Design of Piping Loads on Rotating Machinery Nozzles
|Publication Date:||1 May 2014|
This Practice provides designers and engineers with requirements to help reduce the Total Cost of Ownership (TCO) of rotating machinery by determining allowable piping loads and piping load applications.
Owner experience has shown that designing machinery piping to the maximum published allowable loads results in low mean time between repair (MTBR) and higher than acceptable maintenance costs.
This Practice limits the application of the entire maximum allowable nozzle load during the equipment installation design, allowing some reserve margin to maximize the possibility of the final installation actually remaining within the allowable loading.
This Practice drives the stated, published and calculated allowable nozzle loads to become more performance based, tied more closely to actual effects on the MTBR and TCO for the machinery in order to:
a. Promote the highest reliability for vital or sensitive machinery and the determination of those allowable loads that will allow the achievement of that reliability
b. Allow spared (essential) machinery to be more heavily loaded, and encourage manufacturers to either furnish allowable load data or be in accordance with a published standard
c. Encourage machinery manufacturers to generate more meaningful reliability-based allowable nozzle load recommendations
d. Encourage standards organizations to look at the basis for their allowable load values/calculation methods and verify the effects on the demonstrated MTBR and Total Cost of Ownership (TCO)
This Practice describes the requirements for calculating allowable piping loads and the application of those loads for rotating machinery including pumps and compressors (centrifugal, reciprocating and rotary screw), steam and gas turbines, and liquid ring compressors. Also, this Practice may be used on fans and blowers after consultation with the manufacturer.
This Practice describes the requirements for allowable nozzle loads for vital or sensitive machinery and for essential (spared) machinery.
This Practice also outlines the requirements for minimizing loads imposed on equipment by the piping systems.