We used to have concrete pipe delivered to us by a company that had these self-unloading trailers.The attachment was called a "Pipemaster" and it was a set of heavy forks that were attached to the rear of a high bed trailer.They had a set of hydraulic cylinders and springs attached to the forks for lowering and raising,but don't think they were powered.Basically like large shock absorbers.The truck would pull up to a level area and the driver would start to unload the pipe by just unchaining part of the load.As the load was sometimes tiered depending on the pipe diameter,the driver would take a bar and "coax"the pipe to the forks where they were then lowered to the ground.Two or three on the ground,then the trailer was moved ahead.Did'nt take long to unload either.Anyone seen or used one? Dominion
like the one is this video? http://www.youtube.com/watch?v=3tIerH8HJms&feature=channel_page cool trailers!
Not to hijack your thread, but this trailer showed up on the job to deliver some plastic, trailer all but unloaded itself, I think we rolled 4 pipes off... awesome engineering.