Piping Forces And Moments On Compressors And Steam Turbines.
Abstract
At recent chemical plants and liquefied natural gas (LNG) plants, the increase of plant capacity has caused the size of turbomachinery to increase and larger nozzle sizes are being utilized. Especially for offshore facilities, a simpler piping arrangements is required despite the larger capacity trend because the space around the turbomachinery is constrained and therefore the piping design allows for less flexibility in its arrangement. Additionally, the heavier total weight of the turbomachinery and the larger size of piping nozzles make it more difficult for plant contractors to handle external piping forces and moments. Although NEMA SM 23 (1994) or API standard 617 (2002) have been conventionally referred to for allowable loads in turbomachinery piping arrangement designs, the increase in plant capacity and piping size with larger machine installations for offshore facilities has heightened the need to relax this specification. In this study, the possibility of relaxing the maximum allowable load on centrifugal compressors and steam turbines in investigated based on the general design philosophy of turbomachinery, the authors’ experience and analysis of quantitative influence using finite element method (FEM) of typical machines with a piping load of 1.85 times the allowable limit specified by NEMS SM 23 (1994). Various key components including nozzle deformation, stress level, clearance and misalignment of shaft ends a reexamined and, as a result, a bottleneck (i.e., the limiting factor) which should be taken into account for centrifugal compressors and steam turbines, is clarified in the case of excess piping load. Finally, applicable solution from the machine manufacturer’s side are suggested in order to relax this specification for piping loads on turbomachinery.
Description
Special Paperpg. 267-274
Subject
TurbomachinesCollections
Citation
Yagi, Katsuki; Higashio, Atsushi; Kawashima, Hirokazu (2009). Piping Forces And Moments On Compressors And Steam Turbines.. Texas A&M University. Turbomachinery Laboratories. Available electronically from https : / /hdl .handle .net /1969 .1 /163098.