PRODUCT USES & ADVANTAGES
SELECT INHIBITED SOLUBLE PIGSTM are used to clean out paraffin deposits and other unwanted accumulations inside of pipes.
SELECT INHIBITED SOLUBLE PIGSTM (oil-soluble type) contain paraffin inhibitor and pour point depressant. The residual traces of inhibitor help prevent re-deposition of paraffin for a short period of time. The pour point depressant helps the oil that contacts the pig flow easier at lower temperatures.
SELECT INHIBITED SOLUBLE PIGSTM can be used in any length lines. The ball type pigs can go around 90o turns that may stick rubber or plastic pigs and are very inexpensive as compared to rubber or plastic pigs or hot-oil treatments. Pigs do not interfere with other production and pipeline chemicals.
The dissolving rate of pigs is a function of fluid temperature, relative fluid movement, friction, and absorb ability of the crude. These conditions vary greatly with each system. The melting point for our standard pig is about 145oF. Special-order melt point pigs range from 125o to 180o. All pigs will dissolve in fluids with temperatures below their melting point (just at a slower rate). Some fluid movement past the pig is necessary to dissolve the pigs if the fluid temperature is below the pig’s melting point.
TREATMENT DETERMINATION & PROCEDURE
The number of pigs to be used is based on the amount of accumulation, length of pipe, temperature of fluid and other factors. Field experience indicate and that in short lines (500 feet or less) usually require 1 to 5 pigs and longer lines (500 feet or more) usually require 5 to 10 or more pigs. Regular periodic pigging is recommended to keep lines clean and prevent paraffin from becoming too hard or thick to remove.
THE MOST COMMON PROCEDURE
Insert pigs (one at a time) through a pig launcher then pump through system and continue running pigs (one at a time) into the line until:
- no additional decrease in flowing pressure or
- no additional increase in flowing rate or
- no additional accumulation is removed downstream.
If desired, the amount of fluid pushing the pig can be measured to determine the pig location. Do not use more than one pig at a time. ALWAYS record the volume of the fluid behind the pig as “insurance” so that the pig location can be calculated should it become stuck. Applying heat to the pipe can melt the pig. ALWAYS have the capability to pump from the opposite end of the lines to free an obstruction.
THE MOST COMMON SIZE PIGS ARE LISTED BELOW. Call for quotations, if a special BALL is desired. PLUGS can be made to any specification desired.
WHEN ORDERING PIGS SPECIFY: (1) Quantity (2) Pipe Inside Diameter and schedule (3) Oil-soluble or water-soluble (4) Balls or Plugs EXAMLPLE: 6 cases, 2” schedule 40 (ID 2.067”), oil-soluble balls.
Pigs should be grooved on edges if there is a possibility that the pig could become stuck. This would allow some fluid movement past the pig on the edges.
Pigs can also be drilled in the center from each end; but leave an area in the center that is not drilled. This allows circulation to be established by raising pressure and breaking un-drilled portion of pig (center of the pig).
|Schedule 40 and Schedule 80 Pipe|
|Pipe Size||Pipe I.D.||Pipe O.D.||
|Schd 40||Schd 80||Schd 40||Schd 80||Schd 40||Schd 80|
|1 1/4||1.380||1.278||1.364||1.262||1 5/8||1.364||1.262|
|1 1/2||1.510||1.500||1.594||1.484||1 3/4||1.594||1.484|
|2 1/2||2.469||2.323||2.420||2.273||3 1/8||2.420||2.273|
|3 1/2||3.548||3.364||3.500||3.316||4 1/8||3.500||3.316|