Phased execution of the valve assembly drawing. Assembly drawing. training sketches of assembly parts Assembly drawing shut-off valve acid-proof version 2

1. Drawing design 1. 1. Main inscriptions. The form of the main inscriptions The main inscriptions are determined by GOST 2. 104 68, which establishes their shapes, sizes, the procedure for filling in the main and additional columns. Title blocks are located in the lower right corner of the drawing. On sheets of A4 format, the main inscriptions are located only along the short side 1. 2. Procedure for filling in the main inscriptions In the columns (column numbers are indicated in brackets), the main inscription indicates: in column 1 - the name of the product and the name of the design document, if it has been assigned a cipher; in column 2 - the designation of the document; in column 3 - the designation of the material (the column is filled only in the drawings of the parts); in column 4 - the letter assigned this document(for educational drawings the letter "U");

O-rings The fastening of the soft O-rings to the shut-off valve is carried out by means of a nut with a washer. At constant temperatures, a metal ring can be pressed into the body of the body by pressing (a). With frequent temperature changes to ensure long term valve service sprinkling of rings made of copper alloys is carried out by deformation of the body or ring, made in the form of a double-sided or one-sided dovetail (b). Fastening of sealing rings on the thread (a) is used for increased or high hardness of the metals of the rings that cannot be expanded. In these cases, the ring is also attached by deforming the metal of the body itself or the shutter (b).

Valve. The valve attachment to the spindle head must allow free rotation of the valve. For valves with small passages (up to 50 mm in diameter), a spindle crimp can be used. wire clip wire ring fastening the spindle head in the valve slot

Valve mounting options for large bore valves are shown in the figure below. The direction of movement of the valve in the body and the elimination of its displacement or misalignment is achieved using three or four upper or lower guide ribs.

The stuffing box seals in the fittings between the stem and the bonnet are made with soft packing. Compression of the packing is created by a union nut, a threaded bushing (Fig. A, b) or a stuffing box cover (Fig. C, d). The stuffing box cover is fastened with studs, T-head locking bolts (Fig. C) or hinged bolts (Fig. D). In fig. a is shown packing from a hemp or linen cord, in fig. b - packing from separate rings (asbestos plate, leather, rubber, etc.). The union nut and the stuffing box are shown in the assembly drawings in the raised position. a c b d

Flywheels. The methods for attaching the handwheels to the spindle are shown in the figure below. For fittings of small passages, riveting is allowed instead of fastening the nut.

Grinding wheel exit grooves. Grinding allows you to get precise surfaces of the parts. The edges of the grinding wheel are always slightly rounded, therefore, the groove for the grinding wheel exit is made in the place of the part where the presence of a shoulder remaining from the edge of the grinding wheel is undesirable. Such a groove in the drawing of the part is depicted in a simplified manner, and the drawing is supplemented with an extension showing the profile of the groove. The types, shape and dimensions of the grooves are set by GOST 8820-69. The defining dimension for grooves on the surfaces of revolution is the surface diameter d. The dimensions of the grooves are not included in the dimensional chains of parts.

Grinding on the outer cylinder (A) Grinding on the inner cylinder (B) db External grinding d 1 Internal grinding d 2 RR 1 Up to 10 1 1, 6 d - 0.3 d + 0, 3 0, 5 0, 2 Up to 10 Sv .10 to 50 2 3 d - 0.5 d + 0.5

Grooves for metric threads. A groove is made at the end of the thread to exit the tool and obtain a full profile thread along the entire length of the rod or hole. In the drawings, the details of the groove are depicted in a simplified manner and the drawing is supplemented with an external element on an enlarged scale.

External thread (B) Internal thread(D) Thread pitch brr 1 D 1 Thread pitch b RR 1 d 2 0, 5 1, 6 0, 5 0, 3 d - 0, 8 0, 5 2, 0 0, 5 0, 3 d + 0, 3 0, 6 1, 6 0, 5 0, 3 d - 0, 9 0, 6 0, 7 2, 0 0, 5 0, 3 d - 1, 0 0, 7 0, 75 2, 0 0, 5 0 , 3 d - 1, 2 0, 75 3, 0 1, 0 0, 5 d + 0, 4 0, 8 3, 0 1, 0 0, 5 d - 1, 2 0, 8 1, 0 3, 0 1, 0 0, 5 d - 1, 5 1, 0 4, 0 1, 0 0, 5 d + 0, 5 1, 25 4, 0 1, 0 0, 5 d - 1, 8 1, 25 5, 0 1, 6 0, 5 d + 0, 5 1, 5 4, 0 1, 0 0, 5 d - 2, 2 1, 5 6, 0 1, 6 1, 0 d + 0, 7 1, 75 4 , 0 1, 0 0, 5 d - 2, 5 1, 75 7, 0 1, 6 1, 0 d + 0, 7 2, 0 5, 0 1, 6 0, 5 d - 3, 0 2, 0 8, 0 2, 0 1, 0 d + 1, 0 2, 5 6, 0 1, 6 1, 0 d - 3, 5 2, 5 10, 0 2, 5 1, 0 d + 1, 0 3, 0 6, 0 1, 6 1, 0 d - 4, 5 3, 0 10, 0 3, 0 1, 0 d + 1, 2

Part Measurement A wide variety of measuring tools are used to measure parts. Consider the techniques for measuring parts using the simplest tools such as a steel ruler, vernier caliper, caliper and internal gauge.

Measuring with a vernier caliper A caliper is the most common measuring tool that allows measurements to be made with an accuracy of 0.1 mm. They can measure the diameters of the rollers, the diameters of the holes, the width of the grooves and slots, the depth of the holes and various recesses, etc. The barbell compass consists of two main parts (Fig. 18): a ruler (bar) and a frame that encloses the ruler. The ruler has a millimeter scale. The frame has a scale called vernier. This scale has 10 divisions. A narrow ruler depth gauge is rigidly attached to the frame. The frame with a depth gauge can move freely relative to the rod, and can also be fixed in any position with a clamping screw. Both the rod and the frame have two jaws each, allowing external (lower jaws) and internal (upper jaws) measurements to be made (Fig. 19). In any position of the frame relative to the rod, the distance between the working upper and lower jaws is equal to the length of the extended part of the depth gauge. To establish the size measured with a caliper, you need to read along the ruler the number of whole millimeters that fit to the left extreme division of the vernier (zero stroke of the vernier). Then determine which order of the vernier stroke coincides with the stroke of the ruler, which corresponds to the number of tenths of a millimeter. In our example, the relative position of the ruler and vernier scales highlighted in Fig. 18, corresponds to the size 22.7 mm.

Measurements with a bore gauge and a caliper The diameter of a hole located deep inside the part is measured with a bore gauge with an accuracy of 0.5 mm. The distance between the feet of the bore gauge is determined using a steel ruler. In cases where it is impossible to remove the caliper without knocking down its installation, the wall thickness flew (with an accuracy of 0.5 mm) can be measured, as shown on the right. In this case, the legs of the calipers move apart slightly more than the thickness of the measured wall, for example, by 25 mm. Having now measured the distance between the legs of the calipers, "subtract from the obtained value added to the wall thickness of 25 mm, that is, a = 37 25 = 12 mm. To measure the center-to-center distance of holes of the same diameters, use a caliper or an internal gauge, applying them to the walls of the holes. The required distance will be equal to the sum of the measured distance and the diameter of one of the holes. If the diameters of the holes are different, then the half-sum of the diameters must be added to the distance between the nearest walls of the holes. The height of a part can be measured using two rulers.

To determine the radii of the curvature of the protrusions and depressions of the part, use the templates of the radius gauges (Figure 22, a). The set of radius templates is enclosed in a metal casing. On one side of the casing, templates with rounded protrusions are fixed, intended for determining the radii of the valleys, and on the other side, templates with the same valleys for determining the radii of the protrusions. The size of the radius is indicated on each template. Larger rounds, as well as flat rounds, can be made using an imprint on the paper, by overlaying it on the rounded part of the part and crimping or outlining the rounding contour with a finely sharpened pencil. With the help of a compass, the radius of the rounding is determined. The resulting size is rounded to the nearest normal radius in accordance with GOST 6636 69. Elements with threads are often found in details, for the measurement of which special templates are used, called thread gauges. They are a set of metal plates with projections that match the thread profile. On the casing of the thread gauge for metric threads, M 60 ° is indicated (Fig. 22 b), and for pipe D 55 °. Measuring the thread pitch consists in selecting a template, the teeth of which completely enter the troughs between the threads. Then, using a vernier caliper, the outer diameter of the thread of the rod (nominal thread diameter d) or the diameter of the cut from the hole along the protrusions (the inner diameter of the thread –d 1. , 75. According to the tables of ST SEV IBI 75, we determine the thread: M 22 x0, 75. In the absence of a thread gauge, the technique shown in Fig. 23 is applied. In this case, the thread is painted with a soft pencil lead and rolled on paper. A / n, where A. is an arbitrary distance between several strokes; n is the number of distances between strokes in size A, and n is less by one number of strokes.

Stage I, the required number of species is determined, drawing the contour of the part without observing the scale, but adhering to the proportions

Valve. Drawing general view... An example of a general arrangement drawing Dimensioning on a general arrangement drawing On educational drawings, dimensions are put down in font No. 5, and position numbers in fonts No. 7 or No. 10. The main inscription is the same as on sketches 55 x 185 - form No. 1. In educational drawings general types, the following dimensions should be applied: 1. Overall dimensions that determine the largest dimensions of the product in terms of length, width, height. 2. The dimensions of the mating surfaces (along which the parts of the assembly unit are in contact), including the threaded surfaces. 3. Installation dimensions by which this product is installed at the installation site. 4. Constructive and calculated dimensions due to the peculiarities of the work of the part in the unit. Characteristics of gears, springs, center distances, modulus, etc. and other parameters required by the detailing engineer. Free dimensions in general views are not applied, since these dimensions are taken directly from the drawing, taking into account the scale. General arrangement drawings are not production drawings. 5. Connecting dimensions. Dimensions that determine the elements by which this product is attached to another. These dimensions include: a) diameters of holes for fasteners; b) dimensions of connecting threads, etc.

Figure 1.22 shows an assembly drawing of a valve, the body of which and some parts are made by casting. The valve specification (first sheet and following) is shown in Figures 1.23 and 1.24.

Figure 1.25 shows an assembly drawing of a valve with a welded body; the flywheel of this valve is a reinforced product. The valve specification is shown in Figure 1.26.

Drawings of valves with a conical plug are shown in Figures 1.27 and 1.29, and the specifications for them are shown in Figures 1.27 and 1.30, respectively. In the first case, the sealing force on the plug is created by the gland sleeve using bolts, and in the second case, by the spring.

Figure 1.32 shows a drawing of a valve with a ball plug. Its specification is shown in Figure 1.31.

Figure 1.12 - Drawing of the assembly unit ²Spindle²

Figure 1.13 - Working drawing of the part ²Spindle²

Figure 1.14 - Working drawing of part ² Valve ²

Figure 1.15 - Drawing of a welded assembly unit

Figure 1.16 - Drawing of a reinforced product

Figure 1.17 - Cover. Working drawing

Figure 1.18 - Union nut. Working drawing

Figure 1.19 - Handle. Working drawing

Figure 1.17 Valve body. Working drawing

Figure 1.21 Valve body. Working drawing

Figure 1.22 - Valve. Assembly drawing.

Figure 1.23 - Valve. Specification

Figure 1.24 - Valve. Specification. Sheet 2

Figure 1.25 - Assembly drawing of a valve with a welded body

Figure 1.26 - Valve. Specification

Figure 1.27 - Cork valve. Specification

Figure 1.28 - Cork valve. Assembly drawing

Figure 1.29 - Crane. Assembly drawing.

Figure 1.30 - Cork valve. Specification

Figure 1.31 - Ball valve. Specification

Figure 1.32 - Ball valve. Assembly drawing

CONTROL QUESTIONS

1. Formulate the definition of the assembly drawing.

2. What dimensions are applied on the assembly drawing?

3.How to choose the number of images and the main image on the assembly drawing?

4. Why do you agree on the dimensions of the mating surfaces before making the assembly drawing?

5. What detail does the main image start with?

6. List the allowable simplifications and conventions on the assembly drawing. What is their purpose?

7. In what position are the valve spool and valve plug shown?

8. What does it mean to “read” the assembly drawing?

9. What is the purpose of the specification?

10. What is meant by the position of the part?

11. Give the definition of an assembly unit.

Stage 1- placement of images of the assembly unit in terms of overall dimensions (Fig. 1) on the A2 format.

Stage 2- an image of the body in size with the necessary cuts (Fig. 2).

Stage 3- image of the spindle (stem) and valve (Fig. 3).

Stage 4- a picture of the cover and the gasket between the body and the cover (Fig. 4).

Stage 5- image of the union nut, bushing and packing ring (Fig. 5).

6 stage- image of a flywheel with a washer and a nut and the limiting position (stroke) of the stem (Fig. 6).

7 stage- shading of all parts falling into the cutting plane (Fig. 7).

8 stage- drawing dimensions, leader lines for drawing position numbers, filling in the main inscription (Fig..8).

9 stage- drawing up a specification (Fig. 9).

10 stage- assignment of position numbers in accordance with the specification (Fig. 10).
























For independent work, the student is invited to complete a drawing of a complex part with a machine tool on a computer.
/ 1 / ch. 55, / 2 / ch. 22.

Section 3. Drawings and diagrams by specialty

When drawing a drawing, buildings are guided by general rules execution of construction drawings provided for by SPDS standards and GOST ESKD.

The building in the plan is dissected by center lines into a number of elements. The longitudinal and transverse axes that determine the location of the main supporting structures (walls and columns) are called coordination axes.

Coordination axes are applied to images by thin dash-dotted lines with long strokes. The axes are designated with Arabic numerals and capital letters of the Russian alphabet (except for letters: E, 3, Y, O, X, Ts, Ch, Sh, L, L, B) in circles with a diameter of 6 ... 12 mm. Omissions in digital and alphabetic (except for those indicated) designations of the coordination axes are not allowed.

To mark the axes on the side of a building with a large number of them, Arabic numerals are used.

To mark the axes on the side of the building with a smaller number of them, the letters of the Russian alphabet are used.

The axes of the elements located between the coordination axes of the main supporting structures may be marked with a fraction (B / 1; B / 2; 1/1, etc.).

The sequence of digital and letter designations of the coordination axes is taken according to the plan from left to right and from bottom to top.

The designation of the coordinate axes, as a rule, is applied to the left and lower sides of the building plan. If the coordination axes of the opposite sides of the plan do not coincide, the designations of these axes at the points of divergence are additionally applied on the upper and right sides.

The distance between the coordinate axes in the plan is called a step. The span is the distance between the coordination axes of the building in the direction that corresponds to the span of the main supporting structure of the floor or covering.

The height of the floor is taken as the distance from the floor level of the given floor to the floor level of the overlying floor, and the height of the upper floor is also determined, while the thickness of the attic floor is conventionally assumed to be equal to the thickness of the interfloor floor.

In single-storey industrial buildings, the height of the storey is equal to the distance from the floor level to the lower edge of the roof structure.

The sizes of steps, spans, heights of floors should be taken equal to the enlarged module. The dimensions of the structural elements of the building must be multiples of the main module. The size of the main module M for the coordination of dimensions is taken as a size of 100 mm (1 decimeter). The enlarged modules 6000, 3000, 1500, 1200, 600, 300, 200 mm denote respectively 60M, 30M, etc.

When dimensioning in the drawings, the dimension line at its intersection with extension lines, contour lines or center lines is limited by serifs in the form of thick main lines 2 ... 4 mm long, drawn with an inclination to the right at an angle of 45 ° to the dimension line, while the dimension lines should protrude beyond the extreme extension lines by 1 ... 3 mm (Fig. 3. 1).

When applying the dimension of the diameter or radius inside the circle, as well as the angular dimension, the dimension line is limited by arrows. Arrows are also used when dimensioning radii and internal fillets.

Level marks of structural elements, equipment, etc. from the reference level (conditional "zero" mark) are designated by a conventional sign (Fig. 3.2) and are indicated in meters with three decimal places separated from an integer by a comma.

The "zero" mark, taken, as a rule, for the surface of any structural element of a building or structure located near the planned surface of the earth, is indicated without a sign; marks above zero - with a "+" sign, below zero - with a "-" sign.

On views (facades), sections, sections, marks are placed on extension lines or contour lines (Fig. 3.3).

On the plans, marks are applied in rectangles (Figure 3.4).

On the plans, the direction of the slope of the planes is indicated by an arrow, above which, if necessary, the slope is indicated in percent (Fig. 5) or in the form of the ratio of height and length (for example, 1: 7). The slope designation is applied directly above the contour line or on the shelf of the leader line. The title block is located in the lower right corner.

The main inscriptions and frames are made with solid main and solid thin lines in accordance with GOST 2.303-68.

In the columns of the main inscriptions (the numbers of the columns on the forms are shown in circles) indicate:

· In column 1 - designation of the document; (uppercase font, size 5);

· In column 2 - the name of the work, product (uppercase font, size 5);

· In column 3 - the name of the task (uppercase font, size 5);

· In column 4 - the name of the images placed on this sheet (uppercase font, size 5);

In column 5 - designation of the material of the part (the column is filled out only on the drawings of the parts; lowercase font, size 5);

· In column 6 - letter "U" (training drawings);

· In column 7 - the serial number of the sheet (pages of a text document in case of double-sided registration). On documents consisting of one sheet, the column is not filled;

· In column 8 - the total number of sheets of the document (a set of drawings, explanatory note, etc.). On the first sheet of a text document with double-sided design, indicate the total number of pages;

· In column 9 - group No. (lowercase font, size 5);

· In column 10 - from bottom to top - "Student" (lowercase font, size 3.5).

· In columns 11, 12,13 - respectively, surname, signature, date;

· In column 14 - the estimated mass of the product shown in the drawing, in kilograms without indicating the units of measurement;

· In column 15 - image scale in accordance with GOST 2.302-68.


Fig. 3. 1
Rice. 3.2
Figure 3.3

Fig. 3. 4
Fig. 3. 5

Graphic work No. 9

Plan, section and facade of the building.

Exercise: Perform a complex of images of a building (plan, architectural section and facade) according to individual assignments.

Apply everything on the plan and section required dimensions, both inside and outside the building. Draw the coordination axes and mark them.

Fill in the explication of the premises.

The task is to be performed on the format of drawing paper A2 (594x420) in compliance with all the requirements of GOST, in pencil.

Target: Check theoretical knowledge and practical skills and abilities in reading, implementation and design of architectural and construction drawings.

Instructions for implementation: The assignment contains diagrams of the plan, section, facade of the building and a list of rooms. Start the assignment by building a building plan. To do this, guided by the plan diagram, draw the coordination axes with a dash-dot line.

Show the outer walls 510 mm thick with reference to the coordination axes of 310 and 200 mm and the interior walls with a thickness of 380 mm, with reference to the axes 190 and 190 mm. In the diagram, these walls are drawn with thick lines. The rest of the walls are thin partitions 120 mm thick, they are shown in the diagram with thin lines.

Show window openings in the outer walls, and doorways in the inner walls. Conditional graphic images building elements table.

Walls and partitions that fall into the cutting plane are not hatched, and their contours are outlined with a solid thick line. Building elements located behind the cut plane are shown with a thin line. Window sashes and door canvases are drawn with thin solid lines.

Mark on the plan the position of the cutting plane for the vertical section and make it. Mark heights and dimensions within the contours of the rooms.

Draw the facade of the building.

To complete the assignment, study: the requirements of the SPDS standards (Systems project documentation in construction) GOST 21.101-79, images must meet the requirements of GOST 2.305-68, and also know the theoretical foundations of the section "Architectural and construction drawings".

Many elements of the part have standard sizes... Therefore, when indicating their numerical values ​​in the drawing of the part, the obtained actual dimensions are rounded to the nearest standard, using the normal series of linear dimensions and diameters (GOST 6636-69 *), the standard dimensions of the radii of fillets and chamfers (GOST 10948-64 *), tapers and slopes ( GOST 8593-81), normal angles (GOST 8908-81), turnkey (GOST 642473 *), threads, keyways, grooves for the exit of thread-cutting tools, etc.

On the detailed POC, some elements of the parts are shown in a simplified way, conditionally, or do not show at all, which does not allow identifying their design. Usually this is expressed in the absence of casting and stamping slopes, chamfers, undercut threads when cutting it at the stop, simplified showing of blind holes with threads, grooves and grooves for the exit of threading or grinding tools, etc. without simplifications completely, if it is not specifically stipulated in the standards. Moreover, most of these structural elements in their shapes and sizes are determined by the corresponding GOSTs, which should be used for detailing.

14.4. An example of detailing the general view drawing of the assembly unit "Valve"

To execute the example, a detailed drawing is given - the FOC of the valve (see Fig. 14.1), its specification (Fig. 13.10) and the description of the item being detailed, given below.

A valve is a type of valve designed to regulate the flow of liquid (usually water) in a pipeline and to shut off pipelines.

The liquid is supplied to the valve through the left threaded hole in the housing 1, and the outlet is through the right one. The shut-off device of the valve consists of a valve 4 and a stem 3, connected with the possibility of free rotation of them relative to each other. In the drawing, the valve is shown closed: valve 4 closes the through hole in the body 1 with a diameter of 40 mm, connecting the inlet and outlet. The valve is opened by moving the valve with the stem upward when the latter rotates in the threaded part of the cover 2 using a flywheel 6, fixed on the stem with a screw 8. Raising the stem with the valve higher and lower, change the cross-section of the bore and the fluid flow through the valve.

Details of pos. 6 and 7 not shown

Code 27

Squeeze at

Children position 4

B (2: 1) children pos. 3

All sizes are for reference.

40.02.013.000 ÂÎ

ÌÀÄÈ(ÃÒÓ) ãð. ...

To eliminate leaks between the body and the cover, a gasket 7 is used, and a gland seal consisting of a packing 9 and a threaded bushing 5 is used between the stem and the cover.

Materials of parts pos. 1, 2, 5 - bronze BrOCS3-12-5 ÃÎÑÒ 613-79, details of pos. 3, 4 - brass Ë62 ÃÎÑÒ 15527-70 *, details pos. 6 - Aluminium alloyАË2 ÃÎÑÒ 2685-75, details pos. 7 - Cardboard A GOST 9347-74.

The results of the first stage of reading the POC are as follows:

1. The FOC, made on a scale of 1: 1, shows a valve - a product related to the gate valve of pipelines (see the main inscription of the drawing).

2. According to the specification, the valve consists of seven parts (body, bonnet, stem, valve, bushing, flywheel and gasket), one standard piece (screw) and material (hemp fiber) for packing the stuffing box.

3. Acquaintance with the FOC and the description of the valve made it possible to understand its purpose (in principle, the purpose of any valve is to hold or pass liquid), the general structure and principle of operation.

4. At FOC, in projection communication with each other, three

Valve images: frontal (longitudinal) section (main image), top view and the connection of the halves of the left view and the profile (cross) section. The cuts reveal the internal structure of the entire product and its individual parts. Frontal section, top and left views reflect the external shapes of the valve and most of its component parts. Note that the non-hollow stem 3 is not cut in the sections, and the hole with the thread in it is shown in the local section of the stem.

The shape of the flywheel, in particular the number of spokes and their transverse section explains the view À on the flywheel and the external section of the spoke placed next to it. The shape, location and number of ribs of the valve 4 reveal its appearance Á. The detail  reveals the custom thread shape and dimensions in parts 2 and 3.

In total, the VAL of the valve is represented by seven images.

5. For CHOV 120, 72, 180 ... 200 - overall dimensions; G1 1/2, 60 (size of a wrench for connecting a valve) - installation and connection dimensions; 40 (diameter of the through hole in the valve), 135 ... 155 (distance from the axis of pipelines to the most

remote valve point), 70 (size of the handwheel that controls the valve), G1 1/2, M52x2, and outreach B threads are dimensions that cannot be determined from the drawing. There are no mounting and executive dimensions for the PSC.

The drawing contains inscriptions on the shelves of the leader lines: “3 ribs” - indication of the number of valve ribs 4; “Type 27” - the size of the wrench for tightening the sleeve 5; " Crimp when assembling”- an indication of the connection of valve 4 and stem 3 during assembly; “Grind” - an indication of processing when assembling the adjacent surfaces of valve 4 and body 1.

6. Body 1 is used to accommodate and mount other valve parts in it or on it and connect it to the hydraulic system. The cover 2 provides the translational movement of the rod 3 during its rotation and the placement of the stuffing box in it, which prevents the leakage of liquid between the cover and the rod. The stem moves valve 4 slidingly. The valve closes and opens the body bore connecting the subsea and outlet pipelines. Bushing 5 is a push-and-fit device for the stuffing box seal. Flywheel 6 drives the rod into rotation. Gasket 7 serves to eliminate fluid leaks between the body and the cover. Screw 8 fixes the flywheel to the rod. Gland packing 9 is a gland packing gland.

The fixed detachable connections of the valve are the threaded connection of the body 1 with the cover 2 and the connection of the stem 3 with the flywheel 6 with the screw 8.

The head of the stem 3 is fixed in the bore of the valve 4 by crimping the edges of the bore (one-piece connection). In this case, the stem head is located in the valve bore with a clearance that allows the valve to be centered relative to the valve body bore to be closed and rotate freely relative to the stem.

The rod 3 is screwed into the cover 2 by means of a thread and can, when turned, move in the axial direction relative to it (movable detachable connection). In the fully screwed-in position of the stem, the associated valve abuts against the body and closes the valve.

The bushing 5 is screwed into the threaded hole of the cover 2 and has the ability to turn into it as the stuffing box packing wears out.

into the hole in the cover 2; a gasket 7 is put on the threaded outer part of the lid and the lid is screwed into the housing 1 with a wrench; fill the stuffing box packing (item 9) with the stuffing box of the cover between the latter and the stem; bushing 5 is put on the stem and screwed into the cover, pressing the gland packing; a flywheel 6 is pushed onto the upper part of the stem and attached to the stem with a screw 8.

Recall that the amount of stuffing box packing in the stuffing box should be such that, during assembly, the bushing 5 is wrapped in the cover 2 by 2 - 3 turns, tightly squeezing the stuffing box packing.

When disassembling, unscrew the screw 8 and separate the flywheel 6 from the rod 3; unscrew the bushing 5 from the cover 2 and remove the bushing from the stem; use a wrench to unscrew the cover from the housing 1; turn the stem out of the cover. Valve 4 is not separated from the stem during disassembly.

Having received a general idea of ​​the valve device and the shapes of its constituent parts, at the 2nd stage of reading the FOC, the shapes of all elements of the valve parts are determined in detail and thoroughly. Let us consider the process of such identification of the shapes of parts using the example of a stock.

According to the specification, the stem is assigned position 3, by the number of which the image of the stem is found on the main image of the valve. To do this, find the number 3 above the shelf near this image. The leader line extending from this shelf ends with a dot on the desired image of the stock.

Using the relationship of the images, other stock images are found on the PSC. In total, it has 4 images of the stem: on the main image of the valve, the shapes of all the elements of the stem are basically revealed; the top view and the image on the profile plane of the projections reveal the shapes of the rod elements on which the flywheel is put on; Remote B specifies the shapes and sizes of non-standard threaded rod elements.

The rod material is brass grade L62, from which a rod blank is obtained by injection molding, and then subjected to mechanical processing.

Analysis and comparison of all images of the stock on the ODS, taking into account its purpose and connections with other parts, established at the 1st step of reading the ODS, showed that the stock is an axisymmetric part, all elements of which, with the exception of one,

formed by outer surfaces and located along a common axis in the following sequence:

- a stem head formed by the compartments of the sphere, cylindrical and conical surfaces of rotation and serving to connect the stem to the valve;

- an element with a non-standard external cylindrical thread connecting the stem with the cover and providing a reciprocating movement of the stem;

- cylindrical element connecting rod head and element

threaded;

- a cylindrical element extending from the threaded element, protruding from the cover and allowing the rod to be acted upon from the outside by means of a flywheel;

- a member for fitting onto a flywheel rod formed by four flats formed at the end of the previous cylindrical member;

- a blind hole with a standard metric thread for fixing the flywheel on the stem with a screw, which is the only inner element stock.

Stem mating surfaces are both threaded surfaces, flats and stem heads. Free surfaces of the rod are the surfaces of its cylindrical elements.

A blind hole with a thread in the stem is shown on the FOC in a simplified way without a tapered chamfer at the beginning of the threaded hole and without taking into account the thread stock in the hole and its undercut, which should be taken into account when performing the working drawing of the stem.

Similarly, the shapes of other valve parts were studied and understood.

After completing the reading of the POC (preparatory stage), they proceed to the execution and execution of working drawings of parts in the manner described, as already noted, in section 12.

An analysis of the design, shapes and sizes of parts, carried out when reading the valve's POC, showed that it is advisable to carry out working drawings of the body and lid on A3 formats, and the rest of the parts on A4 formats.

The design of the body, manufactured by casting with subsequent machining of parts of its surfaces, is shown in the working drawing (Fig. 14.2, scale 1: 1), a frontal longitudinal section, the connection of the halves of the top view and the horizontal longitudinal section and the connection of the halves of the left and transverse view

section (Fig.14.2). In educational settings, a horizontal longitudinal section is often not performed, being limited to a top view. The main image of the case is positioned so that the axis of its inlet (inlet) and outlet (outlet) holes is horizontal, and the axis of the hole for the lid is vertical, and the inlet should be on the left, the outlet on the right, and the hole for the lid is directed upwards. This hole in the working drawing shows a chamfer that is not visible on the FOC.

The shape of the cover, also made by casting, is reflected (Fig. 14.3, scale 2: 1) the main image - the connection of the halves of the front view, which shows three faces of the outer prismatic surface, and the front longitudinal section, which shows a through hole with smooth and threaded surfaces, and See also left side view to clarify the prismatic surface shape and turnkey dimensioning. In addition to these two images, for convenience, on the remote elements, the shape of the groove for the exit of the thread-cutting tool and the shape and dimensions of the non-standard thread are specified. Note that the groove is shown in a simplified manner on the FOC, and there are no chamfers in the threaded holes at all. The axis of symmetry in the main image of the cover may be lit

13 18 Á

zonal, as in fig. 14.3, or vertical. In the first case, for the working drawing, the A3 format of the horizontal arrangement is used, and in the second - the vertical arrangement, on

which instead of the left view is given the top view.

The shape of the stock reveals (fig.14.4,

scale 1: 1) its main view from the

cut to display a deaf

threaded holes and top view for

turnkey size setting, additional

for convenience, part of the view

va, on which two flats are visible for

landing of the flywheel, and a remote element

fragment

non-standard

carving. Blind hole with thread on

working drawing is shown without simplified

niy. The main stock image can

be located horizontally (Fig.

since the stock is mainly

formed by coaxial

surfaces

rotation. It is also allowed verti-

location

main view

stem (Fig.14.4), which is due to

more rational

using

drawing fields and wide use

We have machines with vertical processing

surfaces of revolution.

The valve drawing (fig.14.5,

scale 1: 1) two of his

images: top view with local

a sectional view to show the valve bore and a left view to reveal the shape and location of the ribs. In the main view, the valve is in a horizontal position with the ribs directed to the left so that the maximum number of ribs is visible (two for this valve). The valve in the working drawing is shown in the state in which it enters the assembly - before its compression on the stem head.

* Size for reference.

and the dimensions of the groove for the exit of the threading tool, shown in the FOC in a simplified manner. The gasket in the working drawing can be shown with a horizontal position of the axis as a part formed by surfaces of revolution, or with a vertical position of the axis, which it occupies when punching a hole in it in a mold.

 

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