Merkle Modu-Lok® System
An Interlocking Suspended Refractory System

Advantages of the Merkle Modu-Lok System

  • The Modu-Lok System utilizes pre-fired refractory which has a longer installed life and higher resistance to corrosion than plastic or castable systems.
  • Hanger and filler brick have structural, load-bearing treads on all four sides.
  • Modu-Lok has been widely used in: forge, pelletizing, and reheat furnaces, as roofs, walls, curtains, and bullnoses.
  • Merkle International’s independence from refractory manufacturers allows for flexibility in the selection of refractory quality that will fit your process and budget.

Additional Information

Merkle International, Inc. supplies structures made using the proprietary Merkle Modu-Lok system. The Modu-Lok system utilizes pre-fired refractory shapes along with metallic hangers and structural steel for support. These pre-fired shapes generally have a longer installed life and higher resistance to corrosion than plastic or castable systems. Additionally, the pre-fired refractory provides a lining of uniform density and the hanger and filled brick have structural, load bearing treads on all four sides. Additionally, support brick is placed on 4-, 8-, 12-, or 16-inch centers providing versatility in design.

Modu-Lok Suspended Roof

The Modu-Lok system has allowed the design of roofs for high-temperature applications ranging from chemical incineration to glass making; from metals smelting to mineral processing. The structural treads allow this flexibility—providing sturdy linings with maximum insulation coverage. With hangers on 8-inch centers, the Modu-Lok roof allows for 75% coverage; with hangers on 12-inch centers, coverage is 84%; with hangers on 16-inch centers, coverage is 88%. Two parent shapes are used to build the complete roof—often with a complex configuration.

Modu-Lok Walls

Modu-Lok walls are supplied in tied-back only and suspended and tied-back designs. For high-wear areas and/or taller walls, the suspended and tied-back construction is recommended. For both designs, the metallic and support steel are kept clear of, or a safe distance from the insulation. This aids cooling of the metallic and lengthens their life. Two parent-shaped are used to build the complete tied-back wall—often with a complex configuration.

Modu-Lok Bullnose

Modu-Lok bullnose construction provides roof-to-wall or wall-to-roof transition, using pre-fired refractory material. This construction is supported by the same sturdy refractory hanger design used in the roof and walls. The nose is turned with radial shaped fillers and can be designed to turn various angles. This system can be supplied for different radii, depending on the application.

MT Modu-Lok Curtains

The MT Modu-Lok constructions allow construction of independent suspended curtains, lintels, or baffles, and flat suspended covers. This construction is extremely simple, with the curtains built using only one parent shape. Curtain support brick have three full treads for better bonding and support

Metallic Support for Merkle Modu-Lok System

The Modu-Lok design locks metallics on both support brick and steel structures. Metallics are clear of insulation, which adds to service life. Additionally, metallics can be made as stampings or castings in materials to suit particular applications.

Merkle has extensive experience in suspended refractory systems, dating back to 1973. We work with our customers to find the best long-term solution for your furnace roof situation. Our staff will work with you to determine the exact refractory quality that fits your process and your budget. Materials are chosen to suit the particular application, e.g. thermal shock-resistant refractory is chosen for applications with cyclical temperatures; very dense material is chosen for highly corrosive or abrasive atmospheres.

Merkle works with its customers in the iron and steel industries and delivers what the customer needs. Our scope of supply can include structural support steel supporting our refractory system. We can also provide fabrication details for that steel, for local fabrication (saving shipping costs).

Our attention to detail has earned Merkle a reputation for customer service with its clients. In addition to supplying our innovative and highly functional products, we purchase and inspect material, and provide technical support during installation.

Download Product Sheets