HPH® Bell-type Annealing Furnace for Nonferrous Strip
LOI Thermprocess, with its predecessors Matthias Ludwig and Nassheuer, has been building bell-type annealing plants for more than 60 years. Throughout the world, more than 8500 LOI annealing bases have been installed. About 5000 of these bases operate with HNx controlled atmospheres. More than 3500 bases use HPH® annealing technology, with a proven atmosphere of pure hydrogen.
Bell-type furnaces are the most economical, most flexible alternative for the heat treatment (homogenization and recrystallization) of non-ferrous metals. Bell-type annealing plants are suitable for the treatment of all types of rolled nonferrous products including strips, foils, wire, and wound tubular products.
Coils of copper-based alloy products are heat treated in a controlled atmosphere. The atmosphere used depends on the specific alloys and the annealing process which is required. The gases, which are available, include pure hydrogen, nitrogen or mixtures of the two. For the homogenization of certain alloys, nitrogen is selected as the atmosphere gas for economic reasons as hydrogen is more expensive and offers no advantages for this process.
In contrast, nonferrous metals are normally recrystallized using pure hydrogen as an atmosphere gas in order to obtain a bright metal surface by way of the high chemical reducing potential of the gas. In addition, the high thermal conductivity of hydrogen enables considerably higher heating and cooling throughputs compared to nitrogen.
Value for Money
- Solid annealing equipment design
- Low operational costs
- Excellent temperature uniformity
- Very uniform mechanical properties of the annealed wire
- High convective heat transfer
- High efficient burners
- Individual recuperators
- TÜV proven safety strategy
- Sophisticated process control
- O2 concentration monitoring possible
- Long service life
- Sturdy cast diffusor system
- > 60 years of experience in Bell-type Annealing
- > 8,500 annealing bases worldwide (>3,500 HPH®)
- Selection of alternative cooling systems
- Fully automated control system
- Various software modules for optimization
Value for Money
- World's first fully automated BAF plant
- HPH®-Flameless combustion technology