Lay of Ropes and hawsers used on board a general cargo vessel




Defining lay of ropes


The lay of rope is a term used to describe the nature of the twist that produces the complete rope.The purpose of alternate twisting of fibres, yarns and strands is to prevent the rope becoming unlayed when in use.

Z laid and S laid or braided ropes
Fig:Right hand or left hand laid ropes

The majority of ropes are manufactured with a right-hand lay, but lefthand laid ropes are available. The most common form of rope at sea is known as ‘hawser laid rope’ comprising three strands laid up right- or lefthanded. Other types of lay include ‘cable lay’, made of three or four hawsers laid up left-handed, and sometimes referred to as water lay, which is strictly incorrect. ‘Water lay’ was a rope designed to be used when wet, e.g. sounding line. Consequently it was laid up in the course of manufacture in a wet condition, so allowing for shrinkage in use. Cablelaid ropes, although generally left-handed lay, may be encountered as right-hand lay (left-hand hawsers being used) but these are extremely rare.


Eight Strand Plaited

Many mooring ropes used at sea today are ‘eight strand plaited’, constructed by laying two pairs of strands left-handed, with the other two pairs right-handed.This type of lay has the advantages that it does not kink and also, with eight strands, has increased flexibility.However, it is difficult to splice, and the manufacturers’ instructions should be consulted.


Shroud Lay

Another type of lay found at sea is ‘shroud lay’ , consisting of four strands, sometimes being laid about a central heart, right-handed. As the name implies, it was used for standing rigging (the shrouds to the mast) until wire ropes came into use.


Soft-Laid

Often referred to as a long lay, soft-laid is a strong flexible method of laying up a rope.The angle of the strand to the axis through the centre of the rope is comparatively small. It will absorb water more easily and will not be as hard-wearing for example as a hard-laid rope.The ‘jaw’ of the lay is large with a soft-laid rope.


Hard-Laid

Sometimes called short lay, when the ‘jaw’ of the lay is small in comparison to a soft-laid rope, hard-laid is harder wearing than the former, does not easily absorb water and tends to retain its shape better when under stress. Being hard in construction, it is not very flexible, and its breaking stress and subsequent safe working load are inferior to those of soft or standard laid ropes.


Standard or Plain-Laid

Standard lay may be described as a cross between hard- and soft-laid ropes. It has been found by experience to be the best in providing pliability and strength, and to be sufficiently hard-wearing and chafe-resistant to suit the industry for general purpose working.


Sennet-Laid

Alternatively known as plaited, but not as in the way as the ‘eight strand plaited’ previously mentioned, an example of sennet lay is found with the patent log line, where the yarns are interwoven, often about a centre heart. This lay of rope has an effective anti-twist, non-rotational property.


Unkinkable Lay

This lay looks like standard lay, but close inspection will reveal that the yarns are twisted the same way as the strands. Left-handed in construction, it is usually ordered for a specific job, e.g. gangway falls.The advantage of this lay is that the tendency for standard lay to kink when passing through a block is eliminated.


Small Stuff

Small stuff is a collective term used at sea with respect to small cordage usually less than 38 mm (11/2 in.) in circumference and of 12 mm diameter approximately.


Hambroline (hamber line)

Also known as codline, this is supplied in hanks of about 30 fathoms. It is made of soft tarred hemp, three yarn or three-stranded, laid up righthanded. It is manufactured in two sizes, three or six threads, and is used for Many natural fibre products such as ‘Ratline’ and ‘Hambroline’ have been phased out of common use with modern ship designs and have been superseded by man-made fibre substitutes. lashings where strength is essential, usually an untarred variety having a hard lay.


Houseline

Manufactured from Indian hemp, houseline is made of three yarns laid up left-handed. It is tarred and sold in balls by weight and often used to secure bolt rope to sails.


Boat Lacing

Manufactured in fourteen various sizes, it is made of a high grade dressed hemp, having a fine finish and being smooth to handle. Before the invention of man-made fibre, it was used for securing boat covers, awnings etc. It is sold in hanks weighing from 93 g to 1.8 kg.


Marline

Marline is usually supplied in hanks by weight, tarred or untarred. It is made in two ply, i.e.two yarns laid up left-handed, from better quality fibres than spunyarn, and produces a much neater, tighter finish to any job. It is used for seizings, serving and whipping heavy duty ropes.


Spunyarn

Made from any cheap fibres and turned into yarns, spunyarn may have two, three or four yarns, usually laid up left-handed. The yarns are supposed to be soaked in Stockholm tar, for spunyarn is used for the serving of wires, and the idea was that in hot climates the lubricant (Stockholm tar) would not run from the serving. Spunyarn is generally sold in balls of up to 3.2 kg or in coils of 6.4 kg or 25.6 kg by length or weight.


Point Line

A three-stranded manilla rope, point line is made and may be ordered in three sizes, which are determined by the number of threads: Circumference 13/8 in (35 mm) diameter 11 mm 15 threads. Circumference 11/2 in (38 mm) diameter 12 mm 18 threads. Circumference 15/8 in (41 mm) diameter 13 mm 21 threads. It is used as an all-purpose lashing aboard most present vessels. Sisal very often replaces manilla in so-called point line.


Ratline

This is one of the family of tarred cordage, measured the same as point line, except that the number of threads may be as high as twenty-four (circ. 13/4 in.) (45 mm). It was used in the past for steps between the shrouds of a Many of the natural fibre ropes have become obsolete with expansion in the man made rope sector of the industry. The loss of rigging aboard the modern vessel has also speeded up its demise. If seen on a modern vessel, it will probably be encountered as a heaving line. Supplied in coils of 120 fathoms, it is made of three-stranded soft hemp, hawser lay.


Logline (Virtually Obsolete)

Logline is made of sennet-laid hemp (plaited), specially for the towing of the rotator (patent log), and comes in 40, 50, 65, or 70 fathom coils.The size will vary from about 3/4 in. to 11/2 in. (6–12 mm diameter).The woven line is kink proof, very durable and sometimes built up about a copper wire core.


Lead Line

Made of high grade cable-laid hemp, it may be obtained in a size of 11/8 in. (9 mm diameter) for hand lead lines. It is supplied in 30 fathom coils for the hand lead.


Seaming Twine

Manufactured from the best flax, this three-ply twine is made up in hanks of approximately 1 lb weight and 900 fathoms length. It is used extensively for canvas work.


Roping Twine

This five-ply twine is supplied in hanks of similar length and weight to that of seaming twine. It is used for whipping the ends of ropes,worming etc.


Signal Halyard

Often spelt halliard, this used to be three- or four-stranded dressed hemp, but this natural fibre has given way to man-made fibres such as polypropylene. It may be supplied in a variety of sizes to the customer’s requirements. Plaited laid halliards are predominant on the modern merchant vessel, being preferred because the stretch is not as great as, say, hawser lay.The word halyard was derived from the old-fashioned ‘haul yard’, which was previously employed on sailing vessels to trim and set the sails to the yard arms.

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



Related info:


Natural fibre rope

Synthetic fibre ropes





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