Anchor equipment is an important piece of deck equipment on board ships. It slows down the ship when it docks at the dock or navigates in narrow waterways, assists the ship in getting out of shallow water when it is grounded, and controls the ship’s speed in an emergency before there is a risk of collision,etc.Anchor equipment mainly consists of anchors, anchor chains, anchor windlass, anchor chain barrel, chain stopper, anchor chain tube, anchor chain cabin, and chain abandonment device.

ANCHOR

There are many types of anchors. According to their structure and purpose, they can be divided into anchors without poles, anchors with poles, anchors with high holding power, special anchors, etc.

A pole anchor is also called a naval anchor. The anchor stem and the anchor claw are cast as a whole, and the anchor claw will not rotate. It is characterized by simple structure and large grip-to-weight ratio.

MAIN TECHNICAL REQUIREMENTS FOR ANCHOR MACHINES

1.Driven by an independent prime mover or electric motor and capable of reversing;

2.Should be able to pull an anchor from a depth of 82.5 meters underwater to 27.5 meters at an average speed of no less than 9m/min;

3.The ability to work continuously for 30 minutes;

4.Work for 2 minutes under an overload pressure of no less than 1.5 times the working load;

5.Equipped with clutch and locking device;

6.The sprocket is equipped with a reliable brake;

7.The installation of the anchor machine should generally ensure that the anchor chain cylinder, chain stopper, and sprocket are aligned;

8.The remote-controlled anchor should have a fast acting emergency stop mechanism, and the sprocket should be equipped with a reliable brake.

After the brake is tightened, there should be no permanent deformation of the load-bearing parts and no slipping of the braking device under the following loads: 1. For anchor machines equipped with chain stoppers, they should be able to withstand 45% of the static tension of the broken anchor chain load or the maximum static load on the anchor chain; 2. For anchor machines without chain stoppers, they should be able to withstand 80% of the static tension of the broken anchor chain or steel cable.

The prime mover and transmission device should be equipped with overload protection to prevent excessive torque and impact.

CORROSION LIMIT OF ANCHOR EQUIPMENT

The average diameter of any worn chain link in an anchor chain shall not be less than 88% or 85% of the original standard diameter. The wear limit of the connecting links, anchor shackles, swivel rings, and their bolts is the same as above.

The weight loss of the anchor should not exceed 20% of the original anchor weight. If the base of the anchor machine is corroded to 25% of the original thickness, it should be replaced or strengthened. If the base bolts and nuts are severely corroded, they should be replaced.

THE MAIN DEFECTS OF ANCHOR EQUIPMENT

Defect 1: The orientation of the left anchor claw is incorrect

Defect 2: Wear and tear on the brake band of the anchor machine

Defect 3: Corrosion and damage to anchor chain pipes

Defect 4: The ends of the left and right anchor chains are not connected to the ship’s hull through the chain abandonment device as required by the specifications.