Do you already have the right anchor chain for your ship?

The right choice, corresponding to the intended use, will determine the life cycle of the chain and ensure anchoring safety, even in adverse conditions.

April 27, 2023
Nautic

The right choice, corresponding to the intended use, will determine the life cycle of the chain and ensure anchoring safety, even in adverse conditions.

WHAT MATERIAL SHOULD AN ANCHOR CHAIN BE MADE OF?

The high-quality stainless steel chains of cromox® provide twice the breaking strength of conventional galvanized steel chains. As an additional benefit, their smooth surface prevents piling up in the chain locker. In general, non-corrosive steels with a PREN value of at least 33 are regarded as seawater-resistant. The cromox® Duplex material 1.4462 (AISI 318LN) has a PREN value of 35, and is thus seawater-resistant up to 94 °F (34 °C).

QUALITY FEATURES OF A PREMIUM-QUALITY ANCHOR CHAIN "MADE IN GERMANY"

The stainless steel anchor chains of Ketten Wälder GmbH are solely manufactured at their production site in Germany, in compliance with standardized machine welding procedures and in a consistently reproducible quality.

Unlike manual welding, machine welding processes assure constant precision and tensile strength of the manufactured chain links, thereby vouching for the safety of the entire anchor chain. They are subject to DIN 766 standard in terms of production, and to DIN 685 standard in terms of test procedures.

One of the decisive factors for the corrosion resistance of cromox® stainless steel anchor chains is the surface quality or surface treatment. With the option of electropolishing, the micro-roughness of the material may be reduced. This in turn reduces the adhesion/build-up of residues (dirt, algae etc.), and consequently improves the overall cleanability.

By the way, we can customize your cromox® chain by personalizing the individual chain links with any name of your choice, thus creating a coherent image in terms of superior quality and a striking appearance: your ship and its high-gloss polished, customized stainless steel anchor chain.

ENVIRONMENTAL FACTOR: GALVANIZED ANCHOR CHAINS VS. STAINLESS STEEL ANCHOR CHAINS

Furthermore, it is important to note that zinc concentrations in seawater have by now reached an alarmingly high level, which again poses a serious threat to aquatic life as zinc produces acute toxicity. Given the fact that in the course of corrosion processes, which are prevalent in and typical for galvanized anchor chains, substantial amounts of zinc are released into seawater at times, this destructive development is even further supported.

The cromox® stainless steel anchor chains, however, make an active contribution to the protection of marine life by uniting the aspects of exceptional durability with the philosophy of consistent environment-friendliness and sustainability.

TEMPERATURE FACTOR

Stainless steel anchor chains may also be used at higher temperatures. Here, the specific material as well as the duration and location of use are decisive – please refer to the following table:

Material	Quality grade	Breaking force at 8 mm Chain Thickness (Optimum Value) (kN)	PREN	CPT (°C)
AISI 316L	60	63	23,10 – 28,50	24 – 27,5
AISI 318LN Duplex	60+	66	30,85 – 38,07	27,5 – 34,5
AISI F255 Superduplex	70+	80	37,00 – 44,00	> 70

WHICH CHAIN SIZE FOR WHICH SHIP?

The various chain sizes feature different tensile and breaking forces. For this reason, the chain diameter depends both on the size and the weight of the ship – please refer to the following overview:

Anchor weight (kg)	Sailing boat		Motor boat		Catamaran		Chain (d/mm)
Anchor weight (kg)	Weight (t)	Length (feet)	Weight (t)	Length (feet)	Weight (t)	Length (feet)	Chain (d/mm)
5	1	17	1.1	17	0.7	14	5
8	2	23	2.2	24	1.4	20	6
12	3.8	30	4.2	31	2.7	26	6
16	6.3	35	6.9	36	4.5	31	6 – 8
21	10.2	41	11.2	43	7.3	36	8
27	14.6	47	16	48	10.5	41	8 – 10
35	21.5	52	23.5	54	15.6	45	10
45	30	58	32.9	60	21.6	51	10 – 12
60	43	66	47.1	68	31	58	12 – 13
80	63	73	69	75	45.4	63	13
100	85	80	93	83	61	70	14
130	123	90	135	93	89	78	14 – 16
160	174	100	191	103	125	86	16
200	262	113	287	116	190	98	18
250	400	129	438	133	290	111	18 – 20
300	550	144	600	149	400	125	20
360	760	164	830	169	550	142	22

WHAT CHAIN LENGTH IS REQUIRED?

Depending on the highest wind force values at your particular sailing locations, the required anchor chain length varies as follows:

COMPARISON: WIND FORCE – WATER DEPTH – ANCHORAGE LENGTH

Wind force	Anchorage length
up to 10 knots	5-fold anchor depth
up to 35 knots	7-fold anchor depth
over 35 knots	10-fold anchor depth

WHAT'S THE NEXT STEP?

In order to find the ideal anchor chain for your ship, you have now already received a useful and basic first overview, allowing you to match and identify the criteria relevant to you.

As a next step, in-depth consultation will be essential, since there are numerous different influences and factors determining the choice of material, so only professional expertise and advice are going to ensure you are provided an anchor chain that precisely meets your individual requirements.

We will be pleased to explain all the details to you. Feel free to contact us.

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