The high-pressure cylinders are equipped with buffer devices, and the throttling of hydraulic oil is used at the end of the piston stroke to complete the buffer function, and the pressure exceeds 100Mpa when buffering, and the pressure resistance of the cylinder head and piston is very high, and the hydraulic system is in an overflow state in the buffering process, and the energy consumption is large. The product adds a buffer valve to the crude oil cylinder, and adopts the double buffer mode of high-pressure chamber unloading + low-pressure chamber back pressure, which solves the problem of excessive pressure and high-pressure overflow of the system during buffering, eliminates collision, and reduces the buffer pressure by more than 50% on average.