MTS Model 286-20 Confining Pressure Intensifier - Manual (Page 39)

Operating Procedures
286.20 Pressure Intensifier Operation 39
12. On the CPI’s pressure controller, perform the operations necessary to bring
triaxial cell confining pressure to test level.
The CPI’s confining pressure gage will provide an approximate indication of
confining pressure but the readout capabilities of the CPI’s electronic controller
should by used where any precision is required.
cooling and
depressurizing the
triaxial cell
13. After the test is over, perform the operations necessary at the CPI’s pressure
controller to reduce triaxial cell confining pressure to a low level.
14. If the triaxial cell has been heated, adjust the temperature controller
equipment to allow the triaxial cell to cool. See “Cooling The Triaxial Cell
and Confining Fluid” on page 41. It will take several hours for the triaxial
cell to cool, depending on the temperature of the triaxial cell.
15. After the triaxial cell has cooled to, at most, 167°F (75°C), perform the
operations necessary at the CPI’s pressure controller to reduce triaxial cell
confining pressure to zero.
16. After you are certain that confining pressure has been reduced to zero, turn
the Confining Pressure Input valve fully clockwise to Close.
17. At the electronic controller equipment, turn off hydraulic power to the CPI.
18. Slowly open the CPI’s Confining Pressure Output valve to vent residual
pressure, if any, from the triaxial cell.