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January 22, 2010
Technical Bulletin
Engineered Lifting Systems
Tech-Bulletin
for P&H Equalizer Sheave Failure
This bulletin is provided as a
notice to inspect and possibly modify any
existing P&H Balance Design hoist using a cotter
pin as a retaining method for holding the
equalizer pin in place.
Years ago, these pins were always provided with
a two bolt keeper plate with a slot in the end
of the equalizer pin with a grease fitting to
lubricate the equalizer sheave bearing. However,
at some point in time the keeper plate was
replaced with the cotter pin, and no
lubrication.
The cotter pin first became a problem when
without lubrication the bearing would grab the
pin and start to roll the pin in the equalizer
supports. The bolt seen in the drawing was added
to future hoists to keep the pin from rotating
and cutting the equalizer supports.
There is a possibility that the bearing when dry
and worn will grab the equalizer pin and turn
the pin with force in one direction and roll the
pin out of the equalizer pin.
See the below pictures taken after this hoist
dropped a load.

No one was injured; however this equalizer
dropped a load.
Engineered Lifting Systems is
suggesting that if you have P&H wire rope hoists
that your maintenance department checks the
equalizer support bracket, pin and retaining
method for the equalizer pin. Further, a review
to see if there is a lubrication for the
equalizer sheave bearing is recommended.
We can offer a modernization for these to
provide a keeper plate, as well as a lubrication
site, or provide advice on how this can be
completed.

These images above and below show the upgrade to
the pin and equalizer assembly so the sheave
bearing does not rotate the sheave pin.

“Thanks” goes to Crane Boomer at
www.cranewiki.com for use of the picture!
For additional
information please call Eric Brown at Engineered
Lifting Systems 866-756-1200, or e-mail at
ebrown@engineeredlifting.com |