Fives has successfully put forward more than 16 annealing lehrs into operation for a photovoltaic (PV) glass manufacturer in China over the last few months.

The annealing lehr for extra-large glass ribbons, features Fives' technology and engineering efforts of the local team in China, has a production capacity above 300 metric tonnes per day.

Lehrs were designed, supplied and commissioned by Fives Stein Metallurgical Technology, Shanghai, a Fives’ subsidiary in China.

Continuous annealing

The annealing lehr is not sophisticated equipment, but it’s the key to slowly cooling glass to relieve internal stresses after it was formed.

Fives has proprietary expertise for the hot air continuous annealing process to accurately control the cooling curve at every point of the glass ribbon – longitudinally and transversally.

Annealing lehr key features include:

• Optimised heating to thickness and width requirements

• Up to seven transversal cooling zones for smoother control

• Specific solution for high-capacity production of ultra-thin glass

• Accurate thermal balance calculation and proportional control system

Fives has partnered with PV glass producers in China for more than 20 years and has supplied more than 100 annealing lehrs.