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Heating a stainless steel sleeve for industrial washers
Shrinkfitting a steel mud pump liner
Shrink fit a steel gear onto a steel gear motor shaft
Shrink fitting a carbide ring into a valve seat
Shrink fitting auto turbo charger impeller blades onto an aluminum shaft
Shrink fitting aluminum pulley to insert inner bearing
Shrink fitting an assembled wrist pin into a connecting rod
Shrink fitting a cast iron rocker arm assemblies
Shrink fit a motor shaft and roller
Shrink fitting a Camshaft Gear
Shrink fitting a Fuel Pump Housing and Inserts
Shrink fit a carbon graphite ring insert into an outer steel band
- Background
- Using Induction
- Electric Motors
- Couplings and Gears
- Valve Stems
- Solutions
Shrink fitting is a procedure in which heat is used to produce a very strong joint between two pieces of metal, one of which is inserted into the other. Heating causes one piece of metal to contract or expand on to the other, producing interference and pressure which holds the two pieces together mechanically.
Most applications involve a shaft with a given outside diameter and another part such as a gear, steering knuckle or washer which has a bore hole. There are several forms of this type of joint, characterized by the amount of tolerance (space) between the two parts. The shrink fitting process is used for the interference fit type joint.
By heating the mass around a bore hole uniformly, it is possible to significantly expand the size of the hole. The shaft is then easily inserted into the expanded hole. Upon cooling, the mass around the hole shrinks back to its original size and frictional forces create a highly effective joint.
Induction heating systems provide the speed, accuracy and repeatability necessary to produce quality shrink-fitted joints. With a properly designed work coil, induction heating can uniformly heat the bore hole, producing repeatable expansion. With the remote heat station capability of induction heating systems, shrink fitting can be done on the production line.
Typical RF power supplies for metal to shrink fitting range from 5 to 100kW, depending on the parts and application requirements.
Fitting Rotors to Shafts
This machine has been developed for heating the rotors of electric motors. Rotors and motor shafts are manually placed and when the door is closed, the heating and fitting cycle are carried out automatically. Automatic loading/unloading systems can be supplied.
Fitting Couplings and Gears to Drive Shafts
This induction heater was purpose built for use in an electric power generation station. The equipment is totally self- contained and has a built in cooling system and as such, only requires a three phase mains supply. The application required the use of a flexible water cooled work coil that could easily be wound around a large diameter coupling for heat shrink fitting and removal.
Fitting of Valve Stems into Cylinder Heads
This machine is used for heating aluminium cylinder heads in the automotive industry. Once the cylinders head has reached the required temperature it is removed from the induction heating coil and the valve guide stems are fitted.
Allow a long soak time for the metal housing to ensure that the whole mass has reached uniform temperature and expanded.
Employ an alignment fixture to smoothly guide the shaft into the housing.