What is a pump Spillback?
A spill back line is generally given to maintain suction pressure or suction head of a pump or any other device. In it a line or tapping from the downstream of pump is given to the upstream of pump so that some of the discharge flow of pump can be brought to the suction until required pressure is obtained.
What is stepless control?
Stepless capacity control is an efficient, dynamic and fully automated control system. Only the required amount of gas needed is being compressed, unlike other control systems like bypass valves that recirculate compressed gas, or stepped control that compresses more gas than needed.
What is spill back in compressor?
‘Spill back’ on reciprocating compressors is one method of controlling the capacity of the compressor. Other methods include variable speed, clearance pockets, and suction throttling. Browse our refining and petrochemical technology Q&A.
What is compressor capacity control?
Compressor capacity-control methods are utilized to maintain a required compressed gas delivery under variable process conditions. The main capacity control methods for reciprocating compressors are variable-speed drives, suction valve unloaders, step-less methods, clearance pockets and bypass recycling.
What is the purpose of minimum flow?
The purpose of minimum flow is generally to prevent undue wear and tear or damage to the pump. In the real environment of a process or utility plant, a pump is operated at just about any condition demanded by the situation at hand. Thus there are different pump minimum flows for different purposes.
Why is pump recirculation required?
Automatic recirculation valves, sometimes referred to as pump protection valves or minimum flow valves are installed on the outlet of a centrifugal pump discharge line. Their purpose is to prevent the pump from overheating by ensuring that there is a minimum flow through the pump at all times.
What is stepless speed?
Stepless speed control, with the ability to adjust the speed of the fan. Stepless speed controller can be widely used in various dc brushed motors. The motor speed controller is used to adjust fan speed.
What is capacity control?
What is Capacity Control? Capacity control of a refrigeration plant can be defined as a system which monitors and controls the output of the plant as per the load on demand. As the load (temperature) of one room is reached to its required temperature, there will be no more need of the refrigerant for cooling.
What is unloader function in reciprocating compressor?
How Does an Unloader Valve Work? When the air pressure inside the compressor’s tank reaches the pressure switch’s cut out pressure (the point when air is no longer delivered), the switch automatically trips off and interrupts the power supply to the motor.
What is suction valve in compressor?
The suction valves permit flow into the cylinder but not back out, and discharge valves permit flow to exit the cylinder but not return back in. Suction and discharge valve failures are the most common component failure in a reciprocating compressor. Unloaders may be part of the suction valve assembly.
How does a minimum flow valve work?
A minimum flow aids the cooling of the bearings and the seals within the pump and reduces the potential for a continuous stop/start situation. The valve maintains a minimum flow through the pump, whilst also acting as a non- return check valve for the pump.
What is Mcsf in pump?
The minimum flow quoted for continuous operation is usually referred to as minimum continuous stable flow, or its more common abbreviation, MCSF. A pump’s MCSF is the flow below which the pump should not be operated continuously. The primary purpose of MCSF is to achieve satisfactory bearing and seal life.
What are the advantages of stepless drive?
MINIMIZED LOAD SWING. EXCELLENT LOAD HANDLING CAPABILITIES. NO CRANE SKEW. OPTIMISED LOAD CURRENT DEPENDING ON THE LOAD BEING HANDLED.
Which of the following method can be used for stepless speed control of induction motor?
Right Answer is: B pole amplitude modulation.
What is the purpose of an unloading valve?
Unloading valves are typically used in high-low circuits. The circuit is sometimes referred to as a fast approach, slow feed circuit. The unloading valve is put to good use in a system where a high flow volume is needed at a lower pressure, and then later a low flow volume is required with a higher pressure.