PDA

View Full Version : Pump down ,vibration and VFD



civic9696
22-07-2010, 05:53 PM
Guys


Please see below recommendation from Vendor on our facility. Please advise if you have any comment or feasible suggestion for improvement.Many Thanks



1. HVAC Compressor - Vibration dampening.
a. Impact: When HVAC compressor is in operation there is excessive noise heard in the mess room due to vibration of the compressor. Prolonged running in such condition may cause ………….
b. Proposed Solution: To install a vibration dampener.
i. To mount the compressor unit and associated components on a 25mm plate.
ii. To install at least six (6) vibration dampeners under this plate.
iii. To commission back the compressor after the modification and monitor performance.

2. HVAC Compressor - VFD.
a. Current Impact: The compressor for the HVAC system is overcapacity. In order to co
b. Proposed Solution: To install a variable frequency drive (VFD) to control and the running speed of the compressor so that speed can be reduced gradually when the cooling has been achieved.
i. To install a VFD

3. Pump-down system.
a. Impact: Whenever any maintenance is needed to be done onboard on the HVAC Systems such as replacement of parts, gases are released and these are not recoverable. New gases bottles are used to replenish.
b. Proposed Solution: To have in place a portable pump down system to recover the gas from a particular cooling system when maintenance work is carried out on that system.
i. To design, fabricate and assemble a portable temporary recovery system that meets EU standards for pressurized vessel.

RANGER1
22-07-2010, 08:59 PM
All sounds good but what is the cause of vibration and has it always been there ?
What type of compressor is it & how is it driven ie belts or direct drive .
If its a screw I would first check its condition and history .
Coupling alignment & coupling should be first port of call to check recip or screw .

VFD can also cause vibration under certain conditions & sometimes under these conditions this frequency is skipped using PLC control etc .

civic9696
23-07-2010, 12:41 PM
Dear RANGER1

Thank you for kind respond.
Maker:CARRIER
Model:3GAGNH44 - HLA4IL17

It is driven by direct coupling. I believe this screw compressor. i will check for alignment again

civic9696
23-07-2010, 12:44 PM
All sounds good but what is the cause of vibration and has it always been there ?
What type of compressor is it & how is it driven ie belts or direct drive .
If its a screw I would first check its condition and history .
Coupling alignment & coupling should be first port of call to check recip or screw .

VFD can also cause vibration under certain conditions & sometimes under these conditions this frequency is skipped using PLC control etc .


Dear RANGER1
Maker:CARRIER
Model:3GAGNH44 - HLA4IL17

i belive this is screw compressor and driven by direct coupling.Will check the alignment again

thank you for kind comment

NoNickName
23-07-2010, 01:09 PM
1) overhaul the compressor
2) buy a smaller compressor
3) release of gas in the atmosphere is forbidden by a number of regulations. Recover and condense the refrigerant into portable cylinders.