SMIT brackets

SMIT bracket towing and mooring

SMIT brackets enable quick connection of a chafing chain link.

SMIT bracket arrangements are fitted to FPSO, rigs and other vessels.

SMIT brackets are useful points for rigging to connect mooring lines/towing chains for offshore commissioning, heading control and towage operations.

In certain FPSO operations, SMIT brackets can be used for station keeping and heading control operations.

The SMIT bracket is welded to vessel deck or at pontoon levels for rigs.

SMIT bracket OCIMF definition

The SMIT bracket is designed and specified to withstand the expected breaking load of the chain being used.

OCIMF defines the SMIT bracket as a “fitting for securing the end link of a chafe chain consisting of two parallel vertical plates mounted on a base with a sliding bolt passing through the plates” (OCIMF Mooring Equipment Guidelines MEG4, Fourth Edition 2018).

Typical SMIT manual operated towing bracket design as defined by OCIMF

SMIT brackets are usually made of high-quality grade steel.

SMIT bracket perceived as a method for emergency quick release

Due to its simple design, the SMIT bracket enables quick chain connection and disconnection and has been used for emergency towing.

Due to the convenience of being in the location where mooring activity is concentrated, the SMIT bracket has been wrongly associated with emergency chain disconnection.

Risk associated with using SMIT brackets in emergency situations

To release the chafing chain from the SMIT bracket, an operative has to manually drive the securing pin out of the SMIT bracket with a sledgehammer.

When the chafing chain is slack, this may be achieved with a relative degree of safety. However, if the chain is under tension with both vessels pulling from each other then releasing a chain under a 200T tension can pose a serious risk to both personnel and deck infrastructures.

In this circumstance, the amount of energy stored in a chain is enormous and on disconnection, the release of this uncontrolled energy from the chain can result in unpredictable consequences.

In certain offshore operations the SMIT bracket is therefore still considered as a method to quickly disconnect a chain. However, there are risks associated with the use of SMIT brackets in emergency disconnect situations.

Device used to mitigate risk when releasing a chain under tension

The OCIMF has in its 2020 FPSO Heading Control Guidelines, recognized that the safer alternative to using a hammer to disconnect a chain from the SMIT bracket is an emergency release device such as the Gall Thomson Powered Offshore Disconnect (PODx).

The use of PODx does not require crew to stand next to the SMIT bracket during an emergency disconnection process.

PODx is a simple, offshore proven system that allows chain release under tension. The PODx is made of two simple blocks and a release and reset bolt activated via a compact HPU.

The HPU enables manual and remote activation of the PODx so that the chain is released in a safe and controlled manner.

PODx provides a range of safe working load specifications from 2.5 Tons to 600Tons.

More on PODx Quick Mooring Release click
PODx FPSO Case Study click