AUTOMATION TO BOOST PRODUCTIVITY AT RAILWAYS

Case study of  Universal Shell Body  Assembly  station

Industrial machines (IM) – a line of business of Godrej Tooling, provides specialized solutions including automation of jigs & fixtures, material handling, welding, and robotics for a wide range of manufacturing activities for improving productivity in Indian Railways and metro rail sectors. All along, IM has met the requirements of various businesses of Godrej & Boyce Mfg. Co.Ltd. It is in the last 3 to 4 years, that IM has forayed into catering to the requirements of automation from a select group of customers in  Indian Railways (IR)and ordnance factories (OFs). Over the years, IM has acquired substantial, varied experience for taking on large and technically complex assignments.

Currently, Indian Railways is facing the challenge of increasing productivity substantially in their production shops to meet the growing demands of passenger and freight traffic.   In  2019, the Executive Director of Rail Vikas Nigam Ltd(RVNL), invited Godrej Tooling to conceptualize and develop an indigenous solution for coach Assembly fabrication with Universal Shell Body  Assembly Fixture (Qty being  2 sets)  for their upcoming   Rail Coach Factory at Latur.

In response, the IM design team carried out extensive studies of current manufacturing processes which included in-depth interactions with the factory personnel at Integrated Coach Factory (ICF) Chennai to arrive at designing a flexible Jig fitted with automated welding arrangement which can accommodate multiple coach variants.

Previously Coach Shell Bodies were assembled and welded on a conventional type of fixture having all manual operations. This required lot of human efforts for clamping, alignment, and welding. The time required for all these activities was high (more than 2 shifts) for each coach. Further different variants of coaches require a separate set of fixtures consuming a lot of floor space and capital investment. Considering the growing requirements of Railways, Godrej Tooling  Designed  &  developed a Universal Coach Assembly station with an Auto welder setup. This  Integration STATION  is capable of welding different variants of coaches like EMU, MEMU, and LHB type coaches through flexibility in Clamping, resting level pads, and slides.

Each Coach consists of components like underframe, sidewalls, end walls, and Roof which are assembled, rigidly secured, and clamped in the state-of-the-art Universal Assembly station and then sequentially welded through a set of auto welders for seamless welding. This minimizes human efforts, improves the welding quality, and also reduces cycle time.

The manufacturing process involves underframe being placed on trestles in the previous station, various brackets for underslung components are welded and couplers are fitted.

The complete underframe is then lowered on dummy trollies which transfers the component into the shell assembly station. In this station, the underframe is lifted, leveled, aligned, and clamped in the required position. Shell parts such as Roof, End walls, side walls are loaded on the underframe and clamped automatically in a position to ensure squareness and defect-free welding.

The latest generation of metal and tungsten inert gas welding is employed in auto mode using auto welder cum oscillators powered by synergic pulse welding sources. Magnetic Flexi tracks are used for welding Doors and end walls. Once the welding is completed The Shell Body is de-clamped, lowered on dummy trollies, and transferred to washing and painting stations for carrying out further activities.

In spite of adverse conditions, the IM Team successfully installed and commissioned both the Assembly stations at Rail Coach Factory Latur in Dec 2020  by carrying out trial production and rolled out the first MEMU coach shell much to the delight of customer-RVNL. This emphasized Godrej’s contribution towards Make in India and Aatma Nirbhar Bharat.

 Many benefits are accrued to IR, the major being, deskilling of operations, enhanced production, and a huge increase of 100% in the productivity of the line.