Pukyong National University

The new technology what values 600 billion won broke stereotype maintained for 70 years in the industrial world.
- The research team in Pukyong National University developed high-classed welding technology what has 2.5 times better productivity.

Korean research team developed new technology which can dramatically raise productivity of steel pipe which is key component of plant industry.

The research team of Cho Sang-Myung who is a professor of the department of material science and engineering developed the new clad welding technology on January 27 which has 2.5 times better productivity compared with the existing clad welding which is used world-wide.

The clad welding is covering special alloy thinly on the inside of steel pipe with heat. It prevents rust and wear and resists heat. The steel pipe is a key component of plant industry and used widely in the various fields such as ocean, petrochemistry, electricity generation, and transportation of crude oil.

The new technology is from breaking the stereotype. It started from changing the style of welding rod which is used for the past 70 years in the industry. They invented new style of the rod as changing the existing shape looked like thin-curved wire into the C style which has dented furrow in the middle of rod.

After conducting experiment with the new C style welding rod, they found that the speed of melting the rod down and deposition on the inside of steel pipe has been improved as 2.5 times than existing rod in the same condition. It usually took one week for clad welding of one steel pipe which has 30cm diameter and 12m of length, but now we can make 2.5 pipes for a week.

It is because the C rod get heated more than the circle one, so it is melted faster. The reason that researchers can find this simple fact is because of scientific proof that argon arc which can be out when people are welding is plasma stream which means that the lump of heat coming down from the top. The heats of arc from the top get piled up in the dent, and that makes the roe melted faster. The arc heats in the existing circle type rod were treated as stagnant object just releasing radiant heat.

One steel pipe costs around two million won. After processing of clad welding, the price jumps up till forty million won. In Korea, we export a steel pipe to other countries and import again after processing of clad welding, so we waste huge finance on that.

"The global demand of pipe for plant will be around 80000km and 30 billion dollar for ten years from now. The new technology what we invented will make values around 300 billion won of import-substituting effect and 500 billion won of export scale," professor Cho said.<Pukyong Today>