MTS 318 Load Unit - Manual (Page 56)

318 Load Unit 56 Installation
7. Return to the installation procedure.
318 Load Unit: Connect Hydraulics
The procedure describes how to connect the load unit to the hydraulic power
source. The load unit may be connected directly to the hydraulic power unit (also
called HPU), to hydraulic plumbing in the workplace, or through a hydraulic
service manifold.
Note The internal hydraulic connections from the actuator manifold and
accessories such as the hydraulic lifts and locks should already be
made.
1. Connect the return line from the hydraulic power unit to the hydraulic port
on the manifold labeled “R”.
2. Connect the pressure line from the hydraulic power unit to the hydraulic
port on the manifold labeled “P”.
3. Connect the drain line from the hydraulic power unit to the hydraulic port on
the manifold labeled “D”.
4. Turn on the HPU and check for any hydraulic pressure leaks.
5. Turn on the actuator manifold (also called a hydraulic service manifold or
HSM) and check for hydraulic leaks in the load unit.
6. If you have hydraulic lifts, bleed the air out of the hydraulic lift cylinders.
7. Return to the installation procedure.
318 Load Unit: Unlock the Crosshead
When the load unit is shipped, the crosshead is clamped to the columns with the
manual clamping bolts in the crosshead.
Note This procedure only applies to load units equipped with hydraulic lifts and
locks.
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.
1. Turn on hydraulic pressure.
CAUTION