Abstract: A labyrinth barrier is disclosed and comprises two or more members each defining respective vertical axes. One or more of the members are constructed at least in part of a shape memory material having a first energy state and a second energy state. The members are oriented relative to one another by their respective vertical axes in an original state to create a flow pathway that restricts fluid flow in a direction transverse to the respective vertical axes. The members are urged towards one another to further restrict the flow pathway when the shape memory material transitions from the first energy state to the second energy state.

Abstract: An aircraft door sealing system comprises a resilient sealing element secured to an aircraft door arrangement first element and comprising a sealing lip extending from a sealing member. A rigid counter-bearing element is secured to an aircraft door arrangement second element and cooperates with the sealing element to seal a gap between the first and second elements. The counter-bearing element comprises a first portion cooperating with the sealing member and a second portion cooperating with the sealing lip. The sealing lip and the second portion are positioned relative to each other, and the sealing lip can be resiliently deformed, so that the sealing lip is applied to the second portion and a contact face between the sealing lip and the second portion is formed or increases, when an external pressure acting on an outer face of the sealing lip via the gap, exceeds a threshold value.

Abstract: An aircraft door, and, more particularly, to a mounting system for a pressure seal of an aircraft door. A mounting system may include an outer skin, a pressure seal, a clamping component, a pressure seal fastener having a head and a threaded shank, a nut, a mounting support having a clearance hole that is adapted to prevent a rotational and axial movement of the pressure seal fastener, and mounting support fasteners. Mounting support fasteners removably attach the mounting support to the outer skin. The head of the pressure seal fastener is connected to the mounting support such that a rotational and axial movement of the pressure seal fastener is prevented. The nut is removably attached to the threaded shank of the pressure seal fastener, thereby removably clamping the pressure seal between the clamping component and the mounting support.

Abstract: A non-metallic engine case inlet compression seal for a gas turbine engine includes a non-metallic longitudinal leg section that extends from the non-metallic arcuate interface section and a non-metallic mount flange section that extends from the longitudinal leg section.

Abstract: An inflatable seal system with retractable load bearing feature providing sealing in the annulus between a ball inside a pipe, with minimal pressure applied to inflate the inflatable seal, by using a retractable load bearing construct to hold the ball in place against the high-pressure forces in the pipe.

Abstract: Embodiments of the invention provide a sealing system configured to provide a sealed boundary between a conditioned and an uncontrolled or separately conditioned environment. In some examples, the sealing system may comprise a door, a conditioning device, and a seal assembly. The door may be moveable between an opened position and a closed position. The seal assembly may be coupled to the door and have an airflow path. When the door is in the closed position, the conditioning device may be configured to direct conditioned air into the airflow path, thereby urging conditioned air through the seal to inhibit undesirable door and/or adjacent surface conditions.

Abstract: Embodiments are directed to systems and methods for a sliding door in a pressurized aircraft. In one embodiment, an aircraft comprises a fuselage having a door opening, and a door configured to slide into the door opening from within the fuselage, the door held in a closed position in the door opening by excess air pressure within the fuselage during operation of the aircraft.

Abstract: An inflatable, window-covering system is described. The inflatable, window-covering system may include an inflatable cushion and a drive assembly, the drive assembly including a power source; one or more sensors, where the one or more sensors may be configured to detect a triggering event; and an air pump configured to inflate the inflatable cushion based, at least in part, on the detected triggering event. In some cases, the triggering event may include any of sensing a predetermined temperature, sensing a predetermined level of light intensity, sensing a predetermined time, or receiving an instruction, or any combination thereof.

Abstract: Disclosed herein is a seal assembly for sealing a gap between a first component and a second component is disclosed. The second component is movable relative to the first component. The seal assembly includes a rub strip and a seal strip. The rub strip includes a seal strip engagement surface having a convex shape. Additionally, the rub strip includes a first component engagement surface that is opposite the seal strip engagement surface and has a concave shape. The seal strip includes a rub strip engagement surface having a convex shape. Furthermore, the seal strip includes a second component engagement surface that is opposite the rub strip engagement surface and has a concave shape. The seal strip engagement surface is harder than the rub strip engagement surface.

Abstract: A bearing having an inner ring, an outer ring, and sealing means is provided. The bearing includes a complementary inflatable sealing device mounted on one of the rings and further includes a fixed annular part and a deformable annular portion coupled to the annular fixed part that can be deformed in a direction from a retracted position to a deployed position under the effect of a fluid and in the other direction towards its retracted position, at least one annular chamber for receiving the fluid, into which the orifice being formed between the fixed and deformable portions at least when the deformable annular portion is extended axially.

Abstract: An aircraft door includes an outer shell with an exterior and an interior, a stiffening structure arranged on the interior of the outer shell, and at least one door seal arranged on the interior of the outer shell. The door seal is circumferential in an edge region. In the edge region between the outer shell and the door seal at least one circumferential stiffening component is arranged that is connected to the stiffening structure. Thus, in a particularly simple manner and without modifications to a stiffening structure, an aircraft door may be provided with very substantial stiffness in an edge region.

Abstract: A roll-up door assembly including a plurality of door panels; a pneumatic seal apparatus having an elastic membrane of an elongated tube disposed around a perimeter of the trailer door so as to be adjacent to the plurality of door panels, wherein pressurized air is injected into the pneumatic seal apparatus to expand the elastic membrane and to apply an outward force against multiple sides of the plurality of door panels, wherein applying the outward force against the plurality of door panels on multiple sides keeps the plurality of door panels as a single unit such that substantially less air flows through the plurality of door panels than prior to the application of the outward force to seal the trailer door.

Abstract: Device for closing an opening in a chamber wall of a low-pressure or vacuum chamber, having at least one movably mounted closure element, a main body with a through-opening and a seat, which surrounds the through-opening, the through-opening is congruent with the opening in the chamber wall, and the device has at least one open position of the closure element, in which the through-opening is exposed by the closure element, and at least one closed position, in which the through-opening is completely closed using the closure element. At least one elastic seal with an inflatable chamber is sealingly arranged in the closed position between the closure element and the seat and the elastic seal has in addition to the inflatable chamber a safety chamber for receiving fluid from the inflatable chamber in the event of a leak in the inflatable chamber.

Abstract: A door seal for a doorway in a vehicle for public passenger transportation has at least one reinforcing element coated with an elastomer, the reinforcing element having a lesser elasticity in the longitudinal direction of the seal than in the transverse direction.

Abstract: A door opening unit for automatically opening a door for a dishwasher includes an actuator, a link member that makes a straight motion due to pressurization of the actuator and has a plurality of legs, a plurality of rotation levers that are connected to the plurality of legs of the link member, and a plurality of pressurization members that are connected to the plurality of rotation levers. Since the plurality of pressurization members may pressurize a plurality of points of the door, the door may be more smoothly opened. Also, the door opening unit for automatically opening the door includes a restoring spring that restores positions of the plurality of pressurization members when power to the actuator is turned off.

Abstract: An apparatus for sealing a fan drive shaft in a vacuum heat treating furnace is disclosed. The sealing apparatus includes a housing having an annular body and a central opening. An inflatable first seal surrounds the central opening of the annular body. A second seal surrounds the central opening and is adjacent to the inflatable first seal. The sealing apparatus also includes a channel formed in the annular body adjacent to the second seal for conducting a purging fluid into the central opening. A means for injecting the purging fluid into the central opening is operably connected to the channel. A vacuum heat treating furnace and a fan drive system incorporating the sealing apparatus are also described.

Abstract: A cover plate for covering a door clearance between a skin of a means of transportation and a door as well as a door arrangement with such a cover plate is proposed. The cover plate includes a mounting region for permanently fastening the cover plate on the door; a covering region for covering the door clearance; and a fastening device that is designed for fixing the covering region on the skin when the door is closed.

Abstract: A waterproof lockable door and an automatic pressure adjusting plug set thereof are provided. An electronic device is formed with an opening having an annular wall. The waterproof lockable door includes a cover member formed with at least a penetrated hole and an automatic pressure adjusting plug set including a waterproof member and at least a fastening unit. The waterproof member is formed with at least a fasten hole. The fastening unit is formed with a head portion and a rod portion, and the rod portion is received in the penetrated hole and generates a movement relative to the cover member thereby driving the outer periphery of the waterproof member to be tightly adjacent to annular wall. Accordingly, the tolerance of the annular wall and the waterproof member and the air pressure inside an opening both force the waterproof member to move.

Abstract: A device (100) for closing an opening in a room has a frame (102) in the reveal of the room opening and at least one leaf (104) which is arranged movably with respect to the frame (102) and is movable with respect to the frame into a closure position in which there is, between the frame (102) and the leaf (104), a gap (112) which can be sealed by means of a deformable and/or movable sealing member (114). A sealing member actuating device (120), by means of which the sealing member (114) can be deformed and/or moved, is arranged in the frame (102) and/or in the leaf (104) in order to seal the gap (112).

Abstract: A door seal for a doorway in a vehicle for public passenger transportation has at least one reinforcing element coated with an elastomer, the reinforcing element having a lesser elasticity in the longitudinal direction of the seal than in the transverse direction.

Abstract: A sliding door device for a vehicle includes a sliding door installed to be slidingly moved, a door weather strip attached to the sliding door, a pressure switch for sensing internal pressure of the door weather strip, a pneumatic line for connecting the door weather strip and the pressure switch to communicate with each other, an electronic control unit (ECU) for receiving a sensing signal of the pressure switch to control opening and closing of the sliding door, and an opening and closing valve for having the pneumatic line communicate with the atmospheric pressure or blocking the pneumatic line from the atmospheric pressure. Therefore, it is possible to effectively prevent an object or an occupant from being jammed in a process of closing the sliding door.

Abstract: A seal assembly is provided for maintaining a pressure difference between an exterior and an interior of an object having an access hatch and an access hatch frame. The seal assembly has a seal retainer having an interior face oriented toward the interior of the object, an exterior face oriented toward the exterior of the object, a hatch-side face oriented toward the access hatch and extending from the interior face to the exterior face, and frame-side face oriented toward the access hatch frame and extending from the interior face to the exterior face. The seal assembly also has at least one sealing member mounted on either the interior face or the exterior face of the seal retainer and a plurality of conduits formed in the seal retainer and extending from the exterior face to the interior face.

Abstract: A sealing system for doors and windows includes a reservoir device, a sealing tube configured to expand and to contract, and a transfer valve configured to couple the reservoir device to a first end of the sealing tube. Responsive to either of a door or window closing, a medium may be transferred from the reservoir device via the transfer valve to the sealing tube. Responsive to receiving the medium, the sealing tube may expand to substantially seal a gap between an edge of either of the door or the window and a surface in proximity to the edge. Responsive to either of the door or window opening, the medium may be discharged from the sealing tube via the transfer valve. The sealing tube may contract in response to discharging the medium.

Abstract: Pneumatic door system of fluid lines, valves, switches, and sensors integrated into hinge mechanisms, door frame, and door connected to a fluid pressurization system to inflate and deflate one or more fluid seals attached to outer perimeter of door adjacent to inner perimeter of door frame to close gap between outer perimeter of door and inner perimeter of door frame to provide radio frequency shielding against, for example, high-altitude electromagnetic pulse. Air seal creates a substantially impermeable barrier against radio frequency transmission, as well as air infiltration, when fully inflated. Separate fluid channels in each component interconnect to act as one fluid circuit or network when door is closed. Pneumatic door system can be fluidly connected to a conventional fluid pressurization system in communication with a programmable logic controller to respond to user input or automatic commands with system overrides to react to system air pressure and air flow conditions.

Abstract: A steam autoclave (steam sterilization system) has a door for opening and closing an opening that defines the entrance to and exit from a steam sterilization chamber. The door may be latched and locked and pneumatically sealed when in a closed position. Preferably, the door has a convex portion that projects into the sterilization chamber when the door is in a closed position for aiding in providing an even distribution of steam throughout the sterilization chamber during operation of the steam autoclave.

Abstract: Active seal architectures adapted for producing a variable sealing and/or closing force between a closure panel and perimeter, includes a mounting clip, a flexible outer layer fixedly connected to the clip, defining an interior space, and longitudinally extending along the perimeter; and an interior structure comprising and reconfigurable by an active material disposed within the space, and operable to impart differing first and second forces upon the layer and panel when the material is activated and deactivated respectively.

Abstract: Pneumatic door system of fluid lines, valves, switches, and sensors integrated into hinge mechanisms, door frame, and door connected to a fluid pressurization system to inflate and deflate one or more fluid seals attached to outer perimeter of door adjacent to inner perimeter of door frame to close gap between outer perimeter of door and inner perimeter of door frame to provide radio frequency shielding against, for example, high-altitude electromagnetic pulse. Air seal creates a substantially impermeable barrier against radio frequency transmission, as well as air infiltration, when fully inflated. Separate fluid channels in each component interconnect to act as one fluid circuit or network when door is closed. Pneumatic door system can be fluidly connected to a conventional fluid pressurization system in communication with a programmable logic controller to respond to user input or automatic commands with system overrides to react to system air pressure and air flow conditions.

Abstract: The subject invention relates to a protective window covering system comprising a conventional building window having a window frame and an inflatable protective window covering, wherein multiple hooks are mounted around the perimeter of the window frame, wherein the inflatable protective window covering is comprised of a single, uninterrupted inner cavity and walls wherein the walls of the protective covering enclose the inner space of the protective covering, and wherein the walls of the protective covering include at least two rows of fibers extending throughout at an angle that is offset by 15° to 75°, and a securing means wherein the securing means attaches loosely to the window frame in an uninflated state, wherein inflation of the protective covering applies tension to the securing mechanism thereby securing the protective covering.

Abstract: A vehicle and method of operation having a first door, a second door, an inflatable door seal assembly and an inflator assembly. The first door has a first opening side and a first seal mount extending along the first opening side. The second door has a second opening side adjacent to the first opening side to define a gap and a second seal mount extending along the second opening side. The door seal assembly has a first seal assembly mounted to one of the first or second seal mounts, the first seal assembly inflatable to extend into the gap toward the other of the seal mounts when the first and second door are closed and deflatable to retract from the gap. The inflator assembly pumps a fluid into the seal assembly to inflate the seal assembly and pumps the fluid out to deflate the seal assembly.

Abstract: Radio-frequency (RF) leakage from shielded enclosures is minimized while ensuring applicable RF attenuation standards and access requirements of the Americans with Disabilities Act (ADA) by attaching an inflatable bladder to a door of an enclosure. Substantially surrounding the bladder is an electrically conductive material. When the bladder is inflated it makes contact with conductive material which in turn makes conductive contact with the door frame to create an RF seal. The use of the bladder and conductive material provides an improved RF seal and allows for the use of a low-profile threshold that permits ADA access to, and from, the enclosure.

Abstract: An ejection system for a window pane or panel which is affixed to a frame structure with at least one clamping seal. The system has means for ejecting the panel or window pane from the clamping seal and (a) a frame part with a housing which surrounds the inner face of the window pane or panel along a peripheral path, wherein the housing has an open end facing the window pane or panel; (b) an inflatable seal arranged in the housing; (c) a pressure source which is joined to the inflatable seal; and (d) an emergency actuation means to release pressure from the gas pressure source. The released air or gas expands the inflatable seal which pushes the window pane or panel out of the clamping seal.

Abstract: A vehicle and method of operation having a first door, a second door, an inflatable door seal assembly and an inflator assembly. The first door has a first opening side and a first seal mount extending along the first opening side. The second door has a second opening side adjacent to the first opening side to define a gap and a second seal mount extending along the second opening side. The door seal assembly has a first seal assembly mounted to one of the first or second seal mounts, the first seal assembly inflatable to extend into the gap toward the other of the seal mounts when the first and second door are closed and deflatable to retract from the gap. The inflator assembly pumps a fluid into the seal assembly to inflate the seal assembly and pumps the fluid out to deflate the seal assembly.

Abstract: A door seal arrangement and method for sealing between a door and a door frame on food processing equipment are provided. The door seal is inflatable to create a seal between the door and the door frame and deflatable to release the seal between the door and the door frame. An air supply applies positive air pressure to the door seal to inflate the door seal. A vacuum applies a negative air pressure to the door seal to deflate the door seal.

Abstract: Device for closing an opening in a chamber wall of a low-pressure chamber or vacuum chamber, which has at least one movably mounted closure element (1), at least one main body (2) with a through-opening (3) and at least one seat (4), which surrounds the through-opening (3), wherein the through-opening (3) can be made congruent or is congruent with the opening in the chamber wall, and wherein the device has at least one open position of the closure element (1), in which the through-opening (3) is exposed by the closure element (1), and at least one closed position of the closure element (1), in which the through-opening (3) is completely closed using the closure element (1), and has at least one elastic seal (5) with at least one inflatable chamber (6), wherein, in the closed position, the seal (5) is arranged between the closure element (1) and the seat (4) and the closure element (1) is sealed with respect to the seat (4) and wherein the elastic seal (5) has in addition to the inflatable chamber (6) at least

Abstract: A seal that includes a hollow bulb that defines an interior space, and further includes at least one solid divider wall located in the interior space in order to divide the interior space so that it includes at least a first chamber and a second chamber, where the first and second chambers are not in fluid communication with one another. In some preferred embodiments: (i) the interior wall is generally V-Shaped in transverse cross-section; (ii) the first chamber is generally triangular in transverse cross-section; and (iii) the second chamber is generally U-shaped in transverse cross-section. Some preferred embodiments further include a seal base (for example, a T-shaped base), with the hollow bulb being mechanically connected to the base at the bottom of the T-shape so that an open end of the V-shaped interior wall is oriented to directly face the seal base. In some preferred embodiments, the first and second chambers are hollow.

Abstract: Protective containers for electronic equipment, and methods of testing and manufacture thereof, are provided. The cabinets provide a HEMP protection level to electronic equipment housed therein that meets a HEMP protection level according to MIL-STD-188-125-1.

Abstract: A method and apparatus for fireproofing a doorway, more particularly, the present invention relates to a gasket structure capable of sealing a doorway in the event of a fire. The gasket structure includes an outer silicon rubber core having a substantially D-shaped cross-section for mounting to a gasket retainer with a substantially U-shaped channel to a door frame. The gasket also includes an inner core of intumescent material within the outer core. The gasket is designed so that if the outer silicone rubber deteriorates because of fire, the intumescent material undergoes voluminous expansion to fill up voids left by the deterioration of the outer silicone rubber.

Abstract: The present invention provides a sterilizer having a housing defining a sterilization chamber. An opening in the housing communicates with the chamber. A surface surrounds the opening, and a door is movable between one of an open position allowing access to the chamber through the opening and a closed position covering the opening. A seal element is associated with the surface for forming a fluid-tight seal between the door and the surface when the door is in the closed position. An operating system is provided for applying pressure to one side of the seal from a first source external to the operating system to force the seal into engagement with the door. Sensing means are provided for monitoring the pressure applied to the seal from the first pressure source. A second source of pressure is provided in the operating system and is connectable to the seal.

Abstract: A door arrangement for tightly closing a door opening comprises a door frame, a door which, when closed, is arranged in the door frame, and inner and outer sealing lips. The inner and outer sealing lips run next to each other along a periphery of the door opening between a first surface of the door and a second surface of the door frame, wherein the first and second surfaces face each other. The inner and outer sealing lips bound a space formed between them. The door arrangement further comprises a pressure-reducing device configured to reduce pressure in the space.

Abstract: Pneumatic door system of fluid lines, valves, switches, and sensors integrated into hinge mechanisms, door frame, and door connected to a fluid pressurization system to inflate and deflate one or more fluid seals attached to outer perimeter of door adjacent to inner perimeter of door frame to close gap between outer perimeter of door and inner perimeter of door frame to provide radio frequency shielding against, for example, high-altitude electromagnetic pulse. Air seal creates a substantially impermeable barrier against radio frequency transmission, as well as air infiltration, when fully inflated. Separate fluid channels in each component interconnect to act as one fluid circuit or network when door is closed. Pneumatic door system can be fluidly connected to a conventional fluid pressurization system in communication with a programmable logic controller to respond to user input or automatic commands with system overrides to react to system air pressure and air flow conditions.

Abstract: A seal assembly is provided for maintaining a pressure difference between an exterior and an interior of an object having an access hatch and an access hatch frame. The seal assembly has a seal retainer having an interior face oriented toward the interior of the object, an exterior face oriented toward the exterior of the object, a hatch-side face oriented toward the access hatch and extending from the interior face to the exterior face, and frame-side face oriented toward the access hatch frame and extending from the interior face to the exterior face. The seal assembly also has at least one sealing member mounted on either the interior face or the exterior face of the seal retainer and a plurality of conduits formed in the seal retainer and extending from the exterior face to the interior face.

Abstract: A weatherseal adapted to be installed in a door or window opening includes a spine, a resilient foam core, an intumescent material, and a liner. The spine has first and second ends, the first end adapted for mounting the weatherseal to the door or window opening. The resilient foam core is attached to the spine, proximate the second end of the spine. The intumescent material is arranged proximate the foam core. The liner encloses the flexible foam core and the intumescent material. The weatherseal or a portion may be color-coded to identify the weatherseal for fire rated applications.

Abstract: A closure assembly with a shape memory polymer seal is provided for use with a vehicle. The closure assembly includes a frame member configured for attachment to the vehicle body to selectively transition from a closed position to an open position. The seal structure includes a base portion elongated along and attached to a peripheral edge of the frame member or the vehicle body, and a flexible contact portion extending integrally from the base portion and configured for sealing communication with an opposing surface. A thermally-activated smart material (TASM), namely a shape memory polymer member, is disposed inside a cavity within the contact portion. A thermoelectric device is in thermal communication with the TASM, and is characterized by a thermal differential when current flows therethrough. The TASM is activated in response to the thermal differential of the thermoelectric device, thereby altering at least one physical property of the TASM.

Abstract: A system used in a vertical furnace is provided that includes a tube. The tube includes a tube flange at its lower end. The tube flange provides a first sealing surface at its lower end. Further, there is a structural member at the lower surface of the tube flange. This structural member extends vertically away from the lower surface of the tube flange at a position that is displaced inwardly from the first sealing surface. The system also includes a removable door plate that provides a second sealing surface at its upper surface. The second sealing surface of the removable door plate is sealed with the first sealing surface of the tube flange.

Abstract: An example of an inflatable seal for a door includes a bi-directional airflow pattern of frost-inhibiting heated air. The bi-directional flow pattern enables the seal's discharge opening and supply air blower to both be located well above the floor and preferably above the doorway. If the discharge opening is near the suction inlet of the blower, such an arrangement makes it possible to recover previously heated air by returning some of the warm air back to the blower. In some examples, the seal includes a supply air conduit and a return air conduit with one disposed within the other. The internal conduit may include a relatively stiff elbow to prevent that conduit from becoming kinked near an upper corner of the door.

Abstract: Gate with an at least partially peripheral sealing means, with a retaining strip made from metal, within which the seal is arranged, wherein the seal may be activated pneumatically, with an adjustable plate which is located above the seal and is guided by guide means so as to be adjustable relative to the retaining strip, with an electrically conductive fabric strip which electrically connects the retaining strip to the plate, and with spring contacts which are arranged on the plate, are electrically conductive and may be brought into abutment with the rabbet of the installation frame provided on the building side.

Abstract: Active seal architectures adapted for producing a variable sealing and/or closing force between a closure panel and perimeter, includes a mounting clip, a flexible outer layer fixedly connected to the clip, defining an interior space, and longitudinally extending along the perimeter; and an interior structure comprising and reconfigurable by an active material disposed within the space, and operable to impart differing first and second forces upon the layer and panel when the material is activated and deactivated respectively.

Abstract: A door for a cold storage locker or other applications includes an inflatable or fluid-filled seal system. The seal system comprises a network of pliable tubular seals that expand as air or another fluid is forced air through the seals. Expansion of the seals provides a more positive seal. To inhibit frost from accumulating near the seals, the seals are kept relatively warm by continuously circulating fluid through the seals regardless of whether the door is open or closed. In some cases, the fluid within the seals is heated.

Abstract: Gasket for refrigerator cabinets of the kind including a soft bellows-type portion used for sealing the area between the cabinet and the door, thus extending from a base portion able to match the outer door and/or inner door of the refrigerator cabinet, wherein said base portion is substantially rigid and that at one end of it there is a means made of substantially soft material extending toward said inner door, said material having good flexible and spring back features when exposed to refrigerator and freezer temperatures, able to further seal, preferably by compression, the space located between said cabinets and inner door in a more internal area of the refrigerator cabinet, wherein said sealing means is independent and free from constraints with respect to said soft bellows-type portion.

Abstract: A system used in a vertical furnace is provided that includes a tube. The tube includes a tube flange at its lower end. The tube flange provides a first sealing surface at its lower end. Further, there is a structural member at the lower surface of the tube flange. This structural member extends vertically away from the lower surface of the tube flange at a position that is displaced inwardly from the first sealing surface. The system also includes a removable door plate that provides a second sealing surface at its upper surface. The second sealing surface of the removable door plate is sealed with the first sealing surface of the tube flange.