Reliability and durability are the most critical factors when comparing different stave cooler designs. Unlike several other essential components of the blast furnace, the Stave Coolers cannot be disassembled in regular maintenance breaks. Hence, the eventual necessity of stave cooler repairs or replacements results in long furnace shut downs resulting in loss of production. Therefore, it is essential to ensure an entire campaign life for the stave coolers.
Furnace operational conditions such as high temperature events, mechanical abrasion by the falling objects, as well as cooler deformations relative to the shell are to be considered. The Stave coolers need to be designed to perform normally under the blast furnace harsh solicitations. However, frequent problems have reported, which demands maintenance shutdowns that sometimes lead to replacement of entire Stave rows.
Cecal has studied the stave operational problems in details for different steel plants and different Stave designs (rolled or cast, with or without coil, etc.). The failure modes can be categorized as follows:
1) Crack initiation in the weld that connects the pipes to the body of the Stave,
2) Leaks in the plugs which are welded to close the machined holes,
3) Deep wearing of the copper due to embrittlement,
4) Overheated parts of the copper piece in cases of insufficient metallurgical bonding between the coil and the body of the cooler.
The Stave Coolers made by Cecal are designed and manufactured to resist extreme operational conditions and avoid premature failures.
Contact us for more technical details.
