STEEL ROPE LIFTING RODS
TECHNICAL SPECIFICATIONS OF STEEL ROPE TIE RODS
These lifting slings can be made with slots (inside which thimbles can be inserted to protect them from wear) or with lifting accessories including:
Aluminum alloy sleeves pressed with special molds.
With hand splicing, that is, with the interweaving of the strands that make up the rope and the disappearance of the same in staggered steps.
With recomposed loops, dividing the end of the rope, recomposing the two halves opposite each other and closing the ends with pressed conical sleeves.
Continuous steel wire rope rings, highly flexible and suitable for high loads without having to opt for a larger nominal diameter of the rope at the connection point.
EEC directives 91/368 require that all lifting equipment must be equipped with appropriate plates (metallic or plastic) showing:
> Manufacturer's name and brand
> The scope
> The length
> Number of arms
> The certificate number
All this information must always be reported on the certificate of conformity issued upon delivery to the customer.
CAPACITY OF STEEL ROPE TIE RODS WITH TEXTILE CORE
Use and Maintenance of Steel Wire Ropes and Steel Wire Rope Slings
What follows is a brief summary of the basic information required to safely use steel wire ropes and steel wire rope slings.
Nominal Strength
A steel wire rope will fail if it is worn, overloaded, improperly used, damaged, or not properly maintained. In service, a steel wire rope loses strength and working capacity. Abuse and improper use accelerate this loss.
The nominal strength of a steel wire rope applies only to a new, unused rope. The nominal strength should be considered as the straight-line pull that will actually break a new, unused rope. The nominal strength of a steel wire rope should never be used as the working load limit.
Working Load
To determine the working load of a steel wire rope, the nominal strength must be reduced by a design factor. The design factor will vary depending on the type of machine and installation, and on the work being performed. It is necessary to determine the design factor applicable to your specific use.
For example, a design factor of “5” means that the nominal strength of the steel wire rope must be divided by five to determine the maximum load that can be applied to the rope system. Design factors have been established by CEN, OSHA, ANSI, ASME, and similar governmental and industrial organizations. No steel wire rope or steel wire rope sling should ever be installed or used without full knowledge and consideration of the design factor for the application.
Reduction of Working Load
Steel wire ropes wear over time. Rope strength begins to decrease as soon as the rope is put into service and continues to decrease with each use. Never overload a steel wire rope. This means never using the rope with a load greater than the working load.
Never “shock load” a steel wire rope. A sudden application of force or load can cause visible external damage as well as internal damage. There is no practical way to estimate the force applied by shock loading a rope. The sudden release of a load can also damage a steel wire rope.
Inspection and Maintenance
Lubricant is applied to the wires and strands of a steel wire rope or steel wire rope sling during manufacture. This lubricant is depleted when the rope is in service and should be periodically replaced. Regular and periodic inspections of the steel wire rope, along with the maintenance of permanent records signed by a qualified person, are required for almost all steel wire rope installations.
The purpose of inspection is to determine whether a steel wire rope or steel wire rope sling can continue to be safely used for that application. Inspection criteria—including the number and location of broken wires, wear, and elongation—have been established by CEN, OSHA, ANSI, ASME, and similar organizations. When in doubt, replace the rope.
An inspection should include verification that none of the removal criteria specified for that application are met, checking for example:
Surface wear: normal and abnormal
Broken wires: number and location
Reduction in diameter
Rope elongation
LOAD CAPACITY OF STEEL ROPE TIE RODS WITH METAL CORE
TABLE OF CAPACITIES AND SAFETY COEFFICIENTS
FOUR-ARM STEEL ROPE TIE ROD
