Differences in Size, Construction, Lay, Core, Grade, Finish
Understanding the basics of wire rope will help guide you on how to choose the right wire rope for your job. Application, required strength, and environmental conditions all play a factor in determining the type of wire rope that is best for you.
But when it comes to buying wire rope, the various numbers and abbreviations that describe the different types of wire rope can be confusing. EIPS wire rope, 6X19 IWRC wire rope, and lang lay wire rope are just some of the many variations available. But what does it all mean?
These wire rope basics will help you understand the differences among types of wire so you can buy with confidence.
Displayed as inch or fractional inch measurements, the size indicates the diameter of the rope. Industry standards measure the rope at its widest point. A wide range of sizes are available from 1/8” wire rope to 2-1/2” wire rope. Thicker sized wire rope has a higher break strength. For example, our 3/8” 6X19 IWRC Galvanized Wire Rope has a 15,100 lb. break strength while our 1-1/2” 6X19 IWRC Galvanized Wire Rope has a 228,000 lb. break strength.
Wire rope is composed of individual wires that are twisted to form strands. The strands are then twisted to form a rope construction.
The numbers indicate its construction. For example: in 6X19 wire rope, as shown at left, the first number is the number of strands (6); the second number is how many wires make up one strand (19).
Numbers may also be followed by a letter combination such as FW or WS which indicates how the outside layer is constructed.
FW= filler wire (same sizes throughout)
WS= Warrington Seale (combination of large and small)
Refers to the direction the wires and strands are twisted during the construction of the rope.
When it comes to wire rope, regular lay is also referred to as right lay or ordinary lay. This indicates that the strands pass from left to right across the rope and the wires in the rope are laid in opposite direction to the lay of the strands. This type of construction is the most common and offers the widest range of applications for the rope.
This term indicates that the wires are twisted in the same direction as the strands. These ropes are generally more flexible and have increased wearing surface per wire than right lay ropes. Because the outside wires lie at an angle to the rope’s axis, internal stress is reduced making it more resistant to fatigue from bending. This type of rope is often used in construction, excavating, and mining applications.
Refers to what makes up the center of the wire rope.
FC= fiber core
Fiber cores are made of vegetable (sisal, etc.) or synthetic (polypropylene, etc.) fiber and offer more elasticity.
IWRC= independent wire rope core
Independent wire rope cores offer more support to the outer strands and have a higher resistance to crushing and heat. Independent wire rope core also has less stretch and more strength.
Refers to the grade of steel used. Classifications include:
IPS= improved plowed steel.
EIPS = extra improved plowed steel (approximately 10% stronger than IPS).
EEIPS= extra extra improved plowed steel (approximately 10% stronger than the EIPS).
GIPS= galvanized improved plowed steel; galvanized wires add corrosion resistance.
DGEIP= drawn galvanized improved plow steel; galvanized for corrosion resistance. Drawn wires generally have a higher break load than GIPS.
This last tip on wire rope basics refers to the protective coating applied to the wire rope.
Made with uncoated wires manufactured from high carbon steel.
Provides extra corrosion resistance.
Highly resistant to corrosion and is commonly used in marine applications.