Pig Receiver Assembly

Abstract

A pig receiver and methods to operate the pig receiver in pipeline pigging operations. In one embodiment, a pig receiver includes a pig receiver unit, The pig receiver also includes a pig gate valve assembly disposed on the pig receiving unit. The pig gate valve assembly includes a gate valve. The pig gate valve assembly also includes a rod, wherein the gate valve is attached to the rod at a longitudinal end of the gate valve. The pig gate valve assembly further includes a gate housing, wherein the rod is disposed within the gate housing. In addition, the pig gate valve assembly includes a cylinder guide, wherein the cylinder guide extends longitudinally from the gate housing. The pig gate valve assembly also includes a first actuator and a second actuator. The pig receiver also includes a contaminant removal system.

What is claimed is: 
     
         1 . A pig receiver, comprising:
 a pig receiver unit;   a pig gate valve assembly disposed on the pig receiver unit, comprising:
 a gate valve; 
 a rod, wherein the gate valve is attached to the rod at a longitudinal end of the gate valve; 
 a gate housing, wherein the rod is disposed within the gate housing; 
 a cylinder guide, wherein the cylinder guide extends longitudinally from the gate housing; 
 a first actuator and a second actuator; and 
   a contaminant removal system.   
     
     
         2 . The pig receiver of  claim 1 , wherein the contaminant removal system comprises a manifould and fluid piping, wherein the fluid piping couples the manifould to the gate housing. 
     
     
         3 . The pig receiver of  claim 2 , wherein the contaminant removal system comprises a lubricator, wherein the lubricator is disposed on the fluid piping. 
     
     
         4 . The pig receiver of  claim 1 , further comprising a bottom valve and a support, wherein the bottom valve is disposed below the pig receiver unit and on the support, wherein the support is configured to support the weight of the pig receiver unit. 
     
     
         5 . The pig receiver of  claim 1 , further comprising a sump disposed at a bottom portion of the pig receiver unit, wherein the sump comprises:
 a sump valve;   a sump outlet;   a plurality of sump bars; and   a plurality of sump gaps, wherein an individual sump gap is disposed between adjacent sump bars.   
     
     
         6 . The pig receiver of  claim 1 , further comprising a first exhaust valve and a second exhaust valve, wherein both the first exhaust valve and the second exhaust valve comprise an exhaust silencer. 
     
     
         7 . The pig receiver of  claim 6 , wherein the first exhaust valve is disposed on the pig receiver unit between the pig gate valve assembly and a pipeline contact end of the pig receiver, wherein the second exhaust valve is disposed between the pig gate valve assembly and a pig retrieval end of the pig receiver, wherein the second exhaust valve comprises a lever. 
     
     
         8 . The pig receiver of  claim 1 , further comprising a pressure equalization system, wherein the pressure equalization system is configured to adjust a pressure in the pig receiver unit downstream of the gate valve. 
     
     
         9 . The pig receiver of  claim 8 , wherein the pressure equalization system comprises:
 a pressure equalization valve;   an upstream connection, wherein the upstream connection is connected to the pig receiver unit upstream of the gate valve;   a downstream connection, wherein the downstream connection is connected to the pig receiver unit downstream of the gate valve;   a first pressure gauge, wherein the first pressure gauge is disposed at the upstream connection; and   a second pressure gauge, wherein the second pressure gauge is disposed at the downstream connection.   
     
     
         10 . The pig receiver of  claim 9 , further comprising a pressure line, wherein the pressure line is coupled to the upstream connection and the downstream connection, wherein the pressure equalization valve is disposed on the pressure line. 
     
     
         11 . A method for operating a pig receiver, the method comprising:
 closing a gate valve of the pig receiver, wherein the pig receiver comprises:
 a pig receiver unit; 
 a pig gate valve assembly disposed on the pig receiver unit, comprising:
 the gate valve; 
 a rod, wherein the gate valve is attached to the rod at a longitudinal end of the gate valve; 
 a gate housing, wherein the rod is disposed within the gate housing; 
 a cylinder guide, wherein the cylinder guide extends longitudinally from the gate housing; 
 a first actuator and a second actuator; and 
 
 a contaminant removal system; 
   opening a pressure equalization valve of the pig receiver;   adjusting a pressure downstream of the gate valve; and   equalizing the pressure downstream of the gate valve with a pressure upstream of the gate valve.   
     
     
         12 . A method for operating a pig receiver, the method comprising:
 flowing a fluid to the pig receiver, wherein the pig receiver comprises:
 a pig receiver unit, wherein a bottom valve is disposed below the pig receiver unit; 
 a sump, wherein the sump is disposed at a bottom portion of the pig receiver unit; 
 a pig gate valve assembly disposed on the pig receiver unit, comprising:
 a gate valve; 
 a rod, wherein the gate valve is attached to the rod at a longitudinal end of the gate valve; 
 a gate housing, wherein the rod is disposed within the gate housing, wherein the gate housing comprises a gate sealing area; 
 a cylinder guide, wherein the cylinder guide extends longitudinally from the gate housing; 
 a first actuator and a second actuator; and 
 
 a contaminant removal system; 
   contacting a surface of the pig gate valve assembly with the fluid;   flowing the fluid to the gate sealing area; and   removing contaminants from the pig receiver unit.   
     
     
         13 . The method of  claim 12 , wherein the fluid comprises air, gas, water, solvent, or any combination thereof. 
     
     
         14 . The method of  claim 13 , wherein the solvent comprises ethanol, hydrogen peroxide, or any combinations thereof. 
     
     
         15 . The method of  claim 12 , further comprising lubricating the fluid. 
     
     
         16 . The method of  claim 12 , wherein the removing contaminants comprises allowing contaminants to fall from the pig receiver unit to a bottom portion of the sump. 
     
     
         17 . The method of  claim 12 , wherein the removing contaminants comprises flowing the fluid longitudinally through the sump. 
     
     
         18 . The method of  claim 12 , wherein the contaminants include solids, obstructions, viscous material, or tar-like material. 
     
     
         19 . The method of  claim 12 , wherein the removing contaminants comprises directing the contaminants from the bottom valve to a retrieval device. 
     
     
         20 . The method of  claim 12 , wherein the removing contaminants comprises flowing the fluid to the bottom valve to provide a force to remove the contaminants.