After having calculated bolt stiffness, or measured the load-deflection curve directly, the best way to calculate pre-load is to measure the extension of the bolt directly. This method is preferred for con rod bolts and all con rod and bolt suppliers generally recommend this method. The fasteners require design features to allow measurement with a special micrometer. This method is impossible for fasteners in blind holes. For large fasteners in blind holes the extension can be measured...
Love them or hate them, the two-stroke engine is in many ways far superior to its 4-stroke rival. Specific power, specific weight, manoeuvrability, cost of manufacture, ease of maintenance, durability, NOx emissions and even fuel consumption in the case of smaller engines, can be far superior to its less controversial 4-stroke brother, but why then don’t we see more of these engines in competition? With one strike for power and one to wear it out as opposed to one of power and three...
It is surely an obvious statement of fact that what goes in, will eventually come out again – somewhere! Filling the bath with water and then watching it drain away again afterwards is an example. The joy of watching the bank balance rise at the end of the month and then tearfully watching it ebb away again in the weeks following, is another. But unlike these examples, which would appear to happen without any effort at all, the task of extracting the oil out of an engine comes at a...
Keeping a piston’s top ring land from experiencing critical wear is a problem that every engine builder experiences, particularly in the hard fought world of NASCAR Sprint Cup Series competition. Dr Andrew Randolph of Earnhardt Childress Racing (ECR) Engines has worked endlessly to remedy the problem. “As rings get closer and closer to the top of the piston, they get so hot that the aluminium melts and adheres to the piston. Not long after that, the piston begins to fail.”...
I have to admit that at the moment, visits to our capital city are few and far between. The heart of business and finance maybe the place where many a motor sport deal is done, but the real action as far as I am concerned, is always in the workshop or on the track. But on those very occasional sojourns when needs must and when using the underground ‘tube’, I’m always reminded of one critical aspect of the piston ring. You see, at many of the stations when the train is just...