There are many varieties of U-Joints, a few of which are extremely complex. The simplest category known as Cardan U-Joints, happen to be either block-and-pin or bearing-and-cross types.
U-joints can be found with two hub types solid and bored. Sturdy hubs don’t have a machined hole. Bored hubs possess a hole and so are named for the hole form; round, hex, or square style. Two bored designs that deviate from these common shapes are splined, that have longitudinal grooves within the bore; and keyed, that have keyways to prevent rotation of the U-joint on the matching shaft.
Using the incorrect lube can bring about burned trunnions.
Unless in any other case recommended, use a superior quality E.P. (severe pressure) grease to services most vehicular, commercial and auxiliary drive shaft applications.
Mechanically flexible U-Joints accommodate end movement simply by using a telescoping shaft (sq . shafting or splines). U-Joints function by a sliding action between two flanges that happen to be fork-formed (a yoke) and having a hole (eye) radially through the attention that is connected by a cross. They let larger angles than adaptable couplings and are being used in applications where huge misalignment should be accommodated (1 to 30 degrees).
Always make sure fresh, fresh grease is evident by all U-joint seals.
Can be caused by operating angles which are too large.
Can be caused by a bent or perhaps sprung yoke.
Overloading a drive shaft could cause yoke ears to bend. Bearings won’t roll in the bearing cap if the yoke ears are not aligned. If the bearings quit rolling, they continue to be stationary and will “beat themselves” into the surface area of the cross.
A “frozen” slip assembly won’t allow the drive shaft to lengthen or shorten. Each and every time the drive shaft tries to shorten, the strain will be transmitted in to the bearings and they will tag the cross trunnion. Unlike brinnell marks caused by torque, brinnell marks that will be caused by a frozen slip are generally evident on the front and back areas of the cross trunnion.
Improper torque upon U Joint china U-bolt nuts could cause brinelling.
Most companies publish the recommended torque for a U-bolt nut.
Improper lube procedures, where recommended purging is not accomplished, can cause a number of bearings to be starved for grease.