Part numbers are indicated on the assembly drawing. Creation of assembly drawing and specification

Methods for creating assembly drawings

Before you start creating an assembly drawing, it is advisable to think about its structure. At the same time, you need to try to determine the requirements for its parametric capabilities: what exactly will need to be changed later, what parts will make up the drawing, what hierarchy of fragments is expected. From the results of this preliminary analysis It will depend on which method of creating an assembly model and fragments to give preference to. The difference between the methods for designing assembly drawings is in the way the fragment file is created:

● Bottom-up design. When using this method, first in separate T-FLEX CAD documents in the usual way Drawings of parts included in the assembly are created. Creating an assembly drawing in this case consists of sequentially applying the necessary fragments to it. In this case, it is necessary to solve the problem of linking the image of the part to the assembly drawing.

● Top-down design.The meaning of this method is that the basis for the part drawing is taken from the assembly drawing, i.e. creation of fragments occurs in the context of an assembly. In this case, design begins with the creation of an assembly drawing. Already created parts of an assembly drawing, including graphic lines and fragment nodes, can be used to create new fragments. This approach simplifies the creation of associative links between assembly fragments and the process of linking them. The created fragments are saved in separate documents for further refinement and/or use in other assembly drawings.

The described methods can be combined. For example, a fragment created and applied to an assembly using the “Bottom-Up” method can subsequently be edited in the context of the assembly. And a fragment created in the context of an assembly can subsequently be used to create other assemblies using the Bottom-Up method.

Methods for linking a fragment image to an assembly drawing

To place an image of a fragment in the right place on an assembly drawing in the T-FLEX CAD system, there are several different methods using different tools depending on the task being solved:

4. Without reference (transfer “as is”, in absolute coordinates). If there are no vectors and anchor points when working with the “Bottom-up” method, as well as when all anchors are disabled when working with the “Top-down” method, the system transfers the image of the fragment to the assembly drawing page without changes. Each line or node of a fragment receives the same coordinates on the assembly drawing that they had in the fragment document.

5. Using Special Variable Functions. In some cases, when plotting fragments in absolute coordinates, you can use the T-FLEX CAD variable functions. For example, this is used for applying formats. In a parametric format drawing, special functions are used that read the coordinates of the page boundaries of the assembly document. The coordinates are then passed through variables to the corresponding construction lines. Thus, the format automatically takes the required size, in accordance with the specified page dimensions of the assembly drawing.

Using Fragment Variables

When drawing a fragment, you can set the values ​​of the variables that control its drawing. To do this, it is necessary that when creating a fragment drawing, the necessary variables are marked as external. For example, if you want to set the radius of a fragment's circle when including its image in other drawings, you need to assign an external variable when creating a circle construction line (for example, " R ") by the radius of the circle. After that, each time this fragment is included in other drawings, the system will request the value of the variable "R" and, in accordance with the entered value, change the image of the fragment.

External variables of a fragment play an important role in connecting the parameters of the fragment and the assembly drawing. For example, the drawing contains an image of a shaft, the diameter of which has been assigned the variable " Diameter".

Let's say you need to place a bearing on a shaft. A variable was created in the bearing drawing " d ", which is responsible for the value of the internal diameter of the bearing. Variable " d " is marked as external. All other bearing parameters are related in such a way that they depend on the value " d".

Now, when the bearing is applied to the shaft drawing, it will be possible to relate the two variables to each other. After these actions, the change in shaft diameter, that is, the variable " Diameter "assembly drawing will automatically change the variable" d " fragment, which will lead to the necessary change in its image.

When designing a fragment in the variable editor, you can specify the name of the assembly variable for an external variable. If later, when inserting a fragment in an assembly drawing, the system finds a variable with the same name, it will automatically be associated with the corresponding external variable of the fragment.

To automatically set relationships between the values ​​of fragment variables and variables of other fragments in the assembly, you can use the mechanism connectors

When working with a large number of external fragment variables, it is convenient to use configurations.

Configurations are a named set of values ​​of external document variables stored in a document and the 3D geometry corresponding to these values. In a 2D document, only the values ​​of external variables are stored in the configuration. More information about working with configurations is described in the “Configurations” section.

If configurations have been created in the 2D fragment document, then when inserting or editing a fragment, you can select one of the fragment configurations. All external fragment variables will automatically be assigned the values ​​stored in the selected configuration.

The name of the configuration to use can be set to a variable. If the value of this variable changes, the system will select the appropriate model configuration and change the values ​​of the fragment variables automatically.

Controlling the visibility of fragment drawing elements

A part drawing may contain an image that does not need to be included in the assembly drawing. Or it may be that, depending on the situation, we need to use one or another part of the drawing of the same part (for example, in one case we need a top view, in another case we need a front view). The visibility of fragment drawing elements included in an assembly can be controlled using layers or visibility levels. When using layers, two options are possible.

The first is to use the layer's own attributes ("Invisible when inserted into assembly", " Visible only when inserted into an assembly"). This method does not allow you to organize several options for depicting a fragment based on one drawing, however, it can be used to hide/show elements of the drawing of a fragment part, which are probably necessary in the drawing of the part, but should be absent in the assembly (or vice versa). For example, this could be the dimensions of the part, format, etc.

The second method is more flexible and can be used when positioning a fragment along the anchor vector. The snap vector parameters can specify how it is connected to the selected layers (see "Snap vectors"). Having created several reference vectors in the drawing with various options connections with layers, you can get several options (for example, views) of a part based on one drawing.

Controlling the visibility of elements of a drawing fragment using visibility levels is done by general rules, in the same way as for all other elements of the drawing. This method may require the use of external fragment variables: to control the visibility levels of the fragment drawing, external variables can be created in the fragment, which can be transferred to the assembly document to control the image of the part. The visibility levels of fragment drawing elements controlled by the values ​​of external variables, both when editing in the context of an assembly and when detailing, will be reflected in accordance with the values ​​of the variables in the assembly.

Removing invisible lines in an assembly drawing

One of the important advantages of T-FLEX fragments is the ability to remove invisible lines when creating an assembly from fragments. This allows, on the one hand, to create a complete drawing required part, and on the other hand, to “hide” those lines of this drawing that are covered by the image of other parts of the assembly drawing.

The area of ​​the drawing in which it is necessary to provide for the removal of invisible lines is specified using hatching. To remove invisible lines, you can use an existing hatch or create an additional invisible one (using the filling method - "Invisible"). In the hatching parameters, you must select the " Invisible lines ". In this case, the invisible hatch will hide objects with a lower priority. The visibility of the overlapped element is adjusted by setting the corresponding priority in its properties. If the fragment should cover the assembly lines, then the fragment should be set to a higher priority than those elements of the assembly drawings that it must overlap. If the assembly lines must cover the lines of the fragment, then you will have to create a hatch in the assembly drawing itself, and then set a priority for it that is higher than the priority of the corresponding fragment.

Let's look at removing invisible lines using the example of a drawing of a shaft and a bearing fragment. In the shaft drawing, you need to create hatching to remove invisible lines. After applying the fragment to the assembly, the image of the bearing fragment will overlap the image of the shaft. In order for the shaft image to cover the bearing lines, it is necessary to set the priority value of the bearing fragment less than the priority of the hatch outline for the shaft. This can be done immediately when drawing a fragment, and then when editing it.

After changing the fragment priority, you need to update the image by calling the command "RD: Refresh document windows" (by pressing ). The result will be the image shown in the last picture.

Binding to Fragment Elements

Although the lines and other elements of a fragment are not part of the drawing in which it is included, they can be used to create various assembly drawing elements. Simple lines of a fragment image (arcs and segments) can be used at any time if object snapping is enabled. So, you can outline the image lines of a fragment with new construction lines or build a dimension or other design element on them.

In addition to the fragment image lines, you can use fragment nodes. To enable the ability to use fragment nodes, you need to activate certain settings. In the team ":Set system settings" on the " Bindings " tab "checkbox must be checked"Allow bindings to\Fragment Nodes". This setting will allow you to create assembly drawing elements based on named fragment nodes or image line ending points. In this case, new nodes built from fragment nodes will be created in transparent mode.

If the image of a fragment is highly saturated with different elements, working in transparent mode can be somewhat difficult. In this case, you can disable the previous setting and switch to forced modes of creating the required nodes from the fragment:

1. In the command "N: Build node" you can create only those fragment nodes that are really needed for further work with the assembly.

2. Named fragment nodes can be created automatically when inserting a fragment, if in the system settings (command " :Set system settings", tab " Fragments ") the checkbox is checkedCreate named nodes automatically".

Creating an Assembly Bill of Materials

Creating a specification is one of the important stages of working with an assembly model. Working with specifications is described in detail in the section "Product structure, reports. Specification".

To automatically fill in the specification fields, it is necessary that the parts (fragments) of the assembly drawing contain a set of corresponding data. The data for the specification is specified in the fragment part document in the "Product Structure" window at any stage of work. When you include a fragment in an assembly, you can provide a way to use nested elements (other fragments) and their data in the assembly's product structure. This allows you to include information about nested fragments in the assembly product structure or add data from the product structure located in the fragment document. Setting the appropriate mode makes it easier to create BOMs for multi-level assemblies.

To obtain an assembly document specification, you must perform the following steps:

1. In the fragment document, fill in the data for the specification in the "Product Structure" window.

2. In the assembly document in the fragment parameters or in the " command:Inclusion in the product structure" (" Service|Reports/Specifications|Inclusion of fragments in the product structure") set the method for including a fragment in the product structure.

3. Using the command " :Create report/specification" you can generate an assembly specification.

Changes to the assembly drawing are automatically reflected in the specification. If necessary, an unlimited number of reports or specifications can be associated with an assembly drawing.

Detail drawings based on fragments

When creating an assembly, fragment drawings can be changed in accordance with the assembly parameters by changing the external variables of the fragments or the entire image with associative binding. The fragment drawing files do not change. However, if necessary, you can automatically obtain separate documents containing drawings of fragment parts with parameters corresponding to the assembly parameters. We will call such drawings detailed drawings. Detail drawings can be obtained for the entire set of parts that make up the assembly drawing. When you create a detail drawing, no connection to the original assembly drawing is maintained.

To obtain a detailed drawing, you need to use the optioncommands "FR: Create fragment" or "EFR: Edit fragment" or the command "Detailing" in the context menu for the fragment. After calling the command, a new document window will open, into which a copy of the fragment drawing will be loaded with the values ​​of external variables and associative links substituted from the assembly. The new drawing will be named “Part” with a serial number, for example, “Part 1”. This drawing will be defined by the system as new, that is, when you try to close it, the system will prompt you to specify a name for the drawing to save.

Typically, detail drawings are used to print drawings of parts that may be different from the original drawing of the fragment, for example, by changing assembly variables. In this case, it is not even necessary to save an electronic copy of the detail drawing. This is convenient if the parametric fragment used in the assembly contains a fully designed drawing and when creating detailing, the user instantly receives a set of new documentation for the required part.

Revealing fragments

The fragment applied in the assembly can be “revealed”. In this case, the fragment is deleted, and instead, copies of all visible elements of the fragment are created in the assembly drawing.

The system can expand selected fragments in two ways, turning them into a set of drawing elements, with or without the original constructions. In the first case, all parametric connections between the elements of the former fragment are saved and all the necessary construction lines are transferred from the fragment drawing to save the parametric connections of the drawing of the former fragment. In the second case, the fragment turns into a set of image lines built along free nodes.

A fragment containing nested fragments is expanded into the image elements and fragments it contains. After using the expand option, you can work with the resulting elements as usual, depending on their type.

If any elements (dimensions, construction lines, etc.) were created based on the fragment elements in the assembly drawing, then after expanding the fragment they will be re-linked to the elements created when expanding the fragment (nodes, construction lines and images).

Using Connectors

When creating assembly documents, there is often a need to link the parameters (variables) of inserted elements with the parameters of the elements to which the binding is made. For example, fitting a bearing to a shaft, tying a cap to a bearing, keys to a keyway, nuts to a bolt, inserting a screw or stud into a hole, etc. When inserting such elements, the user is required not only to set the basic dimensional parameters (diameter, length, etc.), but also to accurately position the inserted element relative to the existing one (select an anchor point and direction). One way to solve this issue is to use the “measurement” mechanism, which, however, often requires large quantity auxiliary actions. It allows you to significantly simplify the procedure for inserting elements into an assembly model and minimize the number of user actionsconnector mechanism.

The basis of this mechanism is a “connector” - a construction element designed to bind other elements to it. Essentially, the connector is an analogue of the binding vector or target binding LCS for 3D fragments. Its main difference from the anchor vector is that the connector is used to bind other model elements to it. So, for example, using the anchor vector we can apply to assembly drawing image of a nut. Let's say the bearing image should be linked to the shaft, then the connector should be linked to the shaft image (fragment).

In addition to the geometric position (the position of the origin of the coordinate system and the direction of the axes), the connector can store other information necessary to “connect” other elements to it.

Information in the connector is stored in the form of named values, which can be either constants or variables. The names of these values ​​are used to set the values ​​of the corresponding external variables of the fragments connected to them. For example, a connector located on the axis of a hole may have the depth and diameter of the hole as such parameters. When a pin is inserted into this hole, its diameter can be set automatically by the D value stored in the connector. This requires that the external variable that specifies the diameter of the stud also be named "D".

There are a number of nuances when connecting a fragment to a connector:

● The connector is a construction element and may not be visible in the main drawing. However, it must be selected when connecting a fragment to it.

● The connector may be located at a point that is not shown in the drawing.

● Sometimes it is convenient to connect an element to the connector that is located to the side of it. For example, when tying a cover to a bearing, it is convenient to select the lines of the bearing itself, lying on its periphery. In this case, the connector that lies on the bearing axis must be selected.

To solve these issues and increase clarity, the concept of “associated elements” was introduced, a list of which is stored in the connector. Associated elements are required to fully use the object snap mechanism when connecting to a connector. When you move the cursor to one of the image lines associated with the connector, the connector is automatically activated (highlighted on the screen) and the external variables of the fragment receive the corresponding values ​​taken from the connector. The 2D fragment is automatically recalculated with new variable values ​​and placed at the connection point with the appropriate orientation.

All libraries of standard T-FLEX CAD elements are already equipped with connectors and prepared for their use. For responsible external variables, the necessary named values ​​are preset for communication with connectors.

Composite document. Nested fragments

T-FLEX CAD has a mechanism that allows you to control the way links to other documents are stored (fragments, pictures, external databases, etc.). A T-FLEX CAD document can store links to external files (“external link”), or data from external files can be saved directly within a T-FLEX CAD composite document file (“internal link”). The same mechanism allows you to quickly transfer the assembly model to another location in the file system, pack the assembly model into one file with the possibility of subsequent unpacking.

To manage links in the system, a group of commands is used “ File|Build… " Working with commands of this group is described in the chapter “Links. Management of compound documents.”

Team " UL: Update links” reloads the data from the first-level external files included in the compound document.

Dimensions on assembly drawings can be divided into two groups:

1. The dimensions that must be made or controlled according to this assembly drawing are, as a rule, as-built dimensions.

2. Dimensions that are not subject to execution according to this assembly drawing and are indicated for greater convenience in using the drawing, these are, as a rule, reference dimensions.

The first group of sizes includes:

a) installation dimensions indicating the relative position
parts in products, these include installation gaps. Often mutual
the location of the parts is determined by the combination of their mating
surfaces, for example mating planes. Therefore, installation
Dimensions on assembly drawings may not be available;

b) dimensions of parts elements that are performed in the process
or after assembly, for example by machining after
welding, riveting, soldering, pressing;

c) the dimensions of the mating elements of the parts, which determine
nature of the connection (fit), for example, mating size with maximum deviations of the diameter of the cylinder and piston:

d) dimensions characterizing operational parameters
products and positions of individual structural elements; to them, for example
measures include the stroke of the piston, engine valve, and lever.

The second group of sizes includes:

a) overall dimensions defining the maximum external
(internal) outline of the product, such as the height, length and width of the product or its largest diameter;

b) installation and connection dimensions that determine the dimensions of the elements by which this product is installed at the installation site or connected to another product; these include the dimensions of the center circles on the flanges along which the holes are located, and the diameters of the holes for the bolts, the distances between the mounting holes, the connecting dimensions of the threads, etc.;

The drawings of assembly units indicate those dimensions that must be made and controlled according to a given assembly drawing, i.e. all executive dimensions, including dimensions for making permanent connections (riveting, welding, soldering, pressing). From the group of reference dimensions, they indicate installation, connecting, overall, and from the characteristic dimensions, some dimensions that determine the technical characteristics of the assembly unit, for example, lever arms and their travel. Note that some of the installation, connection and operational dimensions can be made according to the drawing during the assembly process. A drawing of an assembly unit should not contain those images that are given only to identify the shape and size of the elements of parts (these images are typical for drawings general view and are necessary only for the development of working documentation).

Dimensions on assembly drawings are determined by calculations, layout, technology requirements and operating conditions of the products. By assigning them, the designer thereby requires their exact execution during the assembly process or precise interconnection and coordination of all components.

Based on the assembly drawing of the product, the worker must correctly understand the principle of operation, the interaction of parts, then, using the main image and number, make sure that the required part has been received for the assembly, read the installation dimensions, understand how the parts are connected, find out the dimensions necessary for additional processing in the process assemblies, as well as technical specifications for testing, movement of parts, coatings, etc.

On assembly drawings of a product for all sizes of mating elements of parts, both moving and stationary, as a rule, instructions are given about the nature of the connection (fitting - tolerance range) and quality (accuracy class). The nominal dimensions relating to both the hole and the shaft are indicated, and to the right of the nominal dimensions a notation is given in the form of a simple fraction with the hole fit in the numerator and the shaft fit in the denominator. This information is necessary for the worker to ensure strict execution of the connection, as well as when repairing the product.

The designation of the fit (for example, on assembly drawings in connections) includes a nominal size common to both elements of the parts being connected - the hole and the shaft, followed by designations of the tolerance fields for each element starting from the hole. In this case, three forms of designation are possible: 0 14 H7/g6(preferred), 0 14 H7-g6, 0 14 H7/g6. These designations correspond to the following landing designation according to OST 0 14 HELL. By the position number of fasteners (in the drawing of the assembly unit) and by the designation in the specification, you can find out their diameter.

For assembly units that include one main (complex) part and several simple parts or standardized products (ball bearings, bushings, etc.) connected by pressing, flaring or other methods, it can be advantageous to combine the assembly drawing with the drawing of the main part. In such a combined drawing, in addition to the considered information necessary for assembly, all dimensions and other data for the manufacture and control of the main part are given. Separate drawings are produced only for the remaining simple parts. The designation and name of the main part are assigned according to general rules, and in the specification in the “Format” column they write BC (which means: “Without drawing”). The labor intensity of completing technical documentation for an assembly unit using this method is reduced by 20-60%, depending on the complexity of the main part.

ASSEMBLY DRAWINGS

Assembly drawing requirements

Rules for the execution and execution of assembly drawings are established GOST 2.109-73.

Assembly drawing(SB) - contains an image of the assembly unit and other data necessary for its assembly and control.

Text documents include:

Specification– a document defining the composition of the assembly unit.

The number of assembly drawings should be minimal, but sufficient for the rational organization of production (assembly and control) of products. If necessary, assembly drawings provide data on the operation of the product and the interaction of its parts.

The assembly drawing must contain:

Images of the assembly unit, while it is allowed to depict other components of the product in thin lines;

Dimensions – overall, controlled according to this assembly drawing, connecting, mating, installation, reference. It is allowed to use the dimensions of parts that determine the nature of the connection as reference dimensions;

Instructions for the use of permanent connections;

Position numbers of connected parts;

Technical characteristics of the product (if necessary).

The assembly drawing is made with simplifications. For example, the assembly drawing does not show small elements (chamfers, roundings, etc.).

The assembly drawing must contain:

a) an image of an assembly unit, giving an idea of ​​the location and mutual connection of the components connected according to this drawing, and providing the ability to assemble and control the assembly unit.

It is allowed to place additional schematic images of the connection and location of the component parts of the product on assembly drawings;

b) dimensions, maximum deviations and other parameters and requirements that must be met or controlled according to this assembly drawing.

It is allowed to indicate as reference the dimensions of parts that determine the nature of the interface;

c) instructions on the nature of the mating and methods for its implementation, if the accuracy of the mating is ensured not by specified maximum dimensional deviations, but by selection, fitting, etc., as well as instructions on making permanent connections (welded, soldered, etc.);

d) position numbers of the components included in the product; e) overall dimensions of the product;

f) Installation, connection and other necessary reference dimensions;

g) technical characteristics of the product (if necessary);

h) coordinates of the center of mass (if necessary) if they are not given in another design document, for example, on a dimensional drawing.

When specifying installation and connection dimensions, the following must be indicated:

Location coordinates, dimensions with maximum deviations of elements used for connection with mating products;

Other parameters, for example, for gears that serve as external link elements, are the module, number and direction of teeth.

On the assembly drawing it is allowed to depict moving parts of the product in an extreme or intermediate position with the appropriate dimensions. If, when depicting moving parts, it is difficult to read the drawing, then these parts can be depicted in additional views with appropriate inscriptions, for example: “Extreme position of the carriage pos. 5".

On the assembly drawing of the product it is allowed to place an image of border (neighboring) products (“furnishings”) and dimensions that determine their relative position (Fig. 30).

The components of the product located behind the furnishings are depicted as visible. If necessary, it is allowed to depict them as invisible.

If on the assembly drawing it is necessary to indicate the names or designations of the products that make up the “furnishings” or their elements, then these instructions are placed directly on the image of the “furnishings” or on the shelf of a leader line drawn from the corresponding image, for example: “Pressure machine (designation )"; "Oil cooler pipe (designation)", etc.

On an assembly drawing of an auxiliary production product (for example, a stamp, a jig, etc.), it is allowed to place an operational sketch in the upper right corner.

Assembly drawings should, as a rule, be made with simplifications that comply with the requirements of the standards of the Unified System of Design Documentation and this standard.

Products made from transparent material are depicted as opaque.

It is allowed on assembly drawings to depict components of products and their elements located behind transparent objects as visible, for example: scales, instrument needles, internal structure lamps, etc.

Products located behind a helical spring, shown only as sections of coils, are depicted up to the zone that conventionally covers these products and is defined center lines sections of turns (Fig. 31).

In assembly drawings, the following methods of simplified depiction of product components are used:

The sections depict undissected components for which independent assembly drawings are drawn up.

On assembly drawings that include images of several identical components (wheels, road wheels, etc.), it is allowed to make a complete image of one component, and images of the remaining parts - simplified in the form of external outlines.

A welded, soldered, glued and similar product made of a homogeneous material assembled with other products in sections and sections is shaded in one direction, depicting the boundaries between the parts of the product with solid main lines (Figure 35).

It is allowed not to show the boundaries between parts, i.e., to depict the structure as a monolithic body.

Moving parts of the product are depicted in extreme or intermediate positions with a line -.. -..-

It is allowed not to show:

(spring – center line). "pos. 3 – cover not shown).

Those parts of the product for which independent drawings are drawn up are depicted as uncut.

Seal - arrow.

Adjacent parts - with different shading or slope (on all sheets of the same part the shading is the same)

Elements less than 2 mm thick are blackened.

In permanent connections - single hatching or with a border.

It is allowed to depict parts on the drawing field for which there are no separate drawings

It is allowed not to show on assembly drawings:

a) chamfers, roundings, grooves, recesses, protrusions, knurling, cuts, braids and other small elements;

b) gaps between the rod and the hole;

c) covers, shields, casings, partitions, etc., if it is necessary to show the component parts of the product covered by them. In this case, an appropriate inscription is made above the image, for example: “Cover pos. 3 not shown";

d) visible components of products or their elements located behind the mesh, as well as partially covered by components located in front;

e) inscriptions on plates, branded strips, scales and other similar details, depicting only their outline.

Item numbers

In the assembly drawing, all components of the assembly unit are numbered in accordance with the item numbers specified in the specification of this assembly unit. Item numbers are placed on the shelves of leader lines drawn from the images of the component parts.

Position numbers indicate those images on which the corresponding components are projected as visible as a rule, on the main views and sections replacing them.

Position numbers are located parallel to the main one drawing labels are outside the image outline and grouped in a column or line if possible on the same line.

Position numbers are usually indicated on the drawing. once. It is allowed to repeatedly indicate item numbers of identical components.

The font size of item numbers should be one or two more numbers, than the font size adopted for the dimensional numbers on the same drawing.

Allowed to do general leader line with vertical arrangement of position numbers:

a) for a group of fasteners belonging to the same fastening point (Fig. 36). If there are two or more fasteners and, at the same time, different components are fastened with the same fasteners, then their number may be entered in parentheses after the corresponding position number and indicated only for one unit of fastening.

component part being cast, regardless of the number of these components

in the product;

b) for a group of parts with a clearly defined relationship, excluding different understandings, if it is impossible to draw a leader line to each component part (Figure 37).

In these cases, the leader line is drawn away from the component being fixed;

c) for individual components of the product, if it is difficult to depict them graphically, in this case it is allowed not to show these components on the drawing, but to determine their location using a leader line from the visible component and on the field of the drawing; in the technical requirements, place the appropriate indication, for example: ,Harnesses pos. 12, under the brackets, wrap with press span pos. 22".

Execution of certain types of assembly drawings.

It is allowed to place separate images of several parts on the field of the assembly drawing, for which it is allowed not to produce working drawings, provided that the clarity of the drawing is maintained.

An inscription is placed above the image of the part containing the position number and the scale of the image, if it differs from the scale indicated

in the title block of the drawing.

It is allowed not to issue drawings for:

Parts made from graded material, cut around the circumference, at an angle, around the perimeter

Surfacing, pouring

One-piece, glued, soldered, simple

Purchased

Specification

The specification is drawn up on separate sheets for each assembly unit, complex and kit according to forms 1 and 1a.

The specification is the main design document, determines the composition of the assembly unit, complex and kit and is necessary for the manufacture, completion of design documents and planning the launch of these products.

The specification includes the components included in the specified product, as well as design documents related to this product and its non-specified components.

The specification generally consists of sections, which are arranged in the following sequence:

documentation;

complexes;

assembly units;

standard products;

other products;

materials;

kits.

The presence of certain sections is determined by the composition of the specified product. The name of each section is indicated as a heading in the “Name” column and underlined. After the section, a reserve line or 2 is left.

- To the "Documentation" section" enter the documents (designation) that make up the main set of design documents for the product being specified.

- In the sections "Complexes"", "Assembly units" and "Parts" They introduce complexes, assembly units and parts that are directly included in the specified product. It is recommended to record the specified products in the order increasing classification characteristics (the noun comes first).

- In the section “Standard products”"record products used according to:

state standards;

republican standards;

industry standards;

enterprise standards (for auxiliary production products).

in alphabetical order of product names.

- to the section “Other products”"include products that are not used in accordance with the main design documents (technical specifications) with the exception of standard products. Products are recorded in similar groups; within each group - in alphabetical order of product names.

- To the section “Materials”"include all materials directly included in the specified product.

Materials are recorded by type in the following sequence: ferrous metals;

magnetoelectric and ferromagnetic metals;

non-ferrous, noble and rare metals;

cables, wires and cords; plastics and press materials;

paper and textile materials;

timber;

rubber and leather materials;

mineral, ceramic and glass materials;

varnishes, paints, petroleum products and chemicals;

other materials.

Within each type, materials are recorded in alphabetical order of names, and within each name - in ascending order of size or other technical parameters.

- To the section “Kits”" enter a list of operational documents, a list of documents for repairs and kits used according to design documents that are directly included in the specified product, as well as packaging intended for the product, and write them down in the following sequence:

List of operational documents;

List of documents for repairs;

Set of mounting parts;

Set of replacement parts;

Set of spare parts;

Set of tools and accessories;

Set of styling products;

Other kits (by the names assigned to them);

If the kit includes no more than three items, then the specific kit need not be compiled, and the products included in the kit must be written directly into the specification of the corresponding product in the “Kits” section. In this case, the name of the kit to which the items included in the kit belong product specification is written in the “Name” column as a heading and is not underlined. (Changed edition, Amendment No. 3).

The specification columns are filled in as follows:

a) in the “Format” column indicate the document formats, the designation of which is recorded in the “Designation” column. If the document is made on several sheets of different formats, then an “asterisk” is placed in the column, and all formats are listed in increasing order in the “Note” column.

For documents recorded in the sections “Standard Products”, “Other Products” and “Materials”, the column is not filled in.

For parts for which drawings have not been issued, the column indicates: warhead.

For documents published by printing, lithographic and similar methods in formats provided for by the relevant state standards for printing publications, a dash is placed in the column;

b) in the “Zone” column indicate the designation of the zone in which the position number of the recorded component is located (when dividing the drawing field into zones according to GOST 2.104-68).

c) in the “Items” column indicate the serial numbers of the components directly included in the product being specified, in the order in which they are recorded in the specification. For sections “Documentation” and “Kits” the column is not filled in;

d) in the “Designation” column indicate:

in the "Documentation" section - designation of the documents being recorded;

in the sections “Complexes”, “Assembly units”, “Parts” and “Kits” - designations of the main design documents for the products recorded in these sections. For parts for which drawings have not been issued, the designation assigned to them.

In the sections “Standard products”, “Other products” and “Materials” the column is not filled in. If design documentation has been issued for the manufacture of a standard product, in the column “Designation” indicate the designation of the issued main design document;

e) in the “Name” column indicate:

In the “Documentation” section, for documents included in the main set of documents of the specified product and compiled for the product, there is only the name of the documents, for example: “Assembly drawing”, “Dimensional drawing”, “Technical conditions”.

in the section “Materials” - designations of materials established in the standards or technical specifications for these materials.

f) in the “Quantity” column indicate:

for the component parts of the product recorded in the specification, their quantity per one specified product;

in the “Materials” section - the total quantity of materials for one specified product, indicating the units of measurement. It is allowed to write down the units of measurement in the “Note” column in close proximity to the “Quantity” column.

In the “Documentation” section, the column is not filled in;

g) in the “Note” column indicate additional information for planning and organizing production, as well as other information related to the products, materials and documents recorded in the specification, for example, for parts for which drawings have not been issued - weight.

For documents issued on two or more sheets of different formats, indicate the designation of the formats, preceded by an asterisk, for example: *) A4, A3.

After each section of the specification, it is necessary to leave several free lines for additional entries (depending on the stage of development, the volume of entries, etc.). It is also possible to reserve item numbers that are entered into the specification when filling out reserve lines.

It is allowed to combine the specification with the assembly drawing, provided that they are placed on an A4 sheet (GOST 2.301-68). In this case, it is placed above the main inscription and filled out in the same order and in the same form as the specification made on separate sheets.

For products of auxiliary production and single production of one-time production, it is allowed to combine the specification with an assembly drawing on sheets of any format established by GOST 2.301-68. The rules for the execution and circulation of such combined documents are established in industry standards. The combined document is assigned the designation of the main design document. The main inscription is carried out in accordance with GOST 2.104-68 (form 1).

The columns “Mass” and “Material” are filled in as follows:

a) in the “Weight” column indicate:

for parts for which drawings have not been issued - the mass of one part;

For materials - the mass of material for a given specified product;

b) in the column “Material” for parts for which drawings have not been issued, indicate the designations of materials established in the standards for these

Assembly drawing represent certain type design documentation, which contains graphic and text information about all the parts included in the composition of any product. According to the assembly drawings, as you can easily guess from the name itself, various components and assemblies are assembled.

One of the main requirements for assembly drawings is that there should be a minimum of them, but together they must provide for the entire assembly process and quality control of the finished product. In cases where this is necessary, the assembly drawings indicate data on how the interaction occurs various parts structures and assembly units.

One of the main purposes of an assembly drawing is to create a complete idea of ​​what composition the assembly unit has, as well as what its functional purpose is.

Based on assembly drawings, it is possible to create ready-made technical devices, both the simplest units and very complex mechanisms.

Assembly drawings give an idea of ​​how they are located relative to each other various parts machines and mechanisms, as well as how exactly they interact with each other.

All products on assembly drawings are shown only in assembled form.

Assembly drawings depict various sections, sections and standard types of products. Thanks to which it becomes possible to identify exactly what kind of device the assembly units have, as well as how the parts included in their composition are interconnected.

The basic rule for shading on sections and sections of assembly drawings is that it is done with lines of a certain thickness, directed in the same direction. In this case, the distance between them should be the same.

In cases where it is necessary to depict parts in contact with each other on sections or sections of assembly drawings, hatching at an angle of 45° is carried out with lines located counter to each other. In this case, it is also possible to change the distance between the dashed lines. In addition, you can perform hatching without changing the direction of the lines, but with a shift between them or changing the distances.

In cases where the width of sections on assembly drawings is less than two millimeters, they are not shaded, but blackened.

Parts such as handles, connecting rods, spindles, non-hollow shafts, keys, rivets, washers, studs, bolts and screws are shown uncut in longitudinal sections of assembly drawings. In other sections they are depicted as dissected.

Mandatory attributes of all assembly drawings are dimensions specified in order to characterize both the assembly or device itself as a whole, and those parameters that must be met both during its assembly and when monitoring individual parameters. These dimensions are divided into overall, installation, connection, installation and reference.

1) Using overall dimensions, parameters such as length, height and width, which are external, are displayed.

2) To correctly install a particular assembly unit, installation dimensions are used. They determine quantities such as center-to-center distances for screws, bolts, studs, etc.

3) Connecting dimensions are those that provide fastening of the products shown on the assembly drawings to other components and assemblies. It often happens that the connecting dimensions are also installation dimensions.

4) In order to correctly install parts in relation to each other, installation dimensions are used (for example, distances between axial and center lines).

5) A feature of reference sizes is that they are indicated only when dictated by necessity. It happens that on assembly drawings all available dimensions are reference.

In addition to dimensions, assembly drawings can also indicate such indicators as those dimensions that determine the extreme positions of individual moving parts of the structure, as well as those that are necessary for additional processing of its various components.

In addition to the listed dimensions, additional indicators may be indicated on the assembly drawings, such as: coordinates of the center of gravity of the product; dimensions for which additional processing of individual components will be carried out during the current assembly process; dimensions that determine the extreme position of moving parts of products.

Images of parts that appear on assembly drawings are assigned separate serial numbers, called positions.

With the help of positions, a connection is made between the textual information contained in the specification and images of individual parts. Positions make it much easier to find images of the required parts.

Position numbers are depicted on assembly drawings in fonts one or two numbers larger than the one used to display dimensional numbers.

To depict leader lines in assembly drawings, thin lines are used, and there are certain rules for drawing them and grouping them into columns and lines. An important requirement for them is that they should not overlap with each other. In addition, it is very desirable that they intersect as few images as possible in the drawings.