Direct assembly of the tension spring limit test sample fixture rock formula

Direct assembly of the tension spring limit test fixture rock specimen type, the upper jig and the lower jig composition, comprising a lower clamp connected to the tester at the bottom joint loading base, the lower end cap is secured a sample, the lower connection fitting chain under the lower end cap, a first coil spring, the first center and the second center stopper mechanism limiting means; loading base comprises an upper clamp connected to the connector on top of the test machine, the upper end cap is secured a sample, and connecting the joint chain on the upper end cap, a second coil spring, the third and the fourth center center stopper mechanism stop mechanism; the first central stopper mechanism, a second central stopper mechanism, the third and the fourth center stopper mechanism stopper means by the central spring retainer assembly, the support member and the conversion board; spring retainer assembly includes an annular support, three screws, three threaded sleeve with an external thread and an internal thread, three hold down spring and three stopper body.