JPH0473371B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an elastic material used in fluid pipes such as water supply (including water supply, sewerage, industrial water supply, agricultural water supply, etc.), oil pipeline, etc. The present invention relates to a method of lining a valve body of a valve body valve seat gate valve.

[Prior Art] Material combinations of the valve body valve seat and the valve body valve seat in normal gate valves include metals and metals, metals and elastic materials, and elastic materials and elastic materials. Of these,
An elastic body valve seat gate valve (also referred to as a soft seal gate valve) refers to a combination other than a metal-to-metal combination, and is standardized as seen in, for example, JWWA B120-1984.

In this elastic body valve seat gate valve, a method for manufacturing a valve body in which the entire inner circumferential surface and outer circumferential surface of the shaft hole and side hole of the valve body body are lined with an elastic material is disclosed in Japanese Patent Publication No. 58-49388. (hereinafter referred to as "prior art")
) has already been proposed.

In this method, first, a core (this is called a "temporary core") of the desired shape is placed in the shaft hole and side hole of the valve body.
is inserted to form a predetermined lining gap, and the gap is filled with lining rubber to form an unvulcanized inner lining.

Next, the temporary core is removed from the valve body in this state and replaced with another core (this will be referred to as the "real core"), and the valve body is placed in a required mold with a predetermined lining gap. The inner and outer linings are completed by supporting the inner and outer linings in a fully vulcanized state and filling them with outer rubber in a fully vulcanized state.

However, in this conventional technology, it is necessary to accurately install the temporary core and the real core in the mold, and it is also necessary to perform lining processing on the inner rubber and outer rubber in two steps. The disadvantage is that it takes time and effort.

[Technical Problem of the Present Invention] The present invention solves these problems and provides an elastic body valve seat gate valve that is extremely simple, accurate, low cost, and has a good appearance on all external and internal surfaces of the valve body. The purpose of the present invention is to provide a method for lining a valve body (technical problem).

[Configuration and operation of the present invention] In order to achieve the above object, the method of lining the valve body of an elastic body valve seat gate valve of the present invention adopts the following configuration (technical means). That is, in a method in which a valve body of an elastic body valve seat gate valve is inserted into a mold and the entire external and internal surfaces of the valve body are lined with an elastic material, the outer surface of the valve body and the mold are Between the inner surface and the inner surface, support materials shaped so that they will not come out after lining are placed at multiple locations to avoid the water stop part of the valve body and to support the valve body vertically and horizontally within the mold. It is characterized in that an outer lining space is secured by interposing the outer lining space, and then an elastic material in a fluid state is filled in the outer lining space.

Here, the "supporting material shaped so that it does not slip out after lining" is specified in the following examples. Furthermore, although the supporting material is usually fixed to the valve body using an adhesive, it is not a requirement that the supporting material be fixed.

Furthermore, in the present invention, appropriate means such as injection molding, compression molding, etc. are used as a method for forming the lining.

With this configuration, the lining process on the outer surface of the valve body can be done all at once.

[Effects of the present invention] Since the valve body lining processing method of the present invention has the above configuration, it has the following unique effects.

According to the method of the present invention, since the supporting material is installed in a shape that will not fall out after lining before lining processing, the supporting material will not slip out or come off, and there will be no possibility of adhesive etc. protruding or poor appearance. There is no

According to the method of the present invention, since the support material is installed in the vertical and horizontal directions, it is easy to position the lining when the valve body is inserted into the mold, and it is possible to easily position the lining when the valve body is inserted into the mold. Lining defects due to lateral slippage can be prevented.

[Mode of implementation] The present invention adopts the following embodiments.

The surface of the supporting material that contacts the valve body must be larger than the surface that contacts the mold.

According to this aspect, since the supporting material portion remaining on the surface of the elastic body coating after lining processing becomes small, an extremely good valve body of the elastic body valve seat gate valve that does not appear to have any supporting material at first glance can be manufactured. can.

Forming the side surface of the support material into an uneven shape.

According to this aspect, extraction is prevented by engagement between the uneven side surface and the lining layer, and the contact support surface with the mold or the core is not reduced. Therefore, it is effective for the inner lining of the valve body with respect to the strong and brittle core.

[Example] Hereinafter, an example of the present invention will be described based on the drawings.

1 and 2 show an embodiment of an elastic valve seat gate valve manufactured by the lining processing method of the present invention.

The gate valve V consists of a valve body body 1 which is subjected to lining processing, a lining layer 2, and a support material 3.

The valve body 1 is manufactured by metal casting, has a predetermined outer shape, and has a shaft hole 11 penetrating inside from the upper end to the lower end, and a shaft hole 11 that communicates orthogonally with the shaft hole 11 and opens to both sides. A side hole 12 is provided, and a narrowed portion 13 is provided at the lower end of the shaft hole 11.

The lining layer 2 is applied to the outer surface and inner surface (shaft hole 11, side hole 12) of the valve body 1, and on the outer surface,
Its lower end edge 21 is formed in an arc shape, its both side edges 22 are formed as guide parts, and its front and rear wall surfaces 23 are formed in a bulged shape.

In the inner lining layer, a screw top K is installed at the intersection 14 of the shaft hole 11 and the side hole 12,
The main gate valve V is moved up and down by the rotation of the spindle shaft L that is screwed into the screw top K. In addition, in the outer lining layer, the lower end edge 21 and the front and rear wall surfaces 23 form a "compression water stop part" that comes into compressive contact with the valve seats I and J of the valve box H and blocks the flow of fluid. (See Figure 5).

The support material 3 is embedded in the lining layer 2 on the outer and inner surfaces of the valve body 1 and has a shape that does not easily come out.

The supporting member 3 has one surface that contacts the valve body 1 fixed through an adhesive. 3A is a vertical support member, and 3B is a horizontal support member.

Various aspects of the support material 3 are shown in FIGS. 3 and 4.

In the one shown in FIG. 3, the surface that comes into contact with the valve body 1 is larger than the other surface. For example, FIG. 3a shows a cross-sectional view of a truncated cone or obelisk shaped support, and FIG. 3b shows a cross-sectional view of a right circular or square pyramidal support.

The support member 3 shown in FIG. 4 has an uneven side surface.

The supporting material 3 is made of materials such as non-corrosive metals (eg, stainless steel, titanium), rubber and plastics with a hardness of 90Hs or more, and ceramics.

FIG. 5 shows how the gate valve V is used. H is a valve box, and I and J are valve seats of the valve box H. Further, K is a screw top, and L is a spindle shaft.

Next, an embodiment of the method of the present invention for manufacturing the gate valve V will be described.

When the outer lining is carried out by the method of the present invention, the valve body body 1 formed in a predetermined shape is prepared in advance, and the support material 3 is
is fixed to the surface of the valve body 1 with adhesive, avoiding the water stop portion.

Next, a two-part mold (upper mold, lower mold divided into upper and lower molds) formed into a predetermined internal shape (i.e., a shape for determining the outer lining layer and supporting the core described later) is used. Prepare,
The valve body 1 with the supporting material attached thereto is placed in the lower mold.

At the same time, there is a shaft hole 1 inside the valve body 1.
A shaft hole core and a side hole 12 which are inserted into the shaft hole 1 in a penetrating manner.
Attach the core for the side hole inserted into the hole. That is, both ends of the shaft hole core are connected to the shaft hole 1 of the valve body 1.
One end of the side hole core protrudes from the side hole 12 of the valve body 1 and engages with the mold, and the other end protrudes from the side hole 12 of the valve body 1 and engages with the mold. It comes into contact with the side of the core.

When installing the cores, the lower side hole core and the shaft hole core are installed on the valve body 1 and engaged with the engaging portion of the lower mold, and then the upper mold and engage the end of the upper side hole core with the engaging part of the upper mold.

By the above procedure, a space for outer lining is created between the outer surface of the valve body 1 and the inner surface of the mold.
Further, a space for the inner lining is secured between the hole of the valve body 1 and the core.

Thereafter, the elastic lining material in a fluid state is press-fitted through an injection path leading to the mold. When using rubber for the lining material, the temperature should be 155~
185℃, pressure 150~300kgf/ ^cm2 , 15~60
Perform main vulcanization in minutes.

Rubber and plastic having a hardness of 90Hs or less are used as the elastic material.

In the above-mentioned embodiment method, the so-called injection molding of fluidized rubber has been described. Similarly, the fluidized rubber is filled in a coating form on the surface of the valve body 1 in a mold, and then the upper and lower parts are molded. This does not prevent the use of a so-called press molding mode in which the part mold is compressed and molded.

Furthermore, when a non-corrosive metal such as stainless steel or titanium is used for the support material 3, it is convenient because the pinhole inspection of the manufactured gate valve V can be carried out through the metal.

When the outer lining and inner lining are carried out by the method of the present invention, the supporting material 3 is fixed to the outer surface of the valve body 1 and to the inner surfaces of the shaft hole 11 and the side hole 12.

One shaft hole core and two side hole cores are inserted into the shaft hole 11 and the side hole 12. At this time, the shaft hole core is inserted into the shaft hole 11 in a penetrating manner,
The side hole core is inserted into the side hole 12 while sandwiching the shaft hole core.

Next, the valve body 1 with the core attached thereto is inserted into the lower mold of the two-part mold, and the upper mold is covered, thereby completing the lining preparation work.

In this state, there is a method in which a fluidized elastic lining material is press-fitted from the injection path leading to the mold to carry out lining processing in the same manner as in step I above.

According to this method, the core can be easily positioned, and the outer and inner surfaces of the valve body can be lined all at once, improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a partially cross-sectional, partially side view of an embodiment of an elastic body valve seat gate valve according to the method of the present invention, FIG. 2 is a partially cross-sectional, partially front view thereof, and FIGS. 3 and 4 are views according to the present invention. 5 is a cross-sectional view showing various aspects of the support material used in the present invention, and FIG. 5 is a diagram showing how the present elastic body valve seat gate valve is used. 1... Valve body body, 2... Lining layer, 3...
Support material, V...Elastic body valve seat gate valve.

Claims (1)

[Scope of Claims] 1. A method of inserting a valve body of an elastic body valve seat gate valve into a mold and lining the entire external and internal surfaces of the valve body with an elastic material, comprising: Between the outer surface and the inner surface of the mold, a supporting material with a shape that does not come out after lining is placed to avoid the water stop part of the valve body and to support the valve body within the mold in the vertical and horizontal directions. An elastic body valve seat gate valve characterized in that the outer lining space is secured by interposing the outer lining space at a plurality of locations, and then the outer lining space is filled with an elastic material in a fluid state. A method of lining the valve body. 2. The method of lining a valve body of an elastic body valve seat gate valve according to claim 1, wherein the support material has a surface in contact with the valve body that is larger than a surface in contact with the mold. 3. A method of lining a valve body of an elastic body valve seat gate valve according to claim 1, wherein the side surface of the support member is formed in an uneven shape.