JPS5849388B2 - Valve rubber lining method for soft seal valves - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for rubber lining a valve body of a soft seal valve.

Recently, there has been a tendency for soft seal valves to be used more frequently.
It is difficult and problematic to apply rubber lining to the inner peripheral surface of the shaft hole and side hole formed in the valve body, and to the outer peripheral surface of the valve body.When lining the outer surface, it is necessary to support the valve body within the mold using support pins. Since a gap is formed in the die, the support pin portion becomes a hole when die-cutting, which not only needs to be filled, but also has the disadvantage that this portion is easily damaged during use later.

The present invention was made to solve the above-mentioned problems, and the shaft hole of a valve body having a shaft hole and a side hole communicating with the hole is provided with a shaft metal fitting, and the side hole is provided with a blind piece as the inner surface of the hole. A lining gap is inserted between the two, and this gap is communicated with an extruder, and unvulcanized rubber heated to a temperature of 70 to 80°C is filled into the gap by the extruder, and the filling is completed. After that, remove the valve body from the extruder, remove the shaft fitting and blind piece, insert the core and blind piece for main vulcanization in their place, insert the valve body into the mold, and press from both ends of the valve body. The protruding ends of the core are supported in the mold to maintain a gap between the core and the mold surface for the outer lining, and rubber from a rubber pot is filled into this gap with a thickness of 155 to 18 mm.
This relates to a method for lining a valve body rubber lining for a soft seal valve, which is characterized by press-fitting and vulcanizing at a temperature of around 5°C, and also completing vulcanization of the rubber in the shaft hole and side tag.

An example of implementing the present invention will be described below with reference to the drawings.

The valve body 1 is made of metal and has a predetermined external shape, and has a shaft hole 2 penetrating to the upper and lower ends, and a side hole 3 that communicates orthogonally with the hole and opens to both sides.
A narrowed part 2a is provided at the lower end of the shaft hole 2, and after unvulcanized rubber is brought into close contact with the inner peripheral surfaces of the shaft hole 2, the narrowed part 2a, and the side hole 3 in the inner lining process described later, the valve body is Rubber is adhered to the outer surface in the outer surface lining process described later to complete vulcanization.

(1) Inner lining process First, the shaft hole 2 of the valve body 1 has a shaft fitting 4, and the side hole 3 has a blind piece 5.
Insert.

The shaft fitting 4 has a round bar shape, and has a small end 4a projecting from the narrow perforation 2a at its lower end, and has an upper end projecting from the upper end of the shaft hole 2.

The blind piece 5 includes a main body portion inserted into the side hole 3 and a protrusion portion 5a that contacts and closes the outer periphery of the side hole 3.

The dimensions of the shaft fitting 4 and the blind piece 5 are those of the shaft hole 2 and the side hole 3.
A predetermined lining gap is formed between the inner surface of the lining and the inner surface of the lining.

In order to inject rubber into this lining gap, it is connected to an extruder 6.

The extruder 6 has a built-in screw and a constriction mouthpiece 7 at the extrusion port.
are fixed with the flanges 6a, 7a, bolts 8a, and nuts 8b, and the injection port 9 is fixed to the end of the narrowed mouth 7 with the bolt 1.
0, and an inverted bowl-shaped support 11 that supports and protects the top of the shaft fitting 4 is fixed inside the inlet fitting 9 by a plurality of arms 12, and below the support 11 a centering pin 13 is fixed from the outside. Set up towards.

Further, the lower part of the injection port fitting 9 is formed into a narrowed part 9a having a diameter slightly larger than that of the shaft fitting 4, and the upper end part 1a of the valve body 1 is fitted into the lower end of the narrowed part 9a, and a flange 9b is provided on the outer periphery of the lower end. Further, a flange 9c is provided on the outer periphery above the narrowed part 9a, and a fixture 14 is attached and detached below the flange 9c by means of the flange 14a, a bottle 15, and a nut 16, and a blind piece 5 is provided at the bottom of the fixture 14. an inward flange 14 that engages with the protrusion 5a;
b is provided and the protruding portion 5a of the blind piece is tightened with a bolt 17.

To perform the inner lining, as shown in FIG. 1, insert the upper part of the shaft fitting 4 into the narrowed part 9a from the lower end of the injection port fitting 9, fit the upper end of the shaft fitting 4 to the support 11, and center it. The center is determined by pin 13.

Then, the valve body 1 is inserted from the lower end of the shaft fitting 4 through the shaft hole 2, and the valve body upper end 1a is fitted to the lower end of the inlet fitting 9. It is made to protrude from the narrowed portion 2a.

Next, the blind piece 5 is fitted into the side hole 3, and the fixture 14 surrounding it is fixed from below to the flange 9c with the flange 14a1 bolts 15 and nuts 16, and the lower end flange 14
The bolts 17 of b are tightened to fix the valve body 1, the shaft fitting 4, and the blind piece 5.

In this way, a predetermined lining gap is formed between the inner surfaces of the shaft hole 2 and side hole 3 of the valve body 1 and the shaft fitting 4 and the blind piece 5, and the narrowed part 9a of the shaft fitting 4 and the injection port fitting 9 is formed. Since there is formed an injection gap communicating with the lining gap, the unvulcanized rubber extruded by the extruder 6 can be injected into the lining gap.

This unvulcanized rubber is injected at a temperature of 70 to 80°C and an extrusion pressure of 5 to 6 ky/1.

The injection amount is limited until the injected rubber flows out from the gap between the narrowed portion 2a at the lower end of the shaft hole of the valve body 1 and the small diameter portion 4a at the lower end of the shaft fitting.

After the injection is completed, the valve body 1 is removed from the extruder 6 and an outer surface lining process is performed.

(2) Outer surface lining step The shaft fitting 4 and blind piece 5 are removed from the valve body 1, which has the unvulcanized lining rubber R1 bonded to the shaft hole 2 and side hole 3 in the inner surface lining step. As shown, the core 18 and blind piece 19 for main vulcanization are inserted and brought into close contact with the circular rubber R1, and both ends 18a, 18b of the core 18 are made to protrude so as to engage inside the mold 20.

The mold 20 is hollowed out from the lower mold M1 and the upper mold M2, and both molds M1, M
2 is provided with mold surfaces M3 and M4 to form a cavity corresponding to the desired external shape of the valve body, and engaging portions Ma and Mb with both ends 18a and 18b of the core 18 are provided at both ends thereof. The valve body 1 is suspended in the cavity of the mold by the engaged core 18 with a required gap from the mold surface, and the rubber bot 21 on the mold 20 is inserted into the gap through the injection path 22. Inject outer rubber R2.

The temperature is around 155-185°C, the pressure is 80kg/C
rIL, and main vulcanization is performed in 15 to 60 minutes, and at the same time, the lining rubber R1 on the inner peripheral surface also completes main vulcanization.

The product taken out from the mold 20 after completion of vulcanization is shown in Figures 5 and 6.
The result is as shown in the figure.

Both the inner rubber R and the outer rubber R2 are fully vulcanized and covered with the same rubber lining (2) on the inside and outside.

As described above, the lining rubber R1 and the outer lining rubber R2 are produced in separate processes, and the lining rubber R1 is left unvulcanized, the outer lining rubber R2 is injected at the vulcanization temperature, and the lining rubber R1 is also heated. Vulcanization is completed at the same time, which simplifies the process compared to performing the main vulcanization in separate processes for the inside and outside, and when injecting the outer rubber, the valve body is engaged with both ends of the core protruding from both ends in the mold. Since it is supported in a suspended manner within the mold cavity by engagement with the valve body, there is no need to insert a support pin between the outer surface of the valve body and the mold surface of the mold. The support pin is not embedded in the injected rubber, and not only does it not require the extra process of removing the support pin from the outer rubber after mold release and filling the hole with rubber, but the part is easily damaged later. There are no such problems, so it is a software with excellent performance.
There is an advantage that the seal valve can be provided at low cost.

[Brief explanation of drawings]

The drawings show an example of the implementation of the present invention, and Fig. 1 is a longitudinal sectional front view of the state in which the lining rubber is injected, and Figs. 2 and 3 are cross sections taken along the 4 is a longitudinal sectional front view of a state in which the outer rubber is injected, FIG. 5 is a front view of the product, and FIG. 6 is a side view of the product. 1 is a valve body, 2 is a shaft hole, 3 is a side hole, 4 is a shaft fitting, 5 is a blind piece, 6 is an extruder, 18 is a core for main vulcanization, 19 is a blind piece, and 20 is a mold , 211 is a rubber tube, 22 is an injection path,
R1 is inner rubber, R2 is outer rubber, and R is rubber lining.

Claims (1)

[Claims] 1. Insert a shaft fitting into the shaft hole of a valve body having a shaft hole and a side hole communicating with the hole, and insert a blind piece into the side hole with a gap for lining between the inner surface of the hole, and fill this gap. is connected to an extruder, and unvulcanized rubber heated to a temperature of 7 to 80°C is filled in the same gap by the extruder. After this filling is completed, the valve body is removed from the extruder, and the shaft fitting and blind piece are Remove the core and insert a blind piece for main vulcanization in their place, insert the valve body into the mold, and support it in the mold by both ends of the core protruding from both ends of the valve body. A gap for the outer lining is maintained between the mold surface and the rubber pot.
A method for lining a valve body rubber lining for a soft seal valve, characterized by press-fitting and vulcanizing at a temperature between 5 and 185 degrees Celsius, and also completing vulcanization of the rubber in the shaft hole and side holes.