Whether you need a sling assembly or any other product for an overhead lifting application, we know that you’re always looking for the best the industry has to offer. At Pacific Rigging Loft, Inc. we are proud to have been one of the most trusted suppliers of wire rope, rigging hardware, slings, and other lifting products in the industry, for decades.
What is Wire Rope?
Wire rope has a unique design consisting of steel wires that form individual strands laid in a helical pattern around a center core. Wire ropes are widely used in many applications such as crane, tower crane, surface and underground mining, excavation, logging of any type of terrain, tramway, elevator, oil and gas, drilling, marine and electrical constructions.
Wire rope is a complex mechanical device that has many moving parts all working in tandem to help support and move an object or load. In the lifting and rigging industries, it is attached to a crane or hoist and fitted with swivels, shackles or hooks to attach to a load and move it in a controlled matter. It can also be used to lift and lower elevators, or as a means of support for suspension bridges or towers.
Wire rope is a preferred lifting device for many reasons. Its structure provides strength, flexibility, and the ability to handle bending stresses. Different configurations of the material, wire, and strand structure will provide different benefits for the specific lifting application, including:
- Abrasion resistance
- Crushing resistance
- Fatigue resistance
- Corrosion resistance
- Rotation resistance
However, selecting the proper wire rope for your lifting application requires some careful thought. Our goal is to help you understand the components of a wire rope, its construction, and the different types of wire rope and what they might be used for. This will allow you to select the best performing and longest-lasting one for the job at hand.
Advantages of using a Wire Rope:
It has the advantage of being an affordable, durable, and versatile option when planning a heavy lift. They’re available in a variety of lengths, which makes them perfect for deep drilling, mining, and construction projects. The strength of this type of rope resides in twisting multiple stands of wire to form one thicker rope. While flaws in chain links or solid steel bars can lead to catastrophic failure, flaws in the wires making up a steel cable are less critical as the other wires easily take up the load. Friction between the individual wires and strands, as a consequence of their twist, further compensates for any flaws.
What are the different types of Wire Ropes?
Differentiate types of wire rope according to the following factors: grade, wire type, strand construction, core, and lay.
Wire rope grades refer to their strength. The three main grades, listed from most durable to least, are: improved plow steel, mild plow steel and plow steel. The strongest grade of wire rope, improved plow steel, is also the least pliable. The least strong, plow steel, is the most pliable.
The three main types of wire comprising wire rope are: bright wire, galvanized wire and stainless steel wire. Bright wire composed of uncoated high-carbon steel is the most common. Galvanized wire is coated in zinc to add enhanced corrosion resistance. Stainless steel wire offers the highest corrosion resistance.
Wire rope strand construction refers to the size of the individual wires comprising the rope. Large diameter wires better resist abrasion while smaller diameter wires are more flexible. The four most common types of wire rope strand construction are: ordinary, scale, filler and Warrington. Ordinary strand rope contains wires that are all of uniform size. Scale rope contains wires with a larger diameter on the outside and smaller diameter on the inside, closer to the core. Warrington rope contains alternating large and small wires for a combination of flexibility and abrasion resistance. In filler rope, smaller wires fill in the gaps between the larger wires.
Wire rope cores support the strands coiled around them. The three types of wire rope cores are: fiber, wire strand and independent wire rope. Fiber is the most flexible and may include materials like paper, plastic, sisal or manila. Wire strand cores are more heat resistant and about 15 percent stronger than fiber cores, but less flexible. The strongest and most heat resistant is independent wire rope, which has a separate wire rope laid over the main strands.
The lay of wire rope represents the directions in which the wires twist in each strand and in which the strands lay around the core. The five types of wire rope lays are: right and left regular lay, right and left lang lay and reverse lay. In regular lay, the strands all lay to the left while the differentiation of right and left refers to the direction of the wires in the strand. In lang lay, the strands and wires run in the same direction, with right and left delineations indicating that direction. In reverse lay, the strands all lay to the right while their wires alternate direction from one strand to the next.