Instructions For Purchasing Bridge Cranes in Power Plants

Instructions for purchasing bridge cranes in power plants
 

1 Performance requirements
 

1.1 The design and manufacture of the crane should meet the requirements of the relevant codes and standards. The supporting equipment of the crane should not be the equipment banned or eliminated by the state.
 

1.2 Carts, trolleys and lifting mechanisms should have reliable braking systems, end-stroke limit devices and buffer devices. The hoisting mechanism has two ascending limit protection devices, and the crane adopts polyurethane buffers.
 

1.3 All rotating parts should have a reliable lubrication system.
 

1.4 Limit requirements for driving hook
 

2 Welding requirements
 

The welding form and size shall comply with the provisions of GB324-88 "Welding Specifications" and GB986-88 "Basic Form and Size of Manual Arc Welding Joints".
 

 

3 Material Requirements
 

Reasonably select materials for the bridge, trolley, hook and accessories, and the bridge structure adopts Q235 to meet the operation under various conditions. At least the following standards should be met: (if there is the latest standard, implement the new standard).
 

a. GB699-88 "Technical Conditions for High Quality Carbon Structural Steel"
 

b. GB700-88 "Carbon Structural Steel"
 

c. GB1102-74 "Round Strand Wire Rope"
 

d. GB1348-88 "Low Alloy Structural Steel"
 

e. GB11352-89 "Carbon Steel Castings for General Engineering"
 

f. GB9439-88 "Grey Iron Castings"
 

 

4 Electrical Equipment Requirements
 

4.1 Electrical equipment includes motors and their control equipment, and the starting performance should match that of the mechanical parts.
 

4.2 Electrical equipment includes necessary electric motor operators, brakes, controllers, etc., as well as some necessary electromagnetic switches, resistors, overcurrent relays or fuses. speak. Suspension cable conductivity type for trolley conductivity.
 

4.3 The voltage fluctuation range of the motor including the control equipment is 80%-110%, and it is guaranteed to start at 80-100% of the rated voltage and rated frequency. The rated torque of the motor shall comply with the relevant national crane electrical equipment standards, the insulation class shall be F class (the temperature rise shall be evaluated by B class), and the protection class shall be IP44. Motor voltage is 380V.
 

4.4 The motor has sufficient capacity to bear the load of the hoist. Under the conditions of extreme maximum +43.4°C/extreme minimum -20°C and an altitude of 111.5m, the hoisting motor can work continuously for 60 minutes without abnormality. Motors should use anti-friction bearings whenever possible.
 

4.5 Each lifting device should be equipped with an automatic reset limit switch.
 

4.6 The overload limiter (hook) of the device is equipped with an automatic alarm device. Cranes should be equipped with alarm bells.
 

4.7 The section of all wires and cables shall not be less than 1.5mm2 copper core, and all cables and wires shall be of marine type.
 

4.8 There are 4 anti-vibration lights under the driving bridge.
 

 

5 Control and Protection Requirements
 

5.1 Cranes should be equipped with indicating, monitoring and protection equipment.
 

5.2 Electronic control equipment should include the following parts (not limited to):
 

Crane protection box, resistor, operating mechanism control panel, hoisting mechanism control panel.
 

5.3 The crane should have the following protection:
 

Short-circuit protection, grounding protection, over-current protection, voltage loss protection, zero-crossing protection, rising limit protection, stroke protection, emergency power-off protection.