Applicatin Single screw pump is a new pump working up to the returning volume principle. The main working parts are partial screw bar (returning one) and fixing jacket (fixing one).These two parts form separate sealing container, because of the special geometry patern. The medium evenly flows in the axis direction, the inner flow spead is low, and the container keeps unchanged, so the eddy or agitation will not be formed. The transfer pressure of every class pump is 0.6Mpa,with lift 60m(clean water),self-priming height normally above 6m.Because the fixing one adopts several elastic material, so it fits to transfer high viscosity liquid, and also liquid containing fibers. The flow is in accord with the returning speed, and the returning speed is adjustable by adjusting flow.