Tham khảo tài liệu 'arnold, k. (1999). design of gas-handling systems and facilities (2nd ed.) episode 2 part 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Reciprocating Conipre VA rs 311 Single-acting cylinder crank end RLC ap pu - ps ar ps I1-I2a RL -ap Pd-Pu -arPd ll-12b Double-acting cylinder RLe ap Pd-Ps arPs 11-13 RLt ap Pd-Ps -arPd 11-14 where RLC rod load in compression lb RLt rod load in tension lb ap cross-sectional area of piston Pd discharge pressure psia Ps suction pressure psia pu pressure in unloaded area psia ar cross-sectional area of rod The calculations shown above provide the gas load imposed on the rod and crosshead bushing by the compressor cylinder piston. To provide a reasonable crosshead pin bushing life the rod loading at the crosshead bushing must change from compression to tension during each revolution. This is commonly referred to as rod reversal and allows oil to lubricate and cool one side of the bushing while load is being applied to the other side of the bushing. A single-acting head end cylinder will not have load reversal if suction pressure is applied to the crank end. Similarly if discharge pressure is applied to the head end of a single-acting crank end cylinder load reversal will not occur. In addition to the gas load the rod and crosshead pin bushing is subject to the inertia forces created by the acceleration and deceleration of the compressor reciprocating mass. The inertia load is a direct function of crank radius the reciprocating weight and speed squared. The total load imposed on the crosshead pin and bushing is the sum of the gas load and the inertia load and is referred to as the combined rod load. The combined rod load should be checked anytime the gas loads are approaching the maximum rating of the compressor frame or anytime rod reversal is marginal or questionable. 312 Design of Gas-Handling Systems and Facilit ies COOLING AND LUBRICATION SYSTEMS Compressor Cylinder Cooling Traditional compressor cylinder designs require cooling water jackets to promote uniform distribution of heat created by gas compression and friction. Some of the perceived advantages .
