2, 5.3, 5.4, indicate:

– in column 1 – name of the product or its component: name of the graph or diagram, as well as the name of the document, if this document is assigned a code. The name must be short and written in the nominative singular case. If it consists of several words, then a noun is placed in the first place, for example: “Threshing drum”, “Safety clutch”, etc. It is allowed to write in this column the name of the contents of the sheet in the order accepted in the technical literature, for example: “Economic indicators”, “Technological map”, etc.;

– in column 2 – designation of the document (drawing, graphics, diagram, specification, etc.);

– in column 3 – designation of the material (the column is filled in only on drawings of parts). The designation includes the name, brand and standard or specification of the material. If the brand of a material contains its abbreviated name “St”, “SCh”, then the name of this material is not indicated.

Figure 5.2 – Form No. 1

Figure 5.3 – Form No. 2

Figure 5.4 – Form No. 2a

Examples of recording material:

– SCh 25 GOST 1412-85 (gray cast iron, 250 - tensile strength in MPa);

– KCh 30-6 GOST 1215-79 (malleable cast iron, 300 - tensile strength in MPa, 6 - relative elongation in%);

– HF 60 GOST 7293-85 (high-strength cast iron, 600 - tensile strength in MPa);

– St 3 GOST 380-94 (carbon steel of ordinary quality, 3- serial number steel);

– Steel 20 GOST 1050-88 (carbon steel, high-quality structural, 20 - carbon content in hundredths of a percent);

– Steel 30 KhNZA GOST 4543-71 (alloy structural steel, 30 - carbon content in hundredths of a percent, chromium no more than 1.5%, nickel 3%, A - high quality);

– Steel U8G GOST 1425-90 (tool carbon steel, 8 - carbon content in tenths of a percent; G - increased manganese content);

– Br04Ts4S17 GOST 613-79 (deformable bronze, O-tin 4%, C-zinc 4%, C-lead 17%);

– BrA9Mts2 GOST 18175-78 (tin-free bronze , processed by pressure, A- aluminum 9%, manganese 2%);

– LTs38Mts2S2 GOST 17711-93 (cast brass, zinc 38%, manganese 2%, lead 2%);

– AL2 GOST 1583-89 (casting aluminum alloy, 2-order alloy number);

– AK4M2TS6 GOST 1583-93 (cast aluminum alloy, silicon 4%, copper 2%, zinc 6%);

– AMts GOST 4784-74 (deformable aluminum alloy, manganese 1.0...1.6%,).

When manufacturing parts from the assortment:

- Square
(from a square profile bar with a square side size of 40 mm according to GOST 2591-88, steel grade 20 according to GOST 1050-88);

– Hexagon
(made of hot-rolled steel with a hexagonal profile in accordance with GOST 2579-88 of normal rolling accuracy, with the size of an inscribed circle - turnkey size - 22 mm, steel grade 25 in accordance with GOST 1050-88);

- Circle
(hot-rolled round steel of normal rolling accuracy with a diameter of 20 mm in accordance with GOST 2590-88, steel grade St 3 in accordance with GOST 380-94, supplied in accordance with the technical requirements of GOST 535-88);

– Strip
(strip steel 10 mm thick, 70 mm wide according to GOST 103-76, steel grade St 3 according to GOST 380-94, supplied according to the technical requirements of GOST 535-88);

– Corner
(angular equal-flange steel 50x3 mm in size according to GOST 8509-86, steel grade St 3 according to GOST 380-94, standard rolling accuracy B, supplied according to the technical requirements of GOST 535-88);

– I-beam
(hot-rolled I-beam number 30 in accordance with GOST 8239-89 of increased accuracy (B), steel grade St 5 in accordance with GOST 380-94, supplied in accordance with the technical requirements of GOST 535-88);

– Pipe 20x2.8 GOST 3262-75 (ordinary non-galvanized pipe of standard manufacturing precision, of unmeasured length, with a nominal bore of 20 mm, a wall thickness of 2.8 mm, without threads and without a coupling);

– Pipe Ts-R-20x2.8 – 6000 GOST 3262-75 (zinc-coated pipe with increased manufacturing precision, measured length 6000 mm, nominal bore 20 mm, with thread);

- Pipe
(seamless steel pipe of standard manufacturing precision according to GOST 8732-78, with an outer diameter of 70 mm, a wall thickness of 3.5 mm, a length multiple of 1250 mm, steel grade 10, manufactured according to group B of GOST 8731-87);

- Pipe
(seamless steel pipe in accordance with GOST 8732-78 with an internal diameter of 70 mm, wall thickness 16 mm, unmeasured length, steel grade 20, category 1, manufactured according to group A, GOST 8731-87);

– Column 4 – letter assigned to this document according to GOST 2.103-68 depending on the nature of the work in the form of a project. The column is filled in from the left cell:

–U – educational document;

–DP – documentation of the diploma project;

–DR – documentation of the thesis;

–KP – course project documentation;

–KR – documentation of course work;

– Column 5 – product weight (in kg) according to GOST 2.110-95; on drawings of parts and assembly drawings indicate the theoretical or actual mass of the product (in kg) without indicating units of measurement.

It is allowed to indicate the mass in other units of measurement indicating them, for example, 0.25 g, 15 t.

In drawings made on several sheets, the mass is indicated only on the first.

On dimensional and installation drawings, as well as on drawings of parts of prototypes and individual production, it is allowed not to indicate the mass;

– Column 6 – scale (indicated in accordance with GOST 2.302-68).

If the assembly drawing is made on two or more sheets and the images on individual sheets are made on a scale different from that indicated in the title block of the first sheet, column 6 of the title block on these sheets is not filled out;

– Column 7 – serial number of the sheet (on documents consisting of one sheet, the column is not filled in).

Column 8 – the total number of sheets of the document (the column is filled out only on the first sheet).

Column 9 - the name or distinctive index of the enterprise issuing the document (since the department in which the diploma project is being carried out is encrypted in column 2 - designation of the document, in this column it is necessary to enter the name of the institute and the group code). For example: “PGSHA gr. To-51";

– Column 10 – the nature of the work performed by the person signing the document. In the diploma project, the column is filled in starting from the top line with the following abbreviations:

– “Developer”;

– “Consult.”;

- “Hand. etc.";

- “Head. cafe";

- “N.cont.”

– Column 11 – surname of the persons who signed the document;

– Column 12 – signatures of persons whose names are indicated in column 2. Signatures of the persons who developed this document and are responsible for standard control are mandatory;

– Box 13 – date of signing of the document;

Scale is the ratio of the linear dimensions of an image in a drawing to its actual dimensions.

Table 5.3 – Drawing scales

When designing master plans for large objects, it is allowed to use a scale of 1:2000; 1:5000; 1:10000; 1:20000; 1:25000; 1:50000.

5.3 Main inscription.

Each sheet is decorated with a frame, the lines of which are spaced from three sides of the format by 5 mm from the left side by 20 mm. The main inscription in accordance with GOST 2.104-68 is placed on the frame line in the lower right corner of the format. On A4 sheets, the main inscription is placed only along the short side. The type and thickness of lines in drawings, diagrams and graphs must comply with GOST 2.303-68. Drawings of the project design documentation are made in pencil. Schemes, graphs, and tables may be made in black ink (paste). All inscriptions on the drawing field, dimensional numbers, and filling in the main inscription are made only in drawing font in accordance with GOST 2.304-81.

The corner inscription for drawings and diagrams is located in accordance with Figure 5.1. Filled by rotating the sheet 180 o or 90 o.

Figure 5.1–Location of title block on various drawings

In the columns of the title block, Figures 5.2, 5.3, 5.4, indicate:

– in column 2 – designation of the document (drawing, graphics, diagram, specification, etc.);

Figure 5.2 – Form No. 1

Figure 5.3 – Form No. 2

Figure 5.4 – Form No. 2a

Examples of recording material:

– SCh 25 GOST 1412-85 (gray cast iron, 250 - tensile strength in MPa);

– KCh 30-6 GOST 1215-79 (malleable cast iron, 300 - tensile strength in MPa, 6 - relative elongation in%);

– HF 60 GOST 7293-85 (high-strength cast iron, 600 - tensile strength in MPa);

– St 3 GOST 380-94 (carbon steel of ordinary quality, 3rd steel number);

– Steel 20 GOST 1050-88 (carbon steel, high-quality structural, 20 - carbon content in hundredths of a percent);

– Steel 30 KhNZA GOST 4543-71 (alloy structural steel, 30 - carbon content in hundredths of a percent, chromium no more than 1.5%, nickel 3%, A - high quality);

– Steel U8G GOST 1425-90 (tool carbon steel, 8 - carbon content in tenths of a percent; G - increased manganese content);

– Br04Ts4S17 GOST 613-79 (deformable bronze, O-tin 4%, C-zinc 4%, C-lead 17%);

– BrA9Mts2 GOST 18175-78 (tin-free bronze , processed by pressure, A- aluminum 9%, manganese 2%);

– LTs38Mts2S2 GOST 17711-93 (cast brass, zinc 38%, manganese 2%, lead 2%);

– AL2 GOST 1583-89 (casting aluminum alloy, 2-order alloy number);

– AK4M2TS6 GOST 1583-93 (cast aluminum alloy, silicon 4%, copper 2%, zinc 6%);

– AMts GOST 4784-74 (deformable aluminum alloy, manganese 1.0...1.6%,).

When manufacturing parts from the assortment:

- Square
(from a square profile bar with a square side size of 40 mm according to GOST 2591-88, steel grade 20 according to GOST 1050-88);

– Strip
(strip steel 10 mm thick, 70 mm wide according to GOST 103-76, steel grade St 3 according to GOST 380-94, supplied according to the technical requirements of GOST 535-88);

– Pipe Ts-R-20x2.8 – 6000 GOST 3262-75 (zinc-coated pipe with increased manufacturing precision, measured length 6000 mm, nominal bore 20 mm, with thread);

– Column 4 – letter assigned to this document according to GOST 2.103-68 depending on the nature of the work in the form of a project. The column is filled in from the left cell:

–U – educational document;

–DP – documentation of the diploma project;

–DR – documentation of the thesis;

–KP – course project documentation;

–KR – documentation of course work;

It is allowed to indicate the mass in other units of measurement indicating them, for example, 0.25 g, 15 t.

In drawings made on several sheets, the mass is indicated only on the first.

On dimensional and installation drawings, as well as on drawings of parts of prototypes and individual production, it is allowed not to indicate the mass;

– Column 6 – scale (indicated in accordance with GOST 2.302-68).

– Column 7 – serial number of the sheet (on documents consisting of one sheet, the column is not filled in).

Column 8 – the total number of sheets of the document (the column is filled out only on the first sheet).

– Column 10 – the nature of the work performed by the person signing the document. In the diploma project, the column is filled in starting from the top line with the following abbreviations:

– “Developer”;

– “Consult.”;

- “Hand. etc.";

- “Head. cafe";

- “N.cont.”

– Column 11 – surname of the persons who signed the document;

– Column 12 – signatures of persons whose names are indicated in column 2. Signatures of the persons who developed this document and are responsible for standard control are mandatory;

– Box 13 – date of signing of the document;

When choosing a scale for drawings, we use the following GOST standards:

GOST 2.302-68 Unified system of design documentation. Scale.

GOST 21.501-2011 System of design documentation for construction. Rules for the execution of working documentation of architectural and structural solutions.

GOST R 21.1101-2013 System of design documentation for construction. Basic requirements for design and working documentation

When developing drawings, the dimensions of graphic images of structures, components, and diagrams, as a rule, do not correspond actual sizes. The ratio of the size of a graphic image to the size of the depicted object is in a certain ratio, which is usually called scale. To be precise:

Scale is the ratio of the linear dimensions of the image of an object in the drawing to its actual dimensions.

In accordance with GOST R21.1101-2013 for construction drawings, as a rule, the scale is not
put down.

In cases where the images on the sheet are made in different scales, the corresponding scale is indicated above each of them.
Architectural and construction drawings of residential and public buildings are carried out on the following scales:
floor plans, sections, facades – 1:50; 1:100; 1:200
fragments of plans, sections, facades – 1:50; 1:100
knots – 1:5; 1:10; 1:20
master plan – 1:500; 1:1000

In some cases it is necessary to choose other scales. Let's look at the general list of existing scales.

GOST 2.302 establishes the scale of images for drawings.

Scales can be of the following types:

Natural	Magnification scale	Reduction scale
1:1	1: 2	2:1
	1:2,5	2,5:1
	1:4	4:1
	1:5	5:1
	1:10	10:1
	1:15	20:1
	1:20	40:1
	1:25	50:1
	1:40	100:1
	1:50
	1:75
	1:100
	1:200
	1:400
	1:500
	1:800
	1:1000

When developing drawings, the image scale should be taken as minimal as possible, depending on the complexity of the drawing, but ensuring the clarity of copies made from them.