The invention relates to an ultrahigh-pressure hydraulic testing
machine for a steel
pipe, in particular to an internal type ultrahigh-pressure
hydraulic pressure testing
machine for a large-
diameter steel
pipe and a hydraulic
system of the
hydraulic pressure testing
machine. The hydraulic testing machine comprises a
piston cylinder body, a
front cover, a rear cover, a
piston, a
piston rod, a rear-end zigzag nut, a front-end zigzag nut, an internal sealing mold and an external sealing mold, wherein the
front cover and the rear cover are located at two ends of the
piston cylinder body; the piston and the
piston rod are located in the cylinder body; the rear-end zigzag nut is used for fixing the piton rod; the front-end zigzag nut is used for transmitting force to a tested steel
pipe; the internal sealing mold and the external sealing mold are used for sealing and fixing the tested steel pipe; an inner cavity of the cylinder body is divided into a rodless cavity body and a rod cavity by the piston. The hydraulic
system comprises a low-pressure oil power
system, an electrical-hydraulic closed-
loop control system, a high-pressure water pump accumulator power system, a low-pressure
water supply system and an
oil pressure driving device. According to the hydraulic testing machine and the hydraulic system, cylindrical
closed space is formed in the tested steel pipe, and an ultrahigh-pressure
hydraulic test can be performed on the tested steel pipe without any other external force; the hydraulic testing machine and the hydraulic system are suitable for the ultrahigh-pressure
hydraulic test of the large-
diameter steel pipe, the equipment weight can be greatly reduced, and the investment can be reduced by times.