Wire Rope Sling Turn-back Eye with Mechanical Spliced separate into two type which is Soft Eye Mechanical Spliced Wire Rope Sling and Hard Eye/ Thimble Eye Mechanical Spliced Wire Rope Sling(With Thimble).
What is mechanical splicing? The mechanical splicing here refer to the process using a hydraulic wire splicing machine to press the ferrule until specified size to secure and hold the turnback eye. While for the ferrule size from 2.5 to 5 can by splice using hand tool or hand swager.
(Figure 1: Soft Eye Mechanical Spliced)
Hard Eye (With Thimble):
(Figure 2: Hard Eye Mechanical Spliced)
The function of thimble is to protect the wire rope against the abrasion in between wire rope and lifting hardware or equipment at the bearing point.
To prepare for the soft eye, turnback length of wire rope need to be calculated as in Figure 3 by follow the EN13411-3. While for the hard eye or thimble eye, the turnback length need follow the thimble.
(Figure 3: Diagram of Soft Eye Eye Length )
The h is the eye length of sling, it is equal to 15 multiply by nominal diameter of wire rope.
Size and specification of ferrule:
For Wire Rope Grade 1960 TS, only standard length and long length ferrule can be accepted according to EN13411-3. Short length ferrule can only use up to Grade 1770 TS wire rope. Please check the ferrule type before use as if short type ferrule being used on Grade 1960 TS wire rope, the Safe Working Load(SWL) need to conform to Grade 1770 TS working load which is lower with same diameter and same type of core of wire rope as efficiency lose using short type ferrule on Grade 1960 TS wire rope.
Here are the step and precausion you need to know before pressing the ferrule:
1. After pressing of the ferrule the fins shall be removed for safety purposes during handling.
2. Do not press the fins back into the ferrule.
3. If the fins generated is thick and difficult to remove, the mould might have excessive wear, hence the condition of the mould needs to be assessed.
4. The contact and inner surfaces of the mould shall be clean and lubricated with grease to reduce wear and tear and easy to remove the pressed ferrule from the mould.
5. The pressing tools have to be parallel..
Chart Below shows the ferrule size and its compatible wire rope size, and the size of ferrule after splicing conforming to EN13411-3:
Chart 1: Chart of Wire Rope Diameter and its compatible ferrule size
Chart 2: Chart of Standard Length Aluminium Ferrule Dimension EN13411-3 / DIN 3093 Before Press
Chart 3: Chart of Standard Length Aluminium Ferrule Dimension EN13411-3 / DIN 3093 After Press (conform to EN 13411-3)
The temperature limits of wire rope sling with a fibre core is – 40 °C to + 100 °C
The temperature limits of wire rope sling with a steel core is – 40 °C to + 150 °C
Exceed the maximum temperature or below the minimum temperature, the Safe Working Load of the Wire Rope Sling will decrease