Your Marine Sanitation Device Analysts Say That Quality Is Worth the Money
Raritan Engineering would love to share with you this week amazing information on how you can gain the needed knowledge in choosing the best anchor for your needs.
Each time Practical Sailor conducts an anchor test, we get questions about the materials used in anchors, particularly stainless steel. Stainless steel is much less prone to unsightly and destructive oxidation than mild steel, even when it has been hot-dipped galvanized and protected by a heat-bonded zinc coating.
Unfortunately, zinc is a relatively soft metal. As an anchor rubs and scrapes the bottom in its normal operation,the galvanized coating is damaged, mild steel uncovered, and oxidation begins. In many cases, however, rust can be a good friend, announcing to the skipper, with an undeniable bold red stain and flaking metal, that corrosion is taking place.
Even when shackle or swivel approaches failure, its surface patina may hardly change at all. The metal also tends to work-harden, and when submerged for long periods, suffers from oxygen starvation. Thus, its shiny appearance may have made it the diamond earring of anchor alternatives, but the same looks and assumed good quality, throughout the fatigue cycle, can present problems.
Design plays an important role in how well an anchor holds a vessel in place, and how well the anchor itself holds together. In essence, it’s a fairly simple structure, and it provides a good lesson in how loads migrate through a material and where stress accumulates. The shank, like the handle of a frying pan, transmits the energy into the main structure, and the junction between the handle and pan or shank and fluke is where a significant stress riser develops. Engineers know that stress escalates at the point where a flexing arm attaches to an immovable body.
When a vessel is dancing to the thrum of a building gale, the surging loads imposed on the anchor shank vary in both intensity and angle, and when the fluke(s) of the anchor ends up wedged in a rocky outcrop or pinned in a coral pothole, the anchor’s shank and the fluke(s) themselves need to be rugged enough to handle loads imposed.
Your Marine Sanitation Device Experts Help You Gain the Confidence to Make the Right Choice
Your marine sanitation device specialists know that many bluewater veterans swear by U.S.-made galvanized mild steel shackles and chain, and agree that swivels, although a necessity for mooring pendants, should be omitted from anchor rodes.
How to choose the right anchor
Until the 1930s, there was little choice when it came to purchasing an anchor, the Fisherman being just about the only type available.
The Main Key attributes of a good anchor
Most anchors are steel, galvanized for corrosion resistance. The carbon content should be below 0.21% to ensure ductility at all likely temperatures.
Aluminum and stainless steel anchors require either sophisticated alloying or clever design features, such as hollow shanks, to obtain sufficient strength. This makes them expensive.
However, the excellent performance of various types of aluminum anchor, both in tests and in the real world, shows quite clearly that weight is not necessarily a prerequisite for good holding power. It is a truism that anchors are marketed by weight but they hold by their area. Most modern anchors have a lot more surface area than older types of the same weight.
Learn more from Raritan Engineering about the importance of choosing the right marine sanitation devices for your needs.