RIGCHINA-EP Lubricity Tester | Model RCLT-212 | measure the lubricating quality of drilling fluids0 pages
Drilling Fluids
EP/Lubricity Tester
Model RCLT-212
Combination EP Lubricity Tester
Manifestation of friction between
the drill string and the borehole is
as old as drilling itself. Frictional
resistance to rotation of the drill
string is called torque, and frictional
resistance to hoisting and lowering
the drill string is called drag. Many
different materials have been used
as drilling fluid additives to improve
lubricity, thereby reducing friction.
The lubricity test was designed to
simulate the torque and drag
produced by a given drilling fluid
down-hole.
The
tester
approximates the speed of rotation
of the drill pipe and the pressure
with which the pipe bears against
the wall of the hole where the
friction is generated.
Extreme pressure lubricants have been developed to increase the life of bit-bearings. Extreme
pressure lubrication deals with metal surfaces in rubbing contact with each other at very high
pressures (e.g., 30,000 to 100,000 psig (206,820 to 689,400 kPa)). Lubrication for the metal surfaces
is provided by a pressure resistant film that is produced as a result of the chemical reaction initiated
by a high temperature generated from friction at the area of contact.
The RIGCHINA Model RCLT-212 Combination EP (Extreme Pressure) and Lubricity Tester is a
high-quality instrument designed to measure the lubricating quality of drilling fluids, provide data to
evaluate the type and quantity of lubricating additives that may be required, and predict wear rates of
mechanical parts in known fluid systems.
EP tests are performed by applying a measured force with a torque arm to a torque-sensitive, rotating
bearing cup. This provides a means of testing lubrication under extreme pressure conditions and
produces an indication of the film strength of the fluid being tested.
The problem of reduction of friction between the drill string and the borehole requires a different
simulation. The more common lubricity test measures fluid resistance (lubricating character) between
two hardened steel moving surfaces at a hundred pounds force (which translates into a 5,000 to
10,000 psig (34,470 to 68,940 kPa) pressure on the intermediate fluid film). During the lubricity test, a
steel block is pressed against a rotating steel ring. Load in inch-pounds is read directly from the dial
on the torque arm.
Rigchina Group Co. China
No.80-82, Qiude Rd,west Chengbei Industrial Estate
Yongkang, Zhejiang, China 321300
Phone: + 86 - 579 - 87537 698(Switchboard)
Fax: + 86 - 579 - 87537 696
Email: sales@rigchina.com
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