Two-door elevator

Abstract

An elevator assembly for moving a tubular member, the elevator assembly comprising first and second doors each connected to a front side of a body such that the first and second doors rotate between open and closed positions, wherein the body and the doors collectively encircle the tubular member when the doors are in the closed position, and wherein a center of mass of the elevator assembly remains substantially unchanged regardless of whether the first and second doors are in the open or closed position.

1 . An elevator assembly for moving a tubular member, comprising: 
 first and second doors each connected to a front side of a body such that the first and second doors rotate between open and closed positions, wherein the body and the doors collectively encircle the tubular member when the doors are in the closed position, and wherein a center of mass of the elevator assembly remains substantially unchanged regardless of whether the first and second doors are in the open or closed position.    
   
   
       2 . The elevator assembly of  claim 1  further comprising first and second spring-locking assemblies configured to lock the first and second doors, respectively, in the closed position.  
   
   
       3 . The elevator assembly of  claim 2  wherein the first and second spring-locking assemblies each include a locking pin biased towards the corresponding first or second door and configured to be received within a locking aperture of the first or second door when the first or second door is in the closed position.  
   
   
       4 . The elevator assembly of  claim 1  further comprising a load-locking assembly configured to lock the doors in the closed position upon application of an axial load to the elevator assembly.  
   
   
       5 . The elevator assembly of  claim 4  wherein the load-locking assembly comprises a load-locking cavity located in the first door and a load-locking projection extending from the second door, and wherein the application of the axial load results from the weight of the tubular member and causes the load-locking projection to enter the load-locking cavity.  
   
   
       6 . The elevator assembly of  claim 1  further comprising first and second actuators operable to open and close the first and second doors, respectively.  
   
   
       7 . The elevator assembly of  claim 6  wherein the actuators are hydraulic actuators.  
   
   
       8 . The elevator assembly of  claim 6  wherein the actuators are pneumatic actuators.  
   
   
       9 . A method for moving a tubular member, comprising: 
 orienting an elevator assembly around the tubular member such that the axis of the elevator assembly is substantially aligned with the axis of the tubular member;    closing the elevator assembly around the tubular, wherein the elevator assembly comprises first and second doors each connected to a front side of a body such that the first and second doors rotate between open and closed positions, wherein the body and the doors collectively encircle the tubular member when the doors are in the closed position, and wherein a center of mass of the elevator assembly remains substantially unchanged regardless of whether the first and second doors are in the open or closed position; and    locking the elevator assembly doors in the closed position.    
   
   
       10 . The method of  claim 9  wherein closing the elevator assembly comprises pneumatically operating first and second actuators operable to open and close the first and second doors.  
   
   
       11 . The method of  claim 9  wherein closing the elevator assembly comprises hydraulically operating first and second actuators operable to open and close the first and second doors.  
   
   
       12 . The method of  claim 9  wherein locking the elevator assembly doors in the closed position comprises inserting first and second locking pins into corresponding first and second cavities, respectively, in the first and second doors, respectively.  
   
   
       13 . The method of  claim 9  wherein locking the elevator assembly doors in the closed position comprises applying an axial load to a top part of the second door thereby translating the top part of the second door towards a bottom part of the second door resulting in the insertion of a locking projection extending from the top part of the second door into a corresponding cavity in the first door.  
   
   
       14 . An elevator assembly for moving a tubular member, comprising: 
 first and second doors each connected to a front side of a body such that the first and second doors rotate between open and closed positions, wherein the body and the doors collectively encircle the tubular member when the doors are in the closed position; and    first and second spring-locking assemblies configured to lock the first and second doors, respectively, in the closed position.    
   
   
       15 . The elevator assembly of  claim 14  wherein the first and second spring-locking assemblies each include a locking pin biased towards the corresponding first or second door and configured to be received within a locking aperture of the first or second door when the first or second door is in the closed position.  
   
   
       16 . The elevator assembly of  claim 14  further comprising a load-locking assembly configured to lock the doors in the closed position upon application of an axial load to the elevator assembly.  
   
   
       17 . The elevator assembly of  claim 16  wherein the load-locking assembly comprises a load-locking cavity located in the first door and a load-locking projection extending from the second door, and wherein the application of the axial load results from the weight of the tubular member and causes the load-locking projection to enter the load-locking cavity.  
   
   
       18 . The elevator assembly of  claim 14  further comprising first and second actuators operable to open and close the first and second doors, respectively.  
   
   
       19 . The elevator assembly of  claim 18  wherein the actuators are hydraulic actuators.  
   
   
       20 . The elevator assembly of  claim 18  wherein the actuators are pneumatic actuators.