The diameter of rope is the diameter of its circumference. To obtain the practical diameter, the average of two points at least one meter apart and two diameters measured at 90 Degrees from the other is taken when the rope is not under tension.

STRANDS are the simplest constructions, consisting of one or more layers of superimposed wires laid spirally around one or more central wires or around a fibre core. The construction of the strand is identified by the number of wires in the individual layers starting from the outer one like 12+6+1. Strands are of two types: Cross- laid and equal-laid.

A.	Strands with Cross Laid Wires All the wires in this type of strand are of equal diameter and each layer of wire is laid up a separate operation with a different length of lay resulting in the crossing of the various layers of wires. Consequently strong pressure occurs between the wires, which may break especially with variable loads.
B.	Strands with Equal Laid Wires The pitches of the various layers of wires are identical as stranding is carried out in a single operation. Therefore, the contacts between wires are linear. Seale, Warrington and Filler strands belong to this construction. Wires of different diameters are required for these constructions

ROPES consist of a number of strands either laid around a fibre core [jute(FC) or polypropylene (PP)] or metallic core [Wire Strand Core (WSC) or an Independent Wire Rope Core (IWRC)]. A rope with 6 strands of 9+9+1 wires laid around a central fibre is designated as 6x(9+9+1)+FC, more concisely 6x19 Seale+FC. 7x7 or 7X(6+1) would indicate a metallic (IWRC) core. Should the strands also contain a fibre core then the rope will be know for example as 6x(6+FC)+FC or 6x6+7FC.

Lastly if the rope is formed of two or more layers of strands superimposed around a FC, then it will be known as: 12x[(6+1)+6x(6+1)]+FC or 18 x 7 FC.

Lay has three meanings in rope design. The first two meanings are descriptive of the wire and strand positions in the rope. The third meaning is a length measurement.

1.	The direction of the strands in the rope — right or left. When you look down a rope, strands of a right lay rope go away from you to the right. Left lay is the opposite. (It doesn’t matter which direction you look.)
2.	The relationship between the direction of the strands in the rope and the direction of the wires in the strands. In appearance, wires in Ordinary (Regular) Lay run straight down the length of the rope, and in Lang’s Lay, they appear to angle across the rope. In Ordinary lay, wires are laid in the strand opposite the direction the strands lay in the rope. In Lang’s lay, the wires are laid the same direction in the strand as the strands lay in the rope.
3.	The length along the rope that a strand makes one complete spiral around the rope core. This is a measurement frequently used in wire rope inspection.

The lay of a rope affects its operational characteristics. Ordinary Lay is more stable and more resistant to crushing than Lang’s Lay. While Lang’s Lay is more fatigue resistant and abrasion resistant, use is normally limited to single layer spooling and when the loads are restrained from rotation like passenger and freight elevators because wires have a longer contact with the sheave grooves thereby undergoing less wear. Given equal construction and diameter, Lang’s Lay ropes are more flexible than Ordinary Lay ropes. The wire ropes we manufacture are preformed according to special methods which give them stability and eliminate internal stresses.

Wire ropes are lubricated as a protection against oxidization and to reduce frictions between wires and strands. Fibre cores are impregnated and during the stranding and roping operations, all wires forming the strand and all strands forming the rope are lubricated. The type of lubrication varies according to the application for the rope and the type of use for which it is intended. During the working life of the rope, lubrication should be carried out periodically with lubricants compatible with those used during manufacture. Lubricants used during manufacture are free from solvents, moisture, aromatic compounds, alkaline soaps and acidity both organic and inorganic. The lubricants we use for engineering applications is wax based and for fishing ropes cadmium compound is used which is bituminous based.

The core of a wire rope is the central member around which the main strands are laid to support the strands and maintain them in their proper position when loads are applied. The two types of cores commonly used in wire ropes are metallic cores [Independent Wire Rope Cores (IWRC) & Wire Strand Cores (WSC)] and fibre cores (FC) of either natural (jute, manila or sisal) or synthetic fibres like polypropylene (PP) or polyethylene. For ropes of dia 13mm and below, WSC is generally used as the metallic core unless otherwise specified. When fibre core is specified, jute is generally used except for fishing ropes where polypropylene is used.

Galvanized ropes have their wires uniformly coated with zinc for protection against corrosion where atmospheric condition is saline or the rope is exposed to other corroding agents as well as when it is used in water. Where periodic lubrication is possible in engineering ropes, heavily lubricated bright ropes are usually preferred to galvanized ropes. Lion Brand Fishing Ropes are coated with an extra heavy coating of Zinc and heavily coated with cadmium compound.

In a preformed wire rope, the individual wires in the strands and strands composing the rope, are properly pre-shaped by a preforming head before they are assembled into the finished rope. Preforming prevents the wire and strands from straightening and leaves them relaxed in their normal positions in the rope. Preformed ropes have the following merits as compared with non-preformed ropes;

A.	Does not require seizing as they retain the rope structure.
B.	Superior flexibility compared to non-preformed ropes and wire ropes kinks scarcely ever occur during use.
C.	Longer life because preformed wire ropes have a great endurance to bending.
D.	Broken wire ends do not protrude to injure workmen’s hand, distort adjacent wires, or cause wear to sheaves and drums.

Wire Ropes are manufactured in various Tensile Grades to meet the varied requirements of many applications. Each grade provides a different combination of tensile strength, toughness, and endurance to abrasion and bending. The grades are 1230, 1420, 1570, 1770 & 1960 N/mm².

A Factor of Safety is a multiplier of the Nominal Strength to ensure the safety of the rope over its service life, by incorporating the normal rope wear and stresses that may occur in the course of general use.

Common Factors of Safety are:

Sl. No.	Type of Service	Minimum Factor of Safety
01.	Hoisting Equipment	5.0
02.	Haulage Rope	6.0
03.	Overhead & Gantry Cranes	6.0
04.	Jib & Piller Cranes	6.0
05.	Derricks	6.0
06.	Small Electric and Air Hoists	7.0
07.	Hot Ladle Cranes	8.0
08.	Hot Ladle Cranes	3.5
09.	Wire Rope Slings	5.0
10.	Mine Shafts Depths to 500 ft Depths of 500 – 1000 ft Depths of 1000 – 2000 ft Depths of 2000 – 3000 ft Depths of 3000 or more	8.0 7.0 6.0 5.0 4.0

Types of ropes for various applications are listed below. The operating conditions, including the design and construction of the installation affect the service life of the wire rope.

General Engineering Rope	6 X 19, 6 X 21, 6 X 25, 6 X 36, 6 X 37 Groups
Earth Moving Equipment	6 X 21, 6 X 24, 6 X 25, 6 X 36, 8 X 31, 7 X 19, 7 X 37 Groups
Logging	6 X 19, 6 X 21, 6 X 25, 6 X 31 Groups
Shipping	6 X 12, 6 X 19, 6 X 24, 6 X 25, 6 X 36, 6 X 37, 7 X 7, 7 X 19, 8 X 31 Groups
Oil Industry	6 X 19, 6 X 21, 6 X 25, 6 X 26, 6 X 31, 6 X 37 Groups
Mining Industry	6 X 7, 6 X 19, 6 X 21, 6 X 25, 6 X 27 Groups

Ropes should be stored in a clean dry place under cover. Reels or coils should be kept off the ground and supported by timber. They should also be examined periodically and rope dressing renewed as required.

A.

Unreeling and Uncoiling Reels should be mounted on jacks and care taken to see that the reel rotates as the rope unwinds. Timber should be applied as a lever to one of the flanges to act as a brake, keeping the rope tight and preventing the reel from over-running. When the ropes are supplied in coils a turntable should be employed and the free end pulled out with even tension as the turntable revolves. Over-winding should be avoided at all times to avoid kinking. Coils may also be unwound by securing the free outside end of the rope and then rolling the coil along the ground; care being taken at all times to ensure that the coil is held firmly together, avoiding tight coils or kinks.

B.

Seizings It is important that before cutting ropes are properly seized with annealed mild steel wire or strand to avoid slack wires and possible rope distortion.

Wire ropes can be discarded if the following conditions are noticed, as failure may occur much below the ultimate tensile strength.

Wear & Tear	Internal – Wear & Tear of wires within strand and between strands External – Scrubbing of wire rope against external surfaces and due to low drum speed
Corrosion	Loss of metal due to corrosive environment
Fatigue	Repeated reversal of stress leads to brittle fracture of wires
External Deformation	Presence of Corkscrew formation, Cage Formation, Looping of Wires or strands, knots, construction, flattening, curling, puffing & kinks
Action of Heat	Excessive heat dried out ropes leading to risk of internal wire rupture
Type, Position & Number of Wire Ruptures	Wire ruptures in nests or strand break
Abnormal Stretching	Paralleling of the strand due to untwisting of the rope
Surface Embrittlement	Work hardening of the wire surface leading to fatigue failure
Core collapse	Non-circular wire rope shape
Fitting Time	Expected rope life from previous experience
Accidental Damage

To avoid errors it is necessary, when asking for quotations or placing orders, that the required rope be accurately specified.

Please state the following data when sending enquiries or orders:

1.	Please state the following data when sending enquiries or orders:
2.	Ungalvanized or galvanized: (ex. Galvanized)
3.	Diameter or circumference: (ex. 25 mm
4.	Direction and type of lay: (ex. Right-Hand Ordinary Lay
5.	Preformed or non-preformed: (ex. Preformed)
6.	Lubrication: (ex. Cadmium compound)
7.	Tensile Strength : (ex. 180 Kgs/mm2 )
8.	Specification: (ex. ISI, BSS. API, DIN etc.)
9.	Packing: (ex. Coil, Wooden-drum etc.)
10.	Usage: (ex. Fishing, Sky-line, Haul-back line & etc.)

If parts of these data are not stated, the rope will be supplied in the nearest current type. It is therefore, recommended always to state the service for which the rope is intended.

BREAKING LOAD AND MASS FOR 8 X 19 (9/9/1) CONSTRUCTION

Nominal Diameter	Approximate Mass	Minimum Breaking Load Corresponding to Tensile Designation of Wires of
		1230	1420	1570
MM	Kg/100 m	KN	KN	KN
8	22.3	23	26	29
9	28.2	29	33	37
10	34.8	35	41	45
11	42.2	43	49	55
12	50.2	51	59	65
13	58.9	60	69	76
14	68.3	69	80	88
16	89.2	90	104	115
18	113	114	132	146
19	126	127	147	163
20	139	141	163	180