Crane Institute of America

Spliced Wire Rope Through the Grape Vine

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While vacationing, a Crane Institute Instructor visited wine country, Napa Valley, California and took a gondola, much like a ski lift, ride through the vineyard.

On cranes, hoist wire rope is one piece that can not be spliced, think of a straight line. For gondola or ski lifts, think of a circle. The two ends need to be spliced together to make a continuous piece. This type of splice is as strong as the wire rope itself.

A recent example of such splicing is when Steamboat Springs in Colorado, replaced their ski lift wire rope after 21 years and 54,000 hours of service. The wire rope of these lifts have a longer life than those installed on cranes for two main reasons. The sheaves, or bull wheels, that the rope runs on have a large D:d ratio. There is no shock loading or contact between the wire rope and other objects.

The Steamboat Springs rope was replaced with 3.4 miles of 6 x 39 plastic core wire rope, weighing 60 tons. To achieve the desired strength, the splice was 250 foot long and 10 foot of each end was hand tucked. ANSI B77-1 Passenger Ropeways Standard states that the splice length must be at least 1,200 times the diameter of the rope.

Click here to see video of the complete erection of a ski lift in Vail, CO.