Pre-stretch and Heat set
With a multitude of differing constructions and manufacturing processes, making a rope can involve a complex set of processes. The balance of these processes results in a rope with the characteristics that are aligned to the end use.
A critical component of this process revolves around the twisting of the yarn. Yarn starts the manufacturing process in its strongest state when it is flat. However, in this state, the yarn also will display the poorest abrasion characteristics and is difficult to work with. Therefore, the initial stage of the majority of rope making will involve twisting yarn together to form small strands. Once this is complete the rope may either be braided (8 strand, 12 strand or cover braid) or continue to be twisted to form a 3 strand rope. The processes are designed to lay strand of yarn upon other strand with the opposite twist, thus creating a torque balanced rope.
However, once the rope is finished this is not the complete story. The fibres although balanced are straining against each other. This tension in the rope affects both the feel and the performance of the rope, especially the breaking strain. To overcome this English Braids look to heat treat the majority of product before reeling. This heat process relaxes the fibres, similar to ironing a shirt. The fibres then have no memory of the process and feel and act as a unit, thus producing a superior product.
For applications where our customers looking remove extension from the rope, the above process is undertaken with tension applied to the rope. This removes the majority of the constructional stretch from the product providing a rope with lower stretch properties. Importantly, this stretched state is maintained while the rope is not under tension producing a product that is ready for use from day 1.
For more information on the products which are subject to this treatment, please contact the sales team.