WIRE ROPE SLING | GENERAL INFORMATION
Strong Wire Rope Sling, Synthetic Fiber Ropes & Polypropylene Multifilament Rope Supplier: Malaysia, Singapore, Thailand
As a supplier of lifting slings in Singapore, Malaysia and Thailand, we understand that Wire Rope Sling and Synthetic Fiber Ropes are very famous in the construction industry. Our Wire Rope Sling is approved by the ministry in many countries and had been proven for its quality. Aside from that, our Synthetic Fiber Ropes particularly the Polypropylene Multifilament Rope is also a better replacement for manila ropes. In addition to this, Top Slings’ Synthetic Fiber Ropes particularly the Polypropylene Multifilament Rope are also suitable as ropes for cable railings or as other interior design element. Our lifting slings products can be purchased through our specialist in Singapore, Malaysia and Thailand.
1. Construction of wire rope
The design of a rope is determined by
STRAND CONSTRUCTION (The number and arrangement of wires in each strand)
ROPE CONSTRUCTION (The number and arrangement of strands in each rope)
2. Wire Rope Lay
right hand: Clockwise
regular lay: Counter-clockwise
– Wires in strands are laid in the opposite direction of the strands and are parallel to the rope axis.
– Ropes with regular lay are easy to handle and have greater resistance to crushing than those with lang lay.
– Wires are laid in the same direction as the strands of the rope, and in an angle to the rope axis.
– Longer lengths of the individual wires are exposed, creating greater resistance to wear and improved flexibility.
– Lang lay ropes should only be used where both rope ends are “fixed”and therefore, should not be used with a swivel type terminal.
3. Cores of wire ropes
IWRC(Independent Wire Rope Core)
The main core is an independent wire rope,normally having the construction 7X7, 7X17(S)
IWSC(Independent Wire Strand Core)
The main core is an independent wire strand,normally having the same construction as the outer strands of the rope.
Fibre cores are stranded and comprised either :
Natural fibres such as sisal, hemp, jute, and cotton.
Synthetic fibres such as polyimide, polyethylene, and polypropylene.
4. Preformed ropes
In the preforming process the wires and strands are given their final helical pitch before being laid up into rope. Ropes made in this way show no tendency to untwist when cut.
Lubrication reduces internal friction of the wires and strands and protects against corrosion. Grease is applied to all ropes. If special lubricants are required this must be specifically stated at time of ordering.
6. Diameter of wire ropes
The diameter of a wire rope is the diameter of the circle which encloses all of the wires. When measuring wire rope it is important to take the greatest distance of the outer limits of the ‘Crowns’ of two opposite strands. A measurement across the valleys will result in incorrect lower readings.
7. Sheave and Drum
When a rope is bent around the sheave or drum, individual wires in the strand are subjected to bending stress and repeated bending fatigue. To obtain a smooth operation and longer life for the wire rope line, it is necessary to keep the diameter of sheave and drum above the recommendable figures of the Table and to keep the surface of the grooves sharp and smooth.
8. Safety factor of wire rope
It is difficult to fix the safety factor for each type of wire rope to be used for various equipment, as this factor depends not only on the load carried, but also on the speed of rope working, the kinds of fitting used for rope ends, the acceleration and deacceleration, length of rope, the number, size and arrangements of sheave and drums etc. The following safety factors are minimum requirements for safety and economy in the common installation.
9. Must avoid for longer life for wire rope
- Twist, Loop or Kink of wire rope.
- Moisture, Dust and Acid or Sulphuric Hume gas.
- Crushing or hammering.
- Severe or reverse bending(S-Bending).
- Too small Sheaves, Drums and Guide Rollers.
- Hard rolling or Sheaves and Rollers.
- Worn Groove, Broken or Soft Sheaves and Rollers.
- Poor or No Lubrication.
- Heat Influence.
- Wrong Fitting and Spooling on the Drum.
- Excessive Fleet Angle.
- Obstacles, Sand and Grit on the surface of operation line.
- Shock-Too fast start or Stop.