
A seizure is defined 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 fluid or mud under the test conditions. A seizure is identi-
fied by a rapid rise in the torque reading. It may also appear as a
sharp, substantial increase in 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. A seizure is also accompanied by an obvious change in the
pitch (sound) of the machine (a rasping sound). After a seizure, the
wear surface on the test block will be very large and will appear rough
and scarred.
11. Repeat steps 1 through 10 until a pass is obtained. A pass is identified
in one of two ways.
a. A five minute run at a constant load during which the torque meter
reading remains essentially constant and the wear surface is small
and polished.
b. A five minute run in which there is a moderate amount of torque
meter deflection and the wear surface is moderate, and may either
be polished or dull, depending upon the abrasiveness of the test
fluid.
12. After removing and cleaning the test block (see "Disassembly" below),
examine the test block for wear. With the aid of a magnifying glass
(part #111-11), observe the scar left on the block by the test ring. If the
scar is rectangular, the test block is properly aligned in the holder. Your
test is complete. If the scar is triangular or trapezoidal, the alignment is
off and must be corrected. Refer to the "Repositioning the Test Block"
section.
1. Record the lowest torque wrench reading (in inch-pounds) and the
average torque meter reading (display screen) at which the seizure
occurred.
2. Record the following at the conclusion of a pass or if a 5-minute test
does not produce a seizure.
a. Torque meter reading in inch-pounds.
b. Scar width in inches (refer to page 14).
c. Film strength in PSI. This value must be calculated. (refer to page 14)
d. Average current (torque reading on the display screen in pounds
divided by 10) in amps.
OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: 832-320-7300 / Fax: 713-880-9886 / www.ofite.com
9
EP Test
Reporting Test Results
Note