By: Divya Sudarsanan
Trailblazers in the gear manufacturing industry, and a five-decade run family business, Tarun Nahata, Partner of RDMC, spoke with Gear Technology India of their journey, the defence sector, the challenges of the Indian gear industry and more.
Journey of RDMC
In 1972, RDMC was started by Tarun Nahata’s father, JK Nahata. Tarun Nahata says, “He came with a mindset that he wanted to enter into the manufacturing of heavy engineering segment. He chose this segment because he wanted to add value rather than do a run-of-the-mill job. He started off with earth moving and off-highway segments.”
RDMC is predominantly into manufacturing of high precision gears and CNC components for the off-highway, locomotive, defence, marine, windmill, cement, and tanks.
“We have partnered with all our customers, and proudly say that in the 50 years of journey, they are still with us. We benefit from not just being a partner to them, but also being a partner to learning from them which has been very huge,” he adds.
Exports
RDMC is committed to delivering world-class products. He says, “We do export to the European and the North American markets, and we have the top-of-the-line customers like Caterpillar, Renk and Flender to name a few.
These are the world leaders in whatever they do. We only follow the world leaders, and try to make a niche, by giving them the best product that India can give.” One of his proudest moments was when a customer commended their superior work stating that their work was parallel with German gear manufacturing, if not better.
Maximum Size of Gears
He says, “Typically, we do gears for gearboxes and transmissions and we have the capacity to do up to 1.8 meter external gears in finished cut, and up to 1.5 meter we can do ground gears. We can give them accuracy of DIN 6. In aerospace components that we do, we typically try to do it within DIN 4 and 5.”
In addition, RDMC does high precision and high-speed gears for the textile and printing machines, especially printing machines where the RPM goes about 70,000.
The gears are explicitly qualified for DIN 5 accuracy. “Our manufacturing resources have the best grinding, hobbing, and testing machines. We have everything on top of the line, you could say, the Bentleys and the Bugattis of the gear industry,” he matter-of-factly states.
Gears in Different Segments
RDMC’s gears are used in windmills, and industries such as cement plants, steel mills, sugar mills, and power plants. He notes, “We also do gears for winches. Sometimes, we do get some requirement from the Army for their old gearboxes for rehauling and refurbishing.” Besides this, they also do gears for the marine industry. They also happen to be globally certified. Nahata explains, “You need a certificate. Only then can you qualify as a supplier, and we are. We are certified, so globally any of their franchisees can come to me.”
Defence Sector
RDMC has also made its mark in the defence industry which is a growing sector, and elaborates on the progress they have made. He says, “We are currently doing one of the most complex gears for the transmission of the T-72 and T-90 tank.
We have successfully completed the carrier assembly, and now the sun gear train where there are three different sun gears wherein the wall thickness is very less, the accuracies after gear cutting are within 18 microns; the runout after induction hardening and wall thickness is so less, which initially when we had a look, we said, ‘I think we are going to burn our hands,’ and we did lose a lot of jobs on the path. But finally, when we succeeded, it was a fantastic process that we got in control. It was phenomenal because we could see the repeatability of that.”
They were also a part of the ATAGS – Advanced Towed Artillery Gun System. He proudly notes, “We have been given a certification by Tata SED for successfully proving out the breach to housing, and breach to assembly, which was used for the ATAGS that did a firing of 48 kms with a barrel of Ø155 mm, and broke the world record. The MoD also appreciated us through TATA SED.” Besides this, Nahata is also involved with the K9-Vajra tanks for L&T.
Accuracy Maintenance Range
He explains, “The accuracies that we maintain are definitely precision in terms of gear quality DIN 5/6. We can do DIN 4 but that is on the tooling level where everything is pre-conditioned, the tooling, the temperature. We did a slender gear for one of the satellite programs where the precision was for DIN 4.
The runout between the spline and the gear was about 12 microns. So it was a lot of effort to get that accuracy, and we achieved it.” In addition, they are also working on the T-72 tanks, which is a gost standard. “People are terrified of the gost standard because they don’t know what the top or bottom limit is.”
Facilities & Expansion Plans
RDMC has three units in Bangalore’s industrial hub within a one-kilometre radius in Peenya. Each unit houses a different function right from CNC machining and gear finishing to hobbing, shaping and gear grinding. As for their expansion plans, Nahata is looking at getting into the heat treatment process. He says, “Right now our contribution is maybe 10% of our turnover, but we are looking at getting 30%.”
Technology Upgradation
The company is focused on getting more precision gears as far as technology upgradation goes. That being said, RDMC also keeps themselves abreast of the latest technology in the market. He notes, “Gear skiving is another disruptive thing that is coming up.” However, Nahata remains sceptical where technology and manpower resources are concerned. He opines, “Personally, I would prefer to maintain a balance between the workforce and using the technology,” whilst adding, “Technology, for me, is like a tool which will serve as an extended arm. I don’t believe in doing away with manpower. I’d rather connect with more people than machines.”
India and the Gear Industry
Nahata believes that it’s India’s time to shine. He refers to Mr. Modi, who stated that India is in a period of amrit kaal which translates to “golden period.” With the unfortunate war in Ukraine, and recession-hit US, all signs point to manufacturing coming back to India. He says, “The domestic market is going to be propelling forward especially locomotives, road construction, and defence. We see huge prospects in these segments. Railways is going to be on track for the next ten years.
Off-shore markets like windmills will pick up some speed. If we take a measured vision, we will definitely grow.”
Challenges in the Indian Gear Industry
The need for a good heat treatment source is one of the biggest hurdles in the gear industry. He says, “Heat treatment is an important process and the fate of the gear largely depends on the success of this process. Attaining the right microstructure, hardness, case depth, while maintaining the mechanical properties and not displacing the dimensions is key to a good quality gear. Unfortunately, due to various reasons, India is yet to master the art of heat treatment unlike Europe and the US. There is a lack of consistency in the process affecting the gears’ subsequent processes like OD/ID grinding, gear grinding or even machining (Turning, VMC, and HMC). If this hurdle is overcome, I am 100% sure that India would be at par with Europe and other countries that manufacture precision gears.”
He continues, “Another challenge that this industry faces, and I am sure my peers, too, would agree is the availability and retention of skilled manpower. Post pandemic this challenge has magnified leaving the industry high and dry with an empty pool of skilled manpower resources. I feel that this needs to be taken up as a common cause, and the industry together must come up with a solution to overcome this obstacle by training more and more people, standardizing the pay package, and incentivizing this industry.”
The third problem that he sees is resources, particularly power. He says, “We don’t have an uninterrupted supply of power, and as a result, this leads to a huge production loss and rejection.” He also touches upon the kind of raw material that is supplied. “Right now, that has changed but that has been marred by Chinese suppliers, and local suppliers who sell composite material that’s mixed with we don’t know what. So that’s why the MNCs have standardized their vendors. Competition is good but not at the risk of one’s business. It’s not a healthy practice,” he concludes.
