Problems with Contact Interruptions One of the most frustrating problems that a crane operator can experience is when there are contact interruptions between the conductor bars and the collector. Tese contact interruptions can cause intermittent control problems with the overhead crane system. On the collector, a brush made from carbon graphite can

wear down, which can cause carbon graphite to build up. Because carbon graphite dust is a conductive material, this build up can cause shorts in the electrical connection. On older crane systems, the copper rails on the conductor bars can also become corroded or oxidized due to the operating environment or due to long periods where the crane is not being used. To prevent this from happening, the conductor bars and collectors should be inspected and cleaned regularly to make sure that the contact between the collector and conductor bar is uninterrupted. Another problem that can cause contact interruptions

is if there are alignment issues with the conductor bars themselves, causing the collector shoes to jump out of the track and lose contact.

Problems with Push Button Pendants or Radio Controls Although not very common, there are environments that create their own radio waves that may interfere with the operation of an overhead crane. An example might be a facility that performs induction heating or induction welding procedures. Radio waves created during these processes may disrupt the communication between the radio’s transmitter and receiver. On pendant controls and radio controls, the push buttons

or levers may stick or become unresponsive over time. Te control may need to be replaced or repaired to correct any issues with the operation of the buttons. You may also find that pendant controls can become disconnected or pulled out of the hoist. Te reason that this can occur is because the operator pulls on the pendant to maneuver or position the crane—especially on jib or workstation cranes. If your controls become unresponsive, you may need to check to see if the pendant became disconnected from the hoist, or have the system serviced and re-wired if any wires become loose.

Blown Fuses If you find that your overhead crane is blowing fuses, then it’s an indication that you have a faulty circuit in the crane’s electrification system. Contact a crane service provider immediately to come out and inspect the crane’s electrification system and identify the fault.

5. BENT OR DAMAGED HOOKS A hook is designed to hold a load in a particular and precise direction. When the weight isn’t supported as intended by


the hook, it compromises the internal integrity of the hook and can increase the chance of it bending, stretching, or cracking. Te load can also slip off of the hook if it stretches out the throat opening. Regular inspection of hooks and other pieces of rigging

hardware should be performed at the beginning of each shift to check for deformities or damage. While there are no clear-cut guidelines on the use of hook latches, we train our employees and inspectors that if a hook is designed to have a latch, it should have the latch installed to help move a load safely and securely. We advise that the end user must evaluate the work activity with regards to the safety of their employees. If the activity makes the use of the latch impractical, unnecessary, or more dangerous, then the end user may choose to eliminate the latch. It is also recommended that each lifting activity is considered independently as far as the use of a hook latch is concerned.

Help Protect Your Overhead Crane from Excessive Wear and Costly Downtime To help prolong the life of an overhead crane system, there are a number of things that should be taken into consideration before you even buy an overhead crane:

Make sure your crane is rated for the actual duty cycle and usage required. Be honest with yourself and the manufacturer who is designing and building your overhead crane. Don’t try to design or build a crane that won’t meet the actual usage and duty cycle requirements of your business. Every component on the crane is rated for a specific load capacity – if your crane isn’t built to handle your actual lifting needs, it can lead to premature wear or failure.

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