Dibblee
ZMP Zinc Mooring Chain Anode
ZMP Zinc Mooring Chain Anode
Quoted on request. Price depends on the steel market and freight to your port. Tell us your port and specification and we will quote it delivered.
Contact Us For A QuoteZMP Zinc Mooring Chain Anode
The mooring chain anode: zinc cast on a pipe core to clamp onto stud link chain, for grade FM3 chain from 1-1/4 in to 4 in nominal.
Zinc sacrificial anode to MIL-DTL-18001L, type ZMP — mooring chain anode, pipe core. Quoted on request.
Sizes
| Type | Size | Spec figure |
|---|---|---|
| ZMP | Sized to chain — 1-1/4 in to 4 in nominal stud link | Fig 28 |
Full dimensions, in inches and millimetres together, are on the specification drawing in the images above — that drawing is the only place those dimensions exist in both units.
ZMP: 0.13 to 2.00 kg (0.28 to 4.41 lb) across the range
For the whole mooring
The ZMP clamps onto stud link chain, so it belongs with the rest of the mooring. We supply the chain and the Kenter joining shackles as well — ask and we will quote the lot together.
Alloy and water
MIL-DTL-18001L is a zinc specification, supplied to ASTM B418 Type I — the alloyed seawater grade whose composition is written to meet MIL-A-18001K. That is why every supplier's datasheet claims to "meet or exceed military specification".
For fresh water zinc is the wrong alloy: use magnesium to ASTM B843, or zinc to ASTM B418 Type II, the high-purity grade for fresh and buried service. We cast to either — say which water it is going into and we will quote the right one.
What to put on your purchase order
Zinc anodes fail by passivating: they skin over and stop producing current while still looking perfectly serviceable. Iron contamination is the usual cause, which is exactly what ASTM B418 caps at 0.005%. Specify "to ASTM B418 Type I, mill certificate with each lot" and you have something to test against.
Sizing
The specification sets what the anode is, not how much of it you need. That comes from DNV-RP-B401 for ships and offshore structures and ABYC E-2 for boats. Whatever the calculation says, replace at about 50% wasted — output falls away as surface area is lost, so the last half protects far less than the first.
Reading the type code
These designations come from the military specification, not from any manufacturer, which is why the same letters appear across every brand and why an old anode can nearly always be identified. Three letters: metal, then shape, then core. Z is zinc; H hull slab, S submarine slab, T teardrop, E fairwater slab, R rod, B bar, D disc, M mooring chain; then S steel strap, B brass straps, C core strap, P pipe core, M interlocking core, N no core.
