|
| ขั้นต่ำ: | 1 ตัน |
| ราคา: | 800-1000 USD/Tom |
| การบรรจุแบบมาตรฐาน: | ในชุดรวมหรือในกล่องไม้ |
| ระยะเวลาการจัดส่ง: | 20-30 วันสำหรับผลิตภัณฑ์ |
| ความสามารถในการจัดหา: | 60000 ตัน/ตันต่อปี |
High-tensile structural steel tubes designated under JIS G 3474 (“High strength steel tubes for steel tower”), grade STKT590. These tubes are manufactured primarily for use in transmission towers or other steel tower structures, offering elevated strength compared with standard structural steel tubes.
Standard: JIS G 3474
Grade: STKT590
Tube type: typically longitudinally welded tubes (electric-resistance welded or automatic arc welded) for steel towers
Applicable outside diameter range (typical): 139.8 mm to 1,117.6 mm in standard JIS specification.
Thickness: as per user agreement; for instance standard clause may allow up to ~25 mm thickness for the grade in table for “25 mm or less” in some editions.
High tensile strength: minimum tensile strength of 590 MPa and up to ~740 MPa.
Good yield strength: minimum proof/yield strength of 440 MPa.
Controlled chemical composition enabling reliable welding performance and structural stability (see next section).
Carbon equivalent limit (Cₑq ≤ 0.40 %) per JIS standard, promoting weldability.
Designed for tower structural usage — makes it ideal for lattice towers, transmission towers, guyed masts, etc.
As a factory-specialist producer of STKT590 tubes, we address key customer concerns from a manufacturing perspective:
Straightness and dimensional precision: Through continuous welded tube production with calibrated rolling, we ensure tube straightness within tight tolerances and flat end faces perpendicular to the axis, meeting the JIS requirement that “the tube shall be practically straight and both ends shall be square to the axis”.
Strict thickness and diameter tolerances: We adhere to the dimensional tolerances in the JIS standard (for outer diameter and wall thickness) and maintain internal production records—this reduces misalignment and improves fit-up on tower site. For example, for thickness ≥12 mm the tolerance is +15 % / −1.5 mm (for certain sizes) under JIS G 3474.
Reliable mechanical properties: Our internal QA ensures the minimum tensile strength (590–740 MPa) and minimum yield strength (≥440 MPa) are consistently met or exceeded, verified by coupon testing. This ensures that the tube can carry high loads as required in tower structures.
Controlled chemical composition and weldability: By limiting C ≤0.12 %, Si ≤0.40 %, Mn ≤2.00 %, P ≤0.030 %, S ≤0.030 %, Nb+V ≤0.15%, and B ≤0.0002 % in line with JIS G 3474 table 2, we ensure low inclusion levels, stable microstructure, and better weldability.
Tailored for tower fabrication: We cooperate with tower manufacturers to supply cut lengths, chamfered ends, weld bevels, or combinations of diameters and thicknesses per site drawings, facilitating efficient erection on site.
| Grade | C (max %) | Si (max %) | Mn (max %) | P (max %) | S (max %) | Nb+V (max %) |
|---|---|---|---|---|---|---|
| STKT590 | 0.12 | 0.40 | 2.00 | 0.030 | 0.030 | 0.15 |
| STKT540 | 0.23 | – | 1.50 | 0.040 | 0.040 | – |
| STKT520 (*) | – | – | – | – | – | – |
| STKR590 (rectangular tube grade) | – | – | – | – | – | – |
| API X70 (pipe grade for reference) | ~0.22 | ~0.30 | ~1.50 | ~0.025 | ~0.015 | – |
* Note: STKT520 is included for illustrative purposes though detailed composition may not be publicly documented in the same way.
Here is a table showing mechanical property minima for STKT590 plus comparable grades.
| Grade | Tensile Strength (Rm MPa) | Yield/Proof Strength (σs MPa) | Elongation (δ %) |
|---|---|---|---|
| STKT590 | 590-740 | ≥440 | ≥20 (for D>40 mm) |
| STKT540 | ~540 (approx) | ≥? | ≥? |
| STKT520 | (approx ~520) | – | – |
| A572 Grade 50 (ASTM) | 345-550 | ≈345 | 21 min |
| S355J2H (EN) | 470-630 | ≈355 | 22 min |
JIS G 3474: High strength steel tubes for steel tower (Japan)
Execution manufacturing methods per standard: manufacture by electric-resistance welding or automatic arc welding (straight seam) using fine-grain killed steel; no heat treatment typically required.
Chemical analysis by JIS G 0320, product analysis by JIS G 0321.
These tubes are used in tower structural applications, especially in transmission towers, power line towers, communications towers, wind-turbine tower components, or other lattice-structure towers requiring high strength and welded tubular members.
Fabrication of lattice tower legs (diagonal and vertical members) using STKT590 tubes to reduce weight and improve structural capacity compared to conventional tubes.
Horizontal members/bracing tubes in transmission towers where high tensile strength allows smaller section sizes and better economy.
Pre-fabricated welded sections for guyed masts or telecom towers where the tube must meet strict dimensional and straightness requirements.
In wind-tower applications (lower sections) where high strength tubes enable thinner walls and larger diameter for improved stiffness and structural efficiency.
A: manufacturer,also can do trading.
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock, it is according to quantity.
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.
|
|
| ขั้นต่ำ: | 1 ตัน |
| ราคา: | 800-1000 USD/Tom |
| การบรรจุแบบมาตรฐาน: | ในชุดรวมหรือในกล่องไม้ |
| ระยะเวลาการจัดส่ง: | 20-30 วันสำหรับผลิตภัณฑ์ |
| ความสามารถในการจัดหา: | 60000 ตัน/ตันต่อปี |
High-tensile structural steel tubes designated under JIS G 3474 (“High strength steel tubes for steel tower”), grade STKT590. These tubes are manufactured primarily for use in transmission towers or other steel tower structures, offering elevated strength compared with standard structural steel tubes.
Standard: JIS G 3474
Grade: STKT590
Tube type: typically longitudinally welded tubes (electric-resistance welded or automatic arc welded) for steel towers
Applicable outside diameter range (typical): 139.8 mm to 1,117.6 mm in standard JIS specification.
Thickness: as per user agreement; for instance standard clause may allow up to ~25 mm thickness for the grade in table for “25 mm or less” in some editions.
High tensile strength: minimum tensile strength of 590 MPa and up to ~740 MPa.
Good yield strength: minimum proof/yield strength of 440 MPa.
Controlled chemical composition enabling reliable welding performance and structural stability (see next section).
Carbon equivalent limit (Cₑq ≤ 0.40 %) per JIS standard, promoting weldability.
Designed for tower structural usage — makes it ideal for lattice towers, transmission towers, guyed masts, etc.
As a factory-specialist producer of STKT590 tubes, we address key customer concerns from a manufacturing perspective:
Straightness and dimensional precision: Through continuous welded tube production with calibrated rolling, we ensure tube straightness within tight tolerances and flat end faces perpendicular to the axis, meeting the JIS requirement that “the tube shall be practically straight and both ends shall be square to the axis”.
Strict thickness and diameter tolerances: We adhere to the dimensional tolerances in the JIS standard (for outer diameter and wall thickness) and maintain internal production records—this reduces misalignment and improves fit-up on tower site. For example, for thickness ≥12 mm the tolerance is +15 % / −1.5 mm (for certain sizes) under JIS G 3474.
Reliable mechanical properties: Our internal QA ensures the minimum tensile strength (590–740 MPa) and minimum yield strength (≥440 MPa) are consistently met or exceeded, verified by coupon testing. This ensures that the tube can carry high loads as required in tower structures.
Controlled chemical composition and weldability: By limiting C ≤0.12 %, Si ≤0.40 %, Mn ≤2.00 %, P ≤0.030 %, S ≤0.030 %, Nb+V ≤0.15%, and B ≤0.0002 % in line with JIS G 3474 table 2, we ensure low inclusion levels, stable microstructure, and better weldability.
Tailored for tower fabrication: We cooperate with tower manufacturers to supply cut lengths, chamfered ends, weld bevels, or combinations of diameters and thicknesses per site drawings, facilitating efficient erection on site.
| Grade | C (max %) | Si (max %) | Mn (max %) | P (max %) | S (max %) | Nb+V (max %) |
|---|---|---|---|---|---|---|
| STKT590 | 0.12 | 0.40 | 2.00 | 0.030 | 0.030 | 0.15 |
| STKT540 | 0.23 | – | 1.50 | 0.040 | 0.040 | – |
| STKT520 (*) | – | – | – | – | – | – |
| STKR590 (rectangular tube grade) | – | – | – | – | – | – |
| API X70 (pipe grade for reference) | ~0.22 | ~0.30 | ~1.50 | ~0.025 | ~0.015 | – |
* Note: STKT520 is included for illustrative purposes though detailed composition may not be publicly documented in the same way.
Here is a table showing mechanical property minima for STKT590 plus comparable grades.
| Grade | Tensile Strength (Rm MPa) | Yield/Proof Strength (σs MPa) | Elongation (δ %) |
|---|---|---|---|
| STKT590 | 590-740 | ≥440 | ≥20 (for D>40 mm) |
| STKT540 | ~540 (approx) | ≥? | ≥? |
| STKT520 | (approx ~520) | – | – |
| A572 Grade 50 (ASTM) | 345-550 | ≈345 | 21 min |
| S355J2H (EN) | 470-630 | ≈355 | 22 min |
JIS G 3474: High strength steel tubes for steel tower (Japan)
Execution manufacturing methods per standard: manufacture by electric-resistance welding or automatic arc welding (straight seam) using fine-grain killed steel; no heat treatment typically required.
Chemical analysis by JIS G 0320, product analysis by JIS G 0321.
These tubes are used in tower structural applications, especially in transmission towers, power line towers, communications towers, wind-turbine tower components, or other lattice-structure towers requiring high strength and welded tubular members.
Fabrication of lattice tower legs (diagonal and vertical members) using STKT590 tubes to reduce weight and improve structural capacity compared to conventional tubes.
Horizontal members/bracing tubes in transmission towers where high tensile strength allows smaller section sizes and better economy.
Pre-fabricated welded sections for guyed masts or telecom towers where the tube must meet strict dimensional and straightness requirements.
In wind-tower applications (lower sections) where high strength tubes enable thinner walls and larger diameter for improved stiffness and structural efficiency.
A: manufacturer,also can do trading.
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock, it is according to quantity.
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.
