Jaw Crusher Pitman
Pitman” means “connecting rod”, but in a jaw crusher it doesn’t connect two things. The pitman refers to the moving jaw in a jaw crusher. It achieves the reciprocating movement through the eccentric motion of the flywheel shaft. This creates enormous force in each stroke. Jaw crusher Pitman is fabricated from high quality steel plates and stresses are removed after welding. The Pitman is fitted with two replaceable high strength steel Alloy or manganese steel toggle bar. Grooves housings for the bearings are accurately bored and faced to gauge.
As an interesting aside the term “pitman” means “connecting rod”, but in a jaw crusher it really doesn’t perform this function, that is it doesn’t connect two things. Other mechanisms called pitmans such as linkages in car/truck steering systems actually do connect things. Thus it appears this is just the name that was applied to this part.
The jaw crusher pitman is covered on the inward facing side with dies made of manganese, an extremely hard metal. These dies often have scalloped faces. The dies are usually symmetrical top to bottom and can be flipped over that way. This is handy as most wear occurs at the bottom (closed side) of the jaw and flipping them over provides another equal period of use before they must be replaced.