Load Moment Indicator: Assuring Safe Operation of your Tower Crane

Jun 25
05:54

2007

Rajesh Karavadia

Rajesh Karavadia

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Towercranes Information and Resource

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Working with high-rise structures is as dangerous as working as a military officer in Iraq.

The risk is always present when working with high-rise structures. The transfer of construction materials from the ground up to the working floor is not as easy as you think. The pulley system that you are using must be strong and reliable to avoid any untoward accidents that may happen. In the same manner,Load Moment Indicator: Assuring Safe Operation of your Tower Crane Articles the lowering of unused construction materials from the working floor down to the ground imposes the risk of getting hit on the head. Despite of the presence of your hard hat, excessive weight could break it and can cost you your own life.

Yes, the money is on the construction industry. But is it worth the risk of losing your own life in exchange for thousands to hundreds of thousands of dollars?

This is where the heavy equipment comes in. It helps construction workers in making their task easy and safe to execute. One of the most common heavy equipment used in the construction of various structures, especially high-rise buildings, which is the tower cranes, provide such benefits to construction workers. Due to the reality of danger working on high structures, they make use of tower cranes to lift and lower construction materials with ease and at the same time ensuring safety at all times. Furthermore, most tower cranes are operated through a radio remote control system for the safety of the crane operator.

The main purpose of tower cranes is to lift and/or lower heavy construction materials. Thus, we deal here with not just kilograms of heavy construction materials, but tons of heavy construction materials. Thus, the efficiency and safety in using tower cranes to lift and lower heavy materials will depend on its stability in carrying tons of heavy load. This is where the load moment indicator comes in, and it is important for every crane operator as well as construction engineers too know what it is for and how it is beneficial to the operation of their tower cranes and the success of their construction project.

A load moment indicator is an instrument used in determining whether a rated load is stable enough to be carried by the tower crane. If you will remember, a tower crane has tow arms: the shorter arm, which carries a counterweight of heavy concrete blocks to maintain balance, and the longer arm which carries the crane’s lifting gear. Since the longer arm carries the heavy load, the shorter arm, through its counterweight, must provide an opposite force to prevent the crane from getting outbalanced when carrying heavy loads. The load moment indicator determines whether a certain load could be carried by the tower crane or not. Thus, the indicator is used to maintain the stability of the crane.

New generation of load moment indicators make use of special sensors to provide the tower crane operator with actual and correct crane working state. It indicates the moment of force applied on the crane, the hook amplitude as the height of the load increase, the crane rating, and the actual hoisting capacity of the tower crane. In case the load reached 90 percent of the crane rating at a particular moment, it will provide an early warning to the crane operator through a slow blinking red light. When the load (along with the hook amplitude) reached 105 percent, the load moment indicator will automatically trip an alarm and will stop the lifting gear from lifting the load upward.

With the load moment indicator, you are assured of a safe operation of your tower crane. Your life is important and it should not be wasted with just an excessive load capacity and wrong calculation of the actual hoisting capacity of the tower crane.