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Handling precautions for synthetic man-made ropes and hawsers

Precautions for synthetic man-made ropes and hawsers

Although natural fibre ropes are still widely used throughout the marine industry, they have been superseded by synthetic fibres for a great many purposes. Not only do the majority of synthetic ropes have greater strength than their natural fibre counterparts, but they are more easily obtainable and at present considerably cheaper.

Ropes may be of a right-hand lay or left-hand lay, but the most common is right-handed. It is essential to realise that each of the components is turned (twisted) up in an opposite direction to that of its predecessor, e.g. in right-hand lay, strands are laid up right-handed (clockwise), yarns laid up left-handed, and fibres laid up right-handed.

Mooring ropes

Fig: Mooring ropes used on board


Handling precautions

1. The mariner should carefully inspect a rope, both internally and externally, before it is used. Man-made fibre ropes show deterioration after excessive wear by a high degree of powdering between the strands.

2. Ropes should be kept out of direct sunlight. When not in use, they should be covered by canvas or other shield, or, if the vessel is engaged on long sea passages, stowed away.

3. When putting a splice in a synthetic fibre rope, use four full tucks, followed by two tapered tucks (strands halved and quartered).The length of the protruding tails from the completed splice should be left at least three rope diameters in length.Any tail ends of strands should be sealed by tape or similar adhesives.

4. A stopper should be of the same material as that of the rope being stoppered off, and should preferably be of the ‘West Country’ type. The one notable exception to this rule is that a nylon stopper should never be applied to a nylon (polyamide) rope.

5. A minimum number of turns should be used when heaving manmade fibre ropes about winch barrels or capstans. Friction-generated heat should be avoided, and to this end no more than three turns should be used on drums.Where whelped drums are being used, it may be necessary to increase the number of turns so as to allow the rope to grip; if this is the case, then these turns should be removed as soon as possible.

6. Never surge on man-made fibre rope. Should it be required to ease the weight off the rope, walk back the barrel or drum end, as when coming back to a stopper.

7. When making fast to bitts,make two round turns about the leading post, or two turns about both posts, before figure-eighting .





Safe handling of man-made fibre ropes requires techniques which differ from those for handling natural fibre ropes. Man-made fibre ropes are relatively stronger than those of natural fibre and so for any given breaking strain have appreciably smaller circumferences, but wear or damage will diminish strength to a greater extent than would the same amount of wear or damage on a natural fibre rope.

Polypropylene ropes

Polypropylene fibres make low-cost, all-purpose ropes. They are light and float, making them suitable as rescue or short mooring lines. However, the ropes have a low resistance to abrasion and sunlight.

Polypropylene ropes

Fig: Polypropylene ropes


Polypropylene ropes come in a number of forms.They are probably the most popular of the man-made fibres at sea.The ropes are cheap, light to handle, have the same strength whether wet or dry, and they float.They are used extensively for mooring ropes and running rigging. The melting point is low compared to nylon, 165°C. Friction-generated heat should be avoided with this man-made fibre, which is extremely susceptible to melting and fusing. Should the fibres fuse together, the rope is permanently damaged and weakened.

It is resistant to chemical attack by acids, alkalis and oils, but solvents and bleaching agents may cause deterioration. It neither absorbs nor retains water, and because of this fact has recently been used for the inner core of wire ropes,the advantage being that inner corrosion in the wire is eliminated. However, the wire would still need to be lubricated externally. Fibrefilm, a by-product from polypropylene, is a very cheap version of the fibre. It is produced from continuous thin twisted polypropylene tape, and used for general lashing purposes.


Ropes may be of a right-hand lay or left-hand lay, but the most common is right-handed. It is essential to realise that each of the components is turned (twisted) up in an opposite direction to that of its predecessor, e.g. in right-hand lay, strands are laid up right-handed (clockwise), yarns laid up left-handed, and fibres laid up right-handed.

Rope should be inspected internally and externally before use for signs of deterioration, undue wear or damage.


Polyester ropes and hawsers

A heavy rope compared to the nylon and not as strong, but nevertheless some of the polyester’s properties make it a worthwhile rope to have aboard. It is considered to be more resistant to acids, oils and organic solvents than its nylon counterpart, while its strength remains the same whether in a dry or wet condition. It is used for mooring tails and mooring ropes. Its disadvantages are very similar to nylon’s. It will not float. Splices must have four full tucks and may draw more easily than with a natural fibre rope when under stress. It should not be surged on drum ends. Frictional heat should be kept to a minimum when working about bitts or warping drums.The melting point is between 230° and 250°C.


Ropes may be of a right-hand lay or left-hand lay, but the most common is right-handed. It is essential to realise that each of the components is turned (twisted) up in an opposite direction to that of its predecessor, e.g. in right-hand lay, strands are laid up right-handed (clockwise), yarns laid up left-handed, and fibres laid up right-handed.

Rope should be inspected internally and externally before use for signs of deterioration, undue wear or damage.

Nylon ropes

This is the strongest of all the man-made fibre ropes. It has good elasticity, stretching up to 30 per cent and returning to its original length. It is used for such functions as shock-absorbing when coupled with a mooring wire: the nylon forms a rope tail which takes the heavy shocks as a vessel ranges on her moorings. It is also used in a combination tow line – one section steel wire and one section nylon rope.

Nylon ropes are light to handle, twice as strong as an equivalent sized manilla and give the appearance of a smooth slippery surface. They are impervious to water, have a high melting point, 250°C, and in normal temperature are pliable, being suitable for most forms of rigging.

The disadvantages of nylon ropes are that they do not float, and in cold climates they tend to stiffen up and become difficult to handle. They should not be left exposed to strong sunlight or be stowed on hot deck surfaces, as their natural life will be impaired. The significant point with these ropes is that they are used when great stress occurs. Should they part under such stress, there is a tendency for them to act like elastic bands, an extremely dangerous condition to be allowed to develop.The nylon rope will give no audible warning when about to part; however, when under excessive stress, the size of the rope will considerably reduce.They are difficult to render on a set of bitts, and should never be allowed to surge.Any splices in the nylon ropes will tend to draw more easily than in natural fibre when under stress. Nylon is expensive, but its life may be considered to be five times as long as its manilla equivalent.

Ropes may be of a right-hand lay or left-hand lay, but the most common is right-handed. It is essential to realise that each of the components is turned (twisted) up in an opposite direction to that of its predecessor, e.g. in right-hand lay, strands are laid up right-handed (clockwise), yarns laid up left-handed, and fibres laid up right-handed.

Rope should be inspected internally and externally before use for signs of deterioration, undue wear or damage.


Rope splice guideline

The method of making eye splices in ropes of man-made fibres should be chosen according to the material of the rope.

(i) Polyamide (nylon) and polyester fibre ropes need four full tucks in the splice each with the completed strands of the rope followed by two tapered tucks for which the strands are halved and quartered for one tuck each respectively. The length of the splicing tail from the finished splice should be equal to at least three rope diameters. The portions of the splice containing the tucks with the reduced number of filaments should be securely wrapped with adhesive tape or other suitable material.

(ii) Polypropylene ropes should have at least three but not more than four full tucks in the splice. The protruding spliced tails should be equal to three rope diameters at least.

(iii) Polythene ropes should have four full tucks in the splice with protruding tails of three rope diameters at least.

Mechanical fastenings should not be used in lieu of splices on man- made fibre ropes because strands may be damaged during application of the mechanical fastening and the grip of the fastenings may be much affected by slight unavoidable fluctuations in the diameter of the strands.

Man-made fibre stoppers of like material (but not polyamide) should be used on man-made fibre mooring lines, preferably using the `West Country' method (double and reverse stoppering).

All Ropes should be inspected internally and externally before use for signs of deterioration, undue wear or damage.


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