Customised Carbolite raises the roof on an advanced ceramic materials production process

Facing the introduction of a new manufacturing process to its Gloucester production facility the abrasives division of a major multinational manufacturer of advanced ceramic materials needed to rapidly replace some large raised hearth furnaces that had reached the end of their useful lifespan.

Carbolite was called in to meet the challenge and the UK’s largest manufacturer of laboratory and industrial furnaces and quickly realised that a rapid implementation of a well trusted design was crucial for the abrasives manufacturer to ensure the new manufacturing operation had the best chance of starting on schedule.

The application requirement called for a rapid cycling batch furnace capable of de-binding and sintering 100kg of graphite matrix with a ceramic powder inclusion at up to 1000°C, under a reducing atmosphere of nitrogen and hydrogen.

Carbolite’s solution features a design that has been built for export customers several times before at the company’s factory in the UK’s Peak District.

Unlike previous occasions the application did not require an afterburner but it was vital that a 600 x 1200mm Inconel 601 retort was used to contain the nitrogen/hydrogen atmosphere.  Inconel-coated catch trays were also added to the retort to capture any process material that might fall from the load. Because the nitrogen/hydrogen reducing gas was pre-mixed and below the explosive limits for hydrogen it was not necessary to provide the gas safety system that Carbolite would normally provide when working with higher concentrations of hydrogen.          

Uniform heating of the load was critical so a 3-zone control system compatible with the aerospace standard NADCAP 2750 D, Class 2 was installed that offered   optimum control uniformity. Each of the three zones was equipped with its own independent over-temperature protection device and at the heart of the control system a sophisticated multiple segment programmer system was fitted that was able to recall multiple separate, process specific, temperature profiles.

To enable fast turn-around times between process batches, a wheeled load handling device featuring a jacking lift mechanism was included in the specification.  Faster cooling of the retort at the end of the process was achieved using an electrical lifting device which progressively raises the highly efficient, low thermal mass, insulated roof of the furnace to allow heat to escape more quickly.

Carbolite, which is highly experienced in the design and manufacture of a wide range of de-binding furnaces, with or without after-burners and catalytic converters, is also experienced in offering custom designed modified atmosphere control solutions.

About Carbolite
Established in 1938, Carbolite has over 60 years of experience in the design & manufacture of electric laboratory & industrial furnaces, laboratory & industrial ovens & incubators.
During this time, Carbolite has established an enviable reputation for its ability to design and manufacture quality products for standard & special applications for laboratory, pilot scale & industrial applications. Today, Carbolite equipment has become the standard against which other heat processing equipment is measured.

For sales and technical information contact:

Carbolite
T: + 44 (0) 1433 620011
Email: info@carbolite.com
Web: www.carbolite.com