Scale dimensions. Standard drawing scales

Machines and some of their parts, buildings and their parts are large, so it is not possible to draw them in full size. Their images have to be drawn in. The smallest details of wristwatches and other mechanisms have to be drawn, on the contrary, on an enlarged scale.

Whenever possible, details should be drawn in full size, i.e. on a 1: 1 scale.

It is not allowed to reduce or enlarge images by any number of times. GOST 2.302-68 established the following reduction scales: 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. The magnitude of the increase is recorded as a ratio to one; the standard sets the following magnification scales: 2: 1; 2.5: 1; 4: 1; 5: 1; 10: 1; 20: 1; 40: 1, 50: 1; 100: 1. In necessary cases, it is allowed to apply the magnification scales (100L): 1, where n is an integer. In cases where the full word "scale" is absent in the record, the letter M is put down in front of the scale designation, for example, they write: M 1: 2 (scale reduction), M 2: 1 (scale increase). In fig. 1 a rectangular washer is shown in three scales: full size (M 1: 1), scaled down and scaled up. The linear dimensions of the last image are four times larger than the average, and the area occupied by the image is sixteen times larger. Such a sharp change in the size of the image 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 are of two types: simple and transverse (Fig. 1). A simple linear scale corresponding to a numerical scale of 1: 100 is a line on which centimeter divisions are plotted to the right from zero division, and one same division, divided by millimeters, to the left. Each centimeter division on the linear scale corresponds to 100 cm (or 1 m). Each millimeter division corresponds, obviously, to one decimeter. Taking any size from the drawing with a meter, put one needle on the corresponding full division to the right of zero, on
example by 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 in the drawing;
gives more accurate readings, since the dimensions in the drawing are laid, as a rule, according to a given linear scale;
after photographing the drawing, the scale, decreasing proportionally, makes it possible to obtain dimensions without building a proportional scale.

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

Rice. 2. Scale graph

In design and production practice, they often use proportional (angular) scale... It is the simplest graph. Suppose you want to build 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 built and on its second side a segment is laid, reduced by 5 times (100: 5 = 20 mm); connect the obtained point C to point A. The value of 12.8 mm, corresponding to 66 mm, is taken with a caliper-measuring instrument directly from the graph, without calculating it and without using a ruler. The graph is built on graph paper or on paper, graphed into a cage.

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

INTERSTATE STANDARD

UNIFIED SYSTEM OF DESIGN DOCUMENTATION

SCALE

Moscow

INTERSTATE STANDARD

1. This standard specifies the scale of images and their designation in drawings of all industries and construction.

The standard does not apply to photographic drawings, illustrations in printed publications, etc.

(Modified edition, Amendment No. 1, No. 2).

2a. For the purposes of this standard, the following terms are used with appropriate definitions:

scale: The ratio of the linear dimension of a segment in the drawing to the corresponding linear dimension of the same segment in nature;

actual size scale: Scale with a ratio of 1: 1;

zoom scale: Scale with a ratio greater than 1: 1 (2: 1, etc.);

reduction scale: Scale with a ratio less than 1: 1 (1: 2, etc.).

(Introduced additionally, Amendment No. 2).

2. The scale of the images in the drawings should be selected from the following range:

The scale of the 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
Natural value
Magnification scale	2:1; 2,5:1; 4:1; 5:1; 10:1; 20:1; 40:1; 50:1; 100:1

3. When designing master plans for large objects, it is allowed to use a scale of 1: 2000; 1: 5000; 1: 10000; 1: 20,000; 1: 25000; 1: 50,000.

4. In necessary cases, it is allowed to apply the magnification scales (100 n): 1, where NS- an integer.

5. The scale indicated in the intended column of the title block of the drawing should be designated as 1: 1; 1: 2; 2: 1, etc.

The scale of the drawing is the ratio of its linear dimensions to the actual size of the depicted object. This makes it possible to judge the parameters of the object under consideration. It is not always possible to use natural dimensions when drawing up a drawing. There are several reasons for this:

Some parts are too large to be fully displayed on paper.
Other mechanisms or objects, on the other hand, are not large enough to be displayed. An example is a clock, the internal mechanism of which is physically impossible to display on paper in real size.

In such cases, images are drawn reduced or enlarged.

Standard scales

The scale of reduction includes:

1:2,5,
1:10,
1:15,
1:20,
1:25,
1:50.
1:75.

The first number indicates that the scale of the image is half the size of the subject. In the case when the part or mechanism is small, other designations are used: 2: 1, 2.5: 1, 5: 1, 10: 1. Also, the increase is made 20, 40, 50 and 100 times.

How to determine the scale

To correctly determine the scale of drawings in accordance with GOST, you need to know the parameters of a part or mechanism. If the item is large, then you can reduce it by dividing by the numbers presented. An example is resizing by half. If a part, reduced by half, will fit on a sheet of paper for a drawing, then the scale is 1: 2.

Any object that needs to be depicted can be measured using standard methods (using a ruler, for example), in order to then transfer them to paper. The same thing happens when you create something from a drawing. According to the indicated scale, the exact dimensions are determined.

Basically, drawings are used:

during construction,
when creating complex mechanisms,
during the development of parts.

Resizing allows you to work on the design of the item on a small surface of paper, which simplifies the process. If the scale of a certain section of the drawing is different (which happens during construction), then a designation with the desired number is placed near it.

When creating drawings, many students make mistakes due to lack of experience and knowledge. To avoid this, it is enough to order the services of our company. Experts will quickly complete the work, which will allow you to get a good grade and see an example of a high-quality drawing. In addition, we can order the execution of a term paper, thesis or an abstract, which will be completed strictly within the agreed time frame.

Why it is necessary to follow GOST

In the document regulating the application of inscriptions, tables, as well as technical requirements, the rules are highlighted, thanks to which the compilation of each drawing takes place in accordance with certain norms. This contributes to the creation of graphical information that is understandable for any engineer or builder who uses it in their professional activities.

Careful reading of the documents will allow you to correctly present the information and the scope of the drawings. GOST 2.302-68 * contains the following rules:

Additional text is created only if the presentation of graphical information is impractical.
Everything that is on the drawing should be written in short form.
Each label should be displayed parallel to the main one.
If abbreviations of words are not generally accepted, their presence is unacceptable.
Only short inscriptions are used around the images, which cannot interfere with the reading of the drawing.
If the leader line is directed to the surface of the part, then it should end with an arrow, and in the case when it intersects the contour and does not point to a certain place, its end is formed by a point.
If there is a large amount of information that needs to be indicated around the figure, it is framed.
If there are tables, then they are drawn up in an empty space next to the image.
When using letters to designate elements of the drawing, they are written in alphabetical order without gaps.

Compliance with all these rules will allow you to create a drawing that meets all the requirements and therefore will be convenient for use.

This is the ratio between the natural dimensions of an object or object to the linear dimensions shown in the drawing. The scales of the drawings can be expressed as a number, in which case they are called numerical scales and graphically linear scales.

The numerical scale is denoted by a fraction and shows the multiplicity of decreasing and also increasing the size of the objects shown in the drawing.Depending on the purpose of the drawings and also on the complexity of the shapes of the objects and structures depicted in the drawing, the following scales are used when drawing up drawing documents:

Decreases 1:2; 1:2.5; 1:4; 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;

Magnifications: 2:1; 2.5:1;4:1; 5:1; 10:1; 20:1; 40:1; 50:1; 100:1;

Life-size image 1: 1 In the process of designing master plans for large objects, the following scales are used: 1:2000; 1: 5000; 1:10000; 1:20000; 1: 25000; 1:50000 .

If a drawing is executed in one scale, then its value is indicated in the column of the title block of the drawing according to the 1: 1 type; 1: 2; 1: 100, and so on. If in the drawing any image is made in a scale that differs from the indicated scale in the title block of the drawing, then the scale of the M 1: 1 type is indicated; M1: 2 and so on under the appropriate image name.

When drawing up construction drawings and using a numerical scale, it is necessary to make calculations to determine the dimensions of the line segments that are applied to the drawing. For example, if the length of the depicted object is 4000 millimeters, and the numerical scale is 1: 50, in order to calculate the length of the segment in the drawing, it is necessary to divide 4000 millimeters by (reduction degree) 50, and put the resulting value of 80 millimeters on the drawing.

In order to shorten the calculations, use a scale bar or build a linear scale (see Figure 4 a) in a numerical scale of 1:50. Draw a straight line at the beginning in the drawing and lay the base of the scale on it several times. The base of the scale is the value that is obtained by dividing the unit of measurement adopted in this case (1 m = 1000 mm.) By the size of the reduction 1000: 50 = 20 millimeters.

On the left side, the first segment is divided into several equal parts, so that each division corresponds to an integer. If you divide this segment into ten equal parts, then each division will correspond to 0.1 meters, if you divide it into five parts, then 0.2 meters.

In order to use the constructed linear scale, for example, to take the size of 4650 millimeters, it is necessary to put one leg of the measuring compass at four meters, and put the other on the sixth and a half to the left of zero fractional division. In the case where the accuracy is insufficient, use the transverse scale.

Drawing Scales - Cross and Angular (Proportional)

The transverse scale allows you to determine the size with a certain margin of error. The error can be up to hundredths of the base unit of measurement. Figure 4b shows an example of determining the size equal to 4.65 m. Hundredths are taken on a vertical segment and tenths on a horizontal one.

In the case when an arbitrary scale is used and it is necessary to build a reduced or enlarged image of an object executed according to a given drawing format, an angular scale is used, or as it is also called proportional. The angular scale can be built in the form of a right-angled triangle.

The ratio of the legs of such a right-angled triangle is equal to the multiplicity of the image scale change (h: H). If necessary, the image is scaled using the angular scale, using only abstract values and at the same time the dimensions of the depicted object are not calculated. For example, when it is necessary to depict a given drawing on an enlarged scale.

For this we build a right-angled triangle (see Figure 4 c) ABC. In such a triangle, the vertical leg BC is equal to a segment of some straight line, which is taken on a given drawing. The horizontal leg AB is equal to the length of the segment on the scale of the enlarged drawing. In order to increase the desired line segment in a given drawing, for example, a segment h, it is necessary to lay it parallel to the BC leg of an angular scale (vertically), between the AC hypotenuse and AB leg.

In this case, the increased size of the desired segment will be equal to the size H taken (horizontally) on the AB side of the angular scale. The angular scale is also used when converting values from one numerical scale to another.

The scale is the ratio of the linear dimensions of the image in the drawing to its actual dimensions.

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

Table 5.3 - Scope of drawings

When designing master plans for large objects, it is allowed to use a scale of 1: 2000; 1: 5000; 1: 10000; 1: 20,000; 1: 25000; 1: 50,000.

5.3 Title block.

Each sheet is framed with a frame, the lines of which are spaced from the three sides of the format by 5 mm from the left side by 20 mm. On the frame line in the lower right corner of the format, the main inscription is placed in accordance with GOST 2.104-68. On A4 sheets, the title block 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 design documentation of the project are made in pencil. Schemes, graphs, tables are allowed to be performed with black ink (paste). All inscriptions on the drawing field, dimensional numbers, filling of the main inscription are made only in a drawing font in accordance with GOST 2.304-81.

Thematic titles on the sheets are not depicted, since the name of the sheet content is indicated in the title block. In cases where a sheet with one inscription contains several independent images (poster material), individual images or parts of the text are provided with titles.

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 apply Form 2a on subsequent sheets of drawings and diagrams.

The corner inscription for drawings and diagrams is located in accordance with Figure 5.1. It is to be filled in with the rotation of the sheet by 180 o or 90 o.

Figure 5.1 - Location of the title block in various drawings

In the columns of the main inscription, Figures 5.2, 5.3, 5.4, indicate:

- in column 1 - the name of the product or its component part: the name of the schedule or diagram, as well as the name of the document, if a code has been assigned to this document. The name should be short and written in the nominative singular. 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 sheet content in the order accepted in the technical literature, for example: "Economic indicators", "Technological map", etc .;

- in column 2 - the designation of the document (drawing, graphics, diagrams, specifications, etc.);

- in column 3 - the designation of the material (the column is filled only in the drawings of the parts). The designation includes the name, brand and standard or specification of the material. If the grade of the 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 material recording:

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

- KCH 30-6 GOST 1215-79 (ductile iron, 300 - tensile strength in MPa, 6 - elongation in%);

- VCh 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 of steel);

- Steel 20 GOST 1050-88 (carbon steel, high-quality structural steel, 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 not 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 (wrought bronze, O- tin 4%, C- zinc 4%, C- lead 17%);

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

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

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

- AK4M2Ts6 GOST 1583-93 (aluminum casting alloy, silicon 4%, copper 2%, zinc 6%);

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

When manufacturing parts from assortment:

- Square

(from a square bar with a side of a square of 40 mm in accordance with GOST 2591-88, steel grade 20 in accordance with GOST 1050-88);

- Hexagon

(from hot-rolled hexagonal steel 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);

(hot-rolled round steel of normal rolling accuracy in 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);

- Band

(strip steel 10 mm thick, 70 mm wide in accordance with GOST 103-76, steel grade St 3 in accordance with GOST 380-94, supplied in accordance with the technical requirements of GOST 535-88);

- Corner

(angle equal-flange steel with a size of 50x3 mm in accordance with GOST 8509-86, steel grade St 3 in accordance with GOST 380-94, normal rolling accuracy B, supplied in accordance with the technical requirements of GOST 535-88);

- I-beam

(I-beam hot-rolled 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 normal manufacturing accuracy, unmeasured length, with a nominal bore of 20 mm, wall thickness 2.8 mm, without thread and without coupling);

- Pipe Ts-R-20x2.8 - 6000 GOST 3262-75 (zinc-coated pipe of increased manufacturing accuracy, gauge length 6000 mm, nominal bore 20 mm, threaded);

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

(seamless steel pipe in accordance with GOST 8732-78 with an inner 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 - the letter assigned to this document in accordance with 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;

–ДП - documentation of the diploma project;

–DR - the documentation of the thesis;

–KP - course project documentation;

–КР - coursework documentation;

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

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

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

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

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

If the assembly drawing is made on two or more sheets and the images on separate sheets are made in 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;

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

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 for which the diploma project is being carried out is encrypted in column 2 - the designation of the document, in this column it is necessary to put down the name of the institute and the group code). For example: “PGSKhA 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:

- "Developed.";

- "Consult.";

- "Ruk. NS.";

- "Head. cafe. ";

- "N.control."

- Column 11 - the name 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 regulatory control are mandatory;

- Column 13 - date of signing the document;

Whenever possible, details should be drawn in full size, i.e. on a 1: 1 scale.

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Rice. 1. Comparison of different scales. Linear scales

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

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

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Rice. 2. Scale graph

Whenever possible, details should be drawn in full size, i.e. on a 1: 1 scale.

After defining the page parameters, the program by default displayed the program view containing all the model space occupied by the model - below.

Before we start working with viewports, it's a good idea to paste in a drawing format to see how much space we have. Of course, first insert something, you need to do something.

Note that the size of the drawing is too large for a particular page layout - you must measure it to make sure the size of the layout is incorrect.

Please note that the form was inserted as a block, so you just need to point it anywhere and everything will be selected.

As a result of this simple operation, a drawing format was created. Contains tools for sizing objects. It is good to re-size the operation as shown below.

As you can see in the picture below, the defined paper area and printable area do not overlap with the drawing size.

Now that the page parameters are as expected, you can start "layout" of the drawing, that is, the layout of projections, details, adding comments to the drawing. During design, it is important to know that design elements will undergo changes over time, such as changes in shape or material resulting from, for example, technological changes, modernization caused by better adaptation to the market, etc. which should be inserted in the same way as the drawing format - the picture below.

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Rice. 1. Comparison of different scales. Linear scales

You can now start working with viewports.

Notice that the viewport border has changed from thin to thick, which means you can edit model space from paper space. The actions that can be performed here are no different from those in model space, and most importantly, the changes you make here are reflected in model space.

As you can see, this is not possible because both the drawing table and the revision table take up too much space. In this case, resize the viewport to a smaller one, or insert a larger drawing format.

Now that the main view and its cross-section are obtained by intersecting the drawn object represented by the cutting line.

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

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

The result of the above operation is a viewport with an undefined pitch, which shows everything that is drawn in model space - in the figure below.

Please note that at the moment there are two viewports in the drawing, only one of which is active, i.e. one where model space can be edited. It can be recognized by a bold frame, and the mouse cursor that is located above it is a crosshair with a choice of "viewfinder" - a cursor located above inactive darts - an arrow - the figure below.

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Rice. 2. Scale graph

You can change the inactive rollover to active in a very simple way - just hover over the cursor and left-click. Deliberately inserted, as shown in previous chapters, has a default rectangle shape. However, nothing prevents you from defining your own shape.

However, when the ellipse is specified in the Properties window, there is no Scale Factor option - in the image below.

When creating the layer, the viewfinder was set to a thickness of 0.5, which was not the best, since it lost one of the characteristics of the active viewport - bold. The thickness of the frame is not important, because the layer can be hidden or blocked before printing - this is only the comfort of work.

Of course, this element can be manually copied by removing unnecessary elements from it, but it can also save you valuable time.

The effect above is a viewport in which the only visible layer is the outline layer - pictured below.

Speaking about the text in the drawings, it is usually considered that the comments to the drawings, collected by the designer in the form of compact descriptions of points, supplement the executive drawing of information that cannot be transmitted in the form of symbols or symbols. These comments are usually placed above the table of drawings, although this is not a hard rule and in the absence of space - in any free space of the drawing form, of course, so as not to reduce the readability of the drawing.

Decreases 1:2; 1:2.5; 1:4; 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;

Completing the drawing table is one of the final steps to create an executive drawing. The layout of the protrusions and their resins has already been determined, the material from which the part is made is known, and this figure will be checked and verified - in a word, all the data required to complete it is known. Of course, this is not a rule, the table can be filled at the beginning, but then some data will almost certainly change, and you will have to remember to view and update the entire table, and often it is not remembered.

Magnifications: 2:1; 2.5:1;4:1; 5:1; 10:1; 20:1; 40:1; 50:1; 100:1;

Life-size image 1: 1 In the process of designing master plans for large objects, the following scales are used: 1:2000; 1: 5000; 1:10000; 1:20000; 1: 25000; 1:50000 .

Drawing Scales - Cross and Angular (Proportional)

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

GOST 2.302-68 Unified system for design documentation. The scale.

GOST 21.501-2011 System of design documentation for construction. Rules for the implementation of working documentation for 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, assemblies, circuits, as a rule, do not correspond to their real dimensions. The ratio of the size of the graphic image to the size of the displayed object is in a certain ratio, which is usually called the scale. To be precise:

The scale is the ratio of the linear dimensions of the image of the object in the drawing to its actual dimensions.

In accordance with GOST R21.1101-2013 on construction drawings, as a rule, the scale is not
affix.

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

In some cases, you have to choose other scales. Consider a general list of existing scales.

GOST 2.302 sets the scale of images for drawings.

The scales can be of the following types:

Natural	Zoom 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 scale of the image should be taken as minimal, depending on the complexity of the drawing, but ensuring the clarity of copies made from them.

Scale- the ratio of the linear dimensions of the object shown in the drawing to its dimensions in nature. The scale can be expressed as a number (numeric scale) or displayed graphically (linear scale).

Numerical scale denote by a fraction, which shows the multiplicity of increasing or decreasing the size of the image in the drawing. When executing drawings, depending on their purpose, the complexity of the shapes of objects and structures, their sizes, the following numerical scales are used ( GOST 2.302-68) *:

decrease: 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;
increase: 2: 1; 2.5: 1; 4: 1; 5: 1; 10: I; 20: 1; 40: 1; 50: 1; 100: 1;
actual size 1:1.

When designing master plans for large objects, a scale of 1: 2000 is used; 1: 5000; 1: 10,000; 1: 20,000; 1: 25,000; 1: 50,000.

In the event that the drawing is made on the same scale, its value is indicated in the main inscription of the drawings in the 1: 1 type intended for this column; 1: 2; 1: 100, etc. If any image in the drawing is made on a scale that differs from that indicated in the main inscription, then under the corresponding name of the image, a scale of the type M 1: 1 is indicated; M 1: 2, etc.

Applying a numerical scale when making drawings, you have to do calculations in order to determine the dimensions of the line segments drawn on the drawing. For example, to determine the length of a segment in a drawing with a length of the depicted object of 4000 mm and a numerical scale of 1:50, divide 4000 mm by 50 (the degree of reduction) and put the resulting value (80 mm) on the drawing.

To reduce calculations, use a scale ruler or build the corresponding numerical linear scale, as shown in the figure for a numeric scale of 1: 50.

A straight line is drawn and the base of the scale is laid on it several times - the value that is obtained as a result of dividing the adopted unit of measurement (1 m = 1000 mm) by the size of the reduction 1000: 50 = 20 mm. The first segment on the left side is divided into several equal parts so that each division corresponds to an integer. If this segment is divided into 10 parts, then each division will correspond to 0.1 m; if into 5 parts, then 0.2 m. Above the dividing points of the line into segments equal to the base of the scale, numerical values are inscribed that correspond to natural sizes, while the first division on the right is always set to zero. The value of small divisions from zero to the left is also labeled, as shown in the figure.

In order to take, using the constructed linear scale, for example, the size of 4.65 m (4650 mm), you need to put one leg of the measuring compass at 4 m, and the other at the sixth and a half fractional division to the left of zero. If the accuracy is insufficient, a transverse scale is used.

Transverse scale makes it possible to express or determine the size with an error of up to hundredths of the basic unit of measurement. So, the figure below shows the definition of a size equal to 4.65 m.

Tenths are taken on the horizontal scale segment, and hundredths - on the vertical.

In cases where it is required to build an enlarged or reduced image, performed according to a given drawing, the scale of which can be arbitrary, apply an angular (proportional) scale.

The angular scale is built in the form of a right-angled triangle, the ratio of the legs of which is equal to the multiplicity of the zoom (h: H). Using the angular scale, you can change the scale of the image, using abstract values and without calculating the size of the displayed object.
For example, you want to display a given drawing on an enlarged scale. To do this, we build a right-angled triangle ABC, in which the vertical leg BC is equal to a segment of any straight line taken in the given drawing, and the horizontal leg AB is equal to the length of the corresponding segment on the scale of the enlarged drawing. Thus, in order to increase any segment of a straight line of a given drawing, for example h, it is necessary to lay it parallel to the leg BC of an angular scale (vertically) between leg AB and hypotenuse AC, Then the increased size of the segment will be equal to the size H taken (horizontally) on the AB side of the angular scale.

Another method can be applied. As in the first case, we postpone vertically any segment of the given drawing h. Then, in the same place, we postpone the length of the segment h1 with the corresponding increase and draw an oblique line AD through the obtained point. We obtain the required segments in a similar way. It is convenient to use the meter when drawing an angular scale on graph paper.
The angular scale can also be used to convert values from one numeric scale to another.

In the enlarged drawing, as well as in the given one, it is necessary to indicate in numbers the actual dimensions that the depicted object has in nature, and not in the drawing.