Home > news > Content
Andun Rubber Company tells you about the characteristics of the bollard
- 2019-04-23-

The bollard pull is a mooring device that uses a cable or chain to tie the ship to a designated location. Ships entering and leaving the port and relying on the dock are inseparable from the boat equipment. Mooring equipment includes various cables, bollards, mooring buoys, and the like. Usually ship mooring equipment is installed at the bow and stern.

Function characteristics

The bollard is a small and conspicuous small accessory member on the surface of the wharf (the high-pile wharf is above each platform), which is used to transmit the mooring force when the ship is docked to the wharf structure. The cost of the bollard is small in the whole dock project and it is difficult to design. However, it is an indispensable accessory component on the dock. Its function and sensory effect play a key role in the whole dock.

material selection

The current bollard cylindrical shell material of the current bollard universal diagram design is gray cast iron or cast steel. Gray cast iron has a low unit price, good casting performance, good wear resistance and superior anti-corrosion performance, but low strength and poor ductility. Cast steel has high strength and good ductility, but its casting performance and wear resistance are not as good as cast iron, and it needs to be regularly rust-proofed. Ductile iron combines the advantages of gray cast iron and cast steel, and at the same time discards the fatal defects of both: its strength is higher than that of cast steel, ductility is between gray cast iron and cast steel, good wear resistance and good corrosion resistance. There is no need for regular anti-corrosion maintenance.

Usually ship mooring equipment is installed at the bow and stern. The choice of the length and thickness of the mooring line should take into account the changes in the draught of the ship after unloading and the factors such as tides, winds and tides. Especially in harbors where waves or tides are easy to enter, in extremely severe weather such as typhoons or tidal orgasms, mooring lines are prone to breakage, causing collisions of ships with docks or stranding of ships. When the ship is to be moored near the dock, in order not to cause the ship to hit the dock, the crew and the land-based personnel need to work together.

At present, there are a variety of mooring systems for the positioning of floating structures. According to the method of mooring, they can be divided into catenary, catenary, anchored, single-anchor, single-anchor, and mooring. According to the number of mooring lines, it can be divided into single point mooring system and multi-point mooring system. Generally speaking, the way of mooring is determined according to the size of the mooring force, the depth of the water, the length of the lanyard, whether the floating body is configured, and the terrain. The current mooring system mainly adopts a multi-point mooring system. The steel cables used generally use catenary lines, and other composite materials such as nylon ropes generally use semi-tensioned moorings.