How To Check And Accept The Crane After Purchasing?

How to Check and Accept The Crane After Purchasing?
 

Environmental Conditions

 

1. The power supply requirement is three-phase AC, frequency 50HZ, voltage 380V, the upper limit of the allowable voltage switching on the motor and electrical appliances is +10% of the rated voltage; the lower limit (at peak current) is -15% of the rated voltage.

 

2. There must be no flammable, explosive and corrosive gases in the working environment.

 

3. The altitude of the installation site does not exceed 2000 meters, and the motor capacity should be checked when it exceeds 1000 meters.

 

4. The radiation temperature of the hoisted items to the crane does not exceed 400 degrees Celsius.

 

5. The maximum wind pressure in the non-working state of the crane used outdoors is 800Pa.

 

 

Performance

 

1. The lifting capacity of the crane should reach the rated lifting capacity.

 

2. For the hook crane, the braking distance of the hoisting object when it is descending and braking (the controller runs stably at the lowest gear of the descending speed, and after it is pulled back to zero, the distance from when the brake is powered off to when the cargo stops) should be less than 1 1/65 of the stable lifting distance within minutes.

 

3. For hook cranes, when the ascending working level is M4, M5, M6, and the rated ascending speed is equal to or higher than 5m/min, the braking is required to be stable. The method of electric braking should be adopted to ensure that it is 0.2~1.0 When falling within the rated load range, the motor speed before braking drops below 1/3 of the synchronous speed, and this speed should be able to run stably.

 

4. The weight-absorbing capacity of the electromagnetic chuck should not be less than the rated value.

 

5. For a crane with two trolleys, the operation of the same mechanism of the two trolleys should be that the machines can be linked or act independently.

 

 

Selection Principles of Electrical Equipment

 

1. Generally, AC drive AC control system is used. In the case of frequent use or harsh working conditions, DC drive and control system should be used.

 

2. Standard crane electrical control equipment should be used.

 

3. The complete set of resistors for cranes should use standard products. If there are special needs, they can also be designed by the manufacturer, but they must meet the relevant requirements of GB3811-2008.

 

4. Other electrical equipment and components should be selected for cranes or products that can meet the requirements of cranes.

 

5. The supporting products of electrical appliances must have a production license or model use certificate or products that can meet the requirements of the crane.

 

Voltage Loss

 

1. Voltage loss, AC power supply, in the case of peak current, the voltage loss from the bottom busbar of the power supply transformer to any motor terminal of the crane should be less than 15% of the rated voltage.

 

2. Calculation of voltage loss inside the crane

 

 

Electrical Equipment Requirements

 

1. The installation of electrical equipment should be firm. During the working process, there should be no horizontal movement or vertical jump relative to the main machine. The verticality of the control cabinet and screen installed vertically should be less than 12 per thousand. The highest vibration condition of the installation part is: When 5~13HZ, the displacement is 1.5mm; when 13~50HZ, the vibration acceleration is 10m/S2.

 

2. The protection level of electrical equipment installed in the electrical room can be IP00, but appropriate protective measures should be taken.

 

3. Resistors with 4 boxes and below can be stacked directly. When stacking 5 boxes or more, reinforcement measures should be considered and the distance between boxes should be greater than 80mm. If the spacing is too small, the capacity should be reduced or other measures should be taken.

 

4. The electrical equipment installed in each part of it should be able to be easily and safely maintained. Generally, there should be a channel of more than 600mm in front of the electrical equipment on the walking platform and in the electrical room. In special cases, it is allowed to reduce it appropriately, but it should not be less than 500mm.

 

5. For cranes used indoors, the electrical equipment installed on the bridge should have no exposed live parts, and the minimum protection level is IP10. For cranes used outdoors, if the electrical equipment is installed in an unshielded place, the enclosure protection level should not be lower than IP33. In a sheltered place, the enclosure protection level can be appropriately lowered.

 

6. The minimum distance between the exposed live parts of the large crane and the trolley feeder and the metal structure should be greater than 30mm. When the crane may cause relative shaking during operation, the distance should be greater than the maximum shaking amount plus 30mm/

 

 

Other Technical Requirements

 

1. Cool down

 

For cranes working under high temperature for a long time, heat insulation measures should be taken for the driver's cab. Electric control equipment needs to take cooling measures, and fans and power sockets should be installed in the cab.

 

2. Heating

 

According to environmental conditions and user requirements, when setting up heating equipment, non-luminous heaters with fixed protection methods should be used, and electric heaters should use three-phase power supply as much as possible.

 

3. Special requirements

 

For crane electrical equipment used in special environments and working conditions (such as outdoors, high temperature, humid tropics, dry tropics, explosive hazardous media, corrosive media, etc.), the design and selection should meet the corresponding requirements.