Present Status of Foundry Industry in Sri Lanka and Measures to Develop the Industry

By Eng. Dr. Indika De Silva

The foundry industry in Sri Lanka dates back to as far as the second century BC and still in its developing stage. The modern ferrous industry based on the cupola furnace was developed in Britain during the eighteenth century and imported to Sri Lanka in the latter parts of the nineteenth century. Foundry Industry is an important feeder industry for the light engineering product sector; it supplies parts and spares for machinery and equipment specializes in tea, rubber and oil machinery parts. In addition to supply of vital components of marine engineering and turbine bearings, it also supplies a wide range of directly exportable finish metal products. Local foundries have the production capabilities of grey iron casting, ductile iron casting, aluminium, brass and steel castings.
Even though Sri Lanka is trying to establish as an industrialized country as a nation since early 90s it has not been a success. The present government too focuses on developing regional economy greatly. In that perspective, light engineering product manufacturing sector especially the SMEs (Small and Medium Scale Enterprises) have a bigger role to play by converting their processes towards green while minimizing importation of foreign raw material and launching new businesses to increase value for local raw materials while focusing on foreign trade markets. After introducing the open economy policy to the country, traditional light engineering product manufacturing industries forced to deteriorate. Rapid urbanization and introduction of similar products with low cost materials as well as with advanced technologies from other countries are the main causes for this deterioration. Though their theoretical knowledge has been degenerated significantly with the time, they managed to cater the unstable situation.

Questionnaire Survey

A structured questionnaire was prepared for the survey, and detailed discussion and foundry visits related observations also taken into account in the analysis. Sample of 200 foundries was selected for the survey including all foundry categories located in various areas in Sri Lanka.The main objective of this work is to get a cross sectional view of the present situation of the local foundry industry.

The main areas covered in the investigation is given as below;

1. Distribution of brass, bronze, cast iron and aluminium foundries
2. Quality of the products
3. Local and international market
4. Raw materials and Manufacturing processes
5. Government and private sector contribution to develop the industry
6. Health and safety

Distribution of Major types of Foundries in Different Areas

Most of the foundries in Sri Lanka are aluminium & brass foundries and there are few numbers of cast iron & bronze foundries. It is identified that most of foundries are scattered in the districts of Kandy, Colombo, Gampaha, Kurunegala, Matara& Hambantota          (Figure 1). In Colombo district, foundries are scattered in Malembe, Kaduwela, Athurugiriya and Ranala areas and they produce mainly aluminium products such as pans, jugs, and spare parts for gas cookers, kettles and string hopper machines etc. Kadawatha, Kalaniya and Kiribathgoda are the regions that foundries are located in Gampaha district and most of these are aluminium foundries. According to Figure 2 most of the foundries in Sri Lanka are aluminium foundries and there is little number of bronze foundries.

Ceylon Heavy Industries & Construction Company Ltd (CHICO) & Industrial Development Board (IDB) are the main large-scale cast iron item producers in Sri Lanka. They produce brake shoes, rubbing blocks, rollers, bearing blocks and different types of machinery parts. brass industry is mainly spread across the central province and in some isolated villages in the rest of the island. Especially this industry is concentrated in Pilimathalawa area and those brass foundries produce betal trays, kendies, vases and oil lamps etc. In addition to this, there is another village created by the government in 1965 near to Kandy called Kalapuraya for traditional handicraftsmen at that time. Later this village was expanded in two phases and currently consists of about 100 families and significant number of them involved with Brass industry. In addition, there are several manufacturers scattered in several other areas in the island who practice this industry. The foundry industry is existed from generation to generation in above mentioned regions and therefore the traditional technology and skilled foundrymen are bonded with these regions.

Figure 1: Analysis of response of the districts

Figure 2: Analysis of types of foundries

One of the major reasons for establishing foundries in certain regions is availability of special types of soils, sands and clays which can be used to prepare suitable moulding sand in these regions as natural resources. As an example, granite powder is used as the moulding sand especially in Kiribathgoda, Malambe, Athurugiriya and Kaduwela regions as it is extensively available in these regions. Around 60% of foundries scattered in Colombo and Gampaha districts. That is due to the huge market capacity and most of the foundries which produce light engineering products for international market are scattered in these two districts specially in industrial zones.

Quality of the Cast Products

There is an urgent need to enhance the quality of foundry products as it is not up to the competent level with international market. The quality of a product is closely related to the customer requirements and quality parameters depend on the type of product. As an example, the most significant quality parameter of the ornament castings is the surface finish.  However, in automobile parts and machinery parts, strength & hardness are the significant quality parameters.

Figure 3: Factors affect the defects of sand castings[1]

Analysis of Casting Defects identified in the Survey

Figure 4: Analysis of casting defects

Technological Needs Assessment

Though the other industries in the world have already transformed to semi-automation and some even transformed to fully automation, the traditional brass industry still practices the traditional manufacturing process. Unawareness of the exact technological process, unavailability of trainings and awareness programs to improve this industry are encountered as the main causes for the prevailing gaps which have been raised technologically. Urging requirements are there to mechanize some of the critical operations which are known to be non-ergonomic. Properly designed trainings are required for these traditional craftsmen to undergo technological phase lift. Preparation of the green molds in the traditional method, insufficient knowledge to calculate and assign the required number of risers and runners, unawareness of the importance of reinforcements in mold building and the cooling rate are determined as the main causes for the explosion of molds.  It is also revealed that these craftsmen do not hold any knowledge on techniques for metal pouring and handling critical areas like round edges, corners, drafts, etc. during the casting stage.[2]

The common method of reconditioning moulding sand is by hand sieving and the use of a mix muller is rare. In most small foundries the mould boxes are seldom clamped together, but weighted down from the top to avoid thermal expansion [3]. Several medium size foundries use steel moulding boxes with dowel pins and clamps. In addition to the use of moulding boxes, floor moulding is also extensively practiced. The situation of the non-ferrous foundries scattered over the country is also far from satisfactory. Also, the furnaces used are oil fired type and the efficiency is not in a satisfactory level as they are designed without theoretical considerations. In most small foundries the pouring temperature is not measured and worked only with eye estimation, and in some cases the temperature comes down during the handling process which causes casting defects. The gating system is prepared on the skill and experience of the foundrymen without any theoretical background[4]. The castings made are kept overnight and removed from the moulds. The foundrymen remove sprues, runner bars, in gates and risers by breaking it with hammer blows. In most foundries, they are not cut off by a band saw. The casting fins and other rough surfaces are ground off using angle grinders or in a pedestal grinder. Shot blasting facility is not available in most of the foundries in Sri Lanka. Lack of overall metallurgical control of the casting process has resulted in a very high number of rejects. Quality inspection is mostly only visual, any form of non- destructive or metallurgical tests are rarely carried out, the quality being often revealed at the machining stage[5].

Selection of Suitable Foundry Sand

Figure 5: Analysis of locally used moulding sand types

Large proportion of castings especially the aluminium castings are made using granite powder as the moulding sand (Figure 5). Unfortunately, the quality of the castings is not in the required level. This deficiency may be due to lack of knowledge on properties of moulding sand such as permeability, clay content, green compression strength and AFS (American Foundrimen’s Society) sieve number etc., and the testing methods of these parameters. Normally small-scale brass foundries use a mixture of tile dust and granite powder as a moulding sand.  Few foundries (around 10%) use mixture of local silica sand and bentonite to gain better quality. However, the price of bentonite and transport cost are too high for those foundries. Therefore,it is required to develop a locally available naturally bonded sand or sand -clay mixture which can give better quality with a low cost.

Measures Required to Develop the Industry

Government and Private Sector Contribution

Though there are number of government authorities such as Ministry of Traditional Industries and Small-Scale Enterprise Development, Industrial Development Board, National Design Centre, Jathika Shilpa Sabha etc., still there is no effective mechanism to identify technology requirements to enhance the productivity and competitiveness as well as phase lifting of the industry towards expanding the local and international market.Unidentified market for the innovative crafts in the industry is a prevailing constraint, which has become a barrier for the innovation and creativity of the traditional craftsmen. Adequate steps have to be taken by the corresponding local ministries to encourage these innovative crafts[2].

It is also clearly noticed that the low educational level and negligence on health and safety practices have prominent influence on the sustainability of the industry. It is observed that the traditional craftsmen do not wear any preferred safety equipment and also do not practice any safety regulations. Since, the craftsmen use thermal furnaces like cupola and fuels to melt brass melting emits considerable amount of carbon dioxide, carbon monoxide etc., which can affect the atmosphere and the surroundings. There are immediate needs to improve health and safety practices in the industry, which has to be elicited by the Ministry of Health, Sri Lanka[2]. Insufficient investments and inability to obtain bank loans for the improvement of the industry is also a noticeable constraint. Though few local banks provide loan schemes, those schemes with high interest rates and strict guidelines have reduced the tendency to obtain loans.

Workshops, Seminars and Research on Foundry Technology

The fundamental problems of the foundry industry can be identified as the lack of training of persons at all levels, dearth of metallurgists and lack of investments. The Ministry of small & rural industries, Board of Investment (BOI) & Export Development Board (EDB) are the principal government agencies responsible for industrial activities in Sri Lanka. Hence, they can implement a proper procedure to solve the above mentioned fundamental problems. Workshops could be organized as a part of this procedure with the support of universities. The institutions such as Universities, Industrial Technological Institute (ITI) and National Engineering Research & Development Centre (NERD) can play a predominant role in promoting the technology used in foundries. Especially research work should be carried out to;

• enhance the efficiency of the melting process.
• develop cost effective furnaces with reduced air pollution.
• invent sand-clay mixtures which gives sand castings with improved quality.
• find the possibility of utilizing the metal slag and dust collected in foundries for manufacture of concrete mixtures and bricks.

The higher price of coke, furnace oil and gas is one of the major problems that foundry industry faces today and the involvement of government to solve this problem is essential.

Foundry Development & Services Institute (FDSI)
The Foundry Development & Services Institute (FDSI) has been established and is managed by the private sector foundry industry in Sri Lanka. The FDSI efforts are aimed at improving the productivity, quality and the market share of the foundry sub-sector and upgrading the castings to international specifications. Although the membership of FDSI is more than 50 companies, at present there are only about 20 companies regularly participate in meetings [6].

Activities of FDSI [7]

• Train people in foundry process on safety and environmental requirements
• Assist industries on selection of machinery and identification of metals
• Conduct seminars for industries
• Organize visits to foundry exhibitions and industry familiarization
• Coordinate with government institutes universities on foundry industry requirements.
• Assist members to market their products locally and globally
• Protect local raw materials and Monitor global and local raw material prices
• Publish foundry information and Study papers

Expanding the Local and International Market

Survey results revealed that local demand is extensively directed towards the ornaments and machinery parts. However, the demand for kitchen equipment, door & window fittings are in a satisfactory level (Figure 6). At present this industry indirectly contributes to the tea and rubber exports by supplying machinery components to these industries.

Figure 6: Analysis of foundry items

Studies undertaken in Sri Lanka show that the efficiency and competitiveness of the local light engineering industry is in a satisfactory level relative to the international level [6]. The country produces products such as precision tools, moulds and electrical enclosures and manufactures high quality water pumps and agriculture machinery for the local market. In Sri Lanka some customers pay attention towards the price rather than the quality of product & they are willing to buy products which are imported from India & China. Our major export products are Precision tools, Molds, Steel bars and sheets for construction Industry, Steel furniture, Automobile parts, ornaments and Cutlery. Those are mainly exported to India, Germany, Maldives, Singapore and United states.

Figure 7: Composition of Exports, Jan-Dec 2016, Sri Lanka Customs

In general, it is very obvious that the traditional brass products do have an appreciable market locally. But due to less exposure to the foreign market and poor government supports local traditional craftsmen are not able to hold on strongly on foreign market. It is also revealed that the government handicraft sales centres like Laksala and Lakpahana played vital roles in marketing their brass products few years back. But with the time revolution Laksala and Lakpahana have reduced the number of orders and also handled poor settling plans which have drawn them with some economic burdens. Also, the traditional craftsmen reveal that their profit margin is determined by the intermediate sellers in the market.[2]

It is also observed that the local traditional brass manufacturing industry in Central Province, Sri Lanka has not exactly identified the market requirement of Northern and Eastern Provinces of the island. Number of Hindu temples in Northern and Eastern provinces import brassware from India. So, there are opportunities to extend the market, if the traditional craftsmen take the requirement of Hindu temples into their consideration.[2]

Novel Foundry Sand Formulation

The structured questionnaire survey results revealed that one of the most significant quality parameters of the brass casting is the surface roughness. According to the survey results few foundries (around 10%) use mixture of local silica sand and imported bentonite to gain better surface quality. However, the price of bentonite is relatively high and therefore the production cost is high especially for small-scale foundries. In addition, the government should spend a considerable amount of funds annually to import Bentonite. The Author developed a set of sand-clay mixtures using locally available natural sand and clay, which can replace the expensive bentonite to produce brass castings in an economical way enhancing the surface quality[8]. Furthermore, patent certificate was obtained for this novel foundry sand formulation(Patent No. 16069).However, this is still utilized in few local foundries due to lack of awareness.

Raw Material and Machinery

Raw materials have become one of the most significant issues because of the scarcity for the materials and the prices which are raising day by day and finally make no profit at all for the craftsmen. Today the production of brass is done by few foundries as the price of the pure Cu and Zn ingots is unbearable for the local foundrymen. Therefore, most of foundries use brass scraps, which has certain amount of other metals such as Al, Fe & Sn etc and results in lower quality of product. It is noticed that there are no standards are being imposed by the government to ensure the quality of these raw materials.[2] Earlier Sri Lankan government has provided metal scraps with an appreciable quality in an affordable price. Since, the government has stopped the supply recently, these local manufacturers must go behind the local importers. Poor quality and fluctuating prices set by these importers have been some of the critical issues which have demotivated the craftsman to sustain in this industry in future.

Modern day manufacturing industry has developed rapidly and even local manufacturers quickly adapting latest technologies such as CNC, 3D printing etc. the traditional Brass industry still survive with centuries ago outdated obsolete technology which makes that industry less efficient and less competitive as well.[2] It is required to provide sufficient training on mould fabrication using CNC machining with SOLIDWORKS and Solid CAM software for 3D modeling. Surprisingly these traditional craftsmen do not consider energy as one of the predominant cost components since they have been using comparatively cheap energy source of heavy furnace oil (HFO) for burners and it is very cheap when compared to the raw material they consume. Therefore, they do not pay much attention towards combustion efficiency of the burners. This indirectly escalates the cost of manufacturing. In addition, this leads to the increase of health issues, since many of them do not use proper stacks for the burners while getting exposed to the exhaust fumes. [9] In addition, excessive emissions contribute to the environmental pollution as well. One major concern is the effective time they use the furnace and the space they have permanently allocated within the sheds. This has made the layout of the working ambiences much complicated affecting the handling operations and as well as the health and safety issues. Even though proper insulation exists in the design it has become inefficient due to the way they practice it. Therefore, local brass industries also in need of an efficient furnace which can manage the emission factor and safety hazards as well.

The high cost of the moulds is one of the major issue that foundry industry faced today. Therefore, they focus on low cost but not 100% desirable materials for mould manufacturing. Mild steel and cast iron are extensively used for moulds utilized in die casting process. Another major concern that mould & die makers faced today is the unavailability of a well-organized facilitation and development centre to address the burning issues in the sector which could not be taken up as individuals. The Mould & Die Makers Association together with the Ministry of Industry & Commerce and the Department of Mechanical Engineering, University of Moratuwa identified the key issues and were able to launch a ten-year development plan in 2010[10].  The centre provides the service of design and manufacturing of moulds required to local industry using modern technology with professional backup. In addition, they are engaged in Training programs for;

• Design of Dies, Moulds, Press Tools, etc
• Innovative Product Design.
• CNC Part Programming and Machining.
• CAD/CAM/CAE related applications

Novel Method for Measuring the Surface Roughness of Castings

Generally, the most significant quality parameter of the castings such as ornaments, door and window fitting etc. is the surface roughness. Presently the surface roughness of the castings is measured by using JISBO659 surface roughness gauge. But it is not an advance scientific method as the sensitivity and the accuracy of this method is not up to the satisfactory level. The most common and standard method used for measuring the surface roughness is stylus profilometry (Surtronic 2). But this method is not suitable for measuring the surface roughness of castings with complex shapes. To overcome these restrictions, a research group at university of Moratuwa developed a non-contact method to measure the surface roughness of castings using ultrasonic echo amplitude technique with improved accuracy and minimized cost-Patent No: 17378[11]. In this novel method, surface roughness is given as a function of attenuation (Attenuation is the term used to describe this condition of energy loss) due to the surface roughness of casting.

References

• Clegg A. J., Casting Processes, Cast Metals Federation, National Metal Forming Centre, U.K., 1998.

• Chanjief C., Herath S.A., Jayasinghe R., Gowrynathan J., Kulatunga A.K., Dharmawardhana M., Ekanayake R.E., “Technological Needs Assessment of Traditional Brass Industry to Enhance the Productivity”, Proc.International Conference on Industrial Engineering and Operations Management, Dubai, UAE, 2015.

• Tittagala S.R., Welding, Casting & Metal Forming Country Report-Sri Lanka, University of Moratuwa, Moratuwa, 1998.

• Jayawickrama H.M.M.M, Dharmawardana M., Kulatunga A.K, Karunarathna K.G.S.P, Osaditha S.A.U., Decoupling Growth from Resource Use Enhancement of Productivity of Traditional Brass Manufacturing Industry using Sustainable Manufacturing Concept, Proc.13th Global Conference on Sustainable Manufacturing, Procedia CIRP 40 (2016) 562 – 567.

• Fernando B.S.N., Foundry Industry in Sri Lanka. Country Report, Industrial Development Board (IDB), 1999.

• De Silva G.I.P. and Munasinghe N., “Quality Enhancement of Foundry Products-a Case Study of Foundry Industry of Sri Lanka”, Engineer, VOL:XXXVIII, NO:01, Institution of Engineers, Sri Lanka (IESL), 2005.

• Foundry Development & Services Institute (FDSI) official web site http://fdsi.lk/about/, Visited, 14th March 2018.

• De Silva G.I.P. M.PhilDissertation: “Enhancement of Surface Quality of Brass Castings Cost Effectively Using Naturally Available Sand and Clay Available in Sri Lanka”, University of Moratuwa, 2006.

• Wijewardana D.L.D.K., Gunawardena P. and Cooray M.N.R., A study on Die and Mould Manufacturing Industry in Sri Lanka, Project SMED, 2003.

• www.diemouldsl.com, Visited, 16th March 2018.

• De Silva G.I.P. and Munasinghe N., “Surface Roughness Measurement of Castings using Ultrasonic Echo Amplitude Technique”, Proc.11th Annual Symposium, Engineering Research Unit (ERU), University of Moratuwa, 2005.

 

Eng . Dr. Indika De Silva