Experts working on the first draft of a new best practice guide on the safe use, inspection and maintenance of rope sheaves on mobile cranes hope to have it available for discussion during ESTA’s autumn meetings in Copenhagen this October.
The project was set up by ESTA together with FEM, the European Association of Lifting Equipment Manufacturers, using the same three-strong expert team that produced ESTA’s recently published document on winch gearboxes.
ESTA had received comments from members expressing concern about the correct use, inspection and maintenance issues with sheaves that it felt merited further study.
The expert team driving the project comprises Klaus Meissner from ESTA, Gerrit van Hove from Sarens and Hermen Kamp from Mammoet.
They are bringing together different stakeholders, including sheave and crane manufacturers along with end users.
The goal is a consensus document supported by all parties, which will provide best practices for inspection and maintenance. When complete the guide will be published by ESTA on its website.
The first draft will be discussed by representatives of ESTA and FEM at the next meeting of the joint European regulations Working Group in Copenhagen on October 23.
Klaus Meissner said: “Typically, sheaves are not neglected but the effects if a sheave would fail are often underestimated.
“Users are uncertain what happens over time, for example with plastic materials, and how to check the function of bearings. It is also often not understood that not every grease is a good choice for a roller bearing.”
He added: “When we carried out the work on winch gearboxes, we were delighted to received support and valuable input from multiple manufacturers right along the supply chain.
“We very much hope that the same will apply to this project and that we can pool all of our different skills and knowledge for the benefit of the industry as a whole.”
Rope sheaves on mobile cranes are pulley-like wheels with grooves around their circumference, designed to guide wire ropes or cables, and they serve a critical function in the crane’s lifting mechanism by holding the load and often being the luffing mechanism of the crane boom.
They also ensure that the wire rope follows a controlled and efficient path between the boom, winch drum, and hook block, without contact to fixed parts, reducing abrasion and fatigue on the rope, so extending its life and helping to ensure safety.
But without effective inspection and maintenance, the sheave could become dangerously unstable – an issue that is of concern to ESTA members.