NIPPON STEEL Corporation: Innovating with advanced technologies

By Joanne McIntyre & Kiyo Ichikawa, Stainless Steel World

Nippon Steel, Japan’s largest steel manufacturer and one of the leading global steel producers operates manufacturing facilities in Japan and over 15 countries worldwide. Over the past twelve years, the company has experienced significant transformations. In 2012, it merged with Sumitomo Metal Industries, followed by a merger with Nisshin Steel in 2020, at which point it adopted its current name.

The Nippon Steel Group focuses on four key business areas: engineering, chemicals and materials, and system solutions, with steelmaking at its core. Aspiring to be the “World’s number one steel manufacturer in terms of comprehensive capabilities,” the Group leverages state-of-the-art technology and manufacturing expertise. It contributes to societal development by delivering high-quality products and services.

Nippon Steel directly oversees the Group’s domestic steelmaking business, which remains its primary operation. The company boasts some of the world’s most advanced product and solution capabilities, honed through long-term relationships and consistently meeting the stringent demands of its customers.

Adapting to change

Nippon Steel’s operations are categorised into steel pipes, thin plates, thick plates, steel bars and wire rods, building materials, and transportation and industrial machinery. The company’s steel pipe division is particularly competitive on a global scale, especially within the energy sector. The company has a longstanding tradition of research and development aimed at meeting the diverse needs of its customers and anticipating societal trends.
“Recently, we have navigated various crises driven by changes in the external environment by proactively anticipating change and reforming ourselves. As a world-class steel manufacturer, we remain committed to leading the future of steel while maximising corporate value,” stated Mr. Matsuo.

Oil refining 347AP, 347AlPha, 317AP

Nippon Steel specialises in manufacturing high-quality alloys designed for demanding applications such as oil refining. In refinery areas operating at high temperatures, such as heavy oil thermal cracking units, materials must exhibit both sensitisation resistance and high-temperature strength. 347AlPha (UNS No. S34752) (low C 18Cr-11Ni-3Cu-Mo-Nb-B-N) has been specifically developed to meet these stringent requirements. Polythionic acid-stress corrosion cracking (PTA-SCC) poses a significant challenge in petroleum refineries, necessitating materials with high sensitisation resistance. TP347H and TP321H, stabilised through heat treatment to precipitate fine NbC and TiC within the grains, have been effectively utilised in combination with post-weld heat treatment.

Conversely, 347AP (18Cr-11Ni-Nb-N, ASME Code Case 2196-4) offers excellent sensitisation resistance without the need for post-weld heat treatment, attributed to its low carbon content. Additionally, 347AP demonstrates a higher maximum allowable stress compared to conventional low-carbon austenitic steel TP304L (ASME, SA-213). However, in high-temperature applications such as heavy oil thermal cracking units, in addition to sensitisation resistance, even better creep strength is required. Low-C 18Cr-11Ni-3Cu-Mo-Nb-B-N steel (UNS No. S34752) was specifically developed to meet this demand. The creep strength of S34752 is significantly higher than that of 347AP and TP347H. S34752 is also successfully applied to high-temperature applications other than refineries, such as Steam Methane Reforming (SMR), a technology that mixes natural gas with super-high-temperature steam in the presence of a catalyst, causing a chemical reaction to produce carbon monoxide and hydrogen.

317AP (UNS No. S31740) was developed specifically for use in distillation towers in oil refineries. The previously used material, 317L, often faced challenges with polythionic acid-stress corrosion cracking (PTA-SCC) in environments susceptible to naphthenic acid corrosion. To address this issue, 317AP was engineered to enhance PTA-SCC resistance while maintaining its corrosion resistance against naphthenic acid. This alloy has been successfully implemented in the United States and shows promise for use in renewable diesel and sustainable aviation fuel (SAF) plants, where similar organic acid corrosion occurs. Data on its performance in these new applications is currently being collected.

Invar alloy

Invar alloy, known for its exceptionally low linear expansion coefficient, is designated for cryogenic applications, including liquefied hydrogen and LNG. Nippon Steel stands as the sole manufacturer globally capable of producing seamless Invar alloy. Additionally, through collaboration between Nippon Steel Stainless Steel and Nippon Steel Stainless Steel Pipe, Nippon Steel group can supply large-diameter welded Invar alloy pipes. Governments worldwide are working towards achieving a carbon-neutral society by around 2050. However, during this transitional period, demand for fossil fuels is expected to persist or even increase. Specifically, the demand for natural gas is projected to rise due to its relatively low CO2 emissions compared to other fossil fuels.

Nippon Steel’s High Alloy OCTG (CRA) are engineered to perform under the most challenging conditions. These products excel in high-temperature, high-pressure environments, particularly in natural gas reservoirs with high concentrations of CO2 and hydrogen sulfide.

“Our company has the ability to manufacture everything from stainless steel sheets to pipes to bar and is one of the main producers of products for this highly demanding sector,” explains Mr Nakajima. “We will contribute to the global effort to reduce carbon emissions through the supply of our products. A good example is the growing number of orders we are receiving for Carbon Capture and Storage (CCS) applications, and in particular, for duplex stainless steel.”

Technology development headquarters

Nippon Steel boasts one of the largest research and development teams in the steel industry, comprising approximately 800 R&D professionals. “To achieve our goal of becoming the world’s leading steel manufacturer in terms of overall capabilities, we strive to contribute to societal development by driving R&D that anticipates customer needs and addresses social issues. Our approach is structured around three key pillars,” explains Mr Fujita. “These are:

1. The challenge of carbon neutrality,
2. Strategic product development to achieve an advanced product range,
3. Process development to realise innovative production processes.”

About this Featured Story

This Featured Story appeared in Stainless Steel World April 2024 magazine. To read many more articles like these on an (almost) monthly basis, subscribe to our magazine (available in print and digital format) – SUBSCRIPTIONS TO OUR DIGITAL VERSION ARE NOW FREE.

Every week we share a new Featured Story with our Stainless Steel community. Join us and let’s share your Featured Story on Stainless Steel World online and in print.