Each sling is permanently identified with:

• Individual Serial Number

• Chain Size

• Chain Grade

• Exact Sling Length

• Working Load Limit (WLL)

The serial number marked on the identification tag corresponds with the production certificate and sales order record, providing complete traceability throughout the product life cycle.

Product Configuration Code

• D = Double Leg

• O = Oblong Master Link

• S = Sling Hook with Latch

DOS therefore refers to a Double Leg Chain Sling fitted with an Oblong Master Link on the top and Sling Hooks with Latch on the bottom.

Custom Manufacturing

TOPONE CHAIN can manufacture DOS chain slings according to customer requirements, including:

• Custom sling lengths

• Special hook configurations

• Master link options

• Identification marking

• Working load requirements

• Special lifting assemblies

All chain slings are supplied with written certification and are manufactured using matching Grade 80 components to ensure compatibility throughout the lifting system.

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 DOS Chain Sling – Double Leg w/ Oblong Master Link on Top and Sling Hooks w/ Latch 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, two-point lifting, machinery handling, structural steel erection, equipment installation, precast concrete handling, mining maintenance, and industrial material handling operations.

Maintenance Standards: Inspect before each use for chain elongation, wear, cracks, corrosion, hook deformation, latch operation, damaged master links, connecting links, and identification tags. Remove the sling from service immediately if defects exceed the applicable inspection criteria.