Compressors suction

Gas compressor steam cleaning facility with steam injection in the compressor suction main and in the discharge-side labyrinth shaft seal... 

The expander-compressor will attain a speed of 5,000-15,000 rpm, depending on the design horsepower of the machine. If the design pressure of the compressor suction is higher than the design pressure of the expander discharge (pre-boost type), increase the speed to approximately 80% of the design speed as rapidly as possible. This... 

In this automatic thrust balancing system, the pressure behind the compressor wheel is controlled to a value between the compressor suction pressure and the wheel peripheral pressure. As the expander inlet pressure increases above the compressor suction pressure level, the resulting thrust force pushes the compressor wheel, and hence the rotor system, towards the compressor suction. In the reverse situation, when the pressure behind the compressor wheel is reduced below the wheel peripheral pressure level, the rotor system moves toward the expander. 

The correct flow to use is the compressor suction. However, a flow element such as an orifice in the compressor suction can rob inordinate horsepower. Therefore, sometimes the discharge flow is measured and the suction flow computed within the controller by using pressure measurements. Other times the compressor intake nozzle is calibrated and used as a flow element. The correct AP to use is the discharge minus the suction pressure. 

On-off two-position with differential gap Slow Any Any Large-capacity temperature and level installations. Storage tanks, hot-water supply tanks, room heating, compressor suction scmbber... 

It has played a dual role, one in Equation 2.18 on specific heat ratio and the other as an isentropic exponent in Equation 2.53. In the previous calculation of the speed of sound. Equation 2.32, the k assumes the singular specific heat ratio value, such as at compressor suction conditions. When a non-perfect gas is being compressed from point 1 to point 2, as in the head Equation 2.66, k at 2 will not necessarily be the same as k at 1. Fortunately, in many practical conditions, the k doesn t change very... 

A PR valve is not required for protection against fire on any vessel which normally contains little or no liquid, since failure of the shell from overheating would occur even if a PR valve where provided. Examples are fuel gas knockout drums and compressor suction knockout drums. (Note Some local codes require pressure relief valve protection for "dry drum" situations.)... 

Liquid loads are considered from all safety valves that discharge as a result of a single contingency, plus in each case an allowance for knockout drum liquids (fuel gas knockout drums, absorber overhead knockout drums, and compressor suction and interstage knockout drums) equal to the inventory of all drums which discharge to the blowdown drum, at their LHA point. 

Flare - Vapor streams, such as compressor suction diversion on catalytic cracking and steam cracking units, are normally routed to a flare. 

Withdrawal of vapor at maximum compressor suction rate. 

Work of Compression. This is the enthalpy of a lb of refrigerant at compressor discharge conditions minus the enthalpy of a lb of refrigerant at compressor suction conditions. 

Compressor suction 13.8 psig (28.5 psia). This allows an assumed (must be checked) pressure of 10 psi in the piping from the evaporator to the compressor suction flange. This should be a conservative drop and should... 

This volume, 4,600 scfm (14.7 psia and 32°F), is dry and must be increased by the water vapor that will accompany it into the compressor suction. ... 

Compressor Suction and Discharge Drums Design Method—Acoustic Low Pass Filters... 

Design suction and discharge bottles for an ethylene compressor. Suction drum is to be sized for an orifice meter a short distance upstream. Discharge drum is to be sized for prevention of piping vibration. 

The FCC reactor pressure is usually controlled at the suction of the wet gas compressor. The reactor pressure is the wet gas compressor suction pressure plus pressure drop through the main fractionator system. 

A portion of liquid from the overhead receiver is refluxed back to the tower and the remainder is pumped on to the gas plant. The vapor from the receiver goes to the wet gas compressor. The pressure of the reactor/main fractionator system is usually controlled at the compressor suction. 

Dynamic compressors impart energy to the gas by velocity or centrifugal force and then convert this to pressure energy. The most common type is the centrifugal compressor. Suction gas enters axiallyinto the eye of a rotor which has curved blades, and is thrown out tangentially from the blade circumference. 

Evaporators which keep the oil moving by means of continuous fluid velocity, until it gets back to the compressor suction, are termed dry expansion. In these, the refrigerant is totally evaporated. 

Should a float control fail, the level in the shell may rise and liquid pass into the compressor suction. To warn of this, a second float switch is usually fitted at a higher level, to operate an alarm and cut-out. 

Back pressure regulation valves (Figure 9.5) can be used in the suction line, and their function is to prevent the evaporator pressure falling below a predetermined or controlled value, although the compressor suction pressure may be lower. 

Piping circuits will usually contain a small quantity of dirt, scale and swarf, no matter what care is taken to keep these out. A strainer is fitted in the compressor suction to trap such particles before they can enter the machine. Such strainers are of metal mesh and will be located where they can be removed for cleaning. In some configurations two strainers may be fitted. 

Pressure drops on the high-pressure side will be small enough to have little effect on the performance of the complete system. Pressure losses in the suction pipe and its fittings, especially if this is long, should be checked, and a correction made for the actual compressor suction pressure. For low-temperature applications, pipe sizes may have to be increased to avoid excessive frictional losses at these low pressures. 

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