The used drilling fluid is pumped back to the surface where it is cleaned and purified using special machines such as a vibrating screen.
A suction line is a pipe, hose, or tube that supplies a fluid to the suction or inlet side of a pump or compressor. These types of devices are used in a variety of different configurations and may look and function slightly differently depending on the host machine in question. These lines typically supply fluids for chemical processing, cooling systems, and vacuum pump applications, and can also supply fluids essential for oil and water well drilling. They can be thin or thick, long or short; some or optimized for aggressive or corrosive fluids, while others transport mainly water. Basically, the lines can supply any product that a pump or compressor can handle, including gases and petroleum products. Well drilling mud or other liquid-solid mixtures can also be transported this way, along with adhesives and epoxies.
basic concept
Chemical processing can involve the pressurization and movement of gases or liquids.
The main function of any hose or suction line is to help facilitate the movement of fluids from one place to another. There are usually several reasons why this is important. Fluids are often used as coolants and can also be used as a source of energy. In storage situations, the lines can act as manifolds, allowing operators to test or release certain metered quantities without disrupting the main well. The lines often look like simple tubes, but they are almost always pressurized and can often function as valves, alternatively stopping or turning on the flow. When they work properly, they can regulate temperature and pressure with great precision.
Design considerations
Oil drilling uses suction line pipes to supply drilling mud to the rig.
Suction line design involves determining the required flow and proper pressure drop to prevent what is known as “starvation” of the pump or compressor. The viscosity or thickness and weight of the fluid being pumped are key design variables. Design engineers are often concerned with net positive suction head. This means having enough positive fluid pressure at the pump suction to prevent the formation of gas bubbles, called cavitation, which can damage the pump.
Pump suction can be compromised if the pump feed point is at a lower elevation than the pump or if the suction lines are too small. Another cause for concern is that too many fittings or bends can cause a pressure drop, and the wrong size can also compromise suction. Regular maintenance of suction devices such as filters or traps is usually recommended to prevent clogging and starvation of the pump.
Role in oil drilling
Oil drilling uses suction line pipes to supply drilling mud to the rig. Drilling mud is a mixture of clay and water used to cool and lubricate the drill head and to remove debris from the drill hole. A mud pit or mud tank contains the drilling mud and a suction line is connected from the mud tank to the mud supply pump to supply pressurized mud to the drilling assembly.
chemical processing applications
Chemical processing can involve the pressurization and movement of gases or liquids. The gas compressor or liquid pump draws material from storage or a previous processing step through a line, discharging the fluid to a downstream processing or storage step. Many liquid chemicals can easily vaporize if positive pressure is not maintained at the pump, so a suction tank can be installed upstream of the line to ensure adequate pressure and supply.
In Refrigeration and Air Conditioning
Refrigeration and air conditioning systems also use these lines to supply refrigerant gas from the evaporator to the compressor. Most refrigeration systems circulate a mixture of liquid or gas refrigerant and a liquid lubricating oil to the compressor. Reciprocating compressors can be damaged by excess liquid flowing back down the line, so an accumulator is usually added to hold the liquid and provide a more constant liquid flow.