Design and Development of Fixtures used for the Production of Circuit Breaker Components

Abstract

MCCB (Moulded case circuit breakers), ACB (Air circuit breakers) are an automatically operated electrical switch, designed to protect an electrical circuit from damage causes by excess current, typically resulting from an overload or short circuit. Its basic function is to interrupt current flow after a fault is detected. In any power system, Circuit breaker is used to operate any electrical equipment in, on load condition as well as in case of severe short circuit faults, which require handling of large mechanical stresses. The use of fixture has become very essential in manufacturing industries; it can achieve higher accuracy and production rate with good quality. The repetitive and complex task can be done quite easily by the use of fixture and it also allows automation for the same. The purpose of this project is to develop fixtures for the various shops and implement the POKA-YOKE in the fixture in order to save the rejection, cost and reduce cycle time for the finish components. The PFMEA (Potential Failure Mode and Effect Analysis) is done on the design of the fixture so that after the implementation there are no further correction required in the fixture, thus saving the machining cost as well as the material cost required to manufacture the fixtures. The fixtures for the brazing shop are designed in order to control the rejection occurring due to no availability of the fixture and obtain the control over the process for brazing of the components. The fixtures for the CNC designed in order to accommodate the operation by replacing the tool in return which also reduces the cycle of the finish component. Various schemes are conceptualized based on parameters such as, fixture assembly planning, handling ease, machine travel distance, fixture weight, etc. The fixtures are modelled using CAD software like Pro-E/Creo. By carrying out the PFMEA on the fixtures, the best possible design is selected.