Temporary trap door cap
A trap door cap for sealing around a trap door of a trap is disclosed. The canister includes a closed end and side walls extending from the closed end, wherein the side walls and the closed end together define a cup-shaped body having an open end opposite the closed end. The trap door cap further includes a seal configured to selectively apply a pressure-tight seal around an exterior surface of the trap at a longitudinal location of the trap inward of the trap door and a pressure-tight connection between the seal and the open end of the cup-shaped body, wherein the side walls, the closed end, the seal, and the pressure-tight connection together form a pressure-tight inner volume within the canister.
1. A trap door cap for sealing a trap, wherein the trap comprises a trap body having a longitudinal axis and a trap door assembly disposed at an open end of the trap body, wherein the trap door assembly comprises a trap door arranged to selectively seal the open end of the trap body and a connection mechanism arranged to secure the trap door to the open end of the trap body, wherein the connection mechanism has a maximum external diameter that exceeds an external diameter of the trap body, the trap door cap comprising:
a canister comprising a closed end and side walls extending from the closed end, wherein the side walls and the closed end together define a cup-shaped body having an open end opposite the closed end and wherein an inner diameter of the canister exceeds the maximum external diameter of the connection mechanism;
a seal configured to selectively apply a pressure-tight seal around a complete circumference of an exterior surface of the trap body at a longitudinal location of the trap body inward of the trap door, wherein a seal diameter of the seal at the longitudinal location is less than the inner diameter of the canister and wherein the exterior surface of the trap body at the longitudinal location is exposed when the trap door is closed; and
a pressure-tight connection between the seal and the open end of the cup-shaped body;
wherein, when the trap door cap is placed over the trap door assembly, the side walls, the closed end, the seal, and the pressure-tight connection together form a pressure-tight inner volume enclosing the trap door assembly within the canister.
2. The trap door cap of claim 1 , further comprising a controllable valve mounted on the canister and providing selective communication between the pressure-tight inner volume and an exterior of the canister.
3. The trap door cap of claim 1 , wherein the seal comprises a deformable annular rim.
4. The trap door cap of claim 3 , wherein the deformable annular rim comprises an elastically deformable material.
5. The trap door cap of claim 3 , further comprising a sealing material disposed on a surface of the annular rim that contacts the exterior surface of the trap body.
6. The trap door cap of claim 3 , wherein the pressure-tight connection comprises an integral connection between the deformable annular rim and the open end of the canister.
7. The trap door cap of claim 6 , wherein the canister and the deformable annular rim comprise an elastically deformable material.
8. The trap door cap of claim 1 , wherein the canister comprises a first component, a second component, and a fastener that selectively secures the first component to the second component.
9. The trap door cap of claim 8 , wherein the first component and the second component are divided along a plane extending through the open end and the closed end of the cup-shaped body.
10. The trap door cap of claim 9 , wherein the first component and the second component are symmetrical.
11. The trap door cap of claim 8 , wherein the seal comprises a first component annular rim portion and a second component annular rim portion.
12. The trap door cap of claim 11 , further comprising a sealing material disposed on a surface of the first component annular rim portion and the second component annular rim portion that contact the exterior surface of the trap.
13. The trap door cap of claim 1 , wherein the seal comprises a clamshell clamp removably clampable to the exterior surface of the trap body at the longitudinal location.
14. The trap door cap of claim 13 , wherein the clamshell clamp comprises a first clamshell part, a second clamshell part, and a fastener to selectively fasten the first clamshell part to the second clamshell part.
15. The trap door cap of claim 14 , wherein the fastener comprises a plurality of bolts and wherein a tightness of the plurality of bolts controls a compression of the clamshell clamp.
16. The trap door cap of claim 13 , wherein the pressure-tight connection comprises a first flange extending laterally from the clamshell clamp, a second flange formed on the open end of the canister, and a flange connector to selectively fasten the first flange to the second flange.
17. The trap door cap of claim 16 , further comprising a sealing material disposed between the first flange and the second flange.
18. The trap door cap of claim 16 , wherein the flange connector comprises a plurality of bolts and wherein a tightness of the plurality of bolts controls a compression of the first flange to the second flange.
19. The trap door cap of claim 13 , further comprising a sealing material disposed on a surface of the clamshell clamp that contacts the exterior surface of the trap body.