How to learn to read construction drawings. Drawing How to read turning drawings of parts

Read general view drawing- means finding out the purpose of this product, the structure and principle of its operation, getting a complete understanding of the shape, size and technical characteristics ah of the finished product and each part separately, i.e. determine from the drawing all the data for their manufacture and control.

When reading a general view drawing, find out the relative position components products, methods of connecting parts, as well as geometric shapes and sizes of all elements of the product.

Assembly, installation, repair or improvement of even simple assembly units are associated with the study of the design from a general drawing.

Since working drawings are developed based on the general drawing,

of parts, it must contain a sufficient number of images to allow such drawings to be made.

The task offered to students requires them to read a general drawing and use it to make working drawings of parts (as directed by the teacher).

1. Familiarize yourself with the contents of the main inscription placed in the lower right corner of the drawing. Determine the product name, drawing number, scale, etc. from the inscription. Often the name of the product says a lot about its purpose and operating conditions (for example, “Shut-off valve”, “Pneumatic vice”, etc.).

2. Familiarize yourself with the purpose and operating principle of the depicted product using the set of design documents attached to the drawing, in particular the explanatory note and technical specifications.

3. Study the images on the drawing: find out the location of the front view (main view); establish the number of main, additional and local views in which the drawing is made; determine which sections are used in the drawing (simple or complex); set the direction of the cutting plane for each cut; note the presence of sections, extensions, etc.

4. Familiarize yourself with the contents of this product; set the name of each part and consistently find each part in the drawing (on all views, sections and sections).

Determine from the found images geometric shape And design features details.

Clarification of the shape of each part is facilitated by the fact that in all sections and sections the same part is shaded with the same slope and the same distance between the lines.

5. Establish the nature of the connection of individual parts.

For permanent connections (welded, riveted, soldered, etc.), determine each element of the connection (for example, each individual weld).

For detachable connections, identify all fasteners included in the connection.

For moving parts, it is necessary to determine the process for their re-

displacement during operation of the mechanism (interaction of parts). It is necessary to establish which surfaces of the parts are mating and along what dimensions of the surfaces the connection is made.

Based on the general view drawing, the fit of the parts is determined, guaranteeing their interaction in the product.

6. Determine which moving surfaces of parts are lubricated and how this lubrication is carried out.

7. Establish the procedure for assembling and disassembling the product. In this case, it is necessary to highlight standardized and normalized parts for which working drawings are not drawn up.

Let's consider the procedure for reading a general drawing using the example of an assembly unit shown in Fig. 10.1.

From the main inscription it is clear that the drawing shows a plug valve on a scale of 1:1.

From the description, which is usually attached to general drawings for educational purposes, you can find out that a plug valve is one of the types of pipeline fittings and is intended to change the supply of liquid (gas) passing through a pipeline. Plug valves are installed where a quick change in the supply of liquid (gas) is required, since to fully open the valve it is enough to turn the plug at an angle of 90°.

The plug tap drawing contains three images. In place of the main view there is a frontal section, which shows the interaction of the main parts.

The faucet consists of a body 1 in which a conical plug 2 is installed (when turned, it changes the cross-section or completely closes the hole in the body). The plug 2 is pressed to the conical surface housing 1. Bushing 4 and stuffing box 11 (felt) seal the movable connection of parts 3 and 2.

In the view on the left, a local section is made, explaining the design of the connection between the housing and the cover with screw 5.

According to the specification (Fig. 10.2), we determine the composition of the parts included in the product “Plug tap”.

The product consists of 11 types of components, which include five original parts, five standard products and one material. All original parts are included in the product in a single copy. There is no drawing for part 5 “Gasket”, but the dimensions and shape of the part are explained in the specification.

Let's start getting acquainted with the original parts of the crane with the body. Studying the shape of this part in each view and comparing the views with each other, let us imagine an image of the body.

Since in the views the image of the body is partially covered by the image of the parts located inside or by the upper parts, it is necessary to supplement and combine into a single image all the available images of the body elements in the drawing.

The central part of the body has the shape of a truncated cone, which has pipes on the right and left. At the end of the right pipe there is a G1 cylindrical pipe thread. There is a flange at the end of the left pipe triangular shape with three through cylindrical holes Ø9. On top of the body there is a round flange with four threaded holes for attaching the cover.

The described shape of the body is comparable to the image in Fig. 10.3. The housing drawing is given in the appendix. 14.

Having dealt with the image of the main part (body 1), let's move on to studying the remaining parts (2, 3, 4). First, we will consider each of them in detail on the assembly drawing.

Plug 2 consists of a truncated cone with a radial hole and a cylindrical rod with a shank square section. Oval shape holes are determined by the view on the left, and square shape the shank can be read from the top view (Fig. 10.1). The shape of the plug is shown in Fig. 10.4 (a drawing of the plug is given in Appendix 15).

An image of cover 3 (Fig. 10.1) is shown in Fig. 10.5. Let's determine the shape of the cover elements from the assembly drawing and compare them with the image in Fig. 10.5 (a drawing of the cover is given in Appendix 15).

Rice. 10.4 Fig. 10.5

Determine the shape of the “Bulb” part yourself from the images available in the drawing (Fig. 10.1), then compare with the drawing given in the appendix. 17.

Every time you read a general view drawing, you must compare the drawing of a separate part with its image on the assembly drawing.

After the shape of the individual parts has been studied, it is necessary to establish how the parts are connected to each other and the possibility of movement of one part relative to another.

Thus, analyzing the relative position of the parts in Fig. 10.1, we determine that cover 3 is attached to the body using four screws 5.

On the cover 3 there is an oil seal sleeve 4, which ensures sealing of the felt packing 11. The oil seal is pressed against the cover using studs 9 and nuts 6.

The only moving part in this mechanism is the plug, which can rotate around its axis.

The valve in the drawing is shown in the open position.

If it happens that you are faced with the acute question of how to read drawings, and how to do it professionally and correctly, then most likely you will have to spend some time learning. A long path will be laid out before you in the form of reading a huge amount of often unnecessary literature, clicking on Internet links to textbooks, and the like.

A short version of how to learn to read drawings is presented in direct work with drawings under the guidance of an experienced engineer. For some people who are at least a little familiar with the construction field, familiarization with GOST standards, the electronic version of drawing up drawings or the self-instruction manual “Drawing for Dummies” will be sufficient. The main thing for a correct understanding of the drawing remains the same indicator - to have excellent spatial imagination, otherwise no amount of knowledge and experience will bring the desired result.

The ability to read blueprints is required for a number of construction professions: mechanics, estimators, masons, concrete workers, sometimes assemblers, welders and so on. To understand how to read drawings correctly, you first need to work directly with them. If you do not have the appropriate higher education in industrial or civil engineering, then to read a drawing you need to know the established standards, rules, conventions and simplifications specific to the area you are interested in (detail drawing or construction drawing country house). General rules Helping you understand the essence of how to learn to read drawings are:

• Familiarization with the title inscription of the drawing. It is its study that allows you to find out what material the depicted part is made of, its name and the scale of the drawing.
• Designation of images that served as a prototype for the presented part of the drawing.
• Carrying out analysis of the drawing image. It is the representation of the shape of a product or part that helps to better understand the essence of the data entered into the drawing. If you can’t recreate the entire part in your imagination, try to divide it into several parts and imagine their geometric shape.
• When you imagine a model of a product or object, you can already accurately study its dimensions (exact size) in the drawing.

Studying the drawing helps you get acquainted with the name of the product, how many parts are needed for its manufacture, calculate the scale and dimensions of the product, its weight, carefully review the details depicted there, which help to more accurately imagine the future configuration of the product already in finished form, taking into account all necessary requirements and standards.

To always have access to information on standardization and technological requirements necessary specifically for your chosen industry (house construction, pipeline construction, manufacturing of parts, structures, etc.), it is worth having a reference book or drawing textbook for personal use containing this information. You can also print data from the Internet so you always have it at your fingertips.

To summarize all of the above, you should start reading the drawing by familiarizing yourself with all its types, rules and methods for applying products on paper planes various shapes and size. Remember symbols and the standards necessary for the correct maintenance of the drawing during its preparation.

Reading blueprints is a required skill and a requirement for employment as an engineer of any qualification. This document is the main component of every project, without which neither the development of an oil and gas field nor the construction of a residential building will begin. For successful work with this documentation, the employee must have knowledge in the field exact sciences and have some drawing skills. In this case, reading the drawings will not cause difficulties.

Design organizations provide the operating company with several copies of documentation sets. One of them is a working option for a development company, intended for proper organization work of engineering staff directly on site.

Reading construction drawings allows you to determine the purpose of a building, its exact dimensions, the location of equipment, and the types of structures and materials. Here the designed object is depicted in three versions: facade, plan and sections (longitudinal and transverse). When examining the image of the facade you can see general form building and the height of all elements relative to floor level. This information can be read on the marks placed to the left of the main picture. The location of the entrance and exit, the number of rooms and their purpose, as well as the size and thickness of the partitions are clearly visible.

When designing a residential or industrial buildings, during the development of gas and oil fields, at the first stage, a master plan for the construction site is developed. Reading the general plan drawing gives general idea about this site. Here the layout of buildings, structures, as well as possible natural objects falling within the development area is schematically depicted. If there is an artificial embankment of the territory, the drawings show its section indicating the dimensions and material of the embankment.

In addition, for dangerous and potentially dangerous objects, sections of ITM Civil Defense Emergency Situations (engineering and technical measures of civil defense, measures to prevent emergency situations) and fire safety ( fire safety). For this purpose, general plan drawings are used, which indicate areas of possible damage, their sizes and the location of the accident (pressure pipeline rupture). A detailed reading of the drawings of these sections allows you to plan and timely carry out the necessary rescue measures, since the access points for special fire equipment and personnel evacuation routes are indicated here.

The images contain information about the types of pipes, their diameters, wall thickness, as well as the number and types of valves and adapters.

To ensure that reading the drawings gives a complete picture of the object being designed, a system of abbreviations and symbols is used, which, together with the requirements and standards for development, is regulated state standards RF according to the ESKD system.

Everything that was created by humanity at all stages of its development, all the brilliant thoughts that found their embodiment or remained the dreams of designers - one way or another, were presented in the form of drawings. Just as a literary text conveys the writer’s fantasies, so a drawing captures what came into the engineer’s mind and brought it closer to reality.

Rice. No. 1 “Example of drawings of the Eiffel Tower. France"

Today, all drawings are created using uniform rules and GOSTs, which makes them easier to read. Learning to read drawings of metal structures is not at all difficult, so if you decide to connect your hobbies or professional activity with the embodiment of metal structures, it is worth familiarizing yourself with general information on this issue, and then move on to the practice of independent reading.

KMD drawings, which are a detailed schematic representation of a metal structure, are developed taking into account certain rules set out in documents such as:

SNiP ( Building codes and rules),

SPDS (System requirements project documentation for construction),

ESKD ( one system design documentation).

Drawings of this kind include a set of data that you can use for production - marking, processing, welding and installation of metal structures.

Rice. No. 2 “Production of metal structures”

Before you start learning how to read drawings, it is advisable to independently refer to the above documents. Don’t forget to learn all the relevant GOSTs; knowledge of them will more than once help you quickly navigate reading the drawing. In addition, when creating any design drawing, special symbols are used.

Rice. No. 3 “Example of KM project diagram”

CM drawings are usually provided with an explanatory note, which sets out in text form the results of the calculations and decisions made, which justify these calculations. At the same time, the explanatory note contains technical and regulations, which were used to create the drawing and reference to GOST standards. This note is intended to make the diagram easier to read.

Rice. No. 4 “Example of KM project nodes”

A complete KMD project is developed according to KM and is a set of a title page with general data, statements, drawings of installation diagrams, drawings of assembly units and drawings of sending elements. At the customer’s request, the project may include: separate drawings of parts, 3D diagrams, special statements, etc.

Rice. No. 5 " Title page KMD project"

In the installation diagram you will see joints and assemblies, welded or bolted connections, which will be performed during installation. Text comments can also be given here. Also here you will find a list of shipping elements along with design diagrams or links to the drawing, so you will immediately understand which specific drawing each element belongs to. Drawings of dispatch elements are arranged in groups on a sheet. Thus, the sheet may contain drawings of elements that do not require assembly or only a structure from a bent profile.

Rice. No. 6 " Wiring diagram KMD project"

When developing diagrams of metal structures, the scale is chosen that allows you to make the drawing most understandable or easy to read, so you should not have problems understanding a professionally drawn up drawing. Please note that structures such as beams and columns can be drawn without observing scale, but maintaining relative position parts and holes.

Rice. No. 7 “Example of assembly drawing, KMD project”

After you have read the documentation of the drawings, you need to check the symbols and you need to know well how a particular product is designated. Rivets, holes, nodes, types of material used - all this has a letter, number or graphic designation, so it is better to consult the table if you do not already have sufficient experience in reading drawings.

Take your time, check all the values. The drawings were originally made for ease of reading and understanding, so if you take a few minutes to think about them, the further reading process will be much easier.

Everyone good day! I immediately apologize for writing posts so rarely (I’ll try more often 😛). But as they say, less is more. And today we’ll talk about reading mechanical engineering drawings, as well as various symbols.

Many of you probably think that Andryukha (who didn’t know this was me 😆) lost his mind and became read blueprints, this is not a book!?!? Yes, sure design drawings not a book, but much more complicated, and here it is necessary not only to know the alphabet but also to have special knowledge as an engineer. By the way, if anyone still doesn’t know how to become an engineer, read it.

I think that experienced engineers and even senior students of mechanical engineering and engineering specialties are already familiar with the term reading drawings firsthand. Okay, enough of this boring summary, especially since I will try to present the material as simply and interestingly as possible so that you don’t get bored while reading. So…

Reading mechanical engineering drawings for aspiring engineers.

Begin read the drawing, first having studied the purpose of the part, namely which group it belongs to. This can be anything, for example, a body of rotation (shaft) or a housing part (crankcase, for example) Assembly drawing unit (gearbox, motor, etc.). But today we will look at a drawing of the type of body of rotation and this is a shaft. I chose this part because I think it is the simplest both in design and in manufacturing, this is especially important to consider when reading drawings for novice engineers.

Basic rules for reading drawings (order).

Perhaps the main rule is to slowly study the design documentation and, in order, begin to absorb the information from the drawing that the design engineer wanted to convey to us. Only after this we begin to actually read the drawing.

Requirements for the cleanliness of part surfaces.

So, what do we see in the drawing of this shaft? Exactly! I have highlighted the roughness designation in red. Ra from 0.8 to 1.6. Units this parameter(microdistrict).

Why did I decide to consider this particular parameter first, you ask? This is the very first thing that is worthy of your attention, now I will explain why. The roughness indicated in the drawing determines which final view you need to perform processing on the part in question. For example, if we take this drawing specifically, then surfaces where Ra is 0.8 and 1.6 microns need to be polished or applied lathe for hard turning (after undergoing heat treatment or as it is also called hardening). Even probably Ra 0.8 is most likely polishing.

Yes, I almost forgot in the upper right corner of the drawing there is a roughness designation Ra 6.3 (v). This is called unspecified roughness of the part in the drawing. You'll probably think - well, if it's not listed, why the hell is it necessary? Well, you must agree that if you put roughness on each surface on a drawing of a part, then it won’t be a drawing, but solid roughness icons :) Well, in short, you understand :) Wherever the surface roughness is not specified, it should be no more than 6.3 microns.

Remember! Always start reading drawings by determining the cleanliness of the surfaces on the finished part, or more simply, the roughness.

Designation of cuts in the detail drawing.

In this section, we'll touch on section drawings in a part drawing. Yes, yes, you heard right exactly the cuts, everything here is actually simple. After all, this is a combination of analysis of different designations and parameters of various technical characteristics. Oh how I wrapped it up :). Of course, initially you might think that this is not a birthday cake to cut), okay... Actually, we see the letters A And B which stand near the vertical spaces (well, if you can call them that, for example, I call them that) above and below the arrows. These spaces indicate the start and end points of the cut. Imagine that the shaft is a sausage stick and you need to make two cuts to make sandwiches. You take a knife and cut in two places A-A and B-B. I’m talking about sausage 🙂 it’s probably time to go have a snack.

And when we made two cuts we will be able to see what is inside (or the cross-sectional plane) of the sausage TFUUU...YOU the shaft of course :). It's not exactly time for a snack.

What we will see in the section is shown in a large rectangular frame at the bottom of the drawing - these are the views cuts A-A and B-B. In our drawing these are just two keyways, nothing interesting or complicated.

It is worth saying that these are simple sections shown, but they are also quite complex with a broken contour, sometimes there can be several breaks, although the principle of appearance and designation is the same.

Designation of extension elements in drawings.

Let's continue reading mechanical engineering drawings with the study of notation. In this drawing we see. Yes, there are recesses on this part, which are not possible to indicate on the main view, since they will be too small and invisible to the human eye. For this reason, process and design engineers came up with the idea of ​​placing these elements in a separate area of ​​the drawing. Such elements are simply called - callouts. You should not pay special attention to this parameter since these are basically always standard grooves and recesses (chamfers). Be careful, it happens that such a callout may show an original groove that can become quite big problem in the manufacture of parts and even design special tool to obtain the required groove geometry. Well, that’s a different story :)

Detailed elements of the drawing are not worthy special attention, but under no circumstances should we forget about them

Technical requirements of the drawing.

Moreover, pay attention to the free space in the drawing (bottom right), it’s empty. Well, it’s just that I chose such a bad drawing, forgive me :) And usually they are located there technical requirements to the details, namely:

• Hardness of the part (and sometimes the workpiece)
• Unspecified maximum deviations and tolerances
• Requirements for untreated surfaces
• Hardness of the part after heat treatment
• The symbol "*" which usually denotes the size for reference.
• Various special requirements for the part (everything that comes to the designer’s mind).

Well, that's probably all for today. , both mechanical engineering and other areas of production, the science is not at all complicated and consists of a body of knowledge that you will receive after completing the relevant educational establishments Colleges and universities, and you will learn to read drawings quickly and correctly when you work in production and gain experience.

By the way, I have my own YouTube channel and here is a video on how to read drawings correctly. Look to secure the material.

Good luck to everyone! Press the buttons at the bottom of the article and this will be your thanks to the author, that is, me :)!

Thank you for your attention! Bye!