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Marble & Granite

Cost-effective Material Handling for the Marble and Granite Industry

Gentle handling and accurate positioning are extremely important when you work with expensive and highly brittle raw materials. At times, the use of air handling systems makes positioning slabs easier, and sophisticated below-the-hook devices (such as vacuums) aid in the process as well. But cost-effective material handling begins with a quality lifting system, and North American cranes are ideal for your precise application.

Our mechanical braking system on the trolley and bridge eliminates the need to adjust brakes on a regular basis (typically every 3 months). There are no brake pads to change or adjust with our mechanical brakes. This will reduce overall maintenance and extend the life of the wheel gears and pinions.

We use a minimum of 2 bearings per wheel. All of our bearings are Class "D" which means they are designed with a minimum life expectancy of 10,000 hours of actual motor on-time. This is double the Class "C" rating - bearings for Class “C” cranes have a minimum life expectancy of 5,000 hours. Our Class "D" bearings are also sealed-for-life and never need lubricating.

Our contactors, rated for 20,000,000 stop / start cycles if used in conjunction with electronic soft start features, should never need replacing under normal operating conditions. Click here for our Technical Report on electrical contactors.

For maximum control, we also offer infinitely variable speed controls, which allow the movement of the hoist, trolley and / or end trucks to be precisely regulated by the operator from 1% to 100% of the main speed, and any speed in between. With this option, the load is lifted or moved at precisely the desired speed--very slow for precise positioning, moderate speed for cluttered areas, or full speed for efficiency.

In addition to improved "positioning", variable speed invertors offer other significant advantages:

  • Dramatically reduce wear on brakes (15-fold), by eliminating quick, repetitive starts;
  • Reduce wear / Extend life of gear motors and couplings; and
  • Eliminate contactors.

Finally, North American's concrete and stone dust package keeps the electrical controls and motors of your crane safe from the effects of airborne particles through the use of totally enclosed motors and gasketed control boxes.

North American’s design capabilities go far beyond this simple list, however. Our team of engineers can custom-design for the most demanding and complex applications; no matter what your requirements, NAI expertise can improve your productivity and add value to your operation.

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