帝国製鋲 List of Products and Services

Teikoku Seibou Co., Ltd. has both hot and cold forging equipment, utilizing the characteristics of each to manufacture standard bolts, as well as irregular bolts and special steel bolts, regardless of the lot size, and is supported by many companies as a fastener manufacturer. Furthermore, we are equipped with processing facilities that can carry out secondary processing of bolts consistently. We respond to various fastener needs. We are offering a DVD that introduces our forging technology for free. The DVD provides an overview of hot and cold forging technology. *Companies wishing to receive the "DVD" should contact us and indicate "DVD request." *For urgent matters or technical inquiries, please contact us directly through our website.

• others

Introducing the "High-Strength Hex Bolt" from Teikoku Seibou, a manufacturer of fastening components related to large machinery and railways. For strength grades "8.8" and "10.9," we use mechanical structural alloy steel (SCM435) and low-carbon boron steel as materials. We offer a lineup of 9 sizes: M16, M20, M22, M24, M27, M30, M33, M36, and M39. 【Features】 ■ High strength is achieved through heat treatment, ensuring stable quality. ■ When combined with nuts, stable torque management is possible during tightening. *For more details, please refer to the materials. Feel free to contact us with any inquiries.

• Joints between components
• Work tools

At Teikoku Seibou Co., Ltd., we have been dedicated to each product with reliable technology and a trustworthy system. To further respond to the "next needs," we have developed a system that leverages the characteristics of both hot and cold forging technologies cultivated up to today, allowing us to accommodate orders for standard bolts as well as custom shapes and irregular bolts, regardless of the lot size. The "21st Century Product Catalog" includes not only "company history," "JIS approved items," "production steel materials," and "main production and inspection equipment," but also a wide range of products such as "10.9 high-strength bolts," "10.9 hex socket bolts," "dog nails and stop nails," "rail screws," "rail fastening bolts," "gauge adjustment fittings," and "joint plate bolts." *For urgent or emergency inquiries, or for technical questions, please contact us directly through our website.

• Steel
• Secondary steel products
• Work tools

At Teikoku Seibou Co., Ltd., we are dedicated to developing automated equipment for self-tapping screws and continuously striving to improve our technology, producing better products at lower costs, and receiving patronage from various sectors and fields. We have been manufacturing bolts, screws, and nails, which are essential for social infrastructure such as railways, construction, civil engineering, and shipbuilding, for nearly a century. With the motto "We want to meet the next needs," our entire company is united in contributing to society and advancing into the future as "Teikoku Seibou, an old yet new company." In our "Business Introduction," we sincerely respond to user needs with "technical capabilities" backed by solid technology and a robust system, high productivity utilizing years of knowledge and experience in "production systems," and "quality control" that provides peace of mind through rigorous inspections. Additionally, in the "Product Lineup Introduction," we feature a wide range of products including "dog nails," "gauge blocks," "long head studs," "SS bolts," "epoxy powder coating," "10.9 and 8.8 high-strength bolts," and "stainless steel hex socket bolts," among many others. *For urgent or emergency matters, or technical inquiries, please contact us directly through our website.

• Joints between components
• Work tools
• Road construction

At Teikoku Seibou, a leading company in rail fastening component manufacturing, we handle "dog spikes" used for fastening rails to wooden and synthetic sleepers. The commonly used standard dog spike "Dog Spike (Standard) JISE-1108" was established as a JIS in 1990 and is available for general use and N rails. In addition, we offer "Dog Spike (Round Head Spike)" for use with N rail switches (using wit screws), floor plates for expansion joints, and switch-type plates for fastening sleepers, as well as "Dog Spike (Square Head Spike)" for use with N rail switches (using metric screws) and floor plates for expansion joints and switch-type plates for fastening sleepers. 【Features】 <Dog Spike (Standard)> ■ The commonly used standard dog spike ■ Established as JIS in 1990 (JIS-E1108) ■ Available for general use and N rails *For more details, please refer to the PDF document or feel free to contact us.

• Railway Construction
• others

At Teikoku Seibou, a leading company in rail fastening component manufacturing, we handle "rail screws." The intended uses are for fixing rails and fastening tie plates. We have cut threads to increase the pull-out resistance of the screws. With the spread of synthetic sleepers, there are often cases where screws with thinner shaft diameters or smaller head diameters are produced, and the shapes are changed depending on the usage location, compared to conventional rail screws. Once we receive your drawings, we will start with mold design and proceed to manufacturing, so please feel free to consult with us. 【Features】 ■ High-precision and strong threaded parts due to hot rolling method ■ Threads are cut to increase the pull-out resistance of the screws ■ JIS mark certification product (JIS E1109) *For more details, please refer to the PDF materials or feel free to contact us.

• Safety and consumables

The 'Dog Nail / Trapezoidal Screw' is shaped remarkably like a dog's head and can be widely used for various purposes. Please get creative with its use as an exterior decoration for buildings or as a hook for hanging items. If you would like to order it as a commemorative item, we can also include text or dates. 【Features】 ■ Can be used as an exterior decoration for buildings or as a hook for hanging items ■ Text and date engraving is also possible *For more details, please refer to the PDF document or feel free to contact us.

• Synthetic Resin Plywood
• Flag hardware and decorative hardware
• Road construction

At Teikoku Seibou, which has been manufacturing bolts, screws, and nails essential for social infrastructure such as railways, construction, civil engineering, shipbuilding, and aircraft for about 100 years, we handle "joint plate bolts and nuts" used in railway applications. Our company manufactures ordinary steel joint plate bolts and heat-treated joint plate bolts based on JIS E1107, Appendix 1 (regulations) for Whitworth thread joint plate bolts and nuts. 【Types and Uses of Bolts】 ■ Type A - For 30kg (A30) rails: Ordinary joint plates - For 37kg (A37) rails: Ordinary joint plates - For 50kg (A50) rails: Ordinary joint plates ■ Type B - For 30kg (B30) rails: Heat-treated joint plates - For 37kg (B37) rails: Heat-treated joint plates - For 40kgN (B40N) rails: Ordinary joint plates / Heat-treated joint plates - For 50kg (B50) rails: Heat-treated joint plates - For 50kgN (B50N) rails: Ordinary joint plates / Heat-treated joint plates *For more details, please refer to the PDF document or feel free to contact us.

• Safety and consumables

The bolts for railway switches (points) are manufactured using a hot forging system. A variety of chock bolts and various shaped bolts related to signals and electrical systems are produced using this hot forging system. We manufacture different types of screws, including metric screws and Whitworth screws (inch-based), according to your requests. Based on our outstanding technical capabilities, we also produce a variety of other items. *For urgent or emergency inquiries, or technical questions, please contact us directly through our website.

• Safety and consumables

♦P.C. Tie Rod Trapezoidal Screw Bolt♦ The "trapezoidal screw/bolt" for concrete ties is manufactured using the "hot-rolled rolling method," which offers superior strength compared to machining. It has already been successfully used in numerous cases for the Shinkansen and can also be used for securing parts such as the hanging sections of concrete walls in civil engineering and underground areas. ★Please feel free to consult us regarding other applications or prototypes. We also design "male threads." 【Features of the Hot-Rolled Rolling Method】 - Maintains the fiber structure of the steel, providing excellent strength - High precision with no eccentricity - Suitable for mass production - Custom products for special shapes/trapezoidal screws are also available ♦Connection Plate Bolt and Nut♦ Standard steel connection plate bolts and heat-treated connection plate bolts. 【Features】 - Heat-treated connection plate bolts are produced in three grades: 5.6, 8.8, and 10.9 - Obtained JIS display permission (certification) ◆Prototype Forged Parts◆ If you provide us with drawings, we can design and prototype molds regardless of quantity! This allows for pre-processing by forging, not only for bolts but also for complex shapes or when you want to reduce excess material in lathe machining. *For more details, please contact us or refer to the catalog.*

• Concrete wall

Electrolytic corrosion is a phenomenon where metal rapidly dissolves due to the flow of electricity from natural phenomena on the surface of the metal. Iron structures are painted, and this paint contains a lot of zinc, which provides rust prevention effects. However, there are many areas of corrosion on bolts that have been treated with hot-dip galvanized coating, especially in places that experience repeated wetting and drying or have high humidity. To help address these issues, we also sell bolts that have been coated with nylon-based and epoxy-based treatments. *For urgent or emergency cases, or for technical inquiries, please contact us directly through our website.*

• Natural paints (water-based, ink, etc.)
• Safety and consumables

High-strength hex bolts (M12 to M30), which are active in construction work such as steel frames and bridges, are one of our main products. High-strength hex bolts play an important role in supporting the construction industry of tomorrow as components for construction machinery. They are made from special steel materials such as low-carbon manganese, chromium, and boron steel, ensuring stable mechanical properties. We maintain stable quality through consistent production using advanced bolt forming equipment (for diameters of 27mm or less). Leveraging years of experience in hot forging technology, we also manufacture large-diameter high-strength hex bolts (M33 to M76). We mass-produce products with stable quality through strict lot management based on JIS B1186. We have a rich inventory of standard products and respond quickly to orders. *For urgent or emergency inquiries, or technical questions, please contact us directly through our website.

• Work tools

Stainless steel is excellent in design, corrosion resistance, and durability, and has been widely used in various fields for a long time. High-strength hex bolts used for stainless steel structural materials are regulated by JIS B1186 "Set of High-Strength Hex Bolts, Hex Nuts, and Flat Washers for Friction Joints." However, since the chemical composition of the material and the manufacturing method are not specified here, high-strength hex bolts made of stainless steel are manufactured based on the standards of the Stainless Steel Structural Engineering Association, SSBS301 "Set of High-Strength Hex Bolts, Hex Nuts, and Flat Washers for Structural Stainless Steel" (10T-SUS, 10-SUS, 35-SUS). *For urgent or emergency cases, or for technical inquiries, please contact us directly through our website.

• Safety and consumables
• Structural Materials

The high-strength hex bolts with hot-dip galvanized coating from Teikoku Seibou Co., Ltd. have undergone examination based on the Building Standards Act regarding corrosion resistance, mechanical properties, tightening functionality, delayed fracture characteristics, and construction performance, and have obtained general certification from the Minister of Land, Infrastructure, Transport and Tourism. The coating weight of the bolts, nuts, and washers is 550g/m² or more. Furthermore, the coating weight of the components is managed under the same standards, ensuring maintenance-free corrosion resistance over the long term. In the zinc plating process, acid washing is avoided as much as possible to prevent hydrogen intrusion, eliminating concerns about delayed fracture. The nuts are treated with a special lubrication process, guaranteeing stable axial force during tightening construction using the nut rotation angle method. *For urgent or emergency cases, or for technical inquiries, please contact us directly through our website.*

• Safety and consumables
• Rock drills, demolition machines, and excavators

TM truss bolts are used in the spherical joint sections of the TM spatial truss (by Taiyo Kogyo Co., Ltd.), which creates an ideal space without columns. TM bolts are made from chromium-molybdenum steel (SCM435) and nickel-chromium-molybdenum steel (SNCM439), and are heat-treated to achieve high strength using advanced heat treatment equipment. Additionally, they are specially treated for corrosion resistance to prevent delayed fracture. Teikoku Seibou Co., Ltd. can provide high-quality, high-strength, and corrosion-resistant treatment for bolts of various sizes (with a maximum neck length of 1,000 mm). *For urgent or emergency inquiries, or for technical questions, please contact us directly through our website.

• Safety and consumables

The production of drift pins requires advanced heat treatment technology. If heat treatment management is insufficient, issues such as chipping or bending of the pins may occur. At Teikoku Seibyo Co., Ltd., we manufacture drift pins with excellent heat treatment technology and strict material selection, earning immense trust from our customers. *For urgent or emergency cases, or for technical inquiries, please contact us directly through our website.*

• Steel
• Secondary steel products
• Safety and consumables

There are two types of hexagon head bolts based on the width of the two flat sides: 1. Standard hexagon bolts (regular hexagon bolts), and 2. Small hexagon bolts (hexagon bolts with a head width smaller than that of standard ones). The applicable strength classifications are 4.6, 8.8, and 10.9. Teikoku Seiko Co., Ltd. can manufacture bolts of all sizes according to user needs. Additionally, since October 1993, Teikoku Seiko Co., Ltd. has been producing high-strength hexagon bolts with a diameter of 10.9 (JIS standard) using advanced heat treatment technology that leverages hot forging technology (with a maximum shank length of up to 1,000 mm). *For urgent or emergency inquiries, or technical questions, please contact us directly through our website.

• Safety and consumables
• Joining and fastening materials

Hexagon socket head bolts are generally used without nuts, so the term "screw" is more accurate. However, since the name "hexagon socket bolt" has become widespread, they are also referred to as cap bolts. The applicable strength grades are 8.8, 10.9, and 12.9. They are tightened with a hexagon rod wrench (with a maximum neck length of 1,000 mm). This contributes to the compactness of the equipment, improves the design performance of the devices, allows for application in narrow spaces, and enhances workability. With high tightening force, it improves reliability by preventing loosening. *For urgent or emergency inquiries, or technical questions, please contact us directly through our website.

• Safety and consumables

The stainless steel bolts manufactured by Teikoku Seibou Co., Ltd. are produced based on years of accumulated technology and proven results. All products are made to order. The manufacturing process includes hot forging, solution treatment, NC cutting, thread rolling, and surface treatment, all carried out under strict quality control and with extensive experience in each stage. The range of thread rolling capabilities spans from small diameters to large diameters, meeting all kinds of needs (with a maximum neck length of up to 1,000mm). *For urgent or emergency inquiries, or for technical questions, please contact us directly through our website.

• Safety and consumables

Teikoku Seibou Co., Ltd. has been dedicated to each task with reliable technology and a trustworthy system. Furthermore, in order to respond to the "next needs," we have established a system that leverages the characteristics of the hot and cold forging technologies we have cultivated up to today, allowing us to accommodate all kinds of orders. Whether it's standard bolts or irregular products and bolts, please feel free to reach out to us with any inquiries or requests for quotes, regardless of the quantity, including questions like "Can you make something like this?" or "Can it be produced more economically?" *For urgent cases or technical inquiries, please contact us directly through our website.

• Safety and consumables

The "Large Machine Hex Bolt" from Teikoku Seibou is a hex bolt made from chromium-molybdenum steel (SCM435, 440) and nickel-chromium-molybdenum steel (SNCM439). 【Features】 ◆ High strength due to quenching with advanced heat treatment equipment, ensuring stable quality ◆ Stable torque management during tightening is possible when combined with nuts ◆ The hex head bolts are available in two types based on the width of the two opposing sides: - Standard hex bolt (regular hex bolt) - Small hex bolt (hex bolt with a head width smaller than that of the standard hex bolt) - Applicable strength classifications are 4.6, 8.8, 10.9 *For urgent or emergency inquiries, or technical questions, please contact us through our website.

• Joining and fastening materials

"Powerful Hex Bolts 8.8 and 10.9" are large bolts ranging from M30 to M60, finished through hot forging. Despite their large size, they achieve high strength classified as 8.8 or 10.9 according to JIS standards. Customization is possible for special dimensions in length and thickness, as well as for changes in head shape to special forms. ◎ Prototyping is also possible upon request. 【Features】 ■ Customization for special dimensions and shapes is available ■ Used in machine tools, wind power generation, and various construction materials ■ Made of alloy steel and low-carbon boron steel *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools

The "stainless steel high-strength hex bolt" is a material that excels in design, corrosion resistance, and durability, and has been widely used in various fields for a long time. Customization to special shapes with unique dimensions for length and thickness, as well as changes to the head shape, is possible. ◎ Various stainless steel bolts can also be manufactured according to your requests. 【Features】 ■ Manufactured under strict quality control with extensive experience in all processes ■ Customization to special dimensions and shapes is possible ■ The range for rolling is wide, from small diameters to large diameters (with a maximum under-head length of 1,000mm possible) *For urgent or emergency inquiries, or for technical questions, please contact us directly through our website.

• Safety and consumables
• Structural Materials

The production of dog spikes has walked alongside Japan's long railway history. Even today, they are highly regarded both domestically and internationally for use in fastening rails for wooden and synthetic sleepers. "Dog spike (standard)" is defined by JIS and comes in general and N-rail types. The N-rail type "dog spike (round head)" is used for fastening sleepers in turnouts, expansion joints, and turnout-type plates, while the "dog spike (square head)" is also available for fastening sleepers in turnouts and expansion joints. 【Features】 ○ General use - The angle under the head is 13° ○ N-rail use - The angle under the head is 1:10 ○ Square head spike - The angle under the head is 1:6 - Designed considering the shortcomings of the round head spikes listed below *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools
• Road construction

The "rail screw nail" is a screw that has been threaded to increase the resistance to pulling out nails. Its intended use is the same as that of dog nails, for fixing rails and tie plates. With the widespread use of synthetic sleepers, there are many cases where screws with thinner shaft diameters or smaller head diameters are produced, and the shape is changed depending on the application. Once we receive the drawings, our company will start with the design of the molds and proceed with manufacturing. 【Features】 ○ Provides a higher fastening strength to wood and synthetic sleepers, making it less likely to loosen ○ Features a high-precision and strong screw section due to the hot rolling method *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools

"Joint plate bolts and nuts" refer to ordinary steel joint plate bolts and heat-treated joint plate bolts. Our company manufactures them based on JIS E1107 for Whit threads in joint plate bolts and nuts. JIS E1107, E1113, and E1114 have been integrated and announced as the new JIS E1107. 【Features】 ○ Heat-treated joint plate bolts are produced in three types: 5.6, 8.8, and 10.9 ○ Obtained JIS display permission (certification) *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools
• Road construction

The "PC sleeper trapezoidal screw bolt" is a bolt that fastens the rail to a sleeper embedded with a synthetic resin plug that serves as a female thread, using a spring. Our company manufactures the threaded part of the bolt using a hot-rolled rolling method. As a result, unlike cutting methods, the fiber structure of the steel material is maintained without being severed. It has been adopted in many newly constructed Shinkansen lines, including the Sanyo Shinkansen. 【Features of the Hot-Rolled Rolling Method】 - Superior strength due to the intact fiber structure - High precision with no eccentricity - Suitable for mass production - Custom products for various shapes and trapezoidal threads are available - Machining of special steel and stainless steel threads is also possible *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Steel
• Secondary steel products
• Work tools

"Hex bolts (4.6 to 12.9)" are bolts used in large machinery, civil engineering, and maritime applications. Hex head bolts come in two types based on the width across the flats: standard hex bolts and small hex bolts. Our company can manufacture bolts of all sizes according to user needs (with a maximum shank length of 1,000mm). 【Features】 ○ Hex bolts (8.8, 10.9) are made from chromium-molybdenum steel (SCM435, 440) and nickel-chromium-molybdenum steel (SNCM439). ○ The use of advanced heat treatment equipment ensures high strength and stable quality. ○ When combined with nuts, stable torque management during tightening is possible. ○ Applicable strength grades: 4.6, 6.8, 8.8, 10.9, 12.9. *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools
• Joining and fastening materials

The "hex bolt (6.8)" is a bolt used in large machinery, civil engineering, and shipbuilding. Hex head bolts come in two types based on the width across the flats: standard hex bolts and small hex bolts. In addition to hex bolts (6.8), we also offer hex bolts (4.6, 8.8, 10.9, 12.9). Our company can manufacture bolts in various sizes according to user needs (with a maximum shank length of 1,000mm). 【Features】 ○ The quality is stable due to high-strength tempering with advanced heat treatment equipment. ○ Stable torque management during tightening is possible when combined with nuts. *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools

"Hex bolts (8.8, 10.9)" are bolts used in large machinery, civil engineering, and shipbuilding. Hex head bolts come in two types: standard hex bolts and small hex bolts, depending on the width across the flats. Our company can manufacture bolts of all sizes according to user needs (with a maximum shank length of 1,000mm). 【Features】 ○ Hex bolts (8.8, 10.9) are made from chromium-molybdenum steel (SCM435, 440) and nickel-chromium-molybdenum steel (SNCM439). ○ The use of advanced heat treatment equipment ensures high strength and stable quality. ○ When combined with nuts, stable torque management during tightening is possible. *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools
• Joining and fastening materials

The "Hexagon Socket Bolt JISB1176" is a bolt used in large machinery, civil engineering, and shipbuilding. Hexagon socket head bolts are generally used without nuts. The applicable strength grades are 8.8, 10.9, and 12.9. They are tightened with a hexagon rod wrench (with a maximum shank length of 1,000mm). Our company has established a system to accommodate all orders by leveraging the characteristics of hot and cold forging technology. 【Features】 ○ Compact design of equipment ○ Improved design performance of devices ○ Application in narrow spaces and enhanced workability ○ Increased reliability by preventing loosening with high tightening force *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components
• Work tools

"Hot-dip galvanized high-strength bolts" are bolts used for construction machinery. High-strength hex bolts (M12 to M30), which are active in steel frame and bridge construction, are also one of our main products. We use special steel materials for high-strength hex bolts, such as low-carbon manganese, chromium, and boron steel, ensuring stable mechanical properties of the products. We have a rich inventory of standard products and will respond quickly to your orders. 【Features】 - Utilizing advanced equipment for bolt forming (φ27mm and below) for consistent production, ensuring stable quality. - Leveraging years of hot forging technology, we also manufacture large-diameter high-strength hex bolts (M33 to M76). - Mass production of products with stable quality through strict lot management (based on JIS B1186). *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Work tools

Titanium can be broadly classified into "pure titanium" (there are four types according to JIS) and "titanium alloys." "Pure titanium" means commercially high purity and is also referred to as CP titanium, which stands for Commercially Pure Titanium. Titanium alloys are divided into those primarily aimed at improving "corrosion resistance" and those aimed at enhancing "mechanical strength" and "workability." 【Features】 ○ Lightweight and strong titanium alloys ○ Excellent corrosion resistance ○ Excellent heat resistance *In case of urgent or emergency situations, please direct technical inquiries through our website.

• others

Stainless steel bolts are manufactured based on years of our accumulated technology and achievements. Additionally, there are processes such as hot forging, solution treatment, NC cutting, thread rolling, and surface treatment, all of which are carried out under strict quality control and with extensive experience. The range of rollable diameters is wide, from small to large, meeting all kinds of needs. *In case of urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components

In addition to standard bolts, we have established a system to respond to various orders by leveraging the characteristics of our hot and cold forging technologies that we have cultivated up to today, in order to meet the "next needs" for special items, irregular shapes, and forged products. For forged parts and irregular items, regardless of the quantity, please feel free to reach out with inquiries such as "Can you make something like this?" or "Is there a more economical way to produce this?" for consultations and estimates. *For urgent or emergency cases, please contact us with technical questions through our website.

• others

We would like to introduce our "Hex Bolts," which are heat-treated to high strength and possess stable quality. Hex head bolts come in two types based on the width across the flats. The applicable strength classifications are 4.6, 8.8, and 10.9. At Teikoku Seibyo, we can manufacture bolts in various sizes according to user needs. Additionally, since October 1993, our company has been producing high-strength hex bolts with a diameter of 10.9 (JIS standard) using advanced heat treatment technology that leverages hot forging techniques (with a maximum shank length of 1,000 mm). 【Features】 ■ Hex bolts (8.8, 10.9) are made from chromium-molybdenum steel (SCM435, 440) and nickel-chromium-molybdenum steel (SNCM439). ■ They are heat-treated to high strength using state-of-the-art heat treatment equipment, ensuring stable quality (8.8, 10.9). ■ When combined with nuts, they allow for stable torque management during tightening. ■ JIS mark certification (JIS B1180). *For more details, please refer to the PDF document or feel free to contact us.

• Joining and fastening materials

Hex socket bolts (caps) are generally used without being paired with nuts, so referring to them as screws is more accurate. However, since the name hex socket bolt has become widespread, they are also called cap bolts. The applicable strength grades are 10.9 and 12.9. They are tightened with a hexagonal rod wrench (with a maximum neck length of 1,000 mm). *For urgent or emergency situations, or for technical inquiries, please contact us directly through our website.

• Joints between components

Stainless steel is excellent in design, corrosion resistance, and durability, and has been widely used in various fields for a long time. At Teikoku Seibou, we manufacture "stainless bolts" based on years of accumulated technology and achievements. The range of rollable diameters is broad, from small to large sizes, catering to various needs (with a maximum neck length of 1,000mm possible). All products are made to order. 【Features】 ■ All products are made to order ■ Manufactured under strict quality control and extensive experience in all processes, including hot forging, solution treatment, NC cutting, thread rolling, and surface treatment ■ The range of rollable diameters is broad, from small to large sizes (with a maximum neck length of 1,000mm possible) *For more details, please refer to the PDF document or feel free to contact us.

• Joining and fastening materials

At Teikoku Seibou, a leading company in rail fastening component manufacturing, we handle "dog spikes and rail screws." "Dog spikes" are used for fastening rails to wooden and synthetic sleepers. In addition to the commonly used standard dog spike "Dog Spike (Standard) JIS-E1108," we offer dog spikes (round head) and dog spikes (square head) in our lineup. "Rail screws" are used for fixing rails and fastening tie plates, and we provide types A, B, and C according to their applications. 【Features of Dog Spike (Standard)】 ■ Currently widely used standard dog spike ■ Available for general use and N rails (the difference is the angle under the head of the dog spike) ■ Certified product under the JIS mark display system (JIS E1108) *For more details, please refer to the PDF materials or feel free to contact us.

• Road construction

High-strength hex bolts (M12 to M30) actively used in steel frame and bridge construction 【Features】 - Coated with a surface treatment to prevent rust in highly corrosive environments such as coastal and offshore areas. - Made from special steel materials (developed by Sumitomo Metal Industries, Ltd.) for high-strength hex bolts, including low-carbon manganese, chromium, and boron steel, ensuring stable mechanical properties of the products. - Utilizing advanced equipment for bolt forming (up to φ27mm), we conduct integrated production, ensuring stable quality. - Leveraging years of hot forging technology, we also manufacture large-diameter high-strength hex bolts (M33 to M76). We mass-produce products with stable quality through strict lot management based on JIS B1186. We maintain a large inventory of standard products and respond quickly to orders. *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Work tools

Hexagon socket bolts (caps) are generally used without being paired with nuts, so referring to them as screws is more accurate. However, since the name hexagon socket bolt has become widespread, they are also called cap bolts. The applicable strength grades are 8.8, 10.9, and 12.9. They are tightened with a hexagon rod wrench (with a maximum neck length of 1,000 mm). *In urgent or emergency cases, please direct any technical inquiries through our website.

• Joints between components

Stainless steel bolts are manufactured based on years of our accumulated technology and achievements. Additionally, there are processes such as hot forging, solution treatment, NC cutting, thread rolling, and surface treatment, all of which are carried out under strict quality control and with extensive experience. The range of rollable diameters is wide, from small to large, meeting all kinds of needs. *For urgent or emergency inquiries, please contact us through our website for technical questions.

• Joints between components

Special products, irregular products, and wit screws are equipped to respond to the "next needs" by leveraging the characteristics of the hot and cold forging technologies cultivated up to today, allowing us to accommodate all types of orders. In addition to standard bolts, we welcome inquiries and estimates for irregular products and irregular bolts, regardless of the quantity, such as "Can you make something like this?" or "Can it be produced more economically?" *For urgent or emergency cases, please contact us with technical questions through our website.

• Subsidiary materials