Ship Anchor Chain

-
Image result for Ship Anchor Chain
A heavy chain used for holding a vessel at anchor. The total length of chain is to be divided in approximately equal parts between the two bower anchors. The inboard ends of the chain cables are to be secured to the ship’s structure by means which enable, in case of emergency, an easy slipping of the chain cables to sea. Ship Anchor chain and chain accessories are to be produced by manufacturers approved by classification society. All chain is to have a workmanlike finish and be free from injurious defects. There is to be an odd number of links in each shot of anchor chain cable to insure shackles leading over the windlass are in the same position.
The steel used for the manufacture of chain is to be made by the open-hearth, basic-oxygen, electric-furnace or such other process as may be specially approved.
Rimmed steel is not acceptable for any grade of chain.
For approval purposes, the manufacturer is to submit a manufacturing procedure specification, applicable material grades, and dimensional details of chain/accessories along with a test plan for classification society review. The approval tests, as a minimum, are to include: chemical analyses, proof and break load tests, tensile/impact tests, metallographic examinations, dimensional measurements, visual and non-destructive examinations. The approval tests are to be witnessed by an attending Surveyor and the test-data are to be submitted to classification society for review and acceptance. The approval is valid for a maximum of 5 years and the renewal process is to be on similar lines.
Locking pins in detachable connecting links are to have taper contact at both top and bottom in the link halves. Lead or other acceptable material is to be used for plugging the locking pin hole which is to contain an appropriate undercut recess or equivalent arrangement to secure the plug.
Image result for Ship Anchor Chain

Comments

Post a Comment

Popular posts from this blog

Introduction to Mooring Line

-
Image
The mooring refers to any permanent structure to which a vessel/ship may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore. As a verb, mooring refers to the act of attaching a vessel to a mooring. Mooring is often accomplished using thick ropes called mooring lines or hawsers. The lines are fixed to deck fittings on the vessel at one end and to fittings such as bollards, rings, and cleats on the other end. Mooring requires cooperation between people on a pier and on a vessel. Heavy mooring lines are often passed from larger vessels to people on a mooring by smaller, weighted heaving lines. Once a mooring line is attached to a bollard, it is pulled tight. Large ships generally tighten their mooring lines using heavy machin
Read more

Anchor Size- rigging table

-
Image
After having found the equipment numeral from previous blog , the details regarding sizes and quality  may be obtained from the rigging tables provided in these regulations. From these table , we can find the following information The Equipment Letter Stockless bower anchors number of anchor Mass per anchor (kg) Stud-link chain cables for bower anchors Total length (m) Grade and Diameter (mm) of chain CC1———— low  strength. CC2———–medium strength. CC3———–high strength Towline Minimum length (m) Minimum breaking strength (KN) Mooring Lines Number Length of each mooring ropes (m) Minimum breaking strength (KN)
Read more

Introduction to Towline

-
Image
A tow line is used with a tug (tugboat or towboat) which is a type of vessel that maneuvers other vessels by pushing or pulling them either by direct contact or by means of a tow line. Tugs typically move vessels that either are restricted in their ability to maneuver on their own, such as ships in a crowded harbor or a narrow canal, or those that cannot move by themselves, such as barges, disabled ships, log rafts, or oil platforms. A tow line is the essential link between tug and ship. This applies to tugs operating alongside a vessel in the push-pull mode as well as to towing tugs fastened with a tow line to the bow or stern of a ship, also called `tugs towing on a line‟. Basic towline requirements A towline must fulfil two basic functions, firstly to function as the load-carrying link between tug and ship and secondly to cope with the dynamic loads resulting from the relative motion between tug and ship. This leads to the following basic requirements for towlines for harbo
Read more