Why are tolerances important in engineering?

Tolerances are crucial in engineering because they determine the permissible variation in the dimensions of a part, which ensures that components fit together precisely during assembly. When parts are manufactured, small variations can occur due to machine limitations, human error, and other factors. By specifying tolerances, engineers can guarantee that despite these variations, the parts will still interact as intended, allowing for proper function and reliability of the final product. This is especially important in mechanical systems where the precise alignment and functionality of components are essential for the overall performance and safety of the system. Without adequate tolerances, parts may fit poorly, leading to malfunctions or increased wear and tear. Thus, they play a vital role in quality control and the overall effectiveness of assembly processes.