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About Top Drives

History of Top Drive Development

By Larry Keast, P.E., Founder & CEO

The top drive concept started with the first power swivels in 1948 which were the first hanging devices for rotating the pipe.

To read the history of power swivels, go to our section "About Power Swivels".



About 1960, Baash-Ross was bought by Joy Manufacturing and in 1962 they introduced 65 ton and 100 ton power swivels.         Then about 1980, Baash-Ross introduced well-engineered upgrades of these models, calling them the PS-85 and PS-130.         Sales never amounted to much because they were not hydraulic people and they did not build hydraulic power units.             They had HPU's built by hydraulic suppliers so customer needs and features were never understood.

Other than Bowen, there were only three brands of power swivels designed and built in engineering-based manufacturing companies - Baash-Ross, Homco, and King. None ever competed effectively with Bowen after 1970, whose leadership was due to much more aggressive sales and marketing than the others.


In 1964, Bowen introduced the 85 ton S-2 and the 120 ton S-3.  Early Vickers piston-type hydraulic motors had to be bolted on from the inside of the gearbox before swivel assembly so field replacement was impossible.

Joy Baash-Ross only made power swivels until Varco bought Baash-Ross and discontinued power swivels altogether in the early 90's.


In the 1970's, after not offering a power swivel for years, Homco developed their own ingenious power swivels, but they were too expensive and too large to be practical. They never got off the ground, and after a few years, Homco started buying Bowens for use in their service operations.