GB/T 5976-2006 Wire Rope Clips Standard Guide
Scope of Application and Positioning
Wire rope clips covered by GB/T 5976-2006 consist of three components: a U-bolt, a clip body, and a nut. The U-bolt presses the wire rope against the clip body, generating friction force to transmit tensile load. The standard specifies dimensions for wire rope diameters ranging from 6 mm to 60 mm.
The clip body is made of Q235B or Q345B steel, while the U-bolt is manufactured from 45 steel or 40Cr. All surfaces are hot-dip galvanized for anti-rust protection. After assembly, the clip body and U-bolt must rotate freely, and the U-bolt threads must be complete and free from damage.
Installation Method and Inspection Requirements
The standard provides detailed installation guidelines for wire rope clips — the U-bolt must be placed on the dead end (non-load-bearing side) of the rope, with the clip body on the live end. Clips should be spaced evenly at approximately 6 to 7 times the wire rope diameter. The distance from the rope end to the last clip must be at least 150 mm. During installation, tighten the nuts with preload until the rope is compressed to about one-third of its original diameter, then apply the rated load and re-tighten to the specified torque. The U-bolt threads must extend at least two full turns beyond the nut.
Clips must never be installed in reverse. The quality of wire rope clip installation directly affects the reliability of rope-end fixing, and the following principles must be followed: the U-bolt should be on the dead end (non-load-bearing side), with the clip body on the live end. Clip spacing should be uniform, approximately 6 to 7 times the wire rope diameter. The distance from the rope end to the last clip must be ≥150 mm.
During installation, first tighten the nuts with preload until the rope is compressed to roughly one-third of its original diameter, then apply the rated load to further compress the rope, and finally re-tighten to the specified torque. After tightening, the U-bolt threads must protrude at least two full turns beyond the nut. Reverse installation (placing the U-bolt on the load-bearing side) can cause the rope to slip out of the clip body under load — this is one of the most common causes of rope slippage accidents.
All clips on the same rope end should be arranged in the correct orientation in sequence. After installation, a safety loop should be created at the rope end (bend the rope end back and secure it with a second clip) to prevent accidental slippage and injury. The scribe-line marking method involves drawing a continuous straight line across the U-bolt head and clip body after installation — any thread loosening will cause the line to misalign, making it immediately visible.
| Wire Rope Diameter(mm) | Clamp Seat Specification | Number of Clamp Seats | Torque(N·m) | Spacing(mm) |
|---|---|---|---|---|
| 6~16 | Y-6~16 | ≥3 | 25~120 | 48~112 |
| 16~25 | Y-18~25 | ≥4 | 120~200 | 108~175 |
| 25~32 | Y-25~32 | ≥5 | 200~300 | 175~224 |
| 32~40 | Y-32~40 | ≥6 | 300~400 | 224~280 |
Inspection and Test Requirements
Per the standard, each batch of wire rope clips must undergo visual inspection (U-bolt deformation, saddle cracks, surface treatment quality) and dimensional inspection (specification fit). Periodic inspection of tightening status is required during service—the scribe-line marking method is the most practical way to detect bolt loosening. A wire rope clip must be scrapped if any of the following occurs: U-bolt deformation or thread damage, saddle cracks (even hairline cracks are unacceptable), or severe corrosion resulting in a cross-section reduction exceeding 20%.
The standard recommends against reusing wire rope clips; they should be scrapped and replaced after removal. Each batch must also undergo visual inspection (U-bolt deformation, saddle cracks, surface treatment quality) and dimensional inspection (specification fit). U-bolts require a hardness test—45 steel quenched and tempered to HRC28~32, or 40Cr quenched and tempered to HRC32~36.
The saddle material must be verified to ensure it is Q235B (≈S235JR) or Q345B (≈S355J2). Each finished clip must be individually checked for fit clearance between the U-bolt and saddle, as well as rotational flexibility. During service, the tightening status of clips should be checked at least once a month. The scribe-line marking method is the most practical approach for detecting bolt loosening, allowing for quick visual inspection without the need for torque-wrench checks on each bolt.
A wire rope clip must be scrapped under the following conditions: U-bolt deformation or thread damage, saddle cracks (even hairline cracks are unacceptable), severe corrosion causing a cross-section reduction exceeding 20%, or wire rope slippage beyond the specified limit after installation. The standard advises against reusing clips—discard and replace them after removal. Kelude Heavy Industry offers a full range of wire rope clips as supporting supply.
| inspection items | technical requirements | Cycle | Judgment |
|---|---|---|---|
| Visual inspection | None Crack/Corrosion | Per Batch | Conforming |
| Dimension Inspection | Specification Matching | Batch | Conforming |
| installationinspection | UShort Form Lock End | Per Batch | Correct |
| Tightening Torque | M8~M20 | after installation | Reach Torque |
Wire Rope Clip FAQ: Installation, Torque & Inspection
Q: What are the required number and spacing of wire rope clips?
A: For wire rope diameters under 16 mm, use at least 3 clips; 16–25 mm, at least 4; 25–32 mm, at least 5; and 32–40 mm, at least 6. Clip spacing should be approximately 6 to 7 times the wire rope diameter. The distance from the rope end to the last clip must be at least 150 mm. The U-bolt should be placed on the short (non-load-bearing) end of the rope, with the clip saddle on the load-bearing side.
Q: What are the tightening torque values and inspection intervals for wire rope clips?
A: Apply approximately 25 N·m for M8, 40 N·m for M10, 60 N·m for M12, 120 N·m for M16, and 200 N·m for M20 bolts. Re-tighten after the initial load is applied, as the rope compresses and reduces in diameter. Inspect bolt tightness weekly; marking a reference line across the bolt and clip is the most practical way to detect loosening.
Q: What are the discard criteria for wire rope clips?
A: Discard clips if the U-bolt is deformed or the threads are damaged, if cracks appear in the saddle, if corrosion reduces the cross-section by more than 20%, or if the rope slips beyond the specified limit after installation. Wire rope clips are not intended for reuse — replace them with new ones once removed.
Q: How do wire rope clips compare to other end fastening methods?
A: Wire rope clips are easy to install, require no special tools, and allow readjustment, making them suitable for temporary on-site fastening. Wedge sockets offer a more reliable hold but require a matching wedge. Clamp plate fixing is the most secure option but requires a grooved drum. Aluminum sleeve swaging provides the most permanent connection but demands a specialized crimping tool.
