Engineering Class and Roller Chain – There is a difference
Remember the basic rule is Roller chains for power transmission and Engineering class chains for material handling. Then, remember that although both carry the same generic name, there are major differences in construction and in application. It is the knowledge of when to use either that will determine how effectively you use chain in your application.
In our reports on engineering class chain we emphasized the pin as being the “heart of the chain”. For material handling and other severe applications we advised to always select the largest pin diameter available in your pitch size. Whenever you use a roller such as in roller chains, you restrict the design possibilities especially the diameter of the pin. As the pin size increases so does the bushing and roller diameter. At a certain point the roller can become so large a sprocket tooth will not sufficiently fit in the proper space. As the pin size is restricted in roller chains so is the possible rated working load and average ultimate strength of the chain.