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1- visible package checking for damage or lost.
2-survey report & drawing checking.
3-bace plate and foundation ,bolts,oriantation,normal checking.
4-read instruction manual and drawing approved by vendor, for installation & commissioning.
5-unpacking and checked by vendor list .
6-have a lifting plan approved by HSE/QC and vendor.
7-utillity and requirement should be ready such as ,water , fresh air, drain, etc...
step by step checked vendor manual for commissioning, all procduer should approved by owner , QC,vendor.
Every centrifugal compressor, whether it is new or has been in service for many years will most likely be tested to verify its thermodynamic performance. For a new machine the testing may be conducted in the manufacturer’s facility under strict controlled conditions or in the field at actual operating conditions. Older compressors that have been placed in service after maintenance or have been operating for an extended period of time may require testing to verify the efficiency and normal operation. This TOTM will review ASME PTC-10 (also referred to as the Code) testing procedure and other topics that contribute to an accurate centrifugal compressor test results.
This two-part series will review the salient aspects of a performance test. Part 1 will review the thermodynamic performance test objectives established in the Code as well as other factors to consider in a testing procedure. While this code is primarily applicable to shop testing it can also apply to field testing. Part 2 will review the Code assumptions and basic performance relationships. It will also examine the three important principles that influence the operating conditions and ultimately influence the accuracy of the performance test. They are volume ratio, Machine Mach Number and Machine Reynolds Number.
Introduction
The purpose of a performance test is to verify that a centrifugal compressor will perform in accordance with the manufacturer’s design at the operating conditions given in the specifications. It also provides a method of confirming the shape of the compressor head-flow curve, efficiency, and the maximum and minimum flow limits at various speeds. Frequently a performance test is conducted under field conditions with the specified gas and operating conditions. However, if the performance test is conducted in the shop it may not be possible to test the compressor with the specified gas because of safety concerns or testing facility limitations. Whether the test is conducted in the field or in the shop, proof of the compressor design is recommended and often necessary to demonstrate contractual obligations and mechanical integrity.
Frequently the gas composition used to confirm a compressor performance differs from the specified gas. This is often the case regardless if the test is conducted in the field or in the shop. For field tests, where the gas composition and operating conditions are set by the process, adjustments must be made in the calculations to confirm the compressor design specifications. Typically, a shop test is conducted with a carefully selected mixture of gases blended together to form a gas that has physical properties that closely resemble the specified gas. Even with a substitute gas, differences remain which influence the test results.
The original compressor design places limits on the thermodynamic performance. The most important of these limits include flow rate, power, temperature, pressure and speed. There are other design restraints which are not as commonly known but will also influence the compressor performance. Such factors are volume ratio, Mach number and Reynolds number. These limits were incorporated in the compressor design and are influenced by gas properties, operating conditions and the mechanical design. To verify the design and operating limits for a compressor, it is necessary to test the machine. For new machines, these tests are commonly performed in the manufacturer’s facility; however, the testing is sometimes performed in the field. It may also be helpful to periodically test a compressor to trend the machine performance. Testing conducted during commissioning will establish a baseline of performance. Periodic field tests are often conducted to verify the overall performance and signal changes that may predict mechanical damage, internal fouling, or other deteriorating conditions.
1-first of all to establish oil system .
2-start the compressor with confirming normal parameters of vibration and axial displacement .
3- keep the compressor in circulation through the anti surge valve
4- confirm the intermediate stages temperature and pressure
5- control the surge line by the anti surge and discharge.
6- maintain the suction and discharge according to the auto cascade control philosophy as applicable .
