OCIMF: Proper handling and storage of STS Hoses

June 23, 2021 Maritime Safety News

OCIMF released a new information paper to provide guidance on the Handling, Storage, Use, Maintenance and Testing of STS Hoses.

Namely, OCIMF offers guidance to STS Service Providers, Masters, and operators of ships that use hose assemblies to transfer liquid-bulk cargoes via STS and to minimise hose damage from improper handling and storing.

To remind, hose strings used during Ship-to-Ship (STS) transfers in a side-by-side configuration are a critical link between the two ships. They are subjected to repeated lifting, bending and folding and to the dynamic forces of ship movements at sea. All of these can result in loads and stresses within the hose.

To provide greater reliability and longer life, hoses should be handled, stored, maintained, inspected and tested correctly at appropriate intervals.

Information about the size, length, type and quantity of the hose strings being delivered should be provided to the ships involved in the transfer so they can prepare their manifolds in advance. Any hoses supplied for the transfer should be provided with the most recent test certificate for tests undertaken at intervals not exceeding one year. More stringent testing frequency may apply based on local regulations.

When employed, the STS Provider’s representative should be on deck in the manifold region of one of the vessels and visible to both ship’s crew in order to ensure safe hose-handling practices are observed during hose connection and disconnection.

A competent ship’s officer should be on deck during the handling and assembly of the STS transfer hoses and take a lead role in the management of STS hose operations aboard their ship, including:

  • Lifting hoses from the Lightering Support Vessel (LSV) onto the ship
  • Hose deployment to other ship including verification of hose securing/supporting arrangement
  • Hose string assembly
  • Hose connection
  • Hose deployment to the other ship
  • Hose disconnection and draining
  • Hose recovery
  • Disassembly
  • Lowering hoses down from the ship deck into the LSV

In 1990, a new type of rubber cargo hose was developed to meet the unique requirements of offshore STS transfers. It is important to note that rubber STS hoses do not conform to any internationally recognised standard such as the International Standards Organization (ISO), British Standards (BS) or European Standards (EN). Manufacturers generally align with BS EN 1765 Rubber Hose Assemblies for Oil Suction and Discharge Services for the assemblies.

Rubber STS hose assemblies closely align with the specifics of EN 1765 Type L (Light Weight) Hoses. Type L hoses are helix-free, do not suffer permanent deformation and are designed to be used where light weight, ease of handling and increased flexibility is required. They differ from the standard in that:

  • They feature a heavy-duty design with a high burst safety factor.
  • The cover may be designed to be more durable but with reduced oil-resistant properties.
  • STS hoses are commonly rated for 15 bar Maximum Working Pressure (MWP).

Other hose types may be used in STS operations depending on geographical location, local requirements and other specific operational needs. Further guidance on specific hose types should be sought from the hose manufacturer.