Install the steel wire rope in a correct way for safe use and to not damage your product. In this article you find advise on how to uncoil the steel wire rope from the packaging, advice on how to connect and running-in the new rope and how to cut the steel wire rope if necessary.
The procedure for installing the rope should be carried out in accordance with a detailed plan issued by the user of the steel wire rope. The as-manufactured condition of the rope should be maintained during installation.
Note! When releasing the outboard end of the rope from the supply reel or coil, this should be done in a controlled manner. On release of the bindings or the rope end fixing, the rope will want to straighten itself and unless controlled this could be a violent action, which could result in injury.
Rope supplied in a coil
The coil of rope should be placed on the ground and rolled out straight, ensuring that it does not become contaminated with dust, grit, moisture or other harmful material.
The rope should never be pulled away from a stationary coil as this will induce turn into the rope and form kinks. If the coil is too large to physically handle it may need to be placed on a turntable which will allow the rope to be paid out as the end of the rope is pulled away from the coil.
Figure 1 and figure 2 shows the correct methods of paying out rope from a coil. Figure 3 shows an incorrect method of paying out rope from a coil and how the kinks occur.
Rope supplied on a reel
A shaft of adequate strength should be passed through the reel bore and the reel places in a suitable stand which allows it to rotate and be braked to avoid overrun during installation.
Where multi-layer coiling is involved the rope should be placed in equipment that has the capability of providing a back tension in the rope as it is being transferred from the supply reel to the drum. This is to ensure that the underlying laps of rope, particularly in the bottom layer, are wound tightly on the drum. Recommended load is about 10% of the ropes nominal load.
The supply reel should be positioned such that the fleet angle during installation is kept to a minimum, max. 1.5 °. This can be done by placing the supply reel and its supporting stand or cradle as far away from the drum as possible. If a loop forms in the rope it should not be allowed to tighten to form a kink.
The reel stand should be mounted so as not to create a reverse bend during reeving (S-shape), see figure. Ie. for a drum with an upper wind rope, take the rope off the top of the supply reel.
Note! The supply reel is not specifically designed for back-tension spooling and might not be strong enough! If back tension spooling is needed, a reel of enough strength should be ordered with the steel wire rope.
When spooling should be done to the crane drum without back tension, the hook should be lowered max, a sufficient weight (2,5% -5% of the ropes MBL) should be hooked and the steel wire rope could be tightly wound on the drum.
If installing the new rope with the aid of the old rope, one method is to fit a wire rope sock to each of the rope ends to be attached. The open end of the sock should be securely attached to the rope by a serving or alternatively by a suitable clip or with a welded eye.
It is important to reduce the risk of turn being transmitted from the old rope into the new rope, especially when replacing rotation resistant ropes. This can be done by connecting the ropes with a fiber rope, alternatively the coupling or wire rope sock can be equipped with a swivel, which enables individual rotation between the ropes.
Note! We do not recommend to connect the new and the old rope by welding. This can cause turn to transmit from the old to the new rope and the welding can break, for example when passing through sheaves.
Alternatively, a length of fibre or steel rope of adequate strength may be reeved into the system for use as a pilot/messenger rope. If a steel wire rope is used, it should be a rotation resistant rope or have the same rope lay as the new rope.
Note! The rope used as a coupling or pilot rope needs to have sufficient strength to withstand the new steel wire rope's own weight and any stress during installation.
Running in the new rope
To increase lifetime of your rope its recommended to ‘run in’ the new rope by operating the equipment slowly, preferably with a low load (i.e. 10% of the Working Load Limit (WLL)) for several operational cycles. This enables the new rope to adjust itself gradually to the working conditions. The rope should never 'run in' with full load or even with overload.
Check that the rope is spooling correctly on the drum and that no slack occurs in the rope or cross-laps of rope develop at the drum.
Note! Irregular coiling will inevitably result in severe surface wear and rope distortion
Cutting the rope
Usually ropes are supplied in cut lengths, with "tapered" ends made by annealing. If the rope is required to be cut before installation, secure servings should be applied on both sides of the cut mark. This is made to prevent damage from opening strands and/or changing lay length.
One serving either side of the cut mark is usually enough for preformed (standard) ropes. For non-preformed ropes, rotation resistant ropes and parallel-closed ropes a minimum of two servings each side of the cut mark is recommended. The length of each serving for a stranded rope should be at least equal to 2 x rope diameter.
Cutting should be made with a high speed abrasive disc cutter, cutting torch or other suitable mechanical or hydraulic shearing equipment. When cutting, ensure adequate ventilation to avoid any build-up of fumes from the rope and its constituent parts.
Note! Some special ropes contain synthetic material which, when heated to a temperature higher than normal production processing temperatures, will decompose and may give off toxic fumes.
Note! Rope produced from carbon steel wires in the form as shipped is not considered a health hazard. During subsequent processing (e.g. cutting, welding, grinding, cleaning) dust and fumes may be produced which contain elements that may affect exposed persons.
After the rope has been cut the seizing should be left until all the wires are welded or otherwise secured. After cutting, failure to correctly secure the rope end is likely to lead to slackness or distortions in the rope. An alternative method of cutting is by fusing and tapering, a process which is designed to prevent the wires and strands from unlaying.