Spare rotors, testing

The main plant s manufaeturing faeility was also responsible for produeing the new diffuser and first- and seeond-stage stator assemblies, in addition to many other miseellaneous parts. The owner/user s spare rotor was used as part of the rebuild. Complete disassembly, dimensional, and penetrant inspeetions of the rotor were eondueted. New blades were installed in the dises. Final qualifieations of the rotor ineluded rotor stud streteh tests, balaneing, and meehanieal and elee-trieal runout eheeks. 

If there is a spare rotor sold with the order, the spare rotor is also heat cycled. If the customer requests, it too can be mechanically tested prior to shipment. If a motor drive is required, the initial run-up is... 

Cleanliness Hardness Hydrostatic Tests Blade Shaker (Static) Rotor balance O Standard O High Speed Final Surface Inspection Crating inspection Spare Rotor Fit ... 

Spare rotors are frequently part of a new compressor contract. A deci sion must be made regarding the testing of the spare rotor. The recommended practice is to mechanically run spare rotors, using the same procedures used for the main. As a matter of logistics, the compressor is usually shipped with the last run rotor. If a performance test has been specified, it can be run before the rotors are changed and both rotors performance tested. This would not be economical, however. 

As an alternative, used when the cost of the extra running does not warrant mechanical testing of both rotors, the spare rotor can be fitted to the case and only clearance measurements taken. This is philosophically similar to the reciprocating compressor bar over test. 

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