Universal Calibrating Machine
(UCM) Manual
(PM-5201)
Morehouse Instrument Company, Inc.
1742 Sixth Ave., York, PA 17403-2675 USA
Phone: (717) 843-0081
www.mhforce.com
Page 20
Rev. 11/2021
With the reference standard in place and the upper yoke platen lowered to rest on the steel loading ball (or
other adapter), release the lock collars, and measure the distance between the upper machine platen and the
lower yoke platen. This distance should be approximately the height of the test instrument plus any acces
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sories or adapters to be used. If it is not, then raise or lower the lower yoke platen until the correct space is
achieved. To raise or lower the lower yoke platen, proceed as follows:
a) Loosen the screws on the tie bar collars and raise them above the upper machine platen.
Caution: Never loosen the screws on the tie bar locking collars unless the reference standard or the hydraulic
jack supports the entire weight of the moveable yoke.
b) Using the motorized adjusting switch, push the switch up/down to raise/lower, the lower yoke platen.
c) When the desired adjustment has been achieved, position the tie bar locking collars to allow clearance be
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tween them and the upper machine platen. Then firmly tighten the screws to hold them in place.
Next, mount the test instrument on the lower yoke platen as shown in Figure 10a. If the test instrument has a
tapped central hole in its base, it should be mounted by an alignment plug to assure proper positioning of the
test instrument on the loading axis of the machine. The alignment plug should be threaded far enough into
load cell to align, not load on the alignment plug. A test instrument with a circle of tapped mounting holes in
its base should be first mounted to an adapter plate that is counter-bored so that all the bolt heads are com
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pletely recessed.
Check for clearance between the adapters used to load against the top of the test instrument and the under
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side of the upper machine platen. This clearance should be approximately 1/8 inch. If the clearance is greater
than 1/8 inch, then raise the lower yoke platen as needed. Always check to be sure there is clearance between
the test instrument, its adapters, and the upper machine platen.
Caution: Never load the test instrument directly against the underside of the upper machine platen. Loading
directly against the upper machine platen may result in high unit stress and damage the platen. Proper acces
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sories, such as alignment bearing blocks or soft steel pads used with hardened steel bearing plates should be
used to decrease the unit stress to safe levels.
