Ever wondered why do we sometimes have both the anchors of different lengths. It is not very uncommon to notice 10 shackles on one anchor while 11 shackles on other one. All the requirements concerning anchor onboard are formulated in the guidelines issued by International association of international classification (IACS). These requirements include requirements for anchor weight, diameter and steel grade for the stud link of the chain cable and the length of the anchor chain etc.
All these requirements are governed by something called “Equipment number”. If you would have seen the anchor certificate generally issued during yard delivery of the vessel, you would find the equipment number on that certificate.
Equipment number is calculated by formula
As per the equipment number, the total length of the anchor chain is given. So if say, for a particular equipment number, the minimum length of the cable required is 21 shackles, one side of the anchor is given 10 shackles and the other one 11 shackles. Below is the table that shows how equipment number corresponds to the particulars of the anchors onboard.
Did you find this information useful ? Let your views flow in the comments below. Meanwhile wishing you all fair winds and following seas.
About Capt Rajeev Jassal
Capt. Rajeev Jassal has sailed for over 19 years mainly on crude oil, product and chemical tankers. He holds MBA in shipping & Logistics degree from London. He has done extensive research on quantitatively measuring Safety culture onboard and safety climate ashore which he believes is the most important element for safer shipping.