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- Offshore & Subsea HA Master Links OS+ Zinc Tough - WLL Range 7 tonnes to 75 tonnes

Offshore & Subsea HA Master Links OS+ Zinc Tough - WLL Range 7 tonnes to 75 tonnes
Certified to International Standards: DNV2.7-1, DNV2.7-3, BSEN ISO 10855-2, EN1677-4, ASME B30.26 and API-2CCU – Aug.2017. WLL Range 7,000kg to 75,000kg
OSHM-5142


The HA range of Grade 8 master links and quad assemblies are global industry leaders and are widely used for offshore rigging as well as container lifting sets.
- Certified to International Standards: DNV2.7-1, DNV2.7-3, BSEN ISO 10855-2, EN1677-4, ASME B30.26 and API-2CCU – Aug.2017.
- DNV GL Type Approval TAS00001BN Rev 2.
- Product available in diameters from 22mm up to 75mm and working load limits from 7 tonnes to 100 tonnes.
- The master link and quad assemblies are individually proof load tested to 2.5 times working load limit and 100% MPI.
- MPF (Manufacturing Proof Force): based on 2.5 x 9.81 x Working Load Limit (kN) (min.)
- BF (Break Force): WLL x Factor of Safety.
- WLL (Working Load Limit) @ 45° to vertical.
- Factor of Safety: 5:1.
- Embossing provides product identity plus individual manufacturing batch and date.
- Average impact energy (charpy) 42 Joules minimum impact resistance at -40°C up to 50mm diameter.
- Operational temperature range is -40°C to + 200°C.
- Incorporating Zinc ToughTM Technology.
Zinc ToughTM Technology
The Zinc-ToughTM Technology HA range of Grade 8 Master Links and Quad Assemblies provide superior protection from Hydrogen embrittlement and stress corrosion cracking - making them perfect for lifting operations in offshore environments.
Hydrogen embrittlement is the process by which metals such as steel become brittle and fracture under stress due to the introduction and subsequent diffusion of hydrogen into the metal - it can also be described as hydrogen assisted stress cracking and is particularly prevalent in the extreme conditions of the offshore environment where corrosion is a consistent threat. William Hackett and McKinnon Chain combined their technical knowledge and worked alongside a wide range of stakeholders, including several major oil and gas operators, to develop Zinc ToughTM Technology.
This unique manufacturing process delivers a master link with the tensile strength requirements to deliver a 5:1 safety factor with a hardness value as low as 34-36 HRC. The DNV charpy impact values are achieved at -40C, making the links ability to withstand a shock load at any operating temperature.
Dimensions & Specifications (DNV GL Type Approval TAS00001BN Rev. 2)
Description | A (mm) | B (mm) | C (mm) | WLL (t) | MPF (kN) | MBL (kN) | Weight (kg) |
HA22ML OS+ ZT | 22 | 270 | 140 | 7 | 172 | 343 | 2.28 |
HA25ML OS+ ZT | 25.5 | 270 | 140 | 9.3 | 229 | 456 | 3.11 |
HA28ML OS+ ZT | 28 | 270 | 140 | 14.5 | 356 | 711 | 3.78 |
HA32ML OS+ ZT | 32 | 270 | 140 | 19 | 466 | 932 | 5.02 |
HA36ML OS+ ZT | 36 | 270 | 140 | 26 | 638 | 1275 | 6.46 |
HA40ML OS+ ZT | 40 | 280 | 155 | 30.5 | 749 | 1496 | 8.46 |
HA45ML OS+ ZT | 45 | 320 | 175 | 40 | 981 | 1962 | 12.18 |
HA50ML OS+ ZT | 50 | 350 | 195 | 51 | 1251 | 2502 | 16.54 |
HA65ML OS+ ZT | 65 | 410 | 220 | 75 | 1840 | 3679 | 33.02 |
HA75ML OS+ ZT | 75 | 450 | 250 | 100 | 2453 | 4905 | 48.98 |

The HA range of Grade 8 master links and quad assemblies are global industry leaders and are widely used for offshore rigging as well as container lifting sets.
- Certified to International Standards: DNV2.7-1, DNV2.7-3, BSEN ISO 10855-2, EN1677-4, ASME B30.26 and API-2CCU – Aug.2017.
- DNV GL Type Approval TAS00001BN Rev 2.
- Product available in diameters from 22mm up to 75mm and working load limits from 7 tonnes to 100 tonnes.
- The master link and quad assemblies are individually proof load tested to 2.5 times working load limit and 100% MPI.
- MPF (Manufacturing Proof Force): based on 2.5 x 9.81 x Working Load Limit (kN) (min.)
- BF (Break Force): WLL x Factor of Safety.
- WLL (Working Load Limit) @ 45° to vertical.
- Factor of Safety: 5:1.
- Embossing provides product identity plus individual manufacturing batch and date.
- Average impact energy (charpy) 42 Joules minimum impact resistance at -40°C up to 50mm diameter.
- Operational temperature range is -40°C to + 200°C.
- Incorporating Zinc ToughTM Technology.
Zinc ToughTM Technology
The Zinc-ToughTM Technology HA range of Grade 8 Master Links and Quad Assemblies provide superior protection from Hydrogen embrittlement and stress corrosion cracking - making them perfect for lifting operations in offshore environments.
Hydrogen embrittlement is the process by which metals such as steel become brittle and fracture under stress due to the introduction and subsequent diffusion of hydrogen into the metal - it can also be described as hydrogen assisted stress cracking and is particularly prevalent in the extreme conditions of the offshore environment where corrosion is a consistent threat. William Hackett and McKinnon Chain combined their technical knowledge and worked alongside a wide range of stakeholders, including several major oil and gas operators, to develop Zinc ToughTM Technology.
This unique manufacturing process delivers a master link with the tensile strength requirements to deliver a 5:1 safety factor with a hardness value as low as 34-36 HRC. The DNV charpy impact values are achieved at -40C, making the links ability to withstand a shock load at any operating temperature.
Dimensions & Specifications (DNV GL Type Approval TAS00001BN Rev. 2)
Description | A (mm) | B (mm) | C (mm) | WLL (t) | MPF (kN) | MBL (kN) | Weight (kg) |
HA22ML OS+ ZT | 22 | 270 | 140 | 7 | 172 | 343 | 2.28 |
HA25ML OS+ ZT | 25.5 | 270 | 140 | 9.3 | 229 | 456 | 3.11 |
HA28ML OS+ ZT | 28 | 270 | 140 | 14.5 | 356 | 711 | 3.78 |
HA32ML OS+ ZT | 32 | 270 | 140 | 19 | 466 | 932 | 5.02 |
HA36ML OS+ ZT | 36 | 270 | 140 | 26 | 638 | 1275 | 6.46 |
HA40ML OS+ ZT | 40 | 280 | 155 | 30.5 | 749 | 1496 | 8.46 |
HA45ML OS+ ZT | 45 | 320 | 175 | 40 | 981 | 1962 | 12.18 |
HA50ML OS+ ZT | 50 | 350 | 195 | 51 | 1251 | 2502 | 16.54 |
HA65ML OS+ ZT | 65 | 410 | 220 | 75 | 1840 | 3679 | 33.02 |
HA75ML OS+ ZT | 75 | 450 | 250 | 100 | 2453 | 4905 | 48.98 |

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