Dry Dock - Anchor Chain Cable Inspection

During an anchor chain inspection, the chain cables should be ranged out on the dock floor and visually inspected for wear and the link diameter is measured .Generally the overhauling of each shackle has been omitted .All anchor chains are stud chains .

Chin rinks are made of steel bar or cast steel. In case of ULCC and VLCC almost all are of cast steel.
Anchor Cable Accessories
1) Anchor shackle
Large shackle used for connecting the chain cable and the anchor
(2) Joining shackle
AS above mentioned, shackles used for connecting two chain cables; if studless end links are not provided at both ends , this shackle cannot be used.
(3) Kenter shackle
Shackles used for connecting a chain consisting　of common links only
and no end links.
This shackle has a split construction, therefore, it can be used to connect a broken chain, irrespective of where the break has occurred. It is more expensive than the joining shackle; dismantling this shackle is a little difficult.
(4) Swivel
Swivel is ijoined close to the anchor, it has the role of preventing twists in the chain cable due to its rotation. If a swivel is not provided in the chain, the links in the chain may be twisted

Length and Joining
The length of chain is defined as the distance between the inside edge of the link at one end and also the inside edge of the link at another end is  27.5 m. These chains are joined with shackles to form a length that complies with the requirements of the Equipment Number. The number of links in a chain is an odd number so the shackle always comes at the same position on the gypsy wheel of the windlass. To remove the twists of chain cable, a swivel piece is sometimes connected between anchor and the chain cable. The number of links in the swivel piece is even number



Matufacturing process
  Welding : The almost all chains are made by electrically welding.
  Casting  steel :The big chain for ULCC and VLCC is manufactured by casting. 
  By casting different strength steel chain can be made.
Strength
There are three kinds of chain cables depends on the maerial as follows:
1) Normal strength
2) High strength
3) Extra high. strength



Kind of chain cable
There are two kinds of chain cable depends on the joining means.
(1）With end and enlarged link at both ends
When connect using a ordinary joining shackle, both end links do not have studs for inserting the head of shackle. Then the diameter is bigger than the common link.The links of both ends are called end link and the next one to the end link is called second link. Both links have a bigger diameter .Without the two links at the ends, all other links are called common links.
(2) Common links only
When connection using a kenter shakles, there are neither end link nor second link. All are common links.

Connection of Chain Cable
The length of anchor chain cable is  27.5m. So it is necessary to jion each other using shackles. There are two type of shackles.
One is a joining shackle and the others is a kenter shackle