The Pune-based SAJ Test Plant has acquired the distinction of being the only Indian company to have manufactured a 9000 HP pressure-controlled dynamometer for a German research institute, says Huned Contractor
For a group of scientists working with the Max Planck Institute at Munich in Germany, the pressing need is to find a solution to the world's increasing demand for energy. It certainly cannot be an easy task, given the magnitude and nature of the project. But even as they go about devising ways and means of defusing the energy crisis that threatens to loom large, its research project can now boast of an Indian helping hand. That has come from the Pune-based SAJ Test Plant, a company that has been engaged for more than four decades in the production of engine, vehicle and transmission test equipments. "We were chosen to make a pressure-controlled hydraulic dynamometer of a capacity as high as 9,000 HP with torque of 50,000 Nm and speed of 2,500 RPM. No Indian manufacturer has ever made a dynamometer of this scale," informs Rujuta Jagtap, Executive Director, SAJ Test Plant.Branded the SH 6700 (F63) model, this hydraulic dynamometer, alternatively known as the water brake model, has been designed and structured to arrest a 75 MT flywheel attached to a 10 MW impulse power generator. "Such a braking system is mandatory for this kind of application since the inability of applying emergency brakes to a flywheel of such a huge dimension can result in extensive damage over a radius of up to 2 km. Therefore, this dynamometer plays a very crucial role in such an operation," Rujuta informs. This is the second 9,000 HP dynamometer built by the company in its 40 years of existence. The earlier one, built in 1993, had been supplied to the Director General Naval Project (DGNP) in Mumbai for marine engine testing applications.Elaborating on why this is indeed a unique feat, Rujuta explains that it is mainly because an order of this kind is a rare occurrence and therefore not many companies in this space would have the requisite knowledge, design, manufacturing facility or the ability to source the components from the few vendors available, if any. "Our expertise in building dynamometers comes out of our earlier joint venture with Froude Consine from 1983-1997 during which the technology was bought for manufacturing air gap eddy current dynamometers as well as pressure-controlled hydraulic dynamometers," reveals Prakash Jagtap, Chairman and Managing Director, SAJ Test Plant. The company is now 100 per cent Indian entity, and can therefore claim of complete indigenisation for the manufacturing of a wide range of dynamometers. Interestingly, the contract was awarded to SAJ from among competitors from the US, UK and Germany. "The main contractor of the project is Siemens of Germany while Piper Test & Measurement Limited of the UK has been entrusted with the design and engineering application validation for this project. We were approached by Piper around two years ago and the brief was not only to make a hydraulic braking system that would replace an existing electrical braking system but also to stop the flywheel in an emergency situation in a matter of 8 to 10 minutes. In a hydraulic dynamometer, the power is absorbed or destroyed and the heat is carried away by using water as a conveyor medium as a result of which the speed of the prime mover is immediately reduced," Rujuta explains.Now that this project has been successfully completed, SAJ is looking forward to executing more of the same. "It is not as if the demand for such high-scale dynamometers is so large as to warrant a full-time production line but we are exploring the oil drilling sector because companies engaged in drilling operations of more than 4 to 5 km below the ground will have a need for hydraulic dynamometers," states the CMD. What is also to be considered is that this kind of a dynamometer doesn't come cheap. It can cost upward of Rs 1 crore. "We have had to make huge investments in terms of enhancing our tooling, casting and other capacities to be able to make this dynamometer. This also includes providing training to our skilled workers. But now that we have the infrastructure, it will be easier to continue producing these dynamometers," Rujuta says.SAJ was established in 1969 and is considered a pioneer in this sector. Its product range covers hydraulic and eddy current dynamometers, chassis dynamometers, control systems, instrumentation and special test rigs, etc. "We also undertake turnkey projects for engine and vehicle testing. Our company's technology centre has been recognised by the Department of Science and Technology of the Government of India. We are also equipped to meet the requirements of the Indian automotive industry taking into account the current emission norms," Rujuta informs. In the auto sphere, SAJ offers end of line chassis dynamometers for 2/3/4 LCV and HCV wheeler vehicles and RLS chassis dynamometer. "We also have on offer various accessories such as universal engine mounting beds, volumetric/gravimetric fuel measurement units, throttle actuator, diesel engine shut-down actuator, etc., along with instrumentation such as temperature/pressure indicators, safety alarm annunciators for measuring and monitoring of critical engine parameters," Rujuta adds. Some of the company's 700-plus clients include Cummins, Lombardini, Ford, Maruti Udyog, Ashok Leyland, Tata Engineering, Eicher, Escorts, Mahindra & Mahindra and others at various locations in India and abroad. SAJ has also been working on development projects with the Automotive Research Association of India (ARAI). "While 80 per cent of our dynamometers find an application in the auto and marine engineering industries, the development of the SH 6700 will now provide us with an entry into a different league altogether. It's not just an engineering marvel but it also proves that India is among the best when it comes to mechanical engineering - something that the developed nations have always found it difficult to accept," Prakash Jagtap states.