A lifting device includes two lifting plates, four rams coupled to the two lifting plates, and a pump coupled to the four rams. Two of the four rams are coupled at two sides of one of the two lifting plates and are configured to move the one lifting plate along a first direction when operated by the pump. The other two of the four rams are coupled at two sides of another one of the two lifting plates and are configured to move the other lifting plate along a second direction when operated by the pump.

A lifting device includes two lifting plates, four rams coupled to the two lifting plates, and a pump coupled to the four rams. Two of the four rams are coupled at two sides of one of the two lifting plates and are configured to move the one lifting plate along a first direction when operated by the pump. The other two of the four rams are coupled at two sides of another one of the two lifting plates and are configured to move the other lifting plate along a second direction when operated by the pump.

An oil returning valve set with multi-stage throttling control includes an oil returning channel implemented in oil in an oil hydraulic equipment. The two ends of the oil returning channel are connected to a pressurized oil collecting cavity and a pressurized oil discharging cavity respectively. A plurality of throttling valve plugs and oil returning valve plug are arranged in the oil returning channel, and a normally-open draining gap is also formed among the plurality of throttling valve plugs. When the oil returning valve plug is opened, a plurality of the throttling valve plugs are arranged in series to generate multi-stage throttling oil hydraulic draining control, which improves the problem that the valve opening allowance of the throttling valve for oil returning and pressure relief of traditional oil hydraulic equipment is not sufficient.

An oil returning valve set with multi-stage throttling control includes an oil returning channel implemented in oil in an oil hydraulic equipment. The two ends of the oil returning channel are connected to a pressurized oil collecting cavity and a pressurized oil discharging cavity respectively. A plurality of throttling valve plugs and oil returning valve plug are arranged in the oil returning channel, and a normally-open draining gap is also formed among the plurality of throttling valve plugs. When the oil returning valve plug is opened, a plurality of the throttling valve plugs are arranged in series to generate multi-stage throttling oil hydraulic draining control, which improves the problem that the valve opening allowance of the throttling valve for oil returning and pressure relief of traditional oil hydraulic equipment is not sufficient.

A coal measures fault formation simulation experimental device and a normal and reverse fault simulation experiment method relate to the field of similar material simulation experiment technology. The device includes a hydraulic lifting apparatus, a lower angle adjusting apparatus, a push rod apparatus, an upper loading apparatus, an upper angle adjusting apparatus, a lateral loading apparatus and a transparent side plate. The hydraulic lifting apparatus and the lower angle adjusting apparatus are below the experimental body, the upper loading apparatus and the upper angle adjusting apparatus are above the experimental body, the transparent side plate is disposed at a rear side surface of the experimental body, and the lateral loading apparatus is disposed at an end face of the experimental body. When the normal fault is simulated with the device, the inclination angle of an inclined plate of the lower angle adjusting apparatus is same as that of an inclined push plate of the upper angle adjusting apparatus, the upper loading apparatus loads downward to form a normal fault.

A coal measures fault formation simulation experimental device and a normal and reverse fault simulation experiment method relate to the field of similar material simulation experiment technology. The device includes a hydraulic lifting apparatus, a lower angle adjusting apparatus, a push rod apparatus, an upper loading apparatus, an upper angle adjusting apparatus, a lateral loading apparatus and a transparent side plate. The hydraulic lifting apparatus and the lower angle adjusting apparatus are below the experimental body, the upper loading apparatus and the upper angle adjusting apparatus are above the experimental body, the transparent side plate is disposed at a rear side surface of the experimental body, and the lateral loading apparatus is disposed at an end face of the experimental body. When the normal fault is simulated with the device, the inclination angle of an inclined plate of the lower angle adjusting apparatus is same as that of an inclined push plate of the upper angle adjusting apparatus, the upper loading apparatus loads downward to form a normal fault.

A coal measures fault formation simulation experimental device and a normal and reverse fault simulation experiment method relate to the field of similar material simulation experiment technology. The device includes a hydraulic lifting apparatus, a lower angle adjusting apparatus, a push rod apparatus, an upper loading apparatus, an upper angle adjusting apparatus, a lateral loading apparatus and a transparent side plate. The hydraulic lifting apparatus and the lower angle adjusting apparatus are below the experimental body, the upper loading apparatus and the upper angle adjusting apparatus are above the experimental body, the transparent side plate is disposed at a rear side surface of the experimental body, and the lateral loading apparatus is disposed at an end face of the experimental body. When the normal fault is simulated with the device, the inclination angle of an inclined plate of the lower angle adjusting apparatus is same as that of an inclined push plate of the upper angle adjusting apparatus, the upper loading apparatus loads downward to form a normal fault; when the reverse fault is simulated, a fault-inducing experimental block is disposed at the bottom of the experimental body so as to form the reverse fault by loading of the lateral loading apparatus. Herein, the technical problem that the dip angle and the fracture initiation position of the simulation fault are inconveniently controlled is solved.

A coal measures fault formation simulation experimental device and a normal and reverse fault simulation experiment method relate to the field of similar material simulation experiment technology. The device includes a hydraulic lifting apparatus, a lower angle adjusting apparatus, a push rod apparatus, an upper loading apparatus, an upper angle adjusting apparatus, a lateral loading apparatus and a transparent side plate. The hydraulic lifting apparatus and the lower angle adjusting apparatus are below the experimental body, the upper loading apparatus and the upper angle adjusting apparatus are above the experimental body, the transparent side plate is disposed at a rear side surface of the experimental body, and the lateral loading apparatus is disposed at an end face of the experimental body. When the normal fault is simulated with the device, the inclination angle of an inclined plate of the lower angle adjusting apparatus is same as that of an inclined push plate of the upper angle adjusting apparatus, the upper loading apparatus loads downward to form a normal fault; when the reverse fault is simulated, a fault-inducing experimental block is disposed at the bottom of the experimental body so as to form the reverse fault by loading of the lateral loading apparatus. Herein, the technical problem that the dip angle and the fracture initiation position of the simulation fault are inconveniently controlled is solved.

A hand held jacking/levelling-tool is provided comprising a jacking shaft and a frame moving relative to each other during jacking action, a caulking gun jacking mechanism providing the jacking action, two outer legs fastened to one of the frame and the jacking shaft and one middle leg fastened to the other of the frame and the jacking shaft being positioned between a left and right outer leg. Furthermore the jacking/levelling tool comprises a foot fastened at a right angle to each leg and pointing in the same direction. The jacking action causes the jacking shaft to move downward through the frame.

A hand held jacking/levelling-tool is provided comprising a jacking shaft and a frame moving relative to each other during jacking action, a caulking gun jacking mechanism providing the jacking action, two outer legs fastened to one of the frame and the jacking shaft and one middle leg fastened to the other of the frame and the jacking shaft being positioned between a left and right outer leg. Furthermore the jacking/levelling tool comprises a foot fastened at a right angle to each leg and pointing in the same direction. The jacking action causes the jacking shaft to move downward through the frame.