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During the last twenty years, he has been working on the development, production and quality control of kiln furniture for firing a wide variety of ceramic products. He is experienced in the manufacture of cordierite or cordierite-mullite, both standard and lightweight, for firing pottery ware and sanitaryware and, in particular has developed a lightweight cordierite kiln furniture to save energy during firing of pottery and bone china. This product can be pressed into batts or other shapes.
He is also well experienced in the development and production of the whole range of silicon carbide kiln furniture (clay, oxide, silicon nitride and sialon bonded) for both fine ceramics and for technical ceramics. He has developed mullite and high alumina kiln furniture for white ware technical ceramics.
During the last two years, he has developed an advanced, dense, high strength, oxidation resistant, thin sectioned silicon nitride/sialon bonded kiln furniture product for fast firing of porcelain and bone china, technical ceramics and other engineering applications. This product is made by either slip casting, particularly for beams, or by pressure casting, which is mainly used to make flat ware.
He has other areas of expertise including porcelain, bone china and sanitaryware production. He has given technical assistance to companies in UK and Indonesia to improve their quality and yield. This has included a full examination of raw materials, froming and glazing techniques, as well as drying and firing cycles and schedules. In collaboration with Norton Refractories, technical assistance was given to a major worldwide sanitaryware manufacturer at the UK plant to improve the firing cycles by using low mass kiln furniture and hollow beams to replace the standard cordierite-mullite kiln furniture.

He is mainly concerned with advanced sialon bonded silicon carbide for kiln furniture. In the past, a considerable amount of work was done with cordierite slips for spray drying and pressing for specialised kiln furniture applications. Also work on slips for casting and spray drying of bone china and porcelain for isostatic pressing to modernise the production of these products. He has also introduced pressure casting techniques to a sanitaryware manufacturer in Indonesia to increase the productivity and general quality.

He has spent the last twenty years working on the development, production and quality control of silicon carbide product, mainly silicon nitride bonded silicon carbide for a wide range of applications, including kiln furniture, non-ferrous metals, blast furnace linings, acid domes, cyclones and wear resistance application, thermocouple sheaths, incinerator linings and firing of technical ceramics. This work has include the development of various manufacturing techniques, including pressing, vibration casting and extrusion. He has also developed slip casting and pressure casting techniques for the manufacture of advanced sialon bonded silicon carbide products for kiln furniture, engineering and wear resistance applications. This product has a thin section, high density, very high strength, excellent thermal shock resistance, high wear resistance and excellent thermal shock resistance. Apart from being used in porcelain and bone china manufacture for fast firing and automatic loading and unloading of kilns, it is used for firing sanitaryware and technical ceramics, wear resiatant applications, such as cyclones, and other engineering applications.

For the past eight years, He has spent a considerable amount of time working on monolithic products, including the development of a wide range of dense castables and ramming mixes. However, the main development work has been spent on new dry ramming products, as well as the improvement of existing products for induction furnace linings for melting both ferrous and non-ferrous metals and alloys. These developments have been based on a wide range of raw materials from alumino-silicates, such as andalusite and chamottes, to high purity fused and sintered raw materials such as white and brown fused aluminas, mullite and zircon.

He was involved with the production of refractory brick products, in general, including mid and high alumina, mullite, zircon and zirconia. In addition, he spent time working to develop and investigate refractory special shapes manufactured by ethyl silicate casting technique was examined for refractories used in the glass and steel industries. He has also had some experience of developing dense refractory products by spray drying and isostatic pressing.


Expert has over 36 years experience of building and operating various types of kilns. This has encompassed tunnel kilns, intermittent kilns and controlled atmosphere kilns, using a variety of fuels – gas, electricity and oil.
His experience has also covered a range of industries and can probably be best summed up according to industry.
Sanitaryware:
The majority of the time has been spent working with tunnel kilns for the production of sanitaryware, although some involvement with intermittent kilns for re-firing to correct glaze faults. This work has been done for major companies in UK, namely Ideal Standard, who are part of the World Standard Group and Doulton Sanitaryware, and at PT Inax International Corporation Indonesia. PT Inax is a large family owned business set up originally by the Japanese, Ina Sanitaryware.
In all cases, his role was to optimise the kiln cycle and atmosphere to ensure a maximum output and product yield. In UK, Ideal Standard and Doulton Sanitaryware operated different systems, the former being open flame tunnel kilns and the latter muffled tunnel kilns. This meant completely different firing cycles were required because the heat transfer in a muffle kiln is by radiation only, affecting the gas circulation.
At PT Inax, the major objective was to increase the yield of first quality products, which was initially 40%. This was found to be due to raw materials, amount of recycled product added and the kiln firing cycle and setting of sanitaryware on the kiln cars, i.e. the setting densities were too high.
Sanitaryware is produced in a single firing operation, viz the glaze is applied to the dried green ware and during the firing cycle the body densifies and the glaze is cured. The major changes that have occurred in the production of sanitaryware over the last few years are related to the amount of kiln furniture required. There has been a move towards low mass kiln furniture to increase the product yield and the efficiency of the kiln. This involved a change to the firing cycle and also to ensure that the kiln atmosphere was retained.
Porcelain and Bone China:
Porcelain and bone china are fired in several stages. In the first stage, the green body is fired to produce a piece which is hard enough to be handled but not necessarily dense, known as the biscuit firing. Glaze is then applied to the piece, which is then fired for a second time to densify the body and cure the glaze. Further firings are then required as decoration is applied. This is necessary because different colours are cured at different temperatures.
Biscuit firing for both porcelain and bone china are in oxidising conditions, although the firing temperatures are different. During the glaze firing for porcelain, the atmosphere varies, being oxidising up to about 900oC and is then reducing between 900oC and 1100oC (CO content = 2 – 4%). This is to produce a blue-white colouration. Above this temperature and up to 1450oC, the atmosphere is oxidising. During the glaze firing for bone china, the atmosphere is oxidising throughout the cycle.
Whilst working in Indonesia, Expert was responsible for adjusting and monitoring the firing cycles and kiln atmospheres of both tunnel kilns intermittent kilns for firing porcelain ware. The main problems relating to both the biscuit firing and glaze firing were too high a density of products on the kiln cars and lack of atmosphere control. The glaze firing was particularly bad during the reduction part of the cycle, which was very poorly controlled, ranging from being too low affecting the colour to too high resulting in carbon deposition in the glaze. This proved to be a difficult problem because of the lack of proper instrumentation.


Expert has been involved with the design and construction of both gas fired and elctrically fired controlled atmosphere kilns. He has also been involved with development and implementation of firing cycles of these kilns because this is an important part of the manufacturing process.
For silicon nitride, silicon oxynitride and sialon bonded silicon carbide products; he has designed, built and operated nitrogen/argon controlled atmosphere kilns. These electrically fired kilns have had to have more sophisticated controls because of the exothermic nature of the reaction and because the heat is applied directly to the product, unlike a gas fired controlled atmosphere kiln. The kilns were designed so that, if the rate of temperature increase exceeded that of the set point (ie the exothermic reaction started to generate its own heat in the kiln), nitrogen being injected into the kiln chamber was switched off and replaced by argon stopping the reaction. When the temperature had fallen below that of the set point, the nitrogen flow was restored. Thus the rate of reaction was controlled at all times.

Specialist Induction Refractories Ltd - developed a range of dry vibratory ramming products, as well as other monolithic products, castables, rammable, washcoatings etcCUMI, India - initial benchmarking exercise followed by improvements to the manufacturing processes, product improvements and new product developments. The products included the full range of silicon carbide refactories, high alumina and mullite pressed refractories, as well as some insulation brick.Dyson Ceramic Products - rationalisation of the range of cordierite kiln furniture to reduce the number of batch compositions and raw materials and to develop a new light weight cordierite kiln furniture. Generally, improve production techniques to reduce waste and fired losses.Lianyugang Yun Chan Special Refractories Plant, China - supply of technology, installation and commissioning of the plant, after sourcing equipment, training of personnel and setting up QC and production/process controls to manufacture silicon nitride bonded silicon carbide products.Personal - Development and patenting of a range of high strength, thin sectioned sialon bonded silicon carbide product for fast fire kiln furniture and protective body armour using pressure casting techniques.