Cylinder Load Testing Problems for a Crane

摘要

I WAS TEACHING at a customer when they told me about a large double-acting 10-in. bore crane cylinder, 16 ft long that was giving them problems. Twice a year they would run a test by lifting a large concrete block 12 in. off the ground and check to see if it drifted down more than 1/2 in. in two hours. The cylinder was extended about halfway out for the test.