The Hammar H20 is the best-selling HRU in the world, and it has been saving lives on the oceans for more than 30 years. Its safe, reliable, and simple design has earned more worldwide approval than any other unit.

The H20 needs no annual service, maintenance, or spare parts. You simply install a new unit and dispose of the old once it has reached the end of service life.

What Does An Hru Do? 

If The Vessel Sinks, The Increasing Water Pressure Activates The Hammar H20. It Automatically Releases The Liferafts, Epirbs (emergency Position Indicating Radio Beacons), Or Other Life-saving Appliances It Is Connected To. 

The Hammar H20 Is Designed To Be Safe And Reliable In All Extreme Conditions That You And Your Ship Might Meet On The Oceans. The Manual Release Units (mru) And Electronic Release Units (eru) Allow For A Smooth, Controlled Release In An Early Stage Of Abandoning The Ship Without Compromising The Hydrostatic Function. 

The Hammar H20 - How It Works

Inside The Hammar H20, A Pin Under Tension Sits In A Notch Of A Spring-loaded Knife. The Pin Is Attached To The Center Of A Flexible Membrane. At The Intended Depth, Water Acts On The Membrane Pushing It Inwards And Out Of The Notch. When The Pin Is Fully Out Of The Notch, The Blade Can Instantly Spring Forward, Cutting Through The Strong Rope And Releasing The Lashing. 

The Weak Link™ Holds The Painter Line Assuring The Necessary Pull To Inflate The Raft As The Buoyancy Of The Liferaft Container Floats Towards The Surface. The Increased Buoyancy Of The Inflated Liferaft Will Cause The Weak Link™ To Break, And The Raft Can Surface. 

The Hammar H20 Is Designed To Cut Through The White Strong Rope But May, In Some Applications, Also Cut The Unshielded Electrical Cable. 

The H20 Dual Assembly allows for more than one release option and/or redundancy, or dual release points. This is achieved by connecting MRUs and ERUs to an HRU. This way, you can fulfill SOLAS requirements combined with RRS.

Dual Arrangement is supplied in various shapes and forms for installing. A few points are important for the correct function of the unit:

• In arrangements with two connections to a strong point (deck), these connection points need to be separated by 60 to 120 millimeters.
• The Weak Link™ may be either a red rope or a Weak Link™ system, depending on the arrangement. Confirm the Weak Link™ is the only thing holding the painter line after an automatic activation.
• Confirm the joint between the two rope slings is outside the stainless steel ring to avoid pinching upon release.