Rodloads, Frameloads, Flangeloads, Gasloads, Pinloads: A Discussion of the Various Allowable Loads Used to Rate Reciprocating Compressors
Reciprocating compressors are usually rated in terms of horsepower, speed and rod load. Horsepower and speed are easily understood; however, the term rod load has many different meanings to many different people. This paper will discuss the various definitions of rod load, including historical and current API definitions, manufacturers ratings, and various user interpretations. The basic kinematics of a slider-crank mechanism will be reviewed to provide a better understanding of the various definitions that are used. Analytical results and field rod load measurements will be compared to illustrate the various factors that influence rod load on typical compressor installations.