The chain’s initial rod is supplied by steel mills. The rod will be cleaned and pulled into precisely the right size of wire before being stored by the chain-making sections. Chains are made using compact machinery cells that include formers, welders, calibrators, and sporadically twisters. The grade and trace code is stamped onto the wire after the former has roughly cut it to the length required for a chain connection. This part is wire-formed into a link, which combines with the first link that has already been created to make a chain. The chain with each link’s termination is given to the welder, who then forges the links. The chain’s tensile strength is also evaluated throughout this process, with particular attention paid to the welded section.
Welded chain samples are taken from the production run numerous times per shift in order to assess the weld’s structural integrity and physical attributes. Electronic records of each test’s results are kept for further reference. Certain chains are twisted to be used in cross chains for tire chains that come into touch with the road. The chain is inspected before being put into a storage box to await the next step. All Uq customers as well as the chain’s grade must have an impact on the process. We’ll send a part of the chain to our induction heat treaters for quenching and tempering, where it will be heated to between 1600 and 1700 degrees F, cooled in water, and then tempered at 400 to 600 degrees.
At that point, the chain will be automatically proof-tested to double its working load limit. These chains will be stored in drums or reduced to length before being assembled into a range of goods, mostly tow, binder, and agricultural safety chains. Please be advised that only alloy chains should be used for overhead lifting and that no chain should ever be loaded above its rated working load limit. Some chain classes, such as a proof coil or high test, don’t require heat treatment.
Contrary to popular belief, form and welding would be followed by packaging, shot blasting, hot-dip galvanizing, zinc plating, or other specialty coatings. The completed welded chain is packaged and prepped for transportation, but it will likely only be cut and assembled into a range of products.
After being delivered, the chain can either be used or sold by the customer.
