Mechanical Seals for Zero Leakage

Written by Thomas Yoon

A centrifugal water pump contains a few basic components as follows:

1) The housing for containingrepparttar water. 2) The impeller attached to a rotating shaft that movesrepparttar 133423 water. 3) The coupling that transmitsrepparttar 133424 rotating action of a motor (or other prime movers) torepparttar 133425 pump shaft. 4) The seal betweenrepparttar 133426 housing andrepparttar 133427 rotating shaft. 5) The bearings for ensuring thatrepparttar 133428 shaft turns smoothly. 6) The inlet andrepparttar 133429 outlet ports for channelingrepparttar 133430 water flow throughrepparttar 133431 pump.

In order for a pump to work,repparttar 133432 pump impeller must generate pressures insiderepparttar 133433 pump housing. The seal betweenrepparttar 133434 housing andrepparttar 133435 rotating shaft plays a critical role in makingrepparttar 133436 pump work.

One ofrepparttar 133437 most common ways of sealing a rotating pump shaft is by using mechanical seals.

The 3 components of a mechanical seal are: 1) The rotating component that moves together withrepparttar 133438 rotating shaft. 2) The stationary component that is fixed torepparttar 133439 pump housing. 3) The spring that pressesrepparttar 133440 rotating component ontorepparttar 133441 stationary component axially.

Rotating Component

This is a ring, usually consisting of 2 types of materials - a soft carbon piece with a highly polished axial surface, and a rubber material or o-ring that is able to griprepparttar 133442 shaft for sealing against water leak throughrepparttar 133443 shaft surface.

Simple But Powerful Centrifugal Chillers

Written by Thomas Yoon

Centrifugal chillers are used for cooling large buildings in a centralized air conditioning system. There are other types of chillers using screw compressors and reciprocating compressors. These are usually smaller in size. Today's topic is about centrifugal chillers -repparttar ultimate choice for any air conditioning installations higher than 500 RT (refrigeration tons)

Basically, centrifugal chillers use centrifugal fans to move repparttar 133422 refrigerant withinrepparttar 133423 chiller circuit. As with any refrigeration circuit, there must be a compressor, a condenser, an expansion device, andrepparttar 133424 evaporator.

Inrepparttar 133425 case ofrepparttar 133426 centrifugal chiller,repparttar 133427 fan isrepparttar 133428 compressor. Rotating at very high speeds, it is capable of pressurizingrepparttar 133429 refrigerant gas so as to increase its temperature. Becauserepparttar 133430 pressure is so dependent onrepparttar 133431 efficiency ofrepparttar 133432 impeller ofrepparttar 133433 compressor,repparttar 133434 impeller is very carefully designed to matchrepparttar 133435 system.

The clearances betweenrepparttar 133436 impeller andrepparttar 133437 housing atrepparttar 133438 mouth ring (impeller suction) are made very small so as to reduce leaks back torepparttar 133439 discharge.

Usually inlet vanes that throttlerepparttar 133440 gas controlrepparttar 133441 flow ofrepparttar 133442 gas, and thusrepparttar 133443 chiller load. The expansion of repparttar 133444 liquid to gas is usually made through a fixed orifice.

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