Russian Maritime Register of Shipping (RS) introduces new class notation distinguishing mark POSIMOOR-FIX and specifies the existing requirements to position-keeping / position mooring systems of ships and offshore facilities.
The relevant Circular letters (No. 312-11-1523c amending the Rules for the Classification and Construction of Sea-Going Ships and No. 314-51-1510c amending the Rules for the Classification, Construction and Equipment of MODU and FOP) are accessible at rs-class.org in the Online Information – RS Circulars section and enter into force on April 15, 2021.
The distinguishing mark POSIMOOR-FIX may be assigned to non self-propelled ships and offshore installations equipped with position mooring systems.
It is utterly important to consider operational and extreme environmental conditions during design of position-keeping systems and their elements. The new additional requirements to position-keeping systems specify the relevant calculation procedure depending on the time spent in the area of operation and direction of external loads.
For instance, recommendations are given for design load combinations based on their return periods.
A range of international requirements as well as operational experience regarding units equipped with position-keeping systems have been analyzed while elaborating RS requirements which will be applied during plan approval of ships and offshore facilities, contracted for construction or conversion on or after April 15, 2021. Starting from this date, the new requirements may also be applied to existing units in operation that are equipped with position-keeping / position mooring systems.