Carbon Bonded Silicon Carbide Crucibles

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Product Code 29129
Quality and Standards IS 12847:1989
Production Capacity: Qty. Quantity : 300 M.T.
Value : Rs. 4,30,09,000
Uploaded on January 2007


Silicon Carbide crucibles are made out of silicon carbide and graphite utilizing tar pitch or other synthetic resins as bonding materials. These are highly refractory products used for melting ferrous and non-ferrous metals and alloys in the foundries due to their superb inherent properties such as good thermal conductivity, low thermal expansion, resistance to thermal shocks, resistance to wetting to molten metals, etc. when compared to clay bonded graphite crucibles. These crucibles are mostly used for melting non-ferrous precious metals such as brass, copper, nickel, chromium as well as their alloys.

Market Potential

In view of the fast development in the industrial activity in the fields of foundry and engineering, the demand for these crucibles is ever increasing particularly from mines, Railways, aeronautics, Defence Production units and other precious metals and alloys manufacturing units in the country, which, in turn, are creating wider scope for setting up new units.

Basis and Presumptions

It has been taken into consideration that the unit will work on single shift basis for 300 days in a year. The firing operations are, however, to be carried out continuously on three-shift basis till particular firing cycle is complete in all respects.

The cost of land, construction charges, cost of machinery and equipment, raw materials and consumables, salaries and wages, other contingent expenses etc. indicated in the profile are based on the prices prevailing at the time of preparation. Therefore, they are subject to necessary charges from time to time based on local conditions. The bottleneck operation of the process is the kiln capacity and firing cycle. The efficiency of the kiln and time duration of its each firing cycle entirely depends upon the design and type of kiln proposed to be used. In this case, intermittent type oil-fired shuttle kiln has been taken into consideration so as to cope with the production, which is well suited particularly for setting up a small scale unit.

It is expected that the profiles will accrue only when the unit achieves its production beyond its break-even point and is subject to the stability of costs and prices of inputs as well as demand forecast and marketability.

Implementation Schedule

The time schedule of implementation of the project in the initial stages and generation period for achieving optimum production levels in the unit etc. will be entirely depending upon the entrepreneur’s capabilities and his capacity in availing facilities from different agencies involved in the development of small scale industries. Taking an optimistic view, the following schedules have been drawn which are barest minimum requirements for successful launching of the project:


Period(in months)

Selection of site and construction 3 to 6 months
Preparation of project report and provisional registration under SSI 1 to 2 months
Availing of finances 3 to 4 Months
Procurement of machinery and equipment, raw materials and consumables etc. 2 to 3 months
Erection and Commissioning, construction of kilns, dries etc. 4 to 5 months
Trial runs and Commissioning of regular production 1 to 2 months

Technical Aspects

Process of Manufacture

The raw materials, graphite and silicon carbide with additives such as ferrosilicon- ferro managanese etc., are graded to the required sizes and mixed with bounding materials like molten pitch or other suitable synthetic resins in suitable proportions. The mixing is done in a kneading mill, namely through U-mixer when the bonding materials are in molten condition. The kneaded homogenous mixture is charged into ejection type crucible die fitted on hydraulically operated roller press. While pressing operation is carried the total mass of mixture in the mould is kept in uniform hot condition to avoid manufacturing defects while pressing. The shaped articles are left for few days for setting and cooling. The ware are inspected for laminations, cracks, etc. and then loaded into shuttle kilns for firing at 1350ºC- 1400ºC under reducing atmosphere to avoid oxidation of graphite and carbon. To create reducing atmosphere, the products should be loaded into fire boxes called saggers tightly packed with reducing agents like coke/coal dust, sometimes even graphite powder. The fired ware are unloaded from the kiln after cooling. These are inspected and cooled with a suitable glaze, which has inherent properties of protecting the crucible from oxidation at operating temperature. The glazed wares are charged into flashing furnace for the purpose of flashing the crucibles at redhot temperature utilizing coke. The finished crucibles are then suitable packed for disposal.

Quality Control and Standards

The quality of the crucibles mainly depends upon the number of heats/melts it can withstand in the foundry operations. The Bureau of Indian Standards has formulated and published the following specifications for maintaining the quality of crucibles:

IS 1748:1991 Sizes of Graphite Crucible
IS 11321:1985 Graphite for Graphite crucible
IS 12817:1989 Carbon Bonded Silicon Carbide Crucibles

Production Capacity

The profile envisages setting up a unit for manufacture of 300 tonnes of carbon bonded Silicon Carbide Crucibles valued at Rs.1.65 crores per annum.
Motive Power     80 kW.

Pollution Control

As this project is based on latest shuttle type intermittent kilns provided with oil firing system, there may not be much of pollution due to spread or emission of hazardous smoke etc.

Energy Conservation

Refractory products of this nature are mostly manufactured by the small scale units utilising coal-fired down draft kilns which are prone to emit thick smoke with Fly ash and other pollutants. Firing cycle in such kilns was also quite longer taking more time. BY introduction of shuttle kiln in the present process replacing coal-fired down draft kiln, the small scale units can be able to produce quality products in shorter firing cycle consuming less fuel and maintaining pollution free clean environment.

General precautions for saving energy particularly electricity and fuel oils are required to be followed by the unit by adopting energy conservation techniques not only to conserve and power and fuels but also to save considerable expenditure on their consumption in its own interest and also in the interest of the nation as a whole.

Energy Conservation

Each package shall be legibly and indelibly marked with name and grade of the material, source of manufacture, gross and net mass, year of manufacture and lot number.

Financial Aspects

Fixed Capital

Land and Building 4000 tonnes
Land 1000 @ Rs.4500 per 45,00,000


Area in

Rate per

Cost (Rs.)

Office block. 40 10,000 4,00,000
Raw material Godown 50 10,000 5,00,000
Manufacturing shed 250 7,000 17,50,000
Kiln shed. 100 7,500 7,50,000
Toilet 20 10,000 2,00,000
Total 36,00,000
+ Sanitary fitting and electrification @ 15% 5,40,000
G. Total 36,00,000

Pollution Control

Both raw materials, silica sand and sodium carbonate are purchased in the ready to use powder form. Only mixing of these materials in appropriate proportions is done in the batch house in the plant. Hence, dust collectors and exhaust systems are recommended in the batch house. In the melting operation, chimney of sufficient height, say 60 to 75 feet, is recommended to exit the gases of combustion, carbon dioxide from the soda ash and also volatilization of alkali oxides.

Energy Conservation

Modern glass tank furnace is recommended using furnace oil, LDO or gas firing systems. Combustion systems, for example, burners, blowers, preheating of fuel will depend on the fuel selected. Care should be taken in selecting the type and design of the furnace, refractories to be used for construction of the furnace, proper thermal insulation of the furnace walls and crown. All these factors have a bearing on the thermal efficiency of the furnace and energy conservation achieved in the melting operation. Melting operation constitutes a significant cost factor in production of sodium silicate.

Financial Aspects

A.Fixed Capital

Land and Building


Sq. Meters

Rate (Rs.)

Value (Rs.)

Land 4000 3000 1200000
Built Area
Office and Stores 100 6000 600000
Working Shed 400 4000 1600000
Raw Material Storage 400 4000 1600000
Finished goods Storage 500 500 2000000
Total 7000000

Machinery and Equipments


Imp/ Ind.

Qty. (Nos.)

Jaw crusher 150x75 mm size with 3 HP electric motor and fittings 1 No. 1
Disintegrator 350 mm size with 5 HP motor and fittings 1 No. 3,00,000
Electro/permanent magnet 1 No. 30,000
Ball mill 900x900 mm size with 7.5 HP motor and other fittings 1 No. 1,50,000
Miscellaneous tools and equipment like heating kettle, mixing showels etc.   50,000
Ejection type steel dies for different standard sizes of crucibles.   5,00,000
Vibrating screen with dust accumulator 900x600 mm with 3 HP motor and different mesh netting 1 No. 2,00,000
Weighing scales 10 Kgs. Capacity and 30 Kgs. Capacity platform type 2 Nos. 50,000
'U' Trough mixer/kneader 600x900 mm size with 7.5 HP motor and other fittings 1 No. 5,00,000
Hydraulically operated Roller press 100 tonnes capacity imported/indigenous with hydraulic accumulator, pump, pipe fittings, control valves, pressure gauges and other accessories etc.   1,500,000
Oil firing equipment such as burners-8 Nos, Blowers-2 Nos. cash with 3 HP motor, pipe line fitting-2 Nos. of preheaters, oil filters-2 Nos. storage and servicing tanks-2 Nos., pump etc. including thermocouples with pyrometers etc.   5,00,000
Testing equipment.   1,00,000
Office equipment and furniture, workshop table, racks, cupboards etc.   5,00,000
Flashing furnaces.   1,50,000
Shuttle kilns 19x10 ft and 12x10 ft with common chimney 2 Nos. 1,50,00,000
Erection, installation and electrification charges and electrical generator and bore well and water distribution system   36,00,000
Pre-operative Expenses   4,00,000
Cost of machinery and equipment   2,37,30,000
+ 10% CST cartage and Installation charges   23,73,000
or Say   2,61,03,000
Total fixed capital   3,47,43,000

B. Working Capital

Staff and Labour (per month)



Salary / (Rs.)


Supervisors 2 30,000 30,000
Supervisor 2 Nos. 20,000 40,000
Electrician & Mechanic 2 No. 12,000 24,000
Accountant.and finance personnel 2 No. 8,000 16,000
Clerk-cum-Typist. 2 No. 5,000 10,000
Storekeeper. 2 No. 5,000 10,000
Peon and watchman 6 No. 4,000 24,000
Skilled workers 3 Nos. 3 Nos. 15,000
Furnace operators 4 Nos. 3,500 14,000
Unskilled workers 15 Nos. 3,000 45,500
Perquisites @ 22% 50,000
Total 2,78,000

Raw Material (per month)

Raw Material (per month)

Value (Rs.)

Graphite imported/indigenous 13 tonnes @ Rs.50,000 per tonne 6,50,000
Silicon Carbide 9 tonnes @ Rs.35,000 per tonne 3,15,000
Ferro-Manganese and Ferro silicon 3.5 tonnes @ Rs.21,000 average per tonne 74,000
Bonding materials such as tar and pitch synthetic resin etc.5 tonnes @ Rs.15000 average per tonne. 90,000
Fire clay ball clay, china clay and other minerals like silimanite, bauxite, kyanite etc. for saggers and kiln furniture. 50,000
Misc. such as Lubricants, Chemicals etc. 25,000
Coke 10 tonnes @ Rs, 5,000 per tonne 50,000
Total 12,54,000



LDO/7.5K.L. @ 18,000/K.L. 1,35,000
Power 80x0.8x8x25x4 51,000
Water 5,000
Total 1,85,000

Other Contingent Expenses (per month)


Postage and stationery. 5000
Transport and conveyance 50,000
Repair and Maintenance. 44,000
Administrative and marketing and sales expenses (lump sum) 1,13,000
Packing materials and other consumables 20,000
Insurance 25,000
Total 257,000
Total Recurring Expenditure (per month) 19,74,000

Total Capital Investment

Recurring Expenditure for 3 months. Rs. 59,22,000
Fixed Capital Rs. 3,47,43,000
Total Rs. 4,06,65000

Financial Analysis

Cost of Production (per annum)


Total recurring expenditure 2,36,88,000
Interest on capital investment @ 12% 48,79,000
Depreciation on machinery and equipment @ 10% 11,10,000
Depreciation on Kilns @ 20% 30,00,000
Depreciation on Building @ 5% 2,07,000
Unforeseen expenses 2,00,000
Total 3,30,84,000

Total Sales (per annum)


300 tonnes of assorted sizes and shapes of Crucibles @ Rs. 1,43,000 per MT 4,30,09,000

Profitability (per annum)

Profit 4,30,09,000 - 3,30,84,000 = 99,25,000
Say 99,25,000

Net Profit Ratio


Profit x 100


99,25,000 x 100


Profit on Capital


Profit x 100

Total capital Investment

69,94,000 × 100



Break-even Point

Fixed Cost (per year)


Total deprecation 43,17,000
Interest on capital 48,79,000
Insurance 300,000
40% of staff and labour 13,34,000
40% of other expenditure 94,75,000
Total 2,03,05,000



Fixed cost x 100

Fixed cost + Profit

2,03,05,000 x 100

203,05,000 + 99,25,000


Addresses of Machinery Suppliers

Ceramic Machinery

  • M/s. Kusum Engg. Co. Ltd.
    25, Swallow Lane,
  • M/s. Batliboi and Co.
    R. P. Road,
  • M/s. National India Engg.Co. Ltd.
    7/10, Elphinston Circle,
  • M/s. Amic Industries (P) Ltd.
    10, B.T.Road,
  • M/s. D.K. Engg. Works
    8, Panchanantala,
    New Road, Balgharia,
  • M/s. Hydraulic Roller Presses.
  • M/s. New Bence Engg. Products
    Industrial Area,
  • M/s. Maiman (P) Ltd.
    B-12, Indl. Area, Uppal,
  • M/s. Quality Machine Tools
    25, Ambalal Joshi Marg,
  • M/s. Machine Tool Traders
    P.B. No. 1260,
    57A, Lingichatty St.,

Raw Material Suppliers


  • M/s. Patna State Graphite Minerals Co.
    Titagarh P.O. Orissa.
  • M/s. T. P. Mineral Industries
    Hospital Road,
    Sambalpur P.O.,
  • M/s. Lakshmi Narayan Agarwal
    Sambalpur P.O., Orissa.
  • M/s. Hindustan Graphite Refining Products Co.
    Opposite to Petrol Pump,
    G.N.T. Road, Kovvur,
    W.G. Distt. (A.P.)
  • M/s. East India Minerals
    Firyalal Building,
    Firyalal Chowk,
    Md. Road, Ranchi,
  • M/s. Aswin Mineral
    Deogarh, Baria,
    Panchamahal Dt. Gujarat

Silicon Carbide

  • M/s. Cambata Ferro-Manganese Ltd.
    42, Queen Road,
  • M/s. Ferro Alloys Corpn.
    Garividi-532, 126,
    Chipurupali Taluk,
    Srikakulam Distt. A.P.
  • M/s. Universal Ferro Alloys and Allied Chemicals
  • M/s. Indian Metals and Ferro Alloys Ltd.

China Clay, Ball Clay, Fire Clay etc.

  • M/s. Kerala Government Ceramic Works,
    Kundara, Kerala.
  • M/s. Hindustan China Clay Works
    Papinaseri, Kerala.
  • M/s. Dr. N. Gangaish
    Balakrishna Mineral Industries,
    Ramavaram, E.G.Distt., A.P.

Tar and Pitch

  • M/s Durgapur Project Ltd.
    Durgapur, West Bengal.
  • M/s. Hindustan Steels Ltd.
    Bhilai, M.P.
  • M/s. Saw Wallace and Co. Ltd.
    8/9, Thambuchetty St.,
  • M/s. Imperial Chemical Industries (P) Ltd.
    Mumbai Mutual Building,
  • M/s. Imperial Chemical Industries (P) Ltd.
    Mumbai Mutual Building,

For further information please contact

Information Manager
TIMEIS Project