Closure system for a pressure vessel

Abstract

A closure system which provides a lubricated lock ring on a hinged door assembly rather than proximate a pressure vessel is provided. The configuration of this system removes lubricants from the region immediately adjacent a pressure vessel entrance to be sealed by the door assembly. A shorter entrance tunnel for access to the pressure vessel interior is also provided by this configuration. A clamp ring having radially extending lugs is rigidly affixed proximate to and partially defining the pressure vessel entrance. The door has a continuous thread about an outer circumferential surface thereof. A lock ring having a complementary interior continuous thread is in rotational communication with the threaded circumferential surface of the door. The lock ring also has plural, inwardly projecting lugs which are capable of passing between the clamp ring lugs when the door is swung toward the clamp ring. The lock ring is capable of being rotated by a rotary actuator for engagement of the clamp ring lugs with the lock ring lugs. The door may be provided with a sight glass and light source for viewing the interior of the pressure vessel. The door may also be provided with a face plate on the door for maintaining the lock ring in concentric alignment with the door to prevent the cooperating threads from binding. Limit switches may be employed to detect when clamp ring and lock ring lugs are aligned for door closure, and when the lock ring is rotated by the desired amount. A proximity sensor may be provided for making sure the door is in a closed position before enabling lock ring rotation.