59results about How to "Stable and reliable pressure" patented technology

The invention discloses a foundation pit construction method suitable for a soft substratum. The method comprises the following steps that a waterproof curtain is constructed at the boundary positionof a foundation pit to be subjected to excavation, supporting piles are constructed on the inner side of the waterproof curtain, and the waterproof curtain and the supporting piles go deep into the soft substratum; multiple underground diaphragm walls perpendicular to the excavation longitudinal direction of the foundation pit are constructed in the longitudinal direction of the foundation pit tobe subjected to excavation, the bottoms of the underground diaphragm walls go deep into the soft substratum, and multiple composite foundation piles are constructed between the adjacent underground diaphragm walls; multiple reinforcing columns are constructed on the inner sides of the supporting piles, the reinforcing columns are fixedly embedded between the underground diaphragm walls and the supporting piles, and the bottom ends of the reinforcing columns go deep into the soft substratum; and foundation pit excavation is conducted until the first set depth is reached. According to the construction method, a supporting structure is high in reliability, and the cost is low.

The invention discloses a multiple-cylinder linkage hydraulic machine hydraulic system use method, and belongs to the technical field of hydraulic machines. The method comprises the control steps of main oil cylinder rapid down, main oil cylinder slow down, main oil cylinder pressure maintaining, main oil cylinder pressure release, main oil cylinder return and the like; when main oil cylinder rapid down is performed, a cartridge valve III, a cartridge valve VII and a cartridge valve VI are switched on, a cartridge valve IV is switched off, an upper cavity of a main oil cylinder is subjected tooil taking, and a lower cavity of the main oil cylinder is subjected to oil return; when main oil cylinder slow down is performed, a cartridge valve VII and a cartridge valve V are switched on, the cartridge valve VI is switched off, the upper cavity of the main oil cylinder is subjected to oil taking, the lower cavity of the main oil cylinder is subjected to oil return, and a workpiece is pressed; when main oil cylinder pressure maintaining is performed, the cartridge valve VII and the cartridge valve VIII are switched off, oil lines of the upper cavity and the lower cavity of the main oil cylinder are disconnected, and the main oil cylinder is locked; when main oil cylinder return is performed, the cartridge valve III is switched off, the cartridge valve IV and the cartridge valve VII are switched on, the lower cavity of the main oil cylinder is subjected to oil taking, and the upper cavity of the main oil cylinder is subjected to oil return. Accordingly, control over actions such as large hydraulic machine rapid down, slow down, pressure maintenance, pressure release and return can be achieved stably and reliably.

The invention provides an oil pump for a connecting rod-free reciprocating-rotating movement conversion mechanism. The oil pump comprises an oil inlet joint and an oil pump body, wherein the oil inlet joint is arranged at the bottom of a single-action piston; a first oil duct which is communicated with a piston oil duct of a piston body is axially arranged along the oil inlet joint; the oil pump body comprises a pump body and a plunger; a plunger cavity which is opened on the top of the pump body is arranged in the pump body, and an oil inlet is formed on the pump body; the plunger is a column body arranged in the plunger cavity, and an axial second oil duct is arranged in the middle of the plunger; the plunger can move axially along the plunger cavity, when the piston moves toward an oil pan, the oil inlet joint is inserted into the plunger cavity and props against the top face of the plunger, so that the piston moves downward along the plunger cavity; and simultaneously the first oil duct is communicated with the second oil duct. The oil pump can be used for pumping oil into a lubrication loop of the body from the bottom of the oil pan, is reliable in engine oil pressure, and can guarantee the lubricant supply of the mechanism.