JPH0557531U - valve - Google Patents

Abstract

(57) [Abstract] [Purpose] The seat surface 20 ′ of the valve body 20 that comes into contact with and separates from the valve seat 11 in the valve box 10 is prevented from being damaged by foreign matter, and
Heat resistance said surface, wear resistance, creep resistance, and resistance to radioactive, and at -40～300 ° C., to obtain a applicable valve 60 kg / cm ² of liquid or gas, the vapor of 20 kg / cm ^2. [Constitution] Polyether ether ketone (PEEK)
The PEEK annular sheet 2 is applied by the fixed disk 25 which is pressed against the valve body 20 with screws 28 against the annular sheet 21.
1 is fixed to the valve body 20.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 This invention is applied to various types of valves used in petrochemical plants, such as sluice valves, globe valves, swing-type and lift-type check valves, safety valves, etc. The present invention relates to an improvement of a valve body that opens and closes.

[0002]

[Prior Art]

 The original purpose of the valve is to always keep the secondary pressure (low pressure side) at zero leakage with respect to the primary pressure (high pressure side) when the valve is closed by the valve body. The valves used in petrochemical plants that are generally sold in the market are made of metal for the valve body and seat of the valve box. If the surface of the seat is normal, when the valve is closed, there will be no leakage of secondary pressure. Can be in the state of.

[0003]

[Problems to be solved by the device]

 However, as the usage time elapses and the valve is repeatedly opened and closed several times during plant operation, foreign matter such as small metal pieces mixed in the fluid adheres to the surface of the valve body and the seat of the valve box. If the valve is closed in this state, the surface of the sheet will be peeled off due to the foreign matter being caught, and the sheet will be scratched and the secondary side pressure will leak. When this happens, disassemble the valve, apply grinding powder to the surface of the damaged seat of the valve body and valve box, and slowly slide it down until the damage disappears, so that the seat surfaces are in close contact with each other. As described above, it is necessary to correct it with a file, etc., or slide it together to make it possible to restore the secondary pressure so that there is no leakage, and it takes a very long time to maintain this valve. And requires a high degree of skill. For this reason, some valve bodies have a Teflon resin sheet attached to the surface that contacts the valve seat of the valve box. If leakage occurs in the secondary pressure, disassemble the valve and replace the Teflon resin sheet with a new one. Although it can be made to have zero leakage by replacing it with a new one, the heat resistance, durability, and wear resistance of Teflon resin are relatively weak, and the maximum operating temperature is about 200 ° C. For safety, it can be used only for fluids at room temperature to 100 ° C, and the surface of the sheet is easily deformed.

[0004]

[Means for Solving the Problems]

 The present invention was developed in order to solve the above-mentioned problems, and a valve having a valve body that opens and closes the flow of fluid in the valve box by contacting and separating from the valve seat in the valve box is provided. The polyether ether ketone (PEEK) annular sheet with a stepped inner circumference consisting of a large diameter opening and a small diameter opening is applied to the surface that comes in contact with and separates from the valve seat of the PEEK annular seat. It is characterized in that a fixed disk is fitted and the fixed disk is screwed to the valve body to fix the PE EK annular seat to the valve body.

[0005]

【Example】

 In each of the illustrated embodiments, 10 is a valve box, 11 is a valve seat in the valve box, 12 is a fluid inlet to the valve box, 13 is a fluid outlet from the valve box, 20 is a valve element, and 21 is a valve. It is a polyether ether ketone (PEEK) annular sheet fixed to the surface of the valve body 20 that contacts the valve seat 11. The PEEK annular sheet 21 has a thickness of about 10 mm, and its inner circumference 22 is stepped by a large diameter opening 23 and a small diameter opening 24. Reference numeral 25 denotes a fixed disk for fixing the PE EK annular seat 21 to the valve body, and a small diameter portion 26 fitted to the inner circumference of the small diameter opening 24 and a small fitting to the inner circumference of the large diameter opening 24, Further, it has a large diameter portion or a collar 27 that comes into contact with the peripheral portion of the bottom of the large diameter opening 24, and the small diameter portion 26 is fitted into the small diameter opening 24 of the PEEK annular seat 21 and is tightened to the valve body 20 with a screw 28. The bottom of the large-diameter opening 23 is pressed against the valve seat contact surface of the valve body by 27 to fix the PEEK annular seat 21 to the valve body. The material of the valve box 10, the valve body 20, and the fixed disk 25 is S 25C.

FIG. 1 shows a sluice valve (gate valve), a valve box 10 having valve seats 11 and 11 facing each other in a V shape, and an inlet 12 for fluid to the valve box and an outlet 13 at both ends of the valve box. either will do. A wedge-shaped valve body 20 corresponding to the above-mentioned valve seats 11 and 11 is fixed to the lower end of a valve rod 31 that is vertically moved by female and male screw engagements by turning the handle 30. The wedge of this valve body 20 is fixed. A circular recess 32 having a depth of 7.5 mm, which is slightly shallower than the thickness (10 mm) of the PEEK annular sheet 21, is provided on both of the shaped slopes 20 ′, and the PEEK sheet 21 is fitted into the circular depression 32, and is formed on the inner periphery thereof. The fixed disk 25 is fastened to the bottom of the circular recess 32 with a plurality of screws 28 at equal intervals in the circumferential direction to fix the PEEK annular sheet. The outer diameter of the PEEK annular sheet 21 is, for example, 116 mm, while the inner diameter of the circular recess 32 is, for example, 115.95 ± 0.02 mm. Press into. As a result, the PEEK annular seat 21 projects outwardly from both wedge-shaped slopes 20 ', 20' of the valve body 20, and when the valve body 20 is fully lowered and closed, the valve seats 11, 11 of the valve body 10 are closed. Close contact with and block the flow of fluid. When the valve is closed and the PEEK annular seat 21 is in close contact with the valve seats 11 and 11 of the valve box, foreign matter adheres to the surface of the seat, and even if it is bitten into it, the PEEK annular sheet 21 remains in the seat. Wraps around and does not get scratched. Furthermore, it has excellent heat resistance, abrasion resistance, creep resistance, and radiation resistance, the operating temperature is -40 to 300 ° C, and the applicable fluid is water (seawater, miscellaneous water, pure water, pressure 60 kg / cm).² ), Steam (pressure 20 kg / cm² ), Various gases and chemicals (pressure is 60 kg / cm for each) ² ). In the case of the sluice valve, since the valve body has a wedge shape, the PEEK annular seat can be deformed and tightened until the secondary side pressure becomes zero, and the valve is highly airtight. Furthermore, since PEEK annular seats are fitted and fixed on both sides 20 ', 20' of the valve body, even if the surface of one of the seats becomes defective, the other seat will not leak secondary pressure. The metal sheet of the valve box will not be scratched and the reliability of the valve will be improved. In addition, maintenance is short and requires no high-level maintenance technology because all that is required is to disassemble and clean the valve and replace the PEEK annular seat 21 with a new one.

FIG. 4 shows a globe valve in which the valve box 10 is horizontal and has a conical (conical) valve seat 11. The valve body has a cylindrical shape with a bottom, and an annular recess 33 is formed on the bottom surface of the bottom. The PEE K annular sheet 21 is fitted in and fixed by the fixed disk 25. In this case, the screw 28 is a bolt that integrally protrudes downward from the center of the lower surface of the valve body, and a nut 34 with a detent is screwed onto this. In the case of a normal globe valve body in which the valve seat of the valve box is a horizontal ring, a circular recess 32 similar to the above-mentioned sluice valve is provided on the lower surface of the cylindrical bottom, and the PEEK annular seat is provided there. Then, the PEEK annular seat may be fixed by press-fitting and fixing the fixed disk fitted on the inner circumference to the valve body with a plurality of screws.

Above, two typical examples of the valve of the present invention are illustrated. The PEEK annular seat is fixed to the valve body of a known swing check valve or safety valve with a plurality of screws in the same manner as the sluice valve. However, in the case of a lift check valve, fix it with a nut with a detent screwed to the central bolt as in the globe valve.

A small gap 29 is maintained between the bottom surface of the circular recess 32 or the annular recess 33 to which the PEEK annular sheet 21 is to be fixed and the end surface of the small diameter portion 26 of the fixed disk 25 facing the circular recess 32. Due to the gap, the seat 21 is slightly distorted and brought into close contact with the valve body to improve airtightness, prevent back leakage, and strongly tighten the screw. Even if the tightening is a little loose for some reason, it loosens. Is absorbed and the seat 21 is stably fixed to the valve body. In order to prevent the screws 28 from loosening, it is advisable to form punched recesses 35 at several locations in the circumferential direction between the outer periphery of the dish-shaped head and the edge of the countersunk hole of the fixed disk.

[0010]

[Effect of the device]

As is clear from the above, according to the present invention, even if foreign matter adheres to the seat surface, it deforms and wraps so that it does not get scratched, and it has excellent heat resistance, wear resistance, creep resistance, and radiation resistance. -40～300 ° C. in 60 kg / cm ² of liquid or gas, it is possible to obtain the applicable valve steam 20 kg / cm ^2.

[Brief description of drawings]

FIG. 1 is a sectional view of a sluice valve.

FIG. 2 is an enlarged sectional view of the valve body of FIG.

FIG. 3 is a side view of the valve body of FIG.

FIG. 4 is a sectional view of a globe valve.

5 is an enlarged cross-sectional view of the valve body of FIG.

[Explanation of symbols]

 10 valve box 11 valve seat 20 valve body 21 PEEK annular seat 22 inner circumference 23 large diameter mouth 24 small diameter mouth 25 fixed disc 26 small diameter portion 27 large diameter portion or collar 28 screw

Claims (1)

[Scope of utility model registration request] 1. A valve provided with a valve body that comes into contact with and separates from a valve seat in a valve box and opens and closes a fluid flow in the valve box, wherein a surface of the valve body that comes into contact with and separates from the valve seat has a large-diameter opening. Polyether ether ketone (PEEK) with stepped inner circumference consisting of small diameter mouth
A valve characterized in that an annular seat is applied, a fixed disc is fitted on the stepped inner periphery of the PEEK annular seat, and the fixed disc is fixed to the valve disc with a screw to fix the PEEK annular seat to the valve disc.