Join our team! Watlow is hiring. No experience necessary, skilled training provided, great pay, full benefits and advancement opportunities. Click here to visit our career opportunities page and apply today.

MULTICELL Heaters Power Hot Expander Forms For Titanium Parts


Forming titanium aircraft parts required a two-step process: mechanical forming at room temperature and thermal-conditioning in a furnace. The recent increase in demand for titanium parts has created a demand for faster cycle times.


A new hot forming hydraulic expander permits simultaneous forming and thermal conditioning of titanium aircraft engine casings. By using Watlow® multicell heaters and ceramic insulation to keep temperature profiles uniform along the part, the expander can maintain tighter control of the part's physical dimensions.

Three MULTICELL heaters, operating at 1350°F (730°C), slip-fit into holes bored into each of the hot expander's dies. A closed loop electronic control system monitors signals from thermocouples in the three zones. This is a departure from previous hot expanders which provided heat via a single wound filament located near the center of the part. By applying heat to three zones along a part instead of one, distortion due to varying rates of thermal contraction is kept to a minimum.