Mechanical Cryostat for Characterisation of Advanced Materials Down to 4K

Tender description

A cryogenic mechanical test station comprising of a 250 kN hydraulic test frame and a 250 kN load rated cryostat. The cryostat must be suitable for mechanical testing at 4K by immersing test rigs in liquid helium, at 20K in gaseous helium, at 77K in liquid nitrogen and room temperature. The mechanical test frame must have a top mounted hydraulic actuator with sufficient working distance to enable the halves of the cryostat to be separated on specimen removal and loading. Liquid helium and liquid nitrogen dewar feeds are required. Lot 1: A 250 kN Servo Hydraulic Fatigue 2 column test system with actuator in crosshead with stroke of ±75mm. The test system should have a 1200 mm Tee slot table @590 mm from the floor. Height should provide at least 2690 mm working distance between table and underside of crosshead. Fitted with telescopic lift cylinders. Actuator displacement measurement accuracy of better than ±0.2% of transducer full travel. Load measurement accuracy to 1/250th of loadcell full scale. Adaptive control system allowing continuous update of PID settings at 1 kHz. Control loop update (10 kHz) on call control axes and continuous synchronous data acquisition at 10 kHz on all sensor channels. Mixed-mode control technology allowing bi-modal and tri-modal control techniques to be used. Mechanical test system fitted with a 250 kN fully Reverse-Cycle-Fatigue-Cryostat consisting of a self-reacting load frame and cryogenic test chamber that mounts to the underside of the test machine’s upper crosshead. The cryostat should be suitable for quasi-static and mechanical testing at fixed point temperatures of 295 K, 77 K and 4 K. The cryostat should include hardware necessary to conduct temperature-controlled tests at intermediate test temperatures in the range from 20 K to 300 K. Cryostat and test fixturing must be instrumented with temperature sensors and resistive heating elements. A four channel PID temperature controller should be provided to monitor the specimen and chamber temperature and to supply the heating power.