A kind of hydraulic control system and control method for pushing blank cylinder forward of punching machine

Abstract

The invention provides a hydraulic control system and a hydraulic control method of a front blank pushing cylinder of a perforating machine. The front blank pushing cylinder comprises a rod cavity and a rodless cavity, a hydraulic oil pipe comprises a pressure oil pipe and an oil return pipe which are respectively communicated to a proportioning valve, and the proportioning valve is communicated to the rodless cavity through a first pipe and communicated to the rod cavity through a second pipe. A valve for achieving forward breakover and reverse check is arranged on the second pipe. The rod cavity is communicated to the pressure oil pipe through a third pipe, and a valve for achieving reverse breakover and forward check is arranged on the third pipe. Compared with the prior art, the using amount of the valves is decreased, and multiple control actions are finished by utilizing one proportioning valve. The impact shake and slight pause problems when the blank pushing cylinder is switched from rapid speed to work speed are effectively solved. In addition, the design capacity of the hydraulic system is effectively reduced by utilizing two non-return pipes, and the manufacture cost is reduced.

Description

technical field [0001] The invention relates to a piercing machine control technology in the production of seamless steel pipes, in particular to a hydraulic proportional control system and a control method for a steel pipe piercing machine forward blank cylinder. Background technique [0002] In the steel pipe piercing machine, the action sequence of the push cylinder is: from fast forward to work forward (slow speed) and then to fast return. like figure 1 As shown, the pushing cylinder 7 has a rodless cavity 71 and a rod cavity 72 . There is a valve block 8 in the valve frame 9 of the hydraulic control system of the pushing cylinder 7, and the valve block 8 includes a left electromagnetic valve 81, a left throttle valve 82, a right electromagnetic valve 83 and a right throttle valve 84. [0003] The above-mentioned actions of the pushing cylinder 7 are controlled in combination by the left electromagnetic valve 81, the left throttle valve 82, the right electromagnetic va...

AI Technical Summary

Problems solved by technology

Design the system capacity according to the existing hydraulic control schematic diagram, often the capacity of the hydraulic station is relatively large

[0010] (3) The existing hydraulic control system is also relatively complicated, the valve block 8 is too large and difficult to process, and it is difficult to find faults

[0011] (4) When the system is shut down for a long time or the punching machine is overhauled, if there is residual pressure in the entire system, the pusher cylinder 7 will automatically go out, which is also a big safety hazard

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