Your Water Seal Trough Problem

Wire mesh screens around your bottom ash hopper has been an industry standard practice since the 1990’s. This commodity based product is a short lifecycle, sacrificial device used to protect your water seal trough, dipper plates, seal plates, and seal skirt. However, wire mesh screens present many challenges to your operations team. At installation, wire mesh is 56% open, providing little protection to the seal trough from radiant heat. Flexibility, touted as one of its best features, is lost shortly after installation as the openings in wire mesh become catch points for ‘ash cake’, becoming hard and inflexible like concrete. Wire mesh, weighed down with ash cake, begins to tear off the seal trough wall.

Refractory poured castings, an original OEM type of expansion joint protection, are extremely heavy with no flexibility to absorb clinker impact. Refractory chips and falls out of the castings quickly after installation, leaving your seal skirt and trough unprotected. Once screens or castings have failed, your seal skirt is directly impacted by radiant heat from the boiler and bottom ash hopper.

Maintenance shutdowns are typically extended to repair or replace damaged wire mesh screens or castings. Longer outages result in higher labor costs and replacement material expense.

There should be a better product for the protection of the entire expansion joint in a bottom ash hopper.