tailieunhanh - Root Cause Failure Analysis Episode 10

Tham khảo tài liệu 'root cause failure analysis episode 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 262 Root Cause Failure Analysis pressure will be transmitted to any piping or machine connected to the discharge piping and located within 28 ft of the compressor. Note that for a single-acting cylinder the wavelength will be twice as long. Imbalance Compressor inertial forces may have two effects on the operating dynamics of a reciprocating compressor affecting its balance characteristics. The first is a force in the direction of the piston movement which is displayed as impacts in a vibration profile as the piston reaches top and bottom dead-center of its stroke. The second effect is a couple or moment caused by an offset between the axes of two or more pistons on a common crankshaft. The inteưelationship and magnitude of these two effects depend on such factors as number of cranks longitudinal and angular arrangement cylinder arrangement and amount of counterbalancing possible. Two significant vibration periods result the primary at the compressor s rotation speed X and the secondary at 2X. Although the forces developed are sinusoidal only the maximum . the amplitude is considered in the analysis. Figure 22-1 shows relative values of the inertial forces for various compressor arrangements. Compressors 263 CRANK ARRANGEMENTS FORCES COUPLES PM4ARY DQMMM PRIMARY SXMMRY SHGLE CRANK F WIWUT COUNWMfTB. COUNTÔỈm. F NONE N0NỊ TWO CRANKS AT ISO IN LINE CYLINDERS OPPOSED CAJMERS E Cj3-S3 zoo ZERO 200 it WITHOUT COUNWWVTE MTDttm. NIL NONE NIL TWO CRANKS ATM 141F WITHOUT COUNTERWn. F wrrw COUNTERWTE ZERO rorFb WITHOUT OOUWT1NWTS. OAMFb WITH CCUNTOWTE. rt TWO CYLINDERS ON ONE CRANK CYLINDERS AT 90 F WITHOUT OOUNTIMVTt low WITH OOUMTtNWTK 141F NIL NIL TWO CYLINDERS ON ONE CRANK OPPOSED CYLINDERS - 32 tf wrrHOOT eowniDMnv Fwtth cauMTiMm. ZERO NOW NIL THREE CRANKS AT 120 ZERO ZERO MF wrTHOUT COUNTTMm I7SF WITH OOUNTERWT1. 14 rt FOUR CYLINDERS CRANKS AT ISO Ị -H-J CRAM S AT 90 ZERO ZERO 4F ZERO ZERO i44FbvmN0UT COUNTENNTS WOT Ft WITH COUNWWTE. ZERO 40rt J SIX CYUNOERS .