Connecting Rod

Link which connects a revolving crank pin to a reciprocating cro -head or an oscillating beam in an engine. The crank end will always have a single eye, but the other end may be forked to have a double bearing. This is to be avoided when po ible, as it is difficult to make the rod swing true. To enable wear to be taken up easily at the pins, each end of the rod has a STUB-END (q.v.) with bra es. When a connecting-rod comes from a beam to a shaft or other working piece, it has been called a pitman, since in the earlier beam engines for mine pumps this connecting rod pa ed down into the mine pit. Newer connecting rods are made of steel. In locomotives the connecting is often called the main rod, to distinguish it from the side or parallel rods, which couple the driving wheels together.