Cranes are often used in industrial consumption, of which gantry cranes account for the majority, so we should pay more attention to the inspection of gantry crane equipment and the inspection of maintenance grounding, only in this way can we really ensure the integrity and safety of the equipment.
As for the inspection of gantry crane (height limit pole), not only the inspection method of control standard, but also the targeted inspection method according to the specific inspection content and environmental factors, so long as this can really improve the inspection degree. The inspection of gantry crane includes mechanical part inspection and electrical part inspection. There are many kinds of inspection methods for mechanical parts, including the detection of camber in the span of main beam and the detection of warpage in the web of main beam.
The inspection method for the camber of the main beam in the span of the gantry crane is as follows: the main beam is leveled with the cushion frame, and the elevation of the upper cover plate at the base plates at both ends is ≤ 2mm. In case of double girder structure, the cushion frame shall be placed under the main girder base plate; in case of single girder structure, the center line of the cushion frame support shall be placed 700mm outside the main girder base plate.
In addition, the maintenance grounding of gantry crane is inspected. On the one hand, it is required to check whether the metal structure of tower crane is well connected with the shell of electrical equipment; on the other hand, check whether the zero line is repeatedly grounded. If the measured repeated grounding resistance is ≤ 10, the tower body buried in the air can be repeatedly grounded. Otherwise, independent grounding body shall be set for repeated grounding.
Not only that, but also check whether the total current circuit of gantry crane tower crane has short circuit maintenance and installation, whether the selection and setting meet the rules, record the rated current of fuse or the action setting current of breaker; calculate or quantitatively test the phase zero circuit impedance, and calculate the single-phase short circuit current.
