Karya Unggulan Iptek Anak Bangsa

On HATEKNAS (Hari Kebangkitan Teknologi Nasional 1995 – 2015), Ministry of RISTEKDIKTI gave 20 Awards "Karya Unggulan Iptek Anak Bangsa" in Jakarta. One of the award recipients was Mrs. Kuntari Adi Suhardjo, Mr. Hafid, and Mr. Surasno with their research Insulated Rail Joint from Composite Materials as A Substitute to Imported Rail Joint.

The insulated rail joint (IRJ) is an instrument that connects one rail road to another  and a safety critical component of the rail track infrastructure. The IRJ provides two functions, i.e. as an insulator and as structural stability to the track. As an insulator, IRJ electrically isolates track into discrete section to facilitate signal control. As an rail joint, IRJ bears the static and dynamic weight/force of the train. Therefore, an IRJ is required to posses a great strength to enable safe passage of wheels across the joint.

Until now, PT KAI still uses an imported IRJ. It is because the local IRJ product does not have steel structure and it has a short usage time. The objective of the research is to produce IRJ product made from epoxy resin and fiberglass composite which has steel structure, so it can meet PT KAI's technical specification through choosing the suitable material, optimized process, optimized structure design and manufacture. The target is to increase the growth of small-medium enterprise in the field of composite industry, to open new line of work, and to minimize import dependency. The factor that influenced the manufacturing process of an IRJ is the curing process (matrix): temperature, pressure, and time. Epoxy resin can be polymerized at room temperature, but it needs 24 long hours. To speed the production time, they use an autoclave device where the temperature, pressure, and curing time can be arranged and controlled. All IRJ variance has a very good insulator characteristic to electricity whether it is in dry or wet condition.

At first, they made IRJ from polyesther resin, fiberglass and kevlar with selling price around 2.8 million rupiahs. However, this price is still quite expensive. Then, they kept doing research and found that using composites from epoxy resin and fiberglass result in cheaper IRJ, which can get the selling price Rp. 1.900.000.- per set after tax. It is much cheaper than the imported IRJ with selling price Rp. 5-6 million per set. PT KAI needs IRJ more or less 160,000 pcs per year for only in Java island railways. So, with this technology, the country budget can be saved 160-240 billions rupiah per year.

The research has bee patented in Indonesia with patent number P0034451 on 19 September 2013. This innovation is also appreciated by Ignatius Jonan, President Director of PT KAI at that time and will be manufactured by Balai Yasa Kereta Api Indonesia.

Kuntari Adi Suhardjo

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