Steel ropes wear out and lose their operational properties over time, despite the large margin of safety. This process occurs gradually, so it is important to monitor the condition of the product and timely replace the rope with a new one.
Before starting work, the ropes must be inspected. It is necessary to carefully inspect and identify damage (bulging or torn strands), if any. Also, the rope should not have creases, knots and loops. The rejection of ropes, which consist of wires of the same diameter, is carried out according to the number of breaks detected during inspection at a certain length of a step, consisting of one strand. When culling, be sure to take into account breaks in strands, jams, nicks, wear and damage caused by corrosion.
Rejection for corrosion damage and wear must be made, taking into account changes in the diameter of the rope. A caliper is used to more accurately determine this parameter; a specialized precision instrument, a micrometer, is also used. The final result is compared with the characteristics that are indicated in the certificate provided by the manufacturer. We can talk about the degree of rope wear when the document indicates the wire diameter is 1 mm, and when measuring 0.8 mm, then it is considered that the rope is worn out by 20%. To determine the extent of damage, the number of wire breaks must be counted. The place on the rope with the largest number of breaks is marked with chalk. Further, in the direction where the greatest wear is located, as many strands are counted as the total number of strands in the rope (for example, 6 pieces for a six-strand rope) and a second mark is applied. On this segment, which is called the lay pitch, the number of broken steel wires is counted. In a six-strand rope, no more than 10% of broken wires are allowed, of the total number of strands in the rope. If the quantity exceeds the allowable limit, the rope is withdrawn from operation, since it is unsafe to work with it.
If other damages, such as surface wear or corrosion, are detected during the break count, the number of wire breaks is reduced. If wear or corrosion has affected the wires quite strongly, this is up to 40%, the rejection is carried out immediately, not taking into account breaks and non-compliance with the norm.
Ropes that do not meet the standard are rejected - ropes with flat sections; in the presence of a decrease or increase in diameter in some places; products with a damaged area or core; in cases where the wire has changed color in a certain area. Ropes with a visible core or several strands sticking out are also taken out of service. The rope is rejected if the strand is broken.
Only a specially trained specialist who knows the structure of various types of ropes and is able to determine the degree of wear can carry out a rope rejection. Doing such work, one should not make mistakes, the price of inattention can become very high.
You can get advice on ropes by calling us at (048) 736-04-94, (048) 736-04-84. Also in our online store www.load-tech.com.ua you can buy ropes with delivery in Ukraine.
