Engine Tale. Part 2: Competition Analysis and CrankcasesPosted: February 5, 2016
In PART 1 of this story, I talked about our plans to build improved engines for Agricultural applications for India, South Asia and Africa.
But why engines? and why agricultural applications?
People often ask me this question and the short answer is;
BECAUSE WE CAN DO BETTER
Simply put, we have the ability, in terms of knowledge, people, infrastructure and resources to develop a better engine than the ones currently on the market.
There are are three players who dominate the Agricultural engines market. They are ;
Honda is a world wide leader in the small engines market. Their subsidiary, Honda-Siel Pvt. Ltd., makes small engines for Agro applications in India. Their best selling product, in India, is a 100cc 4 stroke, which produces 1.3kW @ 4200 rpm and 3.9Nm @ 3000 rpm. This is a side valve engine called GK100. As with many small agro engines, it is air cooled.
The engine costs about INR 15,000 in retail.
ii. Southern Agro
Southern Agro engines Pvt. Ltd. is Chennai based company, that manufactures the Vijay Villiers brand of small engines. The Company website claims that they “clinched a technical collaboration with Villiers Limited, UK, to manufacture portable, multi-fuel internal combustion engines” in 1996, though how they made a collaboration when Villiers Engineering went into liquidation in 1978, I don’t know.
At any rate, they make versions of the Villiers Mk12 engine, which produces 1.45 kW @ 3000 rpm for the petrol start and petrol run version. Torque ratings are not available. Being a side valve engine again, the compression ratio is about 4.
The Engine costs about INR 8,500 in retail.
iii. Greaves Cotton
Greaves Cotton Ltd., a company of the Thapar Group, bought two plants from from the Enfield company. The plants were making, guess what? the exact same Villiers engine as the one that Southern Agro makes. Greaves Cotton still makes this engine and also uses it in its range of agro equipment. It’s even called the Mk12!
Although it’s the exact same low compression and low power density engine, it costs slightly more at about INR 10,500 in retail.
So there you have it one over priced engine and under powered engine with the nothing to say for it except that it’s made by Honda. And two manufacturers making the exact same Villiers engine designed in…Wait for it…1936! That’s our competition.
DESIGNING THE ENGINE
Our efforts at taking apart and reverse engineering the Japanese two stroke engine, and our theoretical studies had given us the confidence to begin designing our own engine.
We decided at the outset that;
- We would make the engine modular, so that changes in one part would not drastically affect others. This has the added benefit of being profitable, even at medium volumes, which is what we expect our first 3 years sales to be.
- We would make the engine configurable. We design in such a way that the same engine could be mounted, on a sprayer, or a seed drill, or a water pump or a small marine craft.
- We would make our tooling so that, it could produce various versions of the same part, for example, the same pattern would be used to make aluminum castings (lighter, cheaper to machine, better heat dissipation, more expensive overall) and Cast Iron Castings (Heavier, sturdier, Cheaper overall)
- We would stick with well established materials and configurations, including thermodynamic configurations. However, we would not be tied down by mass production requirements and doing something just because everyone else is.
4 WEEKS LATER…
We modeled the engine on CAD and applied all of the knowledge we had acquired over the last few months.
We were confident that the engine would produce a maximum power of 5kW @ 6000rpm and atleast 3kW @ 3000 ~ 4000 rpm, which seems to be the standard rpm for Agro engines the world over. It would also be capable of 7 ~8 Nm of torque in the usable range of rpm. A huge increase in power density and efficiency over the engines available in the market!
The first assembly we decided to make, was the Crankcase.
We made detailed engineering Drawings for both halves of the crankcase
But before we could go about machining it, we had to first cast it.
We took a big chunk of aluminum and put it on our CNC machine and made a pattern. We designed it so that the same pattern could be used for both halves of the crankcase
We took the patterns to our friendly neighborhood Aluminum foundry, Varsha Castings, Peenya, and got some sand castings made.
Because our machines were fully occupied at the time, we got the prototype machining done by Maestro Tech, Peenya. And I must add, Girish Shetty, the proprietor, did a wonderful job.
The parts assembled flawlessly.
We put some of the parts of the original study engine on the crankcase assembly, cobbled up a makeshift starting arrangement and …
So now that we know the crankcase is OK (big sigh of relief!) we decided to attack, what is arguably the most important part of a 2 stroke engine, the Cylinder.
More on that in PART3