MTS Landmark Floor Standing - Manual (Page 33)

Description Component Item
Allows the load unit to be moved by lifting the entire load unit. For
load units with the actuator integral to the base, hoist rings are Lift points 13
provided in the crosshead. For load units with the actuator integral
to the crosshead, slings should be used under the crosshead on each
side of the actuator.
Functional Description
The load unit is a stand-alone testing structure. It consists of the following components:
• Load frame
• Crosshead lifts and locks
• Integral actuator assembly
• Actuator
• Servovalve(s)
• Accumulators
• Pressure control
• Transducers
• Grip controls
Load frame
The load frame provides the reaction structure for the force train. The base of the load frame is one side of
the reaction structure and the crosshead is the other side of the reaction structure. The columns complete
the structure. Installing a specimen and other fixtures or components within the structure creates a force train.
The load frame and the other hydraulic components mounted to it collectively create the load unit. Typically,
the base houses the integral actuator assembly (that includes the servovalves and hydraulic manifold).
Typically, the crosshead is mounted above the base by two columns. In some configurations, the integral
actuator beam can be crosshead-mounted.
A control panel lets you operate the crosshead lifts, locks, and grips to assist in specimen installation
procedures. The control panel also contains the Emergency Stop switch and the actuator rod speed control.
Automated crosshead positioning
The crosshead can be positioned anywhere along the load frame columns. This lets you change the load unit
to test specimens of different lengths. It is moved along the columns with hydraulic pressure to both lift and
lower the crosshead; the crosshead has a counterbalance circuit to prevent falling in the event of hydraulic
pressure loss. When the crosshead is in an appropriate test position, it is hydraulically clamped to that position.
Grip controls
The grip controls provide independent clamping control of the upper and lower grips. For most load units, the
pressure is factory set to 21 MPa (3000 psi). There are also optional grip pressures of 45 MPa (6500 psi) or
MTS Landmark™ Floor Standing Load Units Product Information 33
Introduction