We all know that non-metallic expansion joints are generally selected for desulfurization flue, mainly due to the large temperature change of desulfurization flue and the irregular expansion. However, it is not composed of a whole plate like a metal compensator, but is composed of multiple layers of fabric, which leads to the formation of a groove, which lays a hidden danger for the leakage of the compensator in the future.

 large amount of weak acid water will be accumulated in the trench during the unit operation. Once the polytetrafluoro fabric layer in the expansion joint is damaged, the weak acid water will flow from the damaged layer to the outer skin of the expansion joint, resulting in corrosion damage of the outer skin. The weak acid water will also find the leakage location, and the leakage we have been worried about will also form.

Basically, to solve the leakage of the expansion joint is to solve the problem of water accumulation in the groove. The only feasible way is to use the self-sealing and leveling process to fill the groove to seal the expansion joint as a whole, so that the acid water can not contact the expansion joint pressure plate bolts and skin, then there will be no leakage. This is also the simplest way, so that the acid water will not accumulate in the groove, and will not cause corrosion leakage of the expansion joint. Fill the groove so that the expansion joint skin will not be damaged due to the frequent buckling of the expansion joint skin caused by the change of flue gas pressure.

If it is necessary to fill the groove without affecting the expansion, it is necessary to find a kind of acid-resistant and high-elastic material, which is free to compress and expand like sponge, but also resistant to high temperature, corrosion and water absorption, and can also play a sealing role The highly elastic acid resistant tung oil gel developed in combination with the highly elastic acid resistant polyurethane sponge filler (compression ratio: 7:1) at the expansion joint between the chimney and the flue is a special case, which will not affect the expansion amount and can also play a sealing role. The upper sealing material uses highly elastic flexible glass flakes as the sealing material, and the surface uses highly elastic hybrid polymer multilayer composite material as the sealing material, The 300% elongation at break of the high elastic hybrid polymer multilayer composite ensures that the expansion joint will not damage the corrosion protection of the surface during thermal expansion and contraction. It has been constructed in more than 30 domestic appliance plants, without repeated leakage, which can ensure that the expansion joint will not be replaced for life.

By filling and leveling the expansion joint groove and expansion joint groove, the leakage and corrosion prevention problems of the expansion joint of the desulfurization flue, the expansion joint at the connection of the chimney and the flue have been successfully solved, and the corrosion and leakage problems of the expansion joint of the desulfurization flue have been solved, with a service life of more than six years.