Reinforcement attachment methods. Ways of connecting fittings to the pipeline Types of valves

Electric drives are produced with the highest torques from 0.5 to 850 kgf-m in normal and explosion-proof versions with different explosion protection categories. These and other parameters of electric drives are reflected in the symbol of the drive, which consists of nine characters (numbers and letters). The first two characters (numbers 87) designate an electric drive with an electric motor and a gearbox. The next sign is the letter M, A, B, C, D or D, indicating the type of connection of the actuator to the valve. Type M connection is shown in fig. II.2, types A and B - in fig. II.3, types C and D in - fig. II.4, type D - in fig. P.5. The dimensions of the connecting elements are given in table. 11.106.

11.106. Dimensions of connecting elements of unified electric actuators of valves

All actuators are attached to the valve with four studs. Stud diameters and bearing pad dimensions for various types connections are different. With an increase in the torque developed by the drive, they increase. Types C, D and D connections are provided with two keys in order to unload the studs from shearing forces created by the torque transmitted from the actuator to the valve.

The next figure conditionally indicates the torque of the electric drive. In total, seven gradations are provided for the total range of torques from 0.5 to 850 kgf-m (Table 11.107). Within the prescribed interval, the adjustment to the required torque is made by adjusting the torque limiting clutch.

11.107. Symbols of parameters of electric drives

The next figure conventionally denotes the speed (in rpm) of the drive shaft of the electric drive, which transmits rotation to the valve stem nut or spindle. Eight frequencies of rotation of the drive shaft of the electric drive are provided - from 10 to 50 rpm (Table 11.107).

Then, conditionally, the total number of revolutions of the drive shaft is indicated, which it can make, depending on the version of the box of limit and torque switches. In total, six gradations are provided (Table 11.107).

This limits the first group of characters. The second group consists of two letters and a number. The first letter of the second group of designations indicates the version of the drive according to climatic conditions: Y - for a temperate climate; M - frost-resistant; T - tropical; P - for elevated temperature. The second letter indicates the type of connection of the control cable to the electric drive box; Ш - plug connector; C - gland entry. The last digit indicates the explosion protection version of the actuator. The number 1 indicates the normal version H; the remaining numbers from 2 to 5 indicate the explosion protection categories: 2 - VZG category; 3 - category B4A; 4 - category V4D; 5 - category РВ. Thus, the electric drive under the designation 87V571 US1 has the following data: 87 - electric drive; B - type of connection; 5 - torques from 25 to 100 kgf-m; 7 - frequency of rotation of the drive shaft 48 rpm; 1 - total number of revolutions of the drive shaft (1 - 6); U - for a temperate climate; C - gland entry of the control cable; 1 - explosion protection standard N.

Below are brief specifications and dimensional data of electric drives of the unified series.

Electric actuators of normal execution with type M connection with a two-way torque limiting clutch (Fig. A.6). Symbols 87M111 USh1 and 87M113 USh1. Designed to control pipeline valves in structures with a maximum torque of up to 2.5 kgf-m. Torque control limits from 0.5 to 2.5 kgf-m. The total number of revolutions of the drive shaft 1 - 6 (87M111 USh1) and 2 - 24 (87M113 USh1). Drive shaft speed 10 rpm. The drive is equipped with an AV-042-4 electric motor with a power of 0.03 kW and a rotation speed of 1500 rpm. The gear ratio from the handwheel lever to the drive shaft = 1. A force of up to 36 kgf can be applied to the flywheel rim. Electric drives have a built-in box! travel and torque switches. The mass of the electric drive is 11 kg. The overall dimensions of electric drives 87M111 USh1 and 87M113 USh1 are shown in fig. P.6.

11. 108. Symbols of electric drives

11.109. Brief technical characteristics and mass of electric drives

11.110. Symbols of electric drives

Electric actuators of normal execution with type A connection with a two-way torque limiting clutch (Fig. II.7). The maximum torques created by the drives are 6 and 10 * kgf-m. Eight modifications of electrical appliances are provided (Table 11.108). Specifications and mass of electric drives are given in Table. 11.109. Rotational speed of the electric motor shaft 1500 rpm Gear ratio from the flywheel of the manual override to the drive shaft i = 3. The electric drives have a built-in box of position and torque switches. The overall dimensions of the electric drives are shown in fig. P.7.

Electric drives of normal execution with type B connection with a two-way torque limiting clutch (Fig. II.8). The maximum torque on the drive shaft is 25 kgf-m (regulation interval from 10 to 25 kgf-m). There are twelve modifications of electric drives (Table 11.110). Technical characteristics of electric drives are given in table. 11.111. The frequency of rotation of the motor shaft is 1500 rpm. The overall dimensions of the electric drives are shown in fig. II.8. The mass of the electric drive is 35.5 kg.

11.111. Brief technical characteristics of electric drives

Electric actuators of standard execution with type B connection with a two-way torque limiting clutch (Fig. II.9). The highest torque on the shaft is 100 kgf m (regulation interval from 25 to 100 kpm). There are twelve modifications of electric drives (Table 11.112). Technical characteristics and mass of electric drives are given in Table. II. 113. The frequency of waxing the motor shaft is 1500 rpm. The overall dimensions of the electrical wires are shown in fig. II.9.

Electric actuators of standard design with G-type connection with a two-way torque limiting clutch (Fig. 11.10). The highest torque on the shaft is 250 kgf-m (regulation interval from 100 to 250 kgf). There are twelve modifications of electric drives (Table 11.114). Technical characteristics and mass of electric drives are given in Table. 11.115. The frequency of rotation of the motor shaft is 1500 rpm. The overall dimensions of the electric drives are shown in fig. UFO.

11.112. Symbols of electric drives

11.113. Brief technical characteristics and mass of electric drives

11.114. Symbols of electric drives

11.115. Brief technical characteristics and mass of electric drives

Electric actuators of standard design with type D connection with a two-way torque limiting clutch (Fig. 11.11). The highest torque on the drive shaft is 850 kgf-m (regulation interval from 250 to 850 kgf-m). Drive shaft speed 10 rpm. There are six modifications of electric drives (Table 11.116). The gear ratio from the flywheel to the drive shaft i = 56. Permissible force on the rim of the flywheel handwheel 90 kgf. The electric drives are equipped with an AOC2-42-4 electric motor with a power of 7.5 kW and a shaft speed of 1500 rpm. The mass of the electric drive is 332 kg. The overall dimensions of the electric drives are shown in fig. 11.11.

Rice. 11.12. Wiring diagram control of electric drives of the unified series:

D - asynchronous electric motor with a squirrel-cage rotor; KVO, KVZ - travel microswitches MP 1101 opening and closing; KV1, KV2 - additional travel microswitches MP 1101; VMO, VMZ - moment microswitches MP 1101 opening and closing; O, 3 - magnetic starters for opening and closing; LO, LZ, LM - signal lamps "Open", "Closed" and "Clutch"; KO, KZ, KS - control buttons "Open", "Closed" and "Stop"; 7 - potentiometer PPZ-20, 20 kOhm; Pr - fuse; A - automatic; 1 - 4 - contacts of microswitches

Explosion-proof electric drives are also provided:

11.116. Symbols of electric drives

The electrical control circuit of electric drives (the same for all) is shown in fig. Item 12. In the “Open” position, the LO signal lamp is on, in the “Closed” position, the LZ and LM lamps are on, in the “Emergency mode” position, the LM lamp is on. The operation of the microswitches is clear from the table. 11.117.

11.117. Operation of microswitches (Fig. 11.12)

2018-01-16T15:39:03+03:00

One of the main issues when choosing pipeline fittings is the type of its connection to the system. Usually, the already existing piping system dictates to us which type of connection to choose. But if you are faced with the task of designing such a system, then it is important to know all the possible types of connection of pipeline fittings to the system in order to choose the ideal option for your conditions. From our article you will learn about all types, their pros and cons, you will better navigate the types of connections. We'll start with the most popular.

flange connection

This is a connection using two metal plates adjacent to each other. The plates have holes through which bolts or studs pass and are tightened with nuts from the other side, thus pressing the flanges against each other. For greater reliability and tightness of the connection, protrusions, grooves, etc. are made on the plates, and gaskets are installed between the metal plates. Most often, the plates are rounded, but this is not necessary. Occasionally you can find square flanges, rectangular or with three corners, but their production is more expensive. Such forms of flanges are used only when absolutely necessary, for example, if space restrictions require it. It is used on industrial pipelines with a diameter of 50 mm or more.

The word "flange" came from the German flansch, meaning the same as in Russian - a flat metal plate with holes.

Flange connection is one of the most popular connections in pipeline fittings. For the manufacture of flanges, cast iron is most often used - gray or malleable, as well as steel of various grades. Gray cast iron is the most cost-effective solution, but ductile iron tends to withstand a greater range of pressures and temperatures. An even more expensive and durable solution is cast steel flanges. But at the same time, steel is more susceptible to plastic deformation than brittle, but perfectly shaped cast iron.

Video: Installing an LD Flanged Ball Valve on a Pipe Using

Advantages of flange connection of pipeline fittings

• Strong, reliable connection.
• Withstands high pressure.
• High tightness. But it depends on the seals used.
• Can be mounted and dismantled multiple times.

disadvantages

• Large overall dimensions of the flange connection. Big mass.
• High consumption of metal and labor intensity of production, and hence the price.
• The bolts pressing the flanges together must be periodically tightened to ensure proper tightness. This is especially important in systems where the pipe is subject to vibrations (decided by installation before the flange connection) or temperature changes.

Threaded, socket connection

Also one of the most popular types of connections, but for pipeline systems of small diameter (usually up to DN 50) and low pressures (up to 1.6 MPa). It is very often found in household pipe fittings, for example for. Its essence is simple: the pipe has a thread and the armature has a thread, the latter is screwed onto the first.

The pipe can be threaded using special tools if it is not available and the equipment has not been installed before. Threaded pipe fittings at one end are made in the form of a hexagon for gripping with an adjustable wrench and screwing the fittings onto the pipe thread.

Video: how to thread a metal pipe and install a threaded ball valve

There are various options performance threaded connections: internal or external thread. The fittings can have an internal thread on one side and an external thread on the other, or the same type on both sides. And there are also various thread standards, such as ISO 228/1 or DIN 2999. You need to take this into account when choosing.

The word "coupling" comes from the Dutch word mouw, meaning "sleeve".

To ensure the tightness of threaded types of connections, they use additional seals - special FUM tapes, flax thread, as well as especially thick lubricants on top of them. All this is applied to the external thread.

Union connection

This is a subspecies of a threaded connection, which is used on valves of tiny sizes - up to DN 5. When connected, a fitting with a thread is pulled to the thread on the pipe with a union nut. It is used for narrow-purpose pipes, such as laboratory pipes. It is also used for implanting various measuring devices into pipelines.

Advantages of threaded connections of pipe fittings

• Low price.
• Does not require additional parts for installation, such as flanged type.
• Easy to install, even easier to replace.

disadvantages

• Not suitable for high pressures.
• The larger the diameter, the more effort must be applied to screw the reinforcement onto the thread with the seal.

Weld connection

If the ends of the pipe fittings look just like pipes without any additions, then they are joined to the system by welding. This is the most reliable and hermetic connection, properly performed which, you can get the absolute structural conformity of materials. Having welded a valve or valve to a pipe, you do not have to tighten the bolts, as with a flange connection, moreover, the cost and weight of such fittings will be much less.

This type of connection can often be found on pipeline systems transporting liquids and gases hazardous to health, where the slightest leaks cannot be allowed and absolute tightness is required. Welded joints are characterized by the saying “set it and forget it”. The main thing is to qualitatively connect the pipe with the fittings so that the welding place is not weaker than the pipe wall.

The ends of the pipes must be prepared before welding, and each metal is prepared in its own way. We offer you a video with the most in a simple way welding.

Advantages of a welded joint

• Absolute tightness when the welding procedure is carried out correctly.
• Low cost rebar.
• Light weight.
• Small size, the connection does not take up much space in space.

disadvantages

• Qualified personnel are needed, which increases the final cost of installing such fittings.
• A laborious dismantling process, such gate valves or taps need to be installed once and for all.

Clamp quick-release connection (Tri-Clamp)

A modern quick-release fitting for pipeline fittings, mainly used in the food industry, pharmacology and other industries where sterility and cleanliness are important. After all, this type of connection allows you to regularly remove and clean, disinfect the equipment installed with this mount.

The clamp connection consists of two fittings, a seal and a clamp. The clamp presses the two fittings to the seal and to each other, resulting in a tight connection. What is such a clip, we invite you to study the video.

The connections of fittings to the pipeline (Fig. 13.2) are detachable (flanged, coupling, pin) and one-piece (welded and soldered). The most common flange connection. Advantages flange connection fittings - the possibility of multiple installation and dismantling on the pipeline, good sealing of joints and the convenience of tightening them, high strength and applicability for a very wide range of pressures and passages. The disadvantages of a flange connection are the possibility of loosening and loss of tightness over time (especially under vibration conditions), increased laboriousness of assembly and disassembly, large overall dimensions and weight. These disadvantages of flanges are especially affected by pipelines of large diameters, designed for medium and high pressures.

When assembling such a connection, dozens of large-diameter studs are tightened with a special tool. Tightening these flange connections often requires a team of locksmiths. With an increase in the nominal pressure and the flow area of ​​the flanges, the mass of both the valve itself and the entire pipeline (taking into account the counter flanges) increases and the metal consumption increases. In connection with the indicated disadvantages of flanged joints, as well as an increase in the diameters of pipelines and their working pressures, valves with butt welds are becoming more common. Such fittings, in particular, equip the main gas and oil pipelines.

The advantages of joining fittings to a pipeline by welding are great, which is, first of all, complete and reliable tightness of the connection, which is especially important for pipelines transporting explosive, toxic and radioactive substances. In addition, the welded joint does not require any maintenance and tightening, which is very important for main pipelines, where a minimum of maintenance is desirable. A welded joint saves metal and reduces the weight of fittings and pipelines. Especially effective is the use of fittings with ends for welding on such pipelines, where the pipeline itself is assembled entirely by welding.

The disadvantage of welded joints is the increased complexity of dismantling and replacing fittings, since for this it has to be cut out of the pipeline.

For small fittings, especially cast iron, the coupling connection is most often used. In this case, the ends of the reinforcement have the form of couplings with an internal thread. Since flanges for small reinforcement have a relatively large mass (often of the same order as the mass of reinforcement without flanges), the use of flanges in such conditions leads to an unjustified increase in metal consumption. In addition, tightening bolts for small diameter flanged joints is more labor intensive than tightening a box joint and requires the use of special torque wrenches.

Rice. 13.2. The main types of connection of fittings to the pipeline:

a - flanged (cast flanges with a connecting ledge and a flat gasket); b - flanged (steel welded flanges end-to-end with a protrusion-cavity seal with a flat gasket); in- flanged (cast flanges with a spike-groove seal with a flat gasket); g - flanged (steel flat welded flanges with a flat gasket); d - flanged (cast steel flanges with a lens gasket); e- flanged (cast steel flanges with oval section gasket); w - coupling; h - tsapkovoe.

A coupling connection is usually used in cast fittings, because it is easiest to obtain an external coupling configuration (turnkey hexagon) by casting. In this regard, the main area of ​​application of coupling joints is fittings for low and medium pressures. For small high-pressure fittings, which are usually made from forgings or rolled products, the pin connection with external thread under the cap nut.

Flange connections of pipelines and fittings, designed for a nominal pressure of 1-200 kgf / cm 2, are standardized. At the same time, the types of flanges (GOST 1233-67), their connecting dimensions (GOST 1234-67), designs, performance dimensions and technical requirements are standardized. In special, technically justified cases (with shock or increased load, short service life, specific properties of the environment - toxicity, explosiveness, chemical aggressiveness, etc.), the standard allows the manufacture of flanges according to industry standards or drawings deviating from GOST, but with the obligatory implementation of connecting sizes according to GOST 1234-67.

Flanges are usually round. The only exceptions are cast-iron flanges, tightened with four bolts, designed for pressure p y not higher than 40 kgf / cm 2. They are allowed to be square.

Standard valve flanges are divided into several types according to the design of the gasket connection. The simplest of them - with a smooth front surface (with or without a connecting protrusion), unprotected type, without a groove for a gasket. These flanges are the easiest for mounting and dismantling fittings and for replacing gaskets, however, the tightness of the connection they create is the least reliable.

Flanges designed for high pressures (from 40 to 200 kgf / cm 2) are used with toothed steel gaskets, for low ones - with soft or soft-core gaskets. To protect soft gaskets from being knocked out by the pressure of the working medium in fittings, flanges with a cavity for the gasket are used. In this case, the counter flanges are made with a ledge, so that the flanges outside the gasket form a lock protecting it. Such flanges are used with soft gaskets or metal ones with a soft core. The third type of valve flanges, designed for the same gaskets as the previous one, are flanges with a gasket groove. Reciprocal flanges have a spike. Thus, the gasket is protected by a flange lock both from the outside and from the inside, which increases the reliability of the connection. However, installation, dismantling of fittings and replacement of gaskets are somewhat difficult here compared to flanges of the first type.

For high pressures, starting from p y \u003d 64 kgf / cm 2, seals of two more standard types are used in flanges - for a lens gasket and for an oval gasket. These seals are more economical and reliable in high pressures than conventional flat gaskets. In such flanged connections, the gaskets touch the sealing surfaces of the flanges theoretically along a line, but practically along a very narrow ring. This allows for equal overall dimensions flanges and tightening forces create high specific pressures on the seal. Thus, it becomes possible to use massive steel gaskets of high strength and durability in place of conventional soft ones.

FEDERAL AGENCY FOR TECHNICAL REGULATION AND METROLOGY

NATIONAL

STANDARD

RUSSIAN

FEDERATION

Pipe fittings ROTARY ACTUATORS Mounting dimensions

Industrial valves - Multi-turn valve actuator attachments

Industrial valves - Part-turn valve actuator attachments

Official edition

Standartinform

Foreword

1 DEVELOPED by Closed Joint Stock Company “Scientific and Production Company “Central Design Bureau of Valve Engineering” (CJSC “NPF “TsKBA”) on the basis of ST TsKBA 062-2009 “Pipeline fittings. Rotary drives. Connecting dimensions»

2 8NESEN Technical committee for standardization TC 259 "Pipe fittings and bellows"

3 APPROVED AND 8PUT INTO EFFECT by the Order of the Federal Agency for Technical Regulation and Metrology of August 20, 2013 No. 529-st.

4 This standard takes into account the main regulatory provisions of the following international standards:

ISO 5210 Pipe fittings. Connecting dimensions of multi-turn actuators "(ISO 5210 Industrial valves - Multi-turn valve actuator attachments", NEQ):

ISO 5211, “Pipe fittings. Mounting dimensions of part-turn actuators" (ISO 5211 "Industrial valves - Part-turn valve actuator attachments", NEQ)

5 INTRODUCED FOR THE FIRST TIME

The rules for the application of this standard are established by GOST R 1.0 - 2012 (section 8). Information about changes to this standard is published in the annual (as of January 1 of the current year) information index "National Standards", and the official text of the changes and amendments is published in the monthly information index "National Standards". In case of revision (replacement) or cancellation of this standard, a corresponding notice will be published in the next issue of the monthly information index "National Standards". Relevant information, notification and texts are also posted in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet (gost.ru).

© Standartinform. 2014

This standard cannot be fully or partially reproduced, replicated and distributed as an official publication without the permission of the Federal Agency for Technical Regulation and Metrology

1 ... 1 ... 1 ..2 16

1 area of ​​use............................................... .........................................

3 Terms and definitions .......................................................... ................................................

4 Connection types............................................................... .........................................

5 Designation of connection types............................................................... ...................

Annex A (mandatory) Mounting dimensions of multi-turn

drives for types of connections MCH. MK. AC. AK. B. W. D. D ..........................

Bibliography

NATIONAL STANDARD OF THE RUSSIAN FEDERATION

Pipe fittings

ROTARY DRIVES

Mounting dimensions

pipeline valves. Drives of rotary action The connecting dimensions

Introduction date -2014-02-01

1 area of ​​use

This standard applies to rotary actuators and actuators (hereinafter referred to as actuators) (multi-turn and semi-rotary, electric, pneumatic, hydraulic, as well as gearboxes) and establishes the types of actuator connections to pipeline valves, the connecting dimensions of the actuators and the dimensions of the mating connections of the pipeline valves controlled by them .

2 Normative references

This standard uses normative references to the following standards:

GOST R 52720-2007 Pipe fittings. Terms and Definitions

GOST 22042-76 Studs for parts with smooth holes. Accuracy class B. Design and dimensions

3 Terms and definitions

For the purposes of this standard, the following terms are used with their respective

definitions:

3.3 multi-turn actuator May have the ability to withstand axial load (1).

3.4 part-turn actuator: A device that transmits torque when its output element is rotated one revolution or less, not having the ability to withstand an axial load.

3.5 gearbox