The Press Fitting System In Engineering
Press fitting is the fastening of two parts through friction. This type of bond is usually done for metals wherein one part is bigger than the other. This fitting system is also called interference fit because one of the elements interferes with the space of the other element. A press fitting system is often used to bind the two parts through compression. The press fit is often used to connect shafts and bearings, pipe fittings and cables.
Comparing the shrink fitting system and the press fitting system
In shrink fitting, thermal energy created a hole in one metal and another piece is forced through it by pressure. When the heated metal cools down, the hole tightens and a strong bond is created. Though shrink fitting requires less force, high amounts of thermal energy are needed to pull it off. Induction can also be used if two metals are to be fused together.
Meanwhile, press fitting does not require thermal energy but the press fitting system that will be used must generate high pressure levels. The bond created using press fitting is weaker compared to the bond via shrink fitting. Also, press fitting is not advised if one element has a tendency to buckle.
Creating a fit with a press fitting system
Due to the created pressure by the fitting system, the fused elements tend to be deformed but the bond between the two parts is tighter. Torque can be applied on the conjoined parts to test whether the press fit is a success. If the bond created through a press fit is tight, the two parts must move as one.
Most systems for press fitting are equipped with hydraulics and they are used for industrial purposes. However, there are hand presses that can get smaller jobs done. Hydraulic fitting systems can produce more force to create tighter bonds for bigger and tougher materials.
Before the press fit is executed, calculations are done to determine the right amount of force needed to get the best fit without exposing the parts to breakdowns. Online press fit calculators can be used to make the calculations faster and easier.