Testing Machines : Tri-Axial

5 Million lb Capacity Tri-axial Large Structure Testing Machine

Model 828901

The Chant Model 828901 is a large servo-hydraulic testing machine. This is one of the worlds largest machines used to structurally test 8 ft. x 24 ft. sections of ships hulls. The physical size of the machine is approximately 40 ft. long x 25 ft. wide x 15 ft. tall.

5 Million lb Capacity Tri-axial Large Structure Testing Machine

There are a total of 22 hydraulic actuators that generate the testing forces. Each actuator comprises a single rod hydraulic cylinder with swivels installed on each end, internal displacement transducer and a Moog servo valve. Longitudinally there are 10 ea. hydraulic cylinders that generate 5 million lbs. of tension or compression force. Laterally there are 12 ea. Hydraulic cylinders that generate up to 1.2 million lbs. of force. In the base of the structure are water bags that generate up to 700,000 lb. of force on the test specimen at 25 psi. The frame is made of rolled steel beams that are designed to take the combined loading forces either in tension or in compression. The minimum stiffness of the frame structure is 20,000,000 lbs./inch and is designed to withstand a racking of 10% of full load.

In use, this machine uses a Chant Engineering designed real-time computer controlled servo-hydraulic system to simultaneously push and pull steel hull sections with up to 5 millions lbs. of force longitudinally, 1.2 million lbs. of force laterally and 700,000 lbs. from below. All individual actuator forces and displacements are controlled by and displayed on the computer. The specimens are strain gauged by the user and the results displayed on a separate computer. All controls are in a soundproof operator control room.

Chant Engineering manufactured the complete machine. Chant fully assembled and tested this servo-hydraulic testing machine in our shop, did run off testing, then disassembled, and erected the machine on-site. We completed the final acceptance testing with the customer’s specimens on-site.