2results about How to "Stable and safe lifting" patented technology

This utility model relates to the technical field of oil drilling and production equipment, and discloses a pneumatic system for lifting the roof of oilfield cementing equipment. It includes a roof cylinder and a pressure reducing valve connected to an air supply source via an air inlet. The outlet of the pressure reducing valve is connected to the inlet of an electromagnetic directional valve via an air pipe. The first and second outlets of the electromagnetic directional valve are respectively connected to the inlets of a first and second speed control valve. The outlet of the first speed control valve is connected to the inlet of a pneumatically controlled check valve, and the outlet of the second speed control valve is connected to the feedback port of the pneumatically controlled check valve. The outlet of the pneumatically controlled check valve is connected to the rodless chamber inlet of the roof cylinder, and the feedback port of the pneumatically controlled check valve is connected to the rod chamber inlet of the roof cylinder. This utility model's pneumatic system for lifting the roof of oilfield cementing equipment indirectly controls the lifting of the roof by controlling the extension and retraction of the roof cylinder through the electromagnetic directional valve. It has good performance and a simple control method.

The utility model relates to a lifting type operation platform for bridge pier hoisting fence installation belongs to bridge engineering construction technical field. It is in to provide a kind of lifting type operation platform that can be conveniently, safely installs hoisting fence on the bridge pier of higher or has been framed beam. Adopt following technical scheme, including walking platform, electric hoist, fixed steel wire rope and drooping steel wire rope, the walking platform is annular, surrounds in bridge pier outside, four electric hoists are fixed on walking platform, four electric hoists are in a group, respectively located bridge pier two sides, and each electric hoist is located on the midline extension line of two cushion stones;Two fixed steel wire ropes are respectively looped on two cushion stones, and two drooping steel wire ropes are symmetrically connected on each fixed steel wire rope, the upper end of drooping steel wire rope is connected on fixed steel wire rope, and the lower end is dropped to bridge pier side and is connected with the lifting hook of electric hoist located directly below it. The utility model is used for installing hoisting fence construction on bridge pier.