1.1.5 Mechanical Joint: Press Fit

Press fits, or interference fits, involve an inner component, such as a shaft, forced into an undersized hole. Once assembled, the parts are held together by the friction of the press fit. Press fits require machining to tight tolerances and precise, accurate placement at high force, typically with a hydraulic press.

1.1.6 Mechanical Joint: Shrink Fit

A shrink-fit joint is an extreme form of an interference fit. The negative clearance is larger than that of a standard press fit, with the outer diameter of the inner element being significantly larger than the inner diameter of the component or sleeve into which it is pressed. To achieve this assembly, the outer sleeve is heated before the inner component is forced into it. Because the outer element will cool very rapidly and the inner element will heat up, the assembly must be completed quickly as it will not be adjustable once it has cooled. In addition, the outer component will be under high stress and may be designed to be larger and heavier to compensate.

Press-fit joints and shrink-fit joints can cause high stresses that lead to the destruction of the assembly (Figure 12), especially during the operating time when the hub has a load caused by a torsional moment.

Figure 11 Press fit tolerances are designed with negative clearance while still allowing room-temperature assembly
Figure 12 Excessive press fit or shrink fit stress may contribute to failure during assembly or disassembly, or even during operation, if combined stresses are too high

Table of contents

Already have an account? Sign in

+33,000
professionals

have already
signed up

Award winning manual

Platinum Award for LOCTITE®X Digital Manual

The Digital Manual is for professionals by professionals

The manual is made entirely for you. However, if you’re still not convinced that free industry knowledge is for you, take a look at these user testimonials from the users of the manual.

"The topics are such that I can help take design related decisions very well at work. It's an interesting and knowledgeable read, I recommended my other colleagues to have a look at the manual as well."

Hanumant, Production Incharge

"The manual's chapters significantly enhanced my comprehension of various engineering topics. The manual adeptly presents explanations and examples of concepts, showcasing a high level of clarity and effectiveness in its content."

Tejas, Mechanical Engineer from a renowned Engineering College

"The release of this manual by a renowned brand such as Loctite has proven to be highly motivating for students. Its authentic content serves as a source of inspiration, encouraging students to engage actively in reading and learning."

Padmakar Deshmukh, Professor at an Engineering College