MTS Material Test Systems - Manual (Page 64)

Caution:
Oil spillage can create an environmental concern and slippery surface that can cause personal
injury.
When changing hydraulic grips, make sure you cap or plug the hydraulic hoses when removed
to prevent oil spillage.
Promptly clean up any oil that might have spilled when hoses were removed.
Caution:
The crosshead is very heavy.
A dropping crosshead can crush hands, damage grips, and smash specimens.
Be careful when working in a crush zone. To reduce the hazards in this procedure, observe the
following: Set and enable displacement interlocks to limit the actuator’s movement. Ensure that
the crosshead is locked. Ensure that the columns are clean and dry. Keep your hands out of the
crush zone except when performing the steps needed to complete this procedure.
1. Select load control for specimen installation .
2. Clear active interlocks.
3. Apply hydraulic pressure .
4. Retract actuator rod .
Slightly adjust the Set Point control in a direction to apply a small tensile force that will fully retract the
actuator rod. (Doing this provides a known reference for measuring the crosshead position.)
Warning:
A reaction against the load cell can cause unexpected actuator movement.
Unexpected actuator movement can cause serious injury and equipment damage.
Do not touch the load cell or come in contact with the path of the actuator when measuring
the crosshead height. When measuring the height of the crosshead, place the measurement
away from the load frame's crosshead, load cell, and hydraulic actuator, and then sight straight
across for an accurate measurement.
5. Position load frame crosshead to the desired height.
64 MTS Material Test System Operation
7.0 Operation