Relating to gate valves
View Patent ↗A gate valve ( 10 ) is provided and comprises: a valve body ( 12,14 ) including an aperture ( 20, 22 ); a gate ( 42 ) reciprocally movable within the body between a first position in which the aperture is occluded to a second position in which the aperture is open; a bearing member ( 36 a, 36 b ) over which the gate moves in the body; and a loading member ( 30 a, 30 b ) for urging the bearing member against the gate. The loading member comprises a lattice-like elastomeric mat ( 30 a, 30 b ).
1. A gate valve comprising:
a valve body including an aperture,
a gate reciprocally movable within the body between a first position in which the aperture is occluded and a second position in which the aperture is open,
a bearing member in contact with a major surface of the gate and over which the gate moves in the body, and
a loading member arranged to urge the bearing member against the major surface of the gate, in which the loading member comprises a lattice-like elastomeric mat, the mat comprising a framework which defines a plurality of cut-outs, and the framework has a cross section with chamfered sides.
2. A gate valve as claimed in claim 1 , in which the mat is configured to be separated from and to be placed against the bearing member.
3. A gate valve as claimed in claim 1 , in which the mat has a generally honeycomb-like configuration.
4. A gate valve as claimed in claim 1 , in which the mat is formed from a material having a Shore hardness in the range A5 to A25.
5. A gate valve as claimed in claim 1 , in which the valve body comprises two complimentary housing sections, and in which each section comprises an aperture-defining part which is separate from and carried on or by a main body part.
6. A gate valve as claimed in claim 5 , in which the aperture-defining part and the main body part are formed from the same material.
7. A gate valve as claimed in claim 5 , in which the aperture-defining part and the main body part are formed from different materials.
8. A gate valve as claimed in claim 1 , in which a respective bearing member is provided on each side of said gate, and a respective loading member is provided for each bearing member to urge them against the gate.
9. A gate valve according to claim 1 , in which the bearing member comprises sealing plates.
10. A sealing plate according to claim 1 , in which the aperture is generally circular.
11. A gate valve according to claim 1 , in which the bearing member is formed from polyethylene terephthalate.
12. A gate valve according claim 1 , in which the gate is moveable between the first and second positions by actuating means.
13. A gate valve according to claim 12 , in which the actuating means comprise pneumatic means or a handwheel.
14. A gate valve according to claim 1 , in which the body comprises side support rails for supporting an actuating means.
15. A gate valve as claimed in claim 14 , in which the support rails comprise means for engaging a housing section and means for supporting the actuating means.
16. A gate valve as claimed in claim 1 , in which the valve body comprises a mouth for receiving the gate and within which the gate slides, in which the mouth comprises a packing gland formed from an elastomeric material.
17. A gate valve as claimed in claim 1 , in which the frame has a trapezoidal-like section.
18. A gate valve as claimed in claim 17 , in which the trapezoidal-like section has parallel longer and shorter sides, and in which the mat can be orientated so that the shorter side is in contact with the bearing member.
19. A gate valve as claimed in claim 1 , in which the framework defines hexagonal cut-outs.
20. A gate valve as claimed in claim 1 , in which the mat is generally rectangular.
21. A gate valve as claimed in claim 20 , in which the mat includes a circular aperture at one end thereof.
22. A gate valve comprising:
a valve body including an aperture,
a gate reciprocally movable within the body between a first position in which the aperture is occluded and a second position in which the aperture is open,
the valve body comprises two complimentary housing sections,
each housing section has a respective bearing member in contact with a major surface of the gate and over which the gate moves in the body, and
each housing section has a respective a loading member arranged to urge its respective bearing member against the major surface of the gate,
in which each loading member comprises a lattice-like elastomeric mat, the mat comprising a framework which defines a plurality of cut-outs and the framework has a cross section with chamfered sides.