RU2297610C2 - Method of sealing branch pipes and bench for testing valving systems - Google Patents

Abstract

FIELD: testing engineering.

SUBSTANCE: method comprises using the pressure of testing fluid for sealing branch pipes of valving system when it is mounted in the testing setup and using hydraulic system with testing fluid for sealing the article to be tested and testing bench. The testing bench has two plugs for branch pipes of the article to be tested that provide pressure-tightness due to the pressure of the testing fluid.

EFFECT: enhanced reliability.

3 cl, 2 dwg

Description

The invention relates to testing equipment for pipe fittings / TPA /, in particular ball valves, wafer version.

A device for sealing hollow products when tested for tightness by AS SU 1422041 A1, publ. 09/07/1998, in which the sealing of nozzles of a flangeless design by using a hydraulic cylinder with an elastically deformable sealing element is provided. The deformation of the annular sealing element is ensured by its compression between the protrusion of the hollow rod and the sleeve, which is moved by the piston of the hydraulic cylinder, into which pressure is supplied from a separate hydraulic system.

The known method contains the following operations:

- coaxial alignment and input into the nozzle of the protrusion of the rod of the hydraulic cylinder with a sealing ring;

- supplying excess pressure to the cavity of the hydraulic cylinder to ensure elastic deformation of the sealing ring and maintaining this pressure for the entire duration of the test;

- supply to the cavity of the test product / for example, pipe fittings / test fluid under excess pressure;

- control of the parameters of the test product / for example, resistance to the effects of the test fluid or leaks /;

- removing excess pressure and draining the test medium from the cavity of the test product;

- pressure reduction in the cavity of the hydraulic cylinder to atmospheric.

A significant disadvantage of this method of sealing flangeless nozzles in the need for a separate hydraulic system to create pressure in the hydraulic cylinder, which ensures the deformation of the annular sealing element. In relation to a TPA having two coaxially placed nozzles, each nozzle will need a hydraulic cylinder to ensure their coaxial alignment without distortions with the nozzles of the tested TPA. With the diameters of the conditional test TPA up to 800 mm, this operation is difficult to implement.

The technical result of the invention is to simplify the method and bench for testing pipe fittings of a flangeless design by using the test pressure created in the cavity of the tested injection molding machine to seal the nozzles.

To achieve a technical result in the method, the end face of the second TPA nozzle is pressed to the sealing ring of the second plug, the TPA with plugs is installed through the spacers in the stand, the ends of the nozzles are pressed to the plugs through the sealing rings with a normalized force sufficient to fill the TPA inner cavity with test fluid without leaks, then fill the inner cavity of the injection molding machine with test liquid and apply test pressure there, while compressing and defo the formation of the sealing rings of the plugs and thereby eliminating the gap between the inner wall of the test TPA and the sealing rings of the plugs. In the test bench, each plug contains a housing with a cylindrical recess, in which a piston with elastically deformable rings is placed, one of which is placed in the annular recess of the plug housing and is designed to press the end of the pipe of the test product, the second is located between the end surfaces of the housing and the piston of the plug to seal the gap between the plugs in the inner surface of the pipe, and the third and fourth are placed between the piston and the cylindrical undercut of the housing and serve to limit deformation of the second ring of the plug, and the housing of each plug is equipped with a fitting and valves for supplying and draining the test fluid through the piston into the cavity of the test product, in addition, one of the plugs is additionally equipped with a fitting and channels for draining air through the piston from the cavity of the tested product into the atmosphere and back.

In addition, a tee is inserted into the device and connected to a fitting for supplying and draining the test fluid of one of the plugs, a source of test fluid is connected to the first input of the tee, and a source of test pressure is connected to the second input of the tee through the valve.

The structure of the test bench for TPA wafer version shown in figure 1. Figure 2 shows a section of one of the plugs for sealing nozzles TPA wafer version.

The stand of figure 1 contains a fixed 1 and a movable 2 faceplates with connecting rings 3 and 4, which include the protrusions of the spacer elements 5 and 6, fixed to the faceplates 1 and 2 with brackets 7 and 8, respectively. The recesses 9 and 10 of the elements 5 and 6 include the protrusions 11 and 12 of the plugs 13 and 14, respectively. The plugs 13 and 14 are connected by elements 15 and 16 to the nozzles 17 and 18 of the test TPA and are pressed to the end of the nozzles 17 and 18 through the elastic sealing rings 19 and 20 with the normalized force from the faceplate 2. The plug 13 is equipped with a tee 21 for supplying and dumping the test fluid through the nozzle 22 and creating a test pressure in the cavity of the test TPA through the pipe 23. In addition, in the upper part of the plug 13 there is a valve with a fitting 24 for air drainage when filling the internal cavity of the test TPA. The right plug 14 is equipped with a valve with a fitting 25 for supplying the test pressure through the nozzle 26 to the right side of the test TPA, for example, when the ball valve plug is closed.

The test process consists of the following operations:

- fix the plugs 13 and 14 to the nozzles 17 and 18 of the test TPA using elements 15 and 16;

- install TPA with plugs in the stand through spacers 5 and 6;

- tighten the normalized force from the faceplate 2 to the ends of the nozzles 17 and 18 to the plugs 13 and 14 through the sealing rings 19 and 20;

- fill the internal cavity of the test TPA test through the pipe 22; after which the valve 24 and the pipe 22 are closed;

- submit the test pressure through the nozzles 23 and 26 into the cavity of the TPA and conduct the test at various positions of the working body of the TPA / for example, ball plugs /.

As the pressure in the cavity of the product increases, the pistons 27 and 28 deform the sealing rings 29 and 30, respectively, which ensures reliable sealing of the cavity of the tested TPA with the pressure of the test fluid without using a separate hydraulic system for sealing and without significant compression forces of the body of the tested product.

In figure 2. shows a section of the left stub 13 of the stand. The piston 27 can move in the housing 31 of the plug under the pressure of the test fluid, while it deforms the elastic rings 32 and 33 and the sealing ring 29. The test pressure is supplied through the fitting 34 through channels 35, 36, 37, channels 38, 39, 40 and the fitting 41 are necessary for the drainage of air from the cavity of the product during its filling with test fluid. The rings 32 and 33 limit the deformation of the sealing ring 29 within the elasticity of the material.

To drain the test fluid from the cavity of the test TPA, the nozzles 23 and 26 are closed, then the drain in the nozzles 22 is opened, and then the valve 24 is opened for air to enter the cavity of the product.

New in the proposed method of sealing the nozzles is the use of pressure of the test fluid for self-sealing of the internal cavity of the tested TPA. As a result, both the sealing process and the test bench for injection molding machines are greatly simplified. In this case, a large compression force of the body of the tested TPA is excluded.

Claims (3)

1. A method of sealing pipes of pipe fittings of a flangeless design, comprising preloading one end of the pipe of the pipe fittings to the sealing ring of the plug and sealing the gap between them, filling the internal cavity of the pipe with test fluid, characterized in that the end of the second pipe of the pipe fitting is pressed to the sealing ring of the second plug , install the pipe with plugs through the spacer elements into the stand, press the ends of the pipes to the plugs through the seals rings with normalized force sufficient to fill the inner cavity of the nozzles with test fluid without leakage, after which they fill the inner cavity of the nozzles with test fluid and apply test pressure there, compressing and deforming the sealing rings of the plugs and thereby eliminating the gap between the inner wall of the test nozzle pipe fittings and o-rings plugs. 2. A test bench for wafer-type pipe fittings, comprising a fixed and movable faceplate with spacers, a power drive of the fixed faceplate, a source of test pressure, two plugs for the ball valve nozzles, characterized in that each plug contains a housing with a cylindrical recess in which the piston is located with elastically deformable rings, one of which is located in the annular recess of the plug housing and is designed to compress the pipe under test to the end of the pipe reinforcement, the second is placed between the end surfaces of the housing and the piston of the plug and is designed to seal the gap between the plugs in the inner surface of the nozzle, and the third and fourth are located between the piston and the cylindrical groove of the housing and serve to limit the deformation of the second ring of the plug, and the housing of each plug is equipped with a fitting and channels for supplying and draining the test fluid through the piston into the cavity of the test product, in addition, one of the plugs is additionally equipped with a fitting and channels for drainage of air through the piston from the cavity of the test product into the atmosphere and back. 3. The test bench according to claim 2, characterized in that a tee is inserted into the device and connected to a fitting for supplying and draining the test fluid of one of the plugs, the source of the test fluid is connected to the first input of the tee, and connected to the second input of the tee through the valve source of test pressure.

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