OfiTE 112-00 - Seizure and Pass Identification

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10. Position the torque arm so that the arm ts inside the concave portion of
the torque arm clamp.
11. Fill the stainless steel sample cup with test uid (260 – 280 mL) and
place it on the lowered cup stand. Raise the cup stand until the test ring,
test block, and block holder are submerged. Tighten the thumbscrew to
secure the cup stand.
Never apply torque to the test block until it is submerged in uid.
12. Rotate the torque adjust handle clockwise so that the reading on the torque
wrench increases at a rate of no more than 5 in-lb per second. Continue
until the torque wrench reading reaches:
a. The desired load (a “PASS”) occurs without seizing or.
b. Until a seizure occurs.
If a seizure occurs, quickly record the readings on the torque wrench and
on the display screen, then remove the load.
Due to the extreme friction between the ring and the block, the uid
will get very hot and may reach the boiling point.
A seizure is dened as tearing and galling (scarring) of the metal to metal
contact between the test ring and the test block surface. This represents a
complete breakdown of the extreme pressure lubricating ability of the uid
or mud under the test conditions. A seizure is identied by:
1. The initial and rapid (not slow) rise in the torque reading. It may
also appear as a sharp, substantial increase in the torque reading
(current), which then drops back to normal. This type of seizure
usually occurs at a relatively low torque reading or during tests of
highly abrasive muds or muds containing a high solids content.
2. An obvious change in the pitch (sound) of the machine (a rasping
sound).
3. The machine begins to vibrate as indicated by rapid uctuations of the
torque gauge needle.
After a seizure, the wear surface on the test block will be very large and
will appear rough and scarred.
If it is desirable to know how a uid behaves at a given torque:
12. Repeat steps 1 through 10 until a “PASS” is obtained. A “PASS” is
identied in one of two ways.
a. A ve minute run at a constant load during which the torque meter
reading remains essentially constant and the wear surface is small
and polished.