Hoist rope weargreenspun.com : LUSENET : Elevator Problem Discussion : One Thread
Our company recently (18 monthes ago) recabled 8 cars as part of a modernization. the equipment is... WESTINGHOUSE 2050 MACH. #3500 700FPM D.W. 2:1 (undercut U groove) 5 high strength 1\2in 8x19 langlay ropes. (manuf. spec). 21 floors The original ropes had a life span of at least 8-10 yrs. and where not showing any signs of this excessive wear. All sheave grooves and rope tension ok. The newly installed ropes(18 mo.) show signs of extreme crown wear, they are nearly undersized in 18 mo. All cars all ropes are wearing the same. I believe they are from williamsport? All spool info was tossed out. Anyone heard of anything like this?
-- steve carlson (email@example.com), January 28, 2005
I remember some 2:1 job in Ontario perhaps 13 years ago with hoist ropes wearing very quickly and the elevator contractor had 3 theories (maybe more):
1) Bad ropes. 2) The ropes were perhaps very slightly oversized (fraction of a millimetre) and tugging between the hoist sheave and double-wrap offset sheave. 3) The springs on the dead-end hitches were "bottoming" on acceleration or deceleration sometimes and tugging on the ropes.
I don't know what the final outcome was or if a definite reason was found; I was a sub-consultant, just a one-shot visit.
There weren't the rope manufacturer that you mention and I don't remember the equipment except it was 2:1 gearless.
-- Barry Finch (firstname.lastname@example.org), January 28, 2005.
Yes. We had 4 jobs with the same problem about a year ago. Williamsport didn't believe us, so we brought them to the office to personally sample the "bad" ropes themselves. End result, they believe there may have been a problem with the rope but they're not sure. We got credit for the replacement ropes though.
-- Chris (email@example.com), February 01, 2005.
Chris, do you recall the name of the person who came out? Williamsport sent out their area rep and he was not to familiar with elevator cables (he worked mainly with crane cables). He measured them and said the where showing wear. But that was about it and these things are going to be undersized shortly. I don't thing anyone wants to admit anything at this point, any solution is going to cost $$$$$$$. Thanks to all for reply's Steve
-- s.carlson (firstname.lastname@example.org), February 02, 2005.