GB2182757A - Sluice, penstock or gate valve - Google Patents

Abstract

A single face sluice, penstock or gate valve comprises a valve body (1) having a through passage (2), with a recess (5) formed in the valve body for accommodating a flat gate (9) which moves up and down to open and close the valve. A seat (4) is formed along the edge of the recess and the gate has a seating projection (10) corresponding to the seat (4). The gate tapers inwardly down its side edges (11, 12) and is rounded at its bottom edge (13). The walls (7) of the recess (5) are formed as seating surfaces dimensioned to receive the side and bottom edges of the gate (9) so that a continuous seal is formed around the through passage (2) when the valve is closed. <IMAGE>

Description

SPECIFICATION Improvements relating to single face sluices, penstocks or face valves This invention relates to single face sluices, penstocks or gate valves for controlling the flow of fluids, hereinafter referred to generically as single face gate valves. By "single face" is meant that the gate valve is designed for fluid flow in only one direction through the gate.

In my British Patent Specification No.

1379675 there is described a gate valve comprising a valve body having a circular through passage, having fluid inlet and outlet ends and having between said ends a branch opening perpendicular to the passage in which a valve member or gate is movable, perpendicularly to the passage, by control gear, to open and close the passage. The gate valve described in said specification is a bi-directional valve, and the branch opening has an elliptical seat for the valve member or gate, which has a corresponding elliptical seat to engage the first mentioned seat when the gate valve is closed.

Moreover, the branch opening for the valve member or gate narrows from the seat to the opposite end of the branch opening, where it merges smoothly with the wall of the fluid passage. The valve member or gate has opposed web-like walls extending beyond the gate proper. These walls taper to correspond dimensionally to the narrowing of the branch opening, and as the valve is closed the weblike walls are guided by the branch opening to fit closely therein in the fully closed position.

The construction described in the aforesaid patent specification has a number of advantages including ease of fitting and operation and the ability to continue to operate reliably under conditions of severe distortion or pressure. However, the construction described is not adapted for use in single face gate valves and the object of the present invention is to provide a single face gate valve in which the above mentioned advantages are realised.

According to the present invention there is provided a single face gate valve comprising a valve body having a through passage, and having a recess perpendicular to the passage, a gate accommodated in said recess and movable perpendicularly to the passage by control gear to open and close the gate, characterized in that said gate has a seating projection at its top edge, tapers inwardly down its side edges and is rounded at its bottom edge, and the walls of the passage are formed as seating surfaces dimensioned to receive said seating projection and said side and bottom edges of the gate so that a continuous seal is formed around the through passage when the valve is fully closed.

The gate is preferably a door-like member, with a flat surface facing upstream.

The seating surfaces on both the valve body and the gate may be unmachined or machined, or fitted with linings of metal, rubber or other suitable material. The valve may in some cases be made of plastic. The valve body may be fitted with part-length or fulllength guides, guide slots and/or guide thrust plates. The sides of the recess also act as a guide thrust face. The recess, the associated seating surfaces in the valve body and the gate may be upstream or downstream with respect to the passage, dependent upon the intended installation of the gate valve.

A few particular examples of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows an exploded isometric view of a first example, adapted for fitting on the upstream side of a retaining wall.

Figure 2 shows a modification of the Fig. 1 example, adapted to be fitted on the downstream side of a retaining wall.

Figure 3 shows one construction of the sealing projection which may be used in the Fig. 1 or Fig. 2 examples.

Figure 4 shows another example of said sealing projection.

Figure 5 shows where anti-friction strips, pads or rollers may be fitted on the downstream side of the gate when pressure is forcing the gate onto the valve body as in the Fig. 1 example.

Figure 6 shows where anti-friction strips, pads or rollers may be fitted on the upstream side of the gate when pressure is forcing the gate away from the valve body.

Referring to the drawing, the gate valve shown in Fig. 1, which is an upright, single face sluice, penstrock or gate valve, consists generally of a valve body 1 having a circular through passage 2, and an upstanding frame 3, for supporting control gear (not shown) to lift and lower the gate. The frame 3 has an upwardly facing sill 4, which forms (as will appear) a seat for part of the gate, the sill having a recess 5 to accommodate the gate.

Beneath the sill 4, a flange is formed in the frame, and the inner surface 7 of this flange forms a further seating surface for the gate, the seating surfaces 4 and 7 forming a continuous sealing face around the passage 2. A portion of the valve body around the circular through passage 2 forms a face 8 of the recess 5 in the sill 4. Foundation boit lugs are provided for securing the valve body to a retaining wall.

The gate itself is denoted by the reference 9 and its top edge has a seating projection 10 (See also Fig. 3). The projection is dimensioned so that its undersurface fits snugly on the sill 4. The gate is otherwise in the form of a flat door-like member. Its side edges 11 and 12 taper inwardly down from the top edge and the bottom edge 13 is rounded. The side and bottom edges of the gate are dimen sioned to fit snugly on the seating surface 7 of the frame 3. When the valve is assembled the gate 9 lies in the recess 5 against the face 8 of the frame. Guides 14 fit to the frame 3 as indicated to guide the gate as it moves up and down, whilst a retaining plate 15, which also fits to the frame 3 retains the gate 9 in position.To open the valve, the gate is moved up into the upper part of the frame 3 and to close the valve the gate is moved down until the seating projection 10 and edges 11, 12 and 13 of the gate seal on sill 4 and the surface 7 of the flange 6. When the valve is closed, a continuous seal is formed around the through passage 2 in the valve body. The seat surfaces may if desired be lined with metal, rubber or other suitable material.

The gate valve shown in Fig. 1 is intended to be fitted so that fluid pressure forces the gate onto the frame 3. In view of this, the surface of the gate 9 facing the frame 3, namely the surface which is not visible in Fig.

1, is or may be fitted with anti-friction strips, pads or rollers at the positions indicated by references 16 and 17 in Fig. 5.

Fig. 2 shows a modification of the Fig. 1 example which is intended to be fitted on the downstream side of a retaining wall, so that fluid pressure forces the gate away from the frame 3. Corresponding parts in the two figures are denoted by the same references. In the Fig. 2 example, the valve body 1 has an enlarged through passage 2 compared with the circular passage of Fig. 1, the passage having cross-sectional dimensions corresponding to the outline of the gate 9. The side guides 14 in Fig. 2 extend downwards of the sill 4 and are recessed to be engaged by a retaining plate or bar 28, fixed to the outer face of the gate 9. This bar slides on the guides 3 when the gate is moved to open or close the valve.

The Fig. 2 example may of course be designed to have a circular through passage 2 as in Fig. 1, and equally the Fig. 1 example may be designed to have the enlarged through passage. In Fig. 6, the references 18 and 19 show positions at which anti-friction strips, pads or rollers are or may be fitted. The face of the gate 9 on which such fitting would occur is in this case that which is visible in Fig. 3.

As shown in Fig. 3, the sill 4 which forms the upper seating surface on the frame 3 may be inclined. In this case, the corresponding seating surface on the projection 10 of the gate 9 is similarly inclined. This constructional feature can be incorporated in either Fig. 1 or Fig. 2 as desired.

Further modification may of course be made in the design of the gate valve.

Claims (9)

1. A single face gate valve comprising a valve body having a through passage, and having a recess perpendicular to the passage, a gate accommodated in said recess and movable perpendicularly to the passage by control gear to open and close the gate, characterized in that said gate has a seating projection at its top edge, tapers inwardly down its side edges and is rounded at its bottom edge, and the walls of the passage are formed as seating surfaces dimensioned to receive said seating projection and said side and bottom edges of the gate so that a continuous seal is formed around the through passage when the valve is fully closed.

2. A single face gate valve according to Claim 1 in which the gate has a flat surface facing upstream.

3. A single face gate valve according to Claims 1 or 2 in which the gate is flat on both surfaces and anti-friction means are provided against the downstream surface.

4. A single face gate valve according to any preceding claim, in which a seat is provided on the frame along the recess and said gate seating projection is arranged to sit on said seat when the valve is closed.

5. A single face gate valve according to Claim 4, in which said seat is inclined and said seating projection is similarly inclined.

6. A single face gate valve according to Claim 4 in which said seat is provided along three sides of said recess.

7. A single face gate valve according to any preceding claim in which said recess has a face perpendicular to said through passage, and said gate is positioned against said face.

8. A single face gate valve according to any preceding claim in which said gate is held in position in said recess by means of upright guides fitted to the frame which permit said gate to move up and down to open and close the valve.

9. A single face gate valve substantially as any of the examples herein described with reference to the accompanying drawings.