BS EN ISO 09554:2010 pdf free download – Fibre ropes – General specifications (ISO 9554:2010).
C.2.5 Knotting
The practice of knotting eyes into ropes, or knotting ropes to shorten them, should be avoided. Knots may weaken ropes by up to 50 %.
C.2.6 Kinking and hockling
Excessive turns can cause kinking in any rope but hockles (see Figure Cl) only occur in basic twisted (laid) ropes. Braided and plaited ropes cannot be hockled as their interlocking strand construction prevents unlaying. Strands run in both directions creating a torque-free balance, thus eliminating any inherent tendency towards twist or rotation.
Excessive turns (kinking) in a rope should be removed by “counter rotating” the rope in a relaxed condition as soon as possible. Once the hockles are formed, the rope has lost breaking strength, even when the hockle has been unlaid. The damage is irreversible and the loss of strength could be as high as 30 %.
Kinks should never be allowed to form in the rope (see Figure C.5). If kinks do form, this is a sign that turn has been gained or lost in the rope, and the kinks should be taken out of the rope from one end. This recommendation applies equally to laid and braided ropes.
Kinks are especially serious with laid ropes, as serious damage can result if attention is not paid to them. Attempts to eliminate kinking should never involve pulling the rope in an attempt to force the kink out. The result might be to cause the strand to distort as shown in Figure C.6.
If cyclic loading continues, the hockle will run until the rope has once again reached a position of torsional balance but, clearly, the defect makes the rope unusable.
C.2.7 Snapback safety warning
A dangerous situation occurs if personnel are in line with a rope under excessive tension. Should the rope fail, it will likely recoil with considerable force. Death might result. Persons should be warned against standing in line with the rope or in its bight.
C.3 Limitations on the use of fibre ropes due to environmental conditions or hazardous applications
The following are aspects to be considered when using rope for special applications:
a) selective material resistance to chemicals;
b) restrictions due to temperature; c) susceptibility to cutting and abrasion; d) degradation due to ultraviolet radiation.
Before each period of use, refer to the rejection criteria in Table C.1.
C.4 Periodic thorough examination and maintenance
The following are aspects to be considered regarding examination and maintenance:
a) retirement criteria, including missing/damaged label and illegible marking;
b) records of examination.
C.5 Fibre rope inspection and retirement criteria
C.5.1 Inspection of cordage
C.5.1.1 General
Before a length of rope is issued for use, the entire length, including eye splices and/or long splices, should be inspected by a competent person. This examination should be undertaken to look for the types of damage described in C.5.1 .2 to C.5.1 .8.
C.5.1.2 External wear
Some types of ropes will develop a fur or pile on their surface as the result of dragging over rough surface. This is quite normal and will not cause weakening of the rope to any significant extent. Excessive wear is indicated by a major portion of the cross-sections of the yarns on the outside of the rope being removed. Such wear is usually seen most clearly on the strand crowns and on the inside of eye splices, in particular underneath a rope thimble, if incorporated (see Figure C.9).