國友熱工 List of Products and Services

"Vacuum hardening" is a hardening method that involves creating a vacuum state inside a vacuum furnace using a vacuum pump, heating the product, and then cooling it with nitrogen gas using fan cooling or oil cooling. It is suitable for heat treatment of mold steel, high-speed tool steel, and finished products. The effective dimensions of the equipment are 600H × 600W × 900L, and the maximum processing weight is 300 kg. 【Features】 ■ Creation of a vacuum state inside the vacuum furnace using a vacuum pump ■ Cooling with nitrogen gas using fan cooling or oil cooling ■ Suitable for heat treatment of mold steel, high-speed tool steel, and finished products *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• Steel
• Special Steel

We would like to introduce the "Bright Quenching" process conducted by Kuniyu Thermal Engineering Co., Ltd. When high-temperature heat treatment is performed in an atmospheric furnace, a black scale (oxidation film) forms on the surface. However, by heating and quenching in a furnace atmosphere that does not cause oxidation or decarburization, a bright appearance is achieved. We accommodate a wide range of steel types, including JIS steel grades such as carbon steel, alloy steel, and tool steel, as well as various standards like AMS and DIN. 【Features】 ■ Heating and quenching in a non-oxidizing and non-decarburizing furnace atmosphere ■ Finishing with a bright appearance ■ Compatibility with various steel types *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• Steel
• Special Steel

"Solution treatment" is a process in which austenitic, austenitic-ferritic, and precipitation-hardening stainless steels are heated and then rapidly cooled. This process dissolves chromium and other elements that have precipitated during forging, rolling, and cold working into the alloy, facilitating the formation of a passive film and improving corrosion resistance. It is also performed as a pretreatment for the precipitation hardening of precipitation-hardening stainless steels. [Features] - Dissolves chromium and other elements that have precipitated during forging, rolling, and cold working into the alloy - Facilitates the formation of a passive film and improves corrosion resistance - Also performed as a pretreatment for the precipitation hardening of precipitation-hardening stainless steels *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• stainless

"Precipitation hardening treatment (aging hardening heat treatment)" is a process that increases hardness by precipitating dissolved solute atoms in steel, such as precipitation hardening stainless steel, as intermetallic compounds. Solution treatment is required as a pre-treatment for precipitation hardening. The effective dimensions of the equipment are 1000H × 1200W × 1800L, and the maximum processing weight is 2000 kg. [Features] - Improvement of strength in stainless steel, titanium steel, aluminum alloys, and copper alloys - Solution treatment is required as a pre-treatment for precipitation hardening *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• stainless
• aluminum

"Annealing" is a process that standardizes steel to achieve a uniform structure. It aims to eliminate the effects of prior processing, refine the crystal grains to a fine uniformity, and improve mechanical properties. The effective dimensions of the equipment are Φ1500×1300H, with a maximum processing weight of 1800kg. 【Features】 ■ Uniform refinement of the structure created by casting, forging, and rolling ■ Improved machinability ■ Enhanced mechanical properties *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• Steel
• Special Steel

"Complete annealing" is a heat treatment method that softens the metal structure and improves its plastic workability. Heat and hold at the austenitizing temperature. After that, slowly cool down to about 500°C or lower inside the furnace, and then cool in the atmosphere. The effective dimensions of the equipment are Φ1500×1300H, and the maximum processing weight is 1800kg. [Features] ■ Improved plastic workability ■ Softening ■ Heat and hold at the austenitizing temperature ■ Slow cooling inside the furnace followed by atmospheric cooling *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• Steel
• Special Steel

"Quenching and tempering" is an important heat treatment that improves the properties of tough sorbite structure. The material is heated and held above the A3 transformation point, then rapidly cooled in water or oil to form a hard martensite structure, followed by tempering at an appropriate temperature of around 530 to 680°C. The effective dimensions of the equipment are Φ1400×1200H, and the maximum processing weight is 1800kg. 【Features】 ■ Adjustment of hardness, strength, and toughness ■ Improvement of material properties ■ Heating and holding above the A3 transformation point ■ Rapid cooling in water or oil to form a hard martensite structure ■ Tempering at an appropriate temperature of around 530 to 680°C *For more details, please refer to the external link page or feel free to contact us.

• Heating device
• Steel
• Special Steel

Here is a case study solved by Kuniyu Thermal Engineering. The rolls of the rolling mills used by steel manufacturers were consumable parts due to severe damage. However, since many European products were purchased at a high cost, they were considering domestic production and requested our assistance in providing materials and heat treatment methods that could offer durability equal to or greater than existing products. Our company cut the existing products and conducted detailed investigations of the microstructure and hardness distribution. Based on the results, we predicted the mechanical properties required for the components and designed, proposed, and implemented the selection of materials and heat treatment methods that could achieve this. The purchase cost was reduced by approximately 40%, and the durability became equal to or greater than that of conventional products. [Case Study] ■ Key Solutions - Successfully extended the lifespan of consumables - Comprehensive support from materials to heat treatment methods ■ Technologies Used - Improved conventional gas carburizing quenching to utilize technology that refines crystal grains *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment
• Surface treatment contract service

Here is a case study solved by Kuniyu Thermal Engineering. For the steel materials used in seismic reinforcement hardware for large buildings, simply applying standard heat treatment was insufficient to balance the mechanical properties at a high level. Additionally, considering the carbon equivalent from the perspective of welding and construction, the available steel materials were limited, and we received a request asking if we could find a solution. Since the customer had already considered various means, our company designed a microstructure that could meet the requirements. We newly developed a heat treatment method called "DF Quench" to realize that microstructure, and after various mechanical tests, we were able to commercialize the product. [Case Study] ■ Solution Points - Improved strength of seismic reinforcement hardware for large buildings - Developed new technology that could not be solved with standard heat treatment! ■ Technology Used - Dual-phase quenching "DF Quench" *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment
• Surface treatment contract service

Here is a case study solved by Kuniyu Thermal Engineering. In order to extend the lifespan of hot forging molds, we focused on suppressing the occurrence of heat cracks due to thermal fatigue by applying various surface modification treatments, primarily nitriding. However, the damage was still severe, leading to a request for assistance. We proposed a composite surface modification treatment that diffuses multiple elements. By collaborating with the customer to advance practical applications through repeated trial and error, we evolved the surface modification to better suit the forging site of the customer. As a result, we were able to achieve a mold lifespan 3 to 5 times longer than conventional types, significantly improving productivity. [Case Study] ■ Key Solutions - Investigation of causes at the manufacturing site - Achieved a mold lifespan 3 to 5 times longer ■ Technology Used - Long lifespan technology "FCD-H" *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment
• Surface treatment contract service

We would like to introduce a case solved by Kuniyu Thermal Engineering. With the trend towards miniaturization and lightweighting of automotive parts and machinery components, the use of difficult-to-process materials such as high-tensile steel plates has increased. However, this has led to issues where press molds and tooling used for plastic processing experience extremely high surface pressure, resulting in severe wear and damage. To address this, we applied the composite surface modification technology "KHD treatment" to solve the problem. The press molds for automotive parts treated with this method have achieved three times the durability compared to conventional treatments. This technology has been applied not only to press molds but also to various tooling such as pipe mandrels, contributing to increased productivity. [Case Study] ■ Key Solutions - Increased wear resistance and adhesion under high surface pressure - Enhanced durability contributing to improved productivity ■ Technology Used - Composite surface modification technology "KHD treatment" *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment
• Surface treatment contract service

"Gas carburizing" is a treatment that involves infiltrating and diffusing carbon into the surface of steel in a high-temperature gas primarily composed of hydrocarbon gas, followed by rapid cooling to form a hardened surface layer. It is mainly performed to improve the wear resistance and fatigue strength of components. Our company offers "gas carburizing hardening" and "gas carburizing nitriding hardening," accommodating a wide range from micro parts such as precision components for machining tools to large items like shield cutters for shield tunneling and gear reducers for heavy machinery and industrial machines, including both shallow and deep carburizing of alloy steel and carbon steel. [Features] ■ Gas carburizing hardening - Improved surface hardness - Enhanced toughness in the core - Increased strength and wear resistance *For more details, please refer to the PDF materials or feel free to contact us.

• Other surface treatment equipment
• Surface treatment contract service

Introducing "Plasma Carburizing and Nitriding," developed by Kuniyu Thermal Engineering, which makes the impossible possible. This is a system technology developed during the 2008 fiscal year Saboin research for "Plasma Carburizing" and "Plasma Nitriding Treatment." It imparts wear resistance without compromising the excellent corrosion resistance of austenitic stainless steel. Currently, it is primarily implemented for surface modification of molds and machine parts that require high precision. Moving forward, we aim to improve the productivity of plasma treatment and further enhance its functionality and practical application. 【Features】 ■ Simultaneous processing of a large number of small parts ■ "Barrel-type plasma treatment" that prevents the occurrence of scratches and dents ■ Low-temperature treatment around 500 degrees, resulting in minimal distortion and dimensional changes ■ Nitriding treatment tailored to the application of materials, such as improved chipping resistance ■ Imparts wear resistance without compromising the excellent corrosion resistance of austenitic stainless steel *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment

Introducing Kunitomo Thermal Engineering's unique development technology, "FCD-H Treatment." It is resistant to thermal fatigue and reduces the occurrence of heat cracks. Since no special processes are required, it can be performed simultaneously with vacuum hardening, thereby reducing labor costs. Additionally, it achieves high durability and long lifespan for hot work tool steels. 【Features】 ■ Minimal plastic deformation ■ Strong against thermal fatigue ■ No special processes required ■ Improved wear resistance and durability *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment

We would like to introduce the benefits of Kunitomo Thermal Engineering's unique development technology, "FCD Carburizing Heat Treatment." The surface of chromium-molybdenum steel transforms into alloy tool steel, allowing for a wide range of applications from chromium-molybdenum steel to SUS and various mold steels. Our company has commercialized high-concentration carburizing quenching FCD carburizing quenching, which has excellent characteristics, with the aim of applying these properties to various mechanical components. We have received high praise from many customers. 【Features】 ■ Wide compatibility from chromium-molybdenum steel to SUS and various mold steels ■ High wear resistance and impact resistance, making it less prone to chipping ■ Higher heat resistance compared to gas carburizing ■ Surface hardness of treated products can be set as desired *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment

We would like to introduce KHD processing, a unique development technology by Kuniyu Thermal Engineering. From the perspectives of weight reduction for improved fuel efficiency and enhanced safety, the introduction of high-strength steel materials is increasing. However, these materials are difficult to process, leading to significant wear on molds and tools, which necessitates improvements in strength and durability. Our development technology applies vacuum carburizing treatment to these tools, achieving excellent surface modification treatment for high surface pressure wear resistance, thereby extending the "lifespan" of molds and tools. This results in cost reduction through decreased frequency of mold replacements and improved productivity, while also addressing the anticipated "further adaptation to higher strength steel materials" in the future. [Key Points] ■ Hard coating with high resistance to high surface pressure → Generates a hard coating on the surface of the component with a hardness of approximately Hv3,000 (Hv = Vickers hardness) - Result: Wear resistance to high surface pressure is enhanced by more than twice ■ High adhesion "non-peeling coating" → Creates a "substrate gradient reinforcement layer" with a gradient hardness distribution into the base material - Result: Achieves three times the adhesion of conventional coatings with a "non-peeling coating" *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment

The "Hydrogen Suppression Carburizing Quenching Technology" achieves "high functionality + long life," contributing to the miniaturization and high strength of components. 【Features】 ■ Simultaneously improves the conflicting properties of "high strength and high toughness" - Eliminates the causes of fracture, destruction, and wear, leading to increased longevity. ■ Achieves a 33% increase in fatigue strength - Allows the use of conventional materials, enabling miniaturization and high strength. - Contributes to total cost reduction. ■ Improves the elongation of the hardened layer - Successfully maximizes mechanical properties. *For more details, please refer to the PDF document or feel free to contact us.

• Other surface treatment equipment

Vacuum carburizing hardening is a surface hardening treatment that involves heating the workpiece under reduced pressure, allowing the necessary amount of carbon to diffuse and penetrate for the formation of the specified hardened layer, and then hardening it in cooling oil. It eliminates grain boundary oxidation and incomplete hardening structures, making it possible to improve mechanical strength. 【Features】 ■ Capable of forming a deep hardened layer in a relatively short time ■ Environmentally friendly ■ Easy to operate with simple controls *For more details, please download the PDF or feel free to contact us.

• Processing Contract
• Other machine elements