Why Anchor Chains Fail: The Most Common Failure Points and How to Spot Them Early
- Shake Sure
- Dec 28, 2025
- 4 min read
Anchor chain failure rarely happens without warning.Most of the time, the signs are there long before something goes wrong—but they’re easy to miss if you don’t know what to look for.
At ShakeSure, we see the same failure patterns over and over. The good news is that most of them are preventable with the right chain selection and early inspection.
Here are the most common reasons anchor chains fail and how you can catch issues early.
Reason 1: Zinc Coating Loss and Accelerated Corrosion
Most anchor chain failures start on the surface.
Hot-dip galvanized anchor chains rely on a zinc coating to protect the steel underneath. Over time, contact with sand, rocks, rollers, and chain lockers slowly wears that layer away.
Early warning signs include:
Dull grey areas turning dark or reddish
Uneven zinc thickness along the links
Rust forming first at contact points
Once the zinc layer is breached, corrosion accelerates rapidly—especially in saltwater. This is why zinc thickness and galvanizing quality matter far more than many buyers realize.
Reason 2: Weld Area Fatigue and Micro Cracks
Every anchor chain link has a weld, and that weld is always a critical point.
Failures often begin with:
Hairline cracks near the weld seam
Slight deformation on one side of a link
Links that appear stretched or elongated
These issues can be hard to see during casual checks. This is where proof testing plays a key role—weak welds are identified before the chain ever goes into service.
If one link looks different from the rest, it’s a red flag. One weak link compromises the entire chain.
Reason 3: Overloading Beyond the Working Load Limit
Anchor chains rarely fail under normal conditions. They fail when loads exceed what they’re designed to handle.
Common causes include:
Using an undersized chain for the boat
Sudden shock loads from wind or waves
Insufficient scope creating high tension
The Working Load Limit (WLL) exists for a reason. Repeated loading near or beyond that limit weakens the steel over time—even if the chain doesn’t break immediately.
Choosing the right grade, not just diameter, is critical for long-term safety.
Reason 4: Poor Calibration Causing Mechanical Damage
Some failures have nothing to do with corrosion.
Chains that are not properly calibrated for the windlass can:
Jam under load
Skip on the gypsy
Wear unevenly on specific links
This repeated mechanical stress leads to deformation, thinning, and early failure. The chain may still look strong, but internal damage is already happening.
Reason 5: Galvanic Corrosion at Connection Points
Mixing different metals creates another hidden risk.
When galvanized chains connect to stainless shackles or other dissimilar metals, galvanic corrosion can occur. The zinc sacrifices itself faster at those contact points, leading to localized corrosion that spreads inward.
Watch for:
Rapid zinc loss near connectors
Pitting around end links or shackles
Uneven corrosion patterns
Understanding how different metals interact helps avoid premature chain failure.
Spotting Problems Early Makes All the Difference
Most anchor chain failures don’t happen suddenly. They develop slowly—one worn link, one cracked weld, one corroded section at a time.
A Simple Anchor Chain Inspection Checklist
You don’t need special tools or technical training to spot early anchor chain problems. A few routine checks can tell you a lot about your chain’s condition and safety.
Here’s a basic checklist you can follow during regular use or seasonal maintenance:
Check the zinc coating first
Look closely at the chain links, especially the first several meters that see the most seabed contact. If you notice bare steel, deep discoloration, or rust forming through the zinc, the protective layer is reaching the end of its life.
Inspect the weld areas on each link
Focus on the welded seam of the links. Any visible cracks, sharp edges, or uneven shapes are warning signs. If one link looks different from the rest, it deserves attention.
Look for stretched or deformed links
Links should all have a consistent shape. Elongated, flattened, or twisted links indicate overloading or repeated shock loads, even if the chain hasn’t failed yet.
Watch for uneven wear patterns
If certain sections show heavier wear than others, it may point to windlass misalignment, poor calibration, or repeated jamming during retrieval.
Inspect connection points and end links
Areas where the chain meets shackles or connectors often corrode faster. Rapid zinc loss or pitting near these points can signal galvanic corrosion.
Listen and feel during retrieval
Grinding noises, skipping, or vibration when retrieving the chain through the windlass often indicate calibration issues or link deformation—even before visual damage appears.
Prevention Starts Before Failure
Regular inspection, choosing the correct chain grade, ensuring proper calibration, and using proof-tested chains all work together to reduce risk. Catching problems early doesn’t just extend chain life—it protects your boat, equipment, and safety.
That’s why ShakeSure focuses on more than selling anchor chains. We help buyers understand what to check, what matters, and when it’s time to act—so problems are solved before they turn into failures.
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