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1.3.1 C1) Complete unit test in closed estimated in the operating conditions of the project.
loop
It is called Type 1 in accordance with ASME PTC
10, Chapter 3.2 - Types of Tests.
It is performed using test gas, available at factory.
Test gas
It is mainly methane plus some additives, dosed in
such a way to reproduce the same density of the
process gas. Slight deviations on the gas density
are allowed, within specified limits.
The test is performed at full pressure, full-speed,
full load, full density. The train operating parameters
are recorded, both at guarantee point, both at
other operating points.
The Complete unit test Type 1 appears to be the
most complete test.
At the end of the test there is a technical meeting
between the Manufacturer and the Customer’s
representative to discuss the acceptability of the
recorded results.
If the test is evaluated acceptable, the train is then
removed, the various components separately
packed and prepared for shipment to the field.
1.3.2 C2) Complete unit test in closed
loop similarity
It’s called Type 2 according to ASME PTC 10,
Chapter 3.2 - Types of Tests.
Test gas has lower density (lean gas). This allows
lower power consumption and lower heat to
dissipate in the cooler.
The test is performed at lower speeds, pressures,
flow rates, power, in terms of similarity. Appropriate
calculations allow to go back to the values
Fig. 3 - Test bed
42 Impiantistica Italiana - Luglio-Agosto 2015
We call:
• rPHQassstpppecccdttthhhpeeeossinppctee)a;cclciiffuiieeladdtehfldoewapd(oa(watttehtrheedrareatmetedadnpdpooini(nat)tt;); the
•
•
• Qtest the flow rate in the test;
• Htest the head measured in the test;
• Ptest the power measured in the test.
The relationship for the power is the following:
Pspc = Ptest (Qspc Hspc) / (Qtest Htest)
WeqhuearletoPsoprc,lothweermtheaansutrheed power value, must be
value resulting from the
calculation. tIhf ethpeoPwsepcr is lower than the predicted
one, since consumption is lower than
expected, the performance is greater.
1.3.3 C3) No load Complete unit test
The test is carried out on the complete train, with
no load. No test gas is used. Mainly the vibration
levels and functionality of the auxiliaries are tested.
Test bed (figure 3)
For the execution of the Performance Test the
Manufacturer is equipped with a “closed loop”
(figure 4), which collects the test gas from the
compressor outlet and send it back to the inlet,
after cooling and depressurization.
The system is mainly composed of:
• manifold;
• pressure reducer valve;
• heat exchanger;
• piping;
instrumentation.