JPH0716143Y2 - Butterfly valve - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a butterfly valve in which a commercially available steel pipe (normal steel pipe) is used as a valve case.

[Conventional technology]

There are various on-off valves used for water piping, etc.
The flow path is blocked by a disk-shaped valve body,
A so-called butterfly valve that opens a flow path by rotating is well known. The body of this butterfly valve was conventionally made of a cast product. That is, the main body case excluding the disk valve body, the valve rod, the seal member, and the like was an integrally cast product that was cast into the required shape.

[Problems to be solved by the invention]

In a conventional butterfly valve that uses a body case made of a cast product, this is different from the rubber seat ring that seals between the disc body and the body body when the disc-shaped valve body is in the flow path blocking position. It was not possible to weld the retainer used to secure the in place into the body by welding. Therefore, it is necessary for the main body to have a complicated inner surface shape so that the rubber seat ring can be fitted into a predetermined position in the main body, and the seat retainer itself is also precisely machined from a round bar or a plate-like object by machining. It needs to be processed, and it was usually fixed with bolts when mounting it.

For this reason, there is a problem that the productivity of the valve component is poor, the assembly is complicated, the cost is high as a whole, and the weight is heavy.

[Means for solving problems]

The present invention, which was made to solve the above problems,
A valve case made of a commercially available steel pipe cut to a required length, a bonnet portion mounted orthogonally to the outside of the valve case, a valve rod mounted in the bonnet portion so as to be rotatable about an axis, and the valve. A disc-shaped valve body concentrically arranged in the case and fixed to the valve rod, and between the outer circumference of the valve body and the inner circumference of the steel pipe when the valve body is in the position of blocking the flow passage. A butterfly valve consisting of a rubber seat ring for sealing and a ring-shaped seat retainer for fixing the rubber seat ring to the inner surface of a steel pipe. The seat retainer is a thin section of a metal thin-walled pipe with a small diameter part and a large diameter part. A butterfly formed by forming a stepped ring having a diameter portion, pressing the edge of the rubber seat ring against the inner peripheral surface of the steel pipe with the outer peripheral surface of the small diameter portion, and welding the large diameter portion to the inner surface of the steel pipe. Provide a valve too It is.

At that time, a plurality of notch tongues protruding outward are provided on the large diameter portion of the seat retainer so that the tongues and the inner surface of the steel pipe are spot-welded, and the rubber seat ring Several grooves in the circumferential direction are provided on the edge of the outer peripheral surface.

[Action]

In the butterfly valve of the present invention, the valve case of the main body cuts a commercially available steel pipe to a predetermined length and uses it as a straight pipe, so that the inner surface is a true cylinder. Therefore, if a disc-shaped valve element with a perfect circle is used, the seal when the valve is seated (flow passage cut-off position) is
A rubber sheet ring with a simple shape having the same thickness over the entire circumference can be sufficiently achieved. The seat ring can be held by a seat retainer consisting of a simple circular ring. The seat retainer may be a thin-walled pipe cut into slices. At this time, by molding this ring-slicing pipe into a stepped ring having a small diameter part and a large diameter part, the rubber seat ring can be pressed uniformly over the entire circumference in the small diameter part, and the large diameter part can be used as a valve. It can be fixed by spot welding with the inner surface of the steel pipe of the case.
In this way, the seat portion of the valve body can be attached by welding, and the butterfly valve can be manufactured with a simple fixing means that replaces the fixing means such as mechanical fitting and screwing.
The material may be one that is available on the market, and a lightweight and inexpensive butterfly valve can be provided.

〔Example〕

FIG. 1 shows an embodiment of the butterfly valve of the present invention. Reference numeral 1 is a valve case in which a commercially available steel pipe is cut to a required length, and expanded diameter portions for connection are provided at both ends thereof. At the center of the valve case 1, the valve case 1
The bonnet part 2 is attached orthogonally to. This bonnet part 2 also consists of a normal pipe. In the illustrated example, the pipe end of the bonnet portion 2 is fixed to the outer periphery of the valve case 1 by welding. The valve case 1 corresponding to the axis of the bonnet portion 2 has a hole through which the valve rod 3 is inserted. The valve rod 3 inserted into the bonnet portion 2 penetrates this hole and projects into the case 1. A disc-shaped (disc-shaped) valve body 4 is fixed to the end portion thereof. At that time, a perfect circular valve body 4
Is arranged so that the center of the is substantially aligned with the central axis of the steel pipe of the valve case 1. On the other hand, a cylindrical bottom case 12 is also attached to the outside of the case 1 on the side facing the bonnet part 2, and a lower valve rod 13 is attached to the bottom case 12 so as to be rotatable around its axis through the pipe wall of the case. The lower part of the valve body 4 is supported by the lower valve rod 13. A bearing 14 is installed in the bottom case 12. On the other hand, a bearing 15 is inserted inside the bonnet portion 2 near the case 1, and a seal member 16 is attached near the upper end by an O-ring. At the position shown in the figure, the valve body 4 is at an angle (the position where the disc surface is orthogonal to the axis of the case 1) that blocks the flow path of the case 1, and by rotating the valve rod 3 by 90 °, Open the flow channel by changing the angle to the position shown. When the valve body 4 is in the position of blocking the flow path (the position shown in the figure), it is necessary to completely seal the outer peripheral edge of the valve body 4 and the inner peripheral surface of the case 1. For this purpose, a rubber sheet ring 5 is used, and a ring-shaped seat retainer 6 for fixing the rubber sheet ring 5 to the inner surface of the case 1 is used.

2 to 4 show the details of the rubber seat ring 5, which is a rubber ring belt having holes 16 and 17 for passing the valve rod 3 and the lower valve rod 13 as shown. , Its outer peripheral surface has a surface that is in close contact with the inner peripheral surface of the case 1, and as shown in Fig. 3, the inner peripheral surface has a cross-sectional shape with slightly thin edges and a slightly raised central portion ( As shown in FIG. 3), when viewed from the outer peripheral surface, it is molded so as to have a concave curved surface so that the diameter becomes slightly larger from the center toward both end edges as a whole. When a molded product having such a shape is mounted as shown in FIG. 1, both thin portions of the edge are pressed by the sheet retainer 6 and a reaction force when the central portion is compressed acts, so that a seal is produced. The effect will increase. As shown in the enlarged view of FIG. 5, a plurality of grooves 10 along the circumferential direction are engraved on the outer peripheral surfaces of the thin portions, and when the thin portions are pressed by a sheet retainer, When the groove is crushed, the seal with the inner surface of the case 1 becomes complete. This groove 10 is shown in FIGS. 5 (a), (b),
As shown in (c) and (d), it is preferable that the cross section has a square shape, a hemispherical shape, a triangular shape, a ladder shape, or the like.

6 to 8 show the details of the seat retainer. The seat retainer actually presses both side edges of the rubber seat ring 5 as shown by 6a and 6b in FIG. 1, but both can have the same shape.
In the present invention, the sheet retainer 6 is made of a commercially available thin metal pipe. That is, the thin-walled pipe is cut into a ring with a predetermined short width, and a large-diameter portion 8 is formed by expanding the approximately half width by press forming. This makes it possible to easily obtain a stepped ring having a small diameter portion 7 and a large diameter portion 8. Both side edges of the rubber sheet ring 5 are pressed by the small diameter portion 9 of the step ring. The large diameter portion 8 is brought into contact with the inner surface of the steel pipe of the valve case 1, and spot welding is performed here and there to fix it to the inner surface of the steel pipe. In spot welding, as shown in FIG. 8, a plurality of notch tongues 9 projecting outward are provided at several places of the large-diameter portion 8,
If the tongue piece 9 and the inner surface of the steel pipe are spot-welded, the tongue piece 9 is in complete contact with the inner surface of the steel pipe, so that good welding can be performed.

In order to prevent deterioration of corrosion resistance to fluid due to local material change due to spot welding and crevice corrosion around the spot welding area, electroless multi-layer nickel plating is applied to the front surface of the inner circumference of the body to completely mask them. It's good to do.

〔effect〕

The butterfly valve of the present invention having the above-described structure can be manufactured at a significantly lower cost and with higher productivity than the conventional cast valve, and is also lightweight. If the same steel pipe as the pipe to which this valve is applied is manufactured, a part of the piping material will become a valve, and it will be possible to have a valve function at the required location after the pipe construction. Further, since the rubber seat ring and the seat retainer for fixing the same are simple in shape, and the welding means can be applied for the fixing, the tightness and durability of the seal are improved and the valve assembling work is simplified and the material Since most of them are commercially available pipes (standard products), the dimensional accuracy is good.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the butterfly valve of the present invention,
2 is a front view of the rubber seat ring, and FIG. 3 is a front view of FIG.
III-III line sectional view, FIG. 4 is a perspective view of a rubber seat ring, FIG. 5 is a partially enlarged view of FIG. 3, FIG. 6 is a front view of a seat retainer, and FIG. 7 is FIG. FIG. 8 is a sectional view taken along the line VII-VII of FIG. 8, and FIG. 8 is a perspective view of the seat retainer. 1 …… Valve case, 2 …… Bonnet, 3 …… Valve rod, 4 ……
Disc-shaped valve body, 5 …… Rubber seat ring, 6 …… Seat retainer, 7 …… Small diameter part of seat retainer, 8 …… Large diameter part of seat retainer, 9 …… Notched tongue, 10 …… Groove .

Claims (3)

[Scope of utility model registration request] 1. A valve case 1 made of a commercially available steel pipe cut to a required length, a bonnet portion 2 mounted orthogonally to the outside of the valve case 1, and rotatable inside the bonnet portion 2 about an axis. To the valve stem 3, a disc-shaped valve body 4 concentrically arranged in the valve case 1 and fixed to the valve stem 3, and a position at which the valve body 4 blocks the flow path. A butterfly valve including a rubber seat ring 5 for sealing between the outer circumference of the valve body 4 and the inner circumference of the steel pipe at a certain time, and a ring-shaped seat retainer 6 for fixing the rubber seat ring 5 to the inner surface of the steel pipe. The seat retainer 6 is formed by molding a thin section of a metal thin pipe into a stepped ring having a small diameter portion 7 and a large diameter portion 8. The outer peripheral surface of the small diameter portion 7 forms the rubber sheet ring. Pressing the edge of No. 5 against the inner peripheral surface of the steel pipe, Butterfly valve comprising 8 to welding the inner surface of the steel pipe. 2. The large-diameter portion 8 of the seat retainer 6 has a plurality of notch tongues 9 protruding outward, and the tongues 9 and the inner surface of the steel pipe are spot-welded. Butterfly valve. 3. The rubber sheet ring 5 has a plurality of circumferential grooves 10 at the edge of its outer peripheral surface.
Butterfly valve described in.