Centrifugally cast steel pipes
Centrifugally cast steel pipes are manufactured by pouring refined melted-steel is poured into the metal mold horizontally rotating at high speed, and melted steel is spread uniformly over the whole wall of the metal mold and solidify while maintaining its hollow shape in genuine circle.
Centrifugally casting process
Materials according to the application are melted in a high-frequency induction furnace and fabricated in any size.
Manufacturing process
Melting
The steel is melted in a high-frequency induction furnace.The chemical composition is analyzed and the composition is adjusted before the melted steel pay out.
Casting
Melted-steel is poured into the rotating mold. The thickness of the product is adjusted by adjusting the weight of the melted-steel.
Drawing
Pull out the product that has solidified in the mold.
Heat treatment
Normalizing, annealing, quenching, and tempering is performed to ensure mechanical properties.
Shot blasting
Shot blasting for the outer surface of the material and grinder treatment of the inner surface are performed, and then the material is cut into product length.
Mechanical test
Test the product to see if it meets the specified values, and prepare and submit a mill sheet along with the results of chemical composition analysis.
Machining
Machining such as turning, milling, and polishing.
High precision machining is possible with our own machine tools.
Welding
Flange welding, butt welding of long products, etc., can be performed according to the application.
High quality welding by submerged arc welding machine is also available.
Non-destructive Inspection
Non-destructive testing and dimensional inspection of VT/PT/UT/MT, etc. are performed and submitted as inspection records.
Shipping
Shipment of qualified products in packing style as per specifications.
We can also handle overseas packaging.
Video Introduction (Japanese)
Features and characteristics
High roundness and dense material Very few casting defects (porosity and slag inclusion) The material is uniform, and the strength loss in the wall thickness direction is suppressed compared to other manufacturing methods.The wall thickness can be set freely. (The outer diameter of the product can be set for each mold used, and the inner diameter can be set according to the weight of molten steel.)
Comparison with materials made by other processes
Comparison of macro structures (in the condition etched by undiluted hydrochloric acid solution).
Positions where test pieces were picked from
Longitudal direction (90°from rolling direction)
Transverse direction (rolling direction)
Wall thickness direction
Advantages of SNK’s centrifugally cast steel pipes
Materials and casting technology
We will cast and propose materials according to the application.
Capable of handling a wide variety of materials (cast steel, cast iron, stainless steel, etc.), including SNK’s proprietary ultra-high strength steel and wear-resistant steel.
Substantial cost reduction can be achieved by changing from solid to thick-walled materials.
Capable of casting large diameter (max.1163mm) and thick wall (max.200mm) materials.
Cost reduction through yield improvement is possible.
Casting of short products is possible by applying an inner cover (cut ring) to the mold.
It is possible to combine different properties in the inner and outer layers.
Capable of producing dual-layered pipes by combining materials with dierent inner and outer layers.
Welding and machining technology
Welding and processing of special steel, special shapes, long connections, etc. are possible.
Know-how cultivated through machine tool manufacturing enables high-precision, high-grade welding and machining.
Production technology
We have multiple melting furnaces and can handle a wide variety of products.
Made to order, casting is possible from one piece
Short delivery time, visualization of delivery time, and reduction of the burden on the person in charge of arrangements are possible.
We are capable of handling the entire process from material melting to casting, heat treatment, welding, finishing, surface treatment, and assembly.
Products
For material
Spool for winding sheet for rolling
- In addition to the high strength in the direction of wall thickness due to centrifugal casting, SNK’s original ultra-high tensile steel is used, which is resistant to deformation and has a long service life.
- Special slit shapes and deformation correction processing for other manufacturers’ products are also available.
- High precision machining with machines that utilize the know-how of a machine tool manufacturer.
- We will propose materials and standards according to the customer’s usage conditions.
For the industrial machinery industry
Cylinder tubes and cylinder rods for large hydraulic cylinders (for presses, sluices, ships, etc.)
- Customization is possible to adjust the inner and outer diameter and wall thickness to just the right size.
- Maximum actual size is 940mm in outer diameter
- Welding of parts such as flanges, welding to long objects, honing of inner diameters, and tapping of screws can be manufactured up to the finished product.
For construction and civil engineering industries
Centrifugally cast steel pipes for building structures (SN columns)
- The SN column (circular column) can be easily manufactured with a small diameter and thick wall due to the characteristics of its manufacturing method. It has high resistance to axial compression and torsional rigidity, and retains very high durability.
- For the Tokyo Sky Tree®, all steel pipes with the same outer diameter are used to ensure design integrity. The load-bearing part of the first observatory requires a material with higher strength than other parts, and only SNK’s centrifugal casting pipes have been able to achieve a tensile strength of 60kg/mm class in a size of 318.5 x 32T x 4m
Steel pipe columns for subway stations
- Not only casting the seamless steel pipes with high earthquake resistance, but also welding and assembly of upper and lower pressure plates.
- Quality control certified as steel pipe columns.
- High specification realization capability based on the track record of more than 100 stations
Products that can be produced
Available sizes
| Outer diameter： | Φ100～1,163mm |
|---|---|
| Wall thickness： | 10～200mm |
| Length： | ～5,500mm ※Lengthening by welding is possible. |
| Single weight： | ～7ｔ |
Available materials
- Centrifugally cast steel pipes material standard (JIS standard)
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JIS G5101 Carbon steel castings JIS G5102,5201 Centrifugally cast steel pipes for welded structures JIS G5111 High strength carbon steel and low alloy steel cast and forged for structural purposes JIS G5121 Stainless steel castings JIS G5122 Heat resistnt steel casts JIS G5501 Grey cast iron JIS G5502 Ductile cast iron JIS G5152 Cast steel products for low temperature and high pressure service JIS G5202 Centrifugally cast steel pipes for high temperature and high pressure service
- Centrifugally cast steel pipes material standard (SNK original)
- For abrasion resistant pupose
For super high tensile strength steel
Centrifugally cast steel pipes for building structures (SN columns) 【approved by the competent minister】