MTS Material Test Systems - Manual (Page 62)

Caution:
Oil spillage can create an environmental concern and a slippery surface.
Slippery surfaces can cause you to fall and incur personal injury.
When changing hydraulic grips, make sure you cap or plug the hydraulic hoses when they are
removed to prevent oil spillage. Promptly clean up any oil that might have spilled when hoses
were removed.
Warning:
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. Prepare the components for specimen installation.
a. Ensure that the crosshead is locked.
b. Turn on system electrical power.
c. Turn on high hydraulic pressure.
d. Set the actuator speed to slow.
e. Enable the handset.
f. Use the handset thumbwheel to move the actuator to its start position (usually mid-displacement). The
starting position of the actuator depends on the type of fixtures, grips, and the test being set up.
Caution:
The crosshead can slowly drift down the columns if the locks are turned off and when
hydraulic pressure is turned off. The crosshead can damage any test fixtures, grips, and
specimen in its path.
Unlock the crosshead only to reposition it. Always lock the crosshead after you have
repositioned it, and never leave the crosshead unlocked.
2. Set the crosshead position.
The crosshead position depends on the length of the specimen being tested, the starting position of the
actuator, and the size of the fixtures or grips being used.
62 MTS Material Test System Operation
7.0 Operation