Refractory Anchors

For lower temperature applications where budget is the main priority, 304 Stainless Steel is the entry-level option. It is effective up to approximately 1400°F (760°C) and is commonly used for backup linings or standard boilers. However, it is not designed for high heat; pushing it beyond this limit will cause rapid oxidation and scaling, acting much like mild steel would under stress.

For most industrial applications, 310 Stainless Steel is the standard "workhorse" choice. It contains higher levels of Chromium and Nickel, allowing it to withstand temperatures up to 2100°F (1150°C) while forming a protective skin against oxidation. It is generally the best option for furnaces burning coal or oil because it resists sulfur attack better than higher grade alloys. The main downside is that 310 SS can become brittle over time if held at intermediate temperatures, meaning it might snap if hit with a hammer during maintenance.

If your project requires extreme performance, Inconel 601 is the premium solution. It can survive temperatures exceeding 2200°F (1200°C) and offers exceptional resistance to thermal shock, meaning it won't crack during rapid heating and cooling cycles like stainless steel might. While it is significantly more expensive, it remains ductile and strong throughout its lifespan. However, you must avoid Inconel if your fuel source contains high sulfur, as the sulfur will attack the high nickel content and destroy the anchor.

V-Anchors are the industry standard for almost all general repairs. They are perfect for single-layer concrete linings that are roughly 3 to 10 inches thick. Because the "V" shape spreads out into the material, it holds the lining securely to the wall while still allowing the metal to expand slightly as the furnace heats up. If you are doing a standard job on a boiler or kiln, this is usually the safest and most cost-effective choice.

Y-Anchors are the heavy-duty alternative designed for much thicker or multi-layer walls. Unlike the V-anchor, these have a straight "stem" at the bottom before splitting. This stem allows you to anchor the concrete further away from the steel shell, which is critical if you have a soft insulation layer behind the hard concrete face. You should generally choose a Y-Anchor if your lining is thicker than 10 inches or if you need extra strength to support a heavy load.

Crook Anchors (often called J-Hooks) are specialized tools for tight spaces or very thin linings. A standard V-anchor is often too wide or tall for a lining that is less than 2 inches thick, so the Crook anchor is used instead because of its compact, low-profile shape. Unless you are working with a very thin patch or specific brickwork, you will likely not need this type.