中文
A single point mooring (SPM) is a buoy/pier fixed at sea to handle liquid cargo such as petroleum products for tankers. Single point mooring moors the tanker to a mooring point through the bow, allowing it to swing freely around that point, minimizing the forces generated by wind, waves and currents. SPM is mainly used in areas without dedicated liquid cargo handling facilities. These single point mooring (SPM) facilities are located miles away from onshore facilities, connecting subsea oil pipelines, and can berth large-capacity vessels such as VLCC.
CDSR oil hoses are widely used in SPM system. The SPM system includes catenary anchor leg mooring system (CALM), single anchor leg mooring system (SALM) and turret mooring system.
Catenary Anchor Leg Mooring System (CALM)
Catenary Anchor Leg Mooring (CALM), also known as Single Buoy Mooring (SBM), is a dynamic loading and unloading buoy used as a mooring point for oil tankers and as a connection between the pipeline end (PLEM) and shuttle tanker. They are commonly used in shallow and deep water to transport crude oil and petroleum by-products from oil fields or refineries.
CALM is the earliest form of single point mooring system, which greatly reduces the mooring load, and it buffers the impact of wind and waves on the system, which is also one of the main characteristics of single point mooring system. The main advantage of CALM is that it is simple in structure, easy to manufacture and install.
Single anchor leg mooring system (SALM)
SALM is very different from traditional single point mooring. The mooring buoy is fixed to the seabed by an anchor leg and connected to the base by a single chain or pipe string, and the fluid is transported from the base on the seabed directly to the ship through hoses, or transported to the ship by a swivel joint through the base. This mooring device is suitable for both shallow water areas and deep water areas. If it is used in deep water, the lower end of the anchor chain needs to be connected to a section of riser with oil pipeline inside, the top of the riser is hinged with the anchor chain, the bottom of the riser is hinged on the seabed base, and the riser can move 360°.
Turret mooring system
The turret mooring system comprises a fixed turret column held by an internal or external vessel structure via a bearing arrangement. The turret column is secured to the seabed by (catenary) anchor legs that help maintain the vessel within a design excursion limit. This ensures the safe operation of the subsea fluid transfer or riser system from the seabed to the turret. Compared with many other mooring methods, the turret mooring system offer the following advantages: (1) simple structure; (2) Less affected by wind and waves, suitable for harsh sea conditions; (3) suitable for sea areas with various water depths; (4) It come with the fast disengagement and re-connection function, which is convenient for maintenance.
Date: 03 Apr 2023