SEA REFUELING

SHIP TO SHIP AT SEA

Replenishment at sea (NATO: Replenishment at Sea = RAS or Under-way replenishment = UNREP) refers to the supply of military ships at sea with fuel, spare parts, food, ammunition and other supplies and the transfer of personnel. Sea replenishment maneuvers can significantly extend the endurance of a warship at sea.

The ship requiring fuel approaches the supply ship from starboard aft and maintains a parallel course at the same speed at a distance of 30 to 60 meters.

The connection is first established by a line that is shot from one ship to the other with the bola.

A wire is passed over this line, which is stretched between the highest point of the refueling system and the RAS boom, along which the tank hose runs. This wire with tank hose, filler neck and funnel must be very well secured to the RAS boom by a holding and securing device, the so-called swivel arm. Considerable tensile forces are exerted during refueling.

After refueling, the safety hook (pelican hook) is released and the wire rope is returned with the tank hose and the filler neck. Sea conditions and continuous movement during refueling cause tension on the securing device, which can impair the release for the return and also lead to premature wear of these components.

NIOTEC has used the results of new calculations and extensive test trials together with the classification society DNV to develop a swivel arm design made of a special steel with a higher strength. The corresponding segments were modified and optimized for specific requirements with high loads. The new swivel arm, the NIOARM, has so far proven itself very well under all loads and requirements.

NIOARM

Swivel arm

Special safety devices are subject to high requirements and standards. Technical and professional requirements must be met for the design and manufacture in order to guarantee the implementation of such projects.

The safety hook (swivel arm) is an important and indispensable accessory for securing tank equipment during refueling at sea. Without this or a non-functional safety hook, refueling cannot be carried out.

NIOARM - Swivel arm reinforced and modified version

Material: High-strength chrome-nickel steel
Load requirement SWL (safe working load): 8 tons
Load requirement TL (tensile load): 16 tons
Acceptance classification: DNV