1.Introduction and application-torsion testing machine it is applicable to static mechanical properties test for metallic, nonmetallic materials and various construction member, like transmission shaft and semi-axis; adopting horizontal structure, computer screen display, digital data acquisition and control system as well as fully digital ac servo system; adopting planetary cycloid pinwheel speed reducer to drive, with features of even loading, stability, without impact, accurate data acquisition. if equipped with special grips, it can perform torsional force, torsional angle, and angle stiffness for metals and rubber cohesive layers. parameters modulus g, proof strength, non-proportional torsionp, upper yield strengtheh, lower yield strengthïel, torsional strengthm, etc can be measured and calculted on software automatically. 2. Main technical parameters- torsion testing machine 1Max torque500nm 2Measuring range of torque10nm-500nm 3Torque resolution1/±200000 4Relative error of indicating value of torque1% 5Torsion angle resolution0.01° 6Torsion speed0-360°/min 7Relative error of torsion speedWithin ±1% of set value 8Max distance between grips600mm 9Axiality of two gripsLess than ï1.0mm 10Central height of main axis170mm 11Power0.75kw 12Voltage220v±10% 50hz 13Dimension1750x600x950mm