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Grade 80 QOF Chain Sling is a quad-leg lifting assembly manufactured from quenched and tempered Grade 80 alloy steel chain and components. The sling is equipped with a quad oblong master link assembly on the top and Grade 80 forged hooks on the bottom, making it suitable for heavy-duty lifting operations requiring multiple lifting points and balanced load distribution.
The quad-leg configuration helps improve load stability and distribute lifting forces across four chain legs, making it ideal for handling large machinery, fabricated steel structures, precast concrete components, and industrial equipment. The forged hooks are manufactured from Grade 80 alloy steel and provide reliable engagement with lifting points while maintaining compatibility with Grade 80 lifting systems.
Q = Quad Leg
O = Quad Oblong Master Link Assembly
F = Forged Hook
QOF therefore refers to a Quad Leg Chain Sling fitted with a Quad Oblong Master Link Assembly on the top and Forged Hooks on the bottom.
Each sling is permanently identified with:
Individual Serial Number
Chain Size
Chain Grade
Exact Sling Length
Working Load Limit (WLL)
The serial number on the identification tag corresponds with the production certificate and sales order record, ensuring complete product traceability throughout the product life cycle.
Heavy Machinery Handling
Structural Steel Lifting
Precast Concrete Installation
Equipment Installation
Mining Maintenance
Industrial Material Handling
All chain slings are supplied with written certification and manufactured using matching Grade 80 components to ensure compatibility throughout the lifting assembly.
Meter table
| Diameter of Lifting Chain | 1 Leg | 2 Legs | 3 & 4 Legs | Continuous Sling | ||
| ![]() | ![]() | ![]() | |||
| 0<a<45° | 45°<a<60° | 0<a<45° | 45°<a<60° | |||
| Factor 1.0 | Factor 1.4 | Factor 1.0 | Factor 2.1 | Factor 1.5 | Factor 1.6 | |
| (mm) | (ton) | (ton) | (ton) | (ton) | (ton) | (ton) |
| 4 | 0.5 | 0.71 | 0.5 | 1.06 | 0.75 | 0.8 |
| 5 | 0.8 | 1.12 | 0.8 | 1.6 | 1.18 | 1.24 |
| 6 | 1.12 | 1.6 | 1.12 | 2.36 | 1.7 | 1.8 |
| 7 | 1.5 | 2.12 | 1.5 | 3.15 | 2.24 | 2.5 |
| 8 | 2 | 2.8 | 2 | 4.25 | 3 | 3.15 |
| 10 | 3.15 | 4.25 | 3.15 | 6.7 | 4.75 | 5 |
| 13 | 5.3 | 7.5 | 5.3 | 11.2 | 8 | 8.5 |
| 16 | 8 | 11.2 | 8 | 17 | 11.8 | 12.5 |
| 18 | 10 | 14 | 10 | 21 | 15 | 16 |
| 19 | 11.2 | 16 | 11.2 | 23.5 | 16.8 | 17.9 |
| 20 | 12.5 | 17 | 12.5 | 26.2 | 18.7 | 20 |
| 22 | 15 | 21.2 | 15 | 31.5 | 22.5 | 24 |
| 26 | 21.2 | 30 | 21.2 | 44.5 | 31.8 | 33.9 |
| 28 | 25 | 33.5 | 25 | 52.5 | 37.5 | 40 |
| 30 | 28 | 39.2 | 28 | 58.8 | 42 | 44.8 |
| 32 | 31.5 | 45 | 31.5 | 66.1 | 47.2 | 50.4 |
| 36 | 40 | 56 | 40 | 84 | 60 | 64 |
| 38 | 45 | 63 | 45 | 94.5 | 67.5 | 72 |
| 40 | 50 | 70 | 50 | 105 | 75 | 80 |
| 45 | 63 | 88.2 | 63 | 132.3 | 94.5 | 100.8 |
| 50 | 78.5 | 109.9 | 78.5 | 164.8 | 117.7 | 125.6 |
Continuous Sling
Working Load Limit (WLL) for an endless chain sling configuration.
0° < a < 45°
The angle between the sling leg and the vertical is between 0° and 45°.
45° < a < 60°
The angle between the sling leg and the vertical is between 45° and 60°.
Factor
The load multiplier used to calculate the Working Load Limit for different sling configurations and lifting angles.
a
The angle between the sling leg and the vertical line.
(ton)
All values are expressed in metric tons and represent the maximum Working Load Limit (WLL).
Feet table
| Design Factor | 1-Leg Sling | 2-Leg Sling | 3-Leg & 4-Leg Slings | ||||
| 4:01 | ![]() | ![]() | ![]() | ||||
| Chain Diameter | 90 Degrees | 60 Degrees | 45 Degrees | 30 Degrees | 60 Degrees | 45 Degrees | 30 Degrees |
| Load Factor: 1 | Load Factor: 1.7 | Load Factor: 1.4 | Load Factor: 1 | Load Factor: 2.6 | Load Factor: 2.1 | Load Factor: 1.45 | |
| 7/32″ | 2,100 | 3,600 | 3,000 | 2,100 | 5,500 | 4,400 | 3,200 |
| 9/32″ | 3,500 | 6,100 | 4,900 | 3,500 | 9,100 | 7,400 | 5,200 |
| 5/16″ | 4,500 | 7,800 | 6,400 | 4,500 | 11,700 | 9,500 | 6,800 |
| 3/8″ | 7,100 | 12,300 | 10,000 | 7,100 | 18,400 | 15,100 | 10,600 |
| 1/2″ | 12,000 | 20,800 | 17,000 | 12,000 | 31,200 | 25,500 | 18,000 |
| 5/8″ | 18,100 | 31,300 | 25,600 | 18,100 | 47,000 | 38,400 | 27,100 |
| 3/4″ | 28,300 | 49,000 | 40,000 | 28,300 | 73,500 | 60,000 | 42,400 |
| 7/8″ | 34,200 | 59,200 | 48,400 | 34,200 | 88,900 | 72,500 | 51,300 |
| 1″ | 47,700 | 82,600 | 67,400 | 47,700 | 123,900 | 101,200 | 71,500 |
| 1-1/4″ | 72,300 | 125,200 | 102,200 | 72,300 | 187,800 | 153,400 | 108,500 |
Design Factor 4:1
The minimum breaking force of the sling assembly is at least 4 times its Working Load Limit (WLL).
90 Degrees
The sling is lifting vertically with no sling angle reduction.
60 Degrees / 45 Degrees / 30 Degrees
The angle between each sling leg and the horizontal plane. As the angle decreases, the sling capacity decreases.
Load Factor
A multiplier used to calculate the Working Load Limit based on the number of sling legs and the lifting angle.
WLL Values (lbs)
The numbers shown in the table represent the maximum Working Load Limit in pounds for each chain diameter and sling configuration.
Example:
For a 1/2" chain sling:
1-Leg Sling = 12,000 lbs
2-Leg Sling at 60° = 20,800 lbs
2-Leg Sling at 45° = 17,000 lbs
2-Leg Sling at 30° = 12,000 lbs
3 & 4-Leg Sling at 60° = 31,200 lbs
3 & 4-Leg Sling at 45° = 25,500 lbs
3 & 4-Leg Sling at 30° = 18,000 lbs
Note: The lifting angle shown in this table is measured from the horizontal. Smaller angles result in higher tension in each sling leg and lower overall lifting capacity.
Name: Grade 80 QOF Chain Sling – Quad Leg w/ Quad Oblong Master Link on Top and Forged Hooks on Bottom
MOQ: 100 Sets
Package: Carton + Steel Pallet
Manufacturing Standards: Manufactured from Grade 80 quenched and tempered alloy steel chain and components in accordance with EN 818-2, EN 1677-1, EN 1677-2, EN 1677-4, ASME B30.9, OSHA 1910.184, AS 2321, and ISO 3077 requirements for lifting chain sling assemblies.
Testing Standards: Manufactured with a minimum design factor of 4:1. Each sling is proof tested, visually inspected, dimensionally verified, and checked for component compatibility before shipment. The chain complies with EN 818 fatigue requirements and successfully withstands 20,000 cycles at 1.5 times the Working Load Limit (WLL). Every sling is supplied with an individual serial number, identification tag, written certification, and full traceability records.
Application Standards: Suitable for overhead lifting, multi-point lifting, heavy machinery handling, structural steel erection, precast concrete installation, equipment installation, mining maintenance, and industrial material handling operations.
Maintenance Standards: Inspect before each use for chain elongation, excessive wear, cracks, corrosion, forged hook deformation, damaged master links, connecting links, and missing identification tags. Remove the sling from service immediately if defects exceed the applicable inspection criteria.