Suspension clamps are used to hang conductor or ground wire through insulators or link fitting to tower ams or substation struetures. The clamps are made of mall eable iron or aluminium alloy.Suspention clamp hangs conductor or ground wire. They work with the insulator of link fitting to tower arms or substation structures. The material of clamp is malleable iron or aluminum alloy. The suspension angle of suspension clamps is not less than 25 degree. The redius of curve is not less than 8 times the diameter of the installed leads. The percentage of the grip on different kinds of leads to the calculating capicity of snap meets the international standard.
Table of Contents
- What is suspension clamp
- function of suspension clamp
- Type of Suspension Clamp
- Choose of Suspension Clamp
What is suspension clamp
The suspention clamp is a kind of fixed hardware. There are also two types of suspension hardware. They include tension fittings and limited grip hardware. The suspension clamp hangs or supports the conductors. They coould bear the vertical load hardware.
function of suspension clamp
The suspension clamp is for overhead lines or substations. They can hang the conductors or arresters on the insulators. They could hang the arresters on the tower by the connectors as well. It also used for fixing and supporting the conductor and non-linear rod on the pole.
As the suspension clamps are used to AAC and ACSR, the conductor may be wound by aluminum tapes or preformed armour rods for protecting these taps or rods are included in the diameter of suitable conductor.
Type of Suspension Clamp
Suspemsion Clamps (Trunnion Type)
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||
| H | L | R | |||
| 5.0-7.0 | 82 | 180 | 4.0 | 40 | 1.4 |
| 7.1-13.0 | 82 | 200 | 7.0 | 1.8 | |
| 13.1-21.0 | 102 | 220 | 11.0 | 2.0 | |
| 21.1-26.0 | 110 | 250 | 13.5 | 3.0 | |
Suspemsion Clamps (with socket-clevis eye)
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||
| H | L | R | |||
| 23.0-33.0 | 157 | 300 | 17 | 70 | 5.7 |
| 34.0-45.0 | 163 | 300 | 23 | 6.1 | |
Suspemsion Clamps (with u-type clevis)
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||
| H | L | R | |||
| 23.0-33.0 | 137 | 300 | 17 | 70 | 5.4 |
| 34.0-45.0 | 143 | 300 | 23 | 5.8 | |
| 45.0-48.7 | 146 | 300 | 26 | 5.4 | |
Suspemsion Clamps (type XGT)
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||||
| H | C | M | R | L | |||
| 5.0-7.0 | 60 | 18 | 18 | 4.0 | 180 | 40 | 3.3 |
| 7.1-13.0 | 75 | 18 | 18 | 7.0 | 200 | 4.9 | |
| 13.1-21.0 | 75 | 27 | 16 | 11.0 | 220 | 5.6 | |
| 21.1-26.0 | 75 | 27 | 16 | 13.5 | 250 | 60 | 6.5 |
| 23.0-33.0 | 81 | 38 | 16 | 17.0 | 300 | 8.7 | |
| 34.0-45.0 | 89 | 46 | 16 | 23.0 | 300 | 9.8 | |
Suspemsion Clamps
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||||
| H | C | M | R | L | |||
| 13.0-18.0 | 133 | 18 | 16 | 9 | 380 | 70 | 8.0 |
| 22.0-31.0 | 193 | 26 | 24 | 16 | 400 | 125 | 13.0 |
| 31.0-43.0 | 232 | 44 | 30 | 22 | 500 | 200 | 20.0 |
| 33.0-39.0 | 187 | 24 | 22 | 20 | 390 | 100 | 12.4 |
| 36.0-43.0 | 202 | 26 | 24 | 22 | 500 | 120 | 14.5 |
Suspemsion Clamps for 500kV Line
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||||
| C | M | h | R | L | |||
| 24-33 | 34 | 16 | 68 | 17 | 700 | 70 | 3.55 |
| 35-44 | 48 | 18 | 70 | 22 | 300 | 100 | 4.6 |
| 35-44 | 48 | 22 | 71 | 22 | 300 | 120 | 4.7 |
| 35-44 | 48 | 24 | 72 | 22 | 300 | 150 | 4.9 |
Suspemsion Clamps for Twin Conductors
| Applicable Conductor (mm) | Dimmensions(mm) | Rated Failure Load (kN) | Weight (kg) | ||||
| h | L | R | C | H | |||
| 21-26 | 400 | 250 | 13.5 | 20 | 490 | 70 | 9.3 |
| 23-33 | 400 | 300 | 17.0 | 38 | 490 | 100 | 10.8 |
| 34-45 | 400 | 300 | 23.0 | 38 | 490 | 100 | 12.5 |
Suspemsion Clamps for Jumper Conductors
| Applicable Conductor (mm) | Dimmensions(mm) | Weight (kg) | ||||
| L | L1 | L2 | b | b1 | ||
| 20.8-24.0 | 450 | 240 | 165 | 10 | 16 | 8.6 |
| 24.6-28.0 | 450 | 240 | 165 | 10 | 16 | 8.6 |
| 20.8-24.0 | 450 | 240 | 175 | 10 | 16 | 6.6 |
| 24.0-28.0 | 450 | 240 | 175 | 10 | 16 | 6.6 |
Choose of Suspension Clamp
Select on types and structure
The suspension clamp shoud able to bear the full load of the wire when hanging the wires.
The wire cannot slide in the clamp or get out of the insulator string. This is because the system is in normal operation or broken.
When hanging the lighting protection line, the suspension clamp can support the whole load of the lighting protection line within the vertical span.
The lighting protection wire is not allowed to slide in the wire clip when the tension is unbalance.
Suspension Clamp Should have Enough Mechenical Strength
Suspended clamps could bear the combined load. The loads contains vertical and horizontal loads of conductors or lightning conductors.
The majority load of the conductor or lightning protection line may occur. After considering the safety factor, it should not be less than or equal to the failure load of the wire clamp.
Majority load is the comprehensive value of the self-weight, ice-covered weight and horizontal wind load of the guide line or lightning protection line. The national standard is the safety factor of mechanical strength. The safety factor under normal conditions is 2.5.
Suspension Clamp Should have Standard Grip Strength
Grip strength refers to the determination of the grip strength value of the clamp. The clamp on the conductor install under the specified test conditions.
The suspension clamp should have a certain grip on the wire or the lightning protection wire. The grip on the lightning protection wire have uneven icing or uneven sealing load. The sealing load is under the condition of line operation. This means the wire should not slip out of the wire clamp under such conditions.
| Type of Cable | Structure (Al Vs St) | Percentage (%) |
| Steel Core Aluminum Wre | >1.7 4.0~4.5 5.0~6.5 7.0~8.0 11.0~20.0 | 12 18 20 22 24 |
| Copper Wire Steel Wire Al. Wire | Limited Strenghth 1176~1247N/mm2 | 28 14 30 |
Suspension Clamp should have a Suitable Angle
Suspension angle:
Suspension angles of the strands on both sides of the suspension point may fluctuate. This is becuase the differences between the span and height of the tower. This difference induce by terrain variation. Another reason is the changes in the conductor and lightning protection wire due to ambient temperature and load change.
The method to avoid the damage of the stranded wire is to increase bending stress at the outlet of the clamp. Thus, a necessary check should carry out. The check ensure the actual hanging angle of the outlet on both sides of the wire clip. To make sure it meet the national standards.
National standard is the suspension angle of the suspension clamp. The angle should not be less than 250. The suspension clamp’s curvature radius should be at least 8 times the diameter of the installed wire.