Brief introduction and selection of electric hydraulic grab

Brief introduction of electric hydraulic grab 

Electric hydraulic grab is a kind of grab with its own motor, hydraulic system and so on, which is driven by power supply to open and close. The grab depends on the positive and negative rotation of the motor or the hydraulic reversing valve to control the opening and closing of the grab. The electric hydraulic bulk grab is an effective tool for bulk loading and unloading of yellow sand, coal, mineral powder, ore, cement, etc.

The grab has its own hydraulic system, and the main components of the hydraulic system, such as valve group, seal, valve block, etc., are European and American brands. Constant power pump and hydraulic servo system are adopted in the hydraulic pump. The output of pump can be effectively controlled by the change of system pressure. When the maximum pressure is reached, the flow of the pump is very low, which greatly reduces the overflow, reduces the energy consumption, reduces the oil temperature, so as to make use of the long-term continuous work and greatly improves the production efficiency. The grab has the advantages of simple structure, convenient operation, and can work in various harsh environments. The unique curve of jaw flap is particularly conducive to the loading and unloading of various bulk cargoes. The upper part of grab bucket is equipped with cable interface, which is convenient for connection with crane.

Classification and application of electric hydraulic grab

Electric hydraulic grab can be divided into the following types according to its structure：

1) Electro-Hydraulic Clamshell Grab: It is mainly used with single hook crane to grab all kinds of bulk cargo, commonly used in ships, docks, etc. 

2) Electric hydraulic multi flap Grab: mainly used with single hook crane to grab domestic garbage, scrap and other materials, commonly used in environmental power plants, steel plants, etc. 

3) electric hydraulic wood Grab: mainly used for loading and unloading logs with single hook crane, commonly used in wood yard, wharf, etc.

4) electric hydraulic rectangular Grab: it is mainly used with single hook crane for cleaning domestic garbage in waterway, or for loading and unloading waste steel in train carriage in steel plant.

5) Electric hydraulic straw Grab: mainly used with single hook crane for loading and unloading of straws, which are often used in environmental protection power plants.

Structure of electric hydraulic grab

The electric hydraulic grab is composed of the following components:

1）Barrel;

2）Bucket flap;

3）hydro-cylinder;

4）Motor;

5）Hydraulic pump station.

Structure of electric hydraulic grab

Working principle of electric hydraulic grab

Open cycle I： When the motor is running, the hydraulic pump pumps the hydraulic oil from the oil tank. When the grab needs to be opened, the hydraulic oil flows to the rod cavity of the oil cylinder through the pressure pipe through the check valve. At the same time, the pressure oil will open the oil return port of the hydraulic control check valve, the oil in the rodless chamber of the oil cylinder will flow into the oil return pipe, and return to the oil tank through the oil return filter. As the cylinder rod retracts to the cylinder barrel, the grab gradually opens.   when the motor is closed, the check valve and hydraulic control check valve can lock the oil pressure in the cylinder to prevent the grab from closing automatically

Closed cycle II： When the motor is running, the hydraulic pump will pump oil into the pressure pipe, operate the electric control box, and the hydraulic oil will enter the rod free chamber of the cylinder through the check valve and the pressure pipe. At the same time, the pressure oil will open the control oil passage of the hydraulic control check valve, so that the hydraulic oil in the rod cavity of the cylinder will flow back to the oil tank through the pressure pipe and the hydraulic control check valve, through the return pipe and the oil filter

Advantages of constant power pump electric hydraulic grab

1. The main components of the hydraulic system, such as valve group, seal, valve block, etc., are of international famous brands to ensure product quality.

2. Constant power pump and hydraulic servo system are adopted in the hydraulic pump. The output of pump can be effectively controlled by the change of system pressure. When the maximum pressure is reached, the flow of the pump is very low, thus greatly reducing the overflow, reducing the energy consumption, reducing the temperature rise, so as to ensure that it can work continuously for 24 hours.

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