Tugboat hook GS

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Overview
The Straatman quick-release towing hook (disc type) is a deck-mounted device engineered for safe towing on workboats, supply vessels, harbour vessels and tugs. It secures a towing line and enables a controlled, immediate release while the line remains under tension, reducing manual handling risks and improving emergency response times.

What is a quick-release towing hook?
A quick-release towing hook secures a towing line on deck and permits fast, controlled release under full tension up to the hook's rated capacity. The function enhances crew safety and operational control during towing and emergency situations.

Release-under-load capability
Straatman quick-release hooks are designed to release the towing line under full tension up to the certified Safe Working Load (SWL), delivering predictable operation and controlled energy dissipation at release.

Quick-release towing hooks type GSH
The Straatman GSH series is a manual disc-type towing hook operated by lever or rope. Operating effort remains below 33 lb (approx. 15 kgf) even at full SWL. An integrated two-step release reduces accidental opening. The counterbalanced disc limits impact energy and allows rapid controlled manual resetting after release.

Quick-release towing hook type GMH
The Straatman GMH series combines mooring and towing functions. Standard equipment includes a rope keeper to secure towing operations and to facilitate switching between mooring and towing while maintaining safe control.

Configuration and options

• Spring-loaded shock absorber
• Customised hook geometries
• Local hydraulic or pneumatic release
• Remote-controlled release
• Load monitoring and alarm systems
• Foundations, brackets or towing posts for deck integration

Testing and verification
Each Straatman hook is tested on a calibrated hydraulic test rig with capacity up to 3,500 kN. Disc-type hooks undergo proof load testing up to 200% of SWL; the GSH-100 is tested to 150% SWL per design criteria. Release function is verified at SWL and classification authority witnessing can be arranged on request.

Special designs and project-specific solutions
Straatman offers project-adapted solutions including integrated foundations for direct welding to the vessel deck and hydraulic shock absorbers developed with partners to improve load control and simplify installation in demanding applications.

What to expect from Straatman

• Over 50 years of specialised experience
• Dutch engineered products
• Proven release-under-load concepts
• Long-term service and spare parts support

Technical specifications

• Safe Working Load (SWL) range (GSH): 15 to 100 tonnes
• Operating force to release: below 33 lb (≈15 kgf) at full SWL
• Release capability: controlled release under full tension up to rated capacity
• Proof load testing: disc-type hooks tested up to 200% SWL (GSH-100 tested to 150% SWL per design)
• Test equipment capacity: calibrated hydraulic rig up to 3,500 kN
• Release mechanism: integrated two-step release to reduce accidental opening
• Design features: counterbalanced disc for limited energy impact and rapid manual resetting
• GMH specific: standard rope keeper for combined mooring and towing operations
• Operation: manual lever or rope; optional hydraulic, pneumatic or remote-controlled release