ASTM A709 QST 70 Steel Shape | A709 QST 70 Bridge Shape Steel Supplier

ASTM A709 QST 70, also searched as A709 QST70, A709-QST70, A709 QST Gr.70, A913 Grade 70 and A709 QST 70 70ksi, is the 70 ksi quenched-and-self-tempered shape grade in ASTM A709/A709M. That book covers structural steel for bridges. QST 70 is built on A913/A913M Grade 70. It is rolled as W-shapes, not as a standard plate grade.

QST means the section is quenched from the rolling heat and self-tempers on the cooling bed. Carbon stays low so the 70 ksi shape still welds in production. That is not HPS 70W. HPS 70W is weathering QT plate. QST 70 is a painted A913 shape. QST 50 and QST 50S stay at 50 ksi. QST 65 stays at 65 ksi.

A certificate that only says A913 Grade 70 is not an A709 QST 70 member unless the purchase order also meets A709 toughness and identification. Do not treat QST 70 as A572 Gr.50 plate. Do not treat it as A36. Do not treat it as Grade 50W. A709 says HPS 70W and HPS 100W shall not be substituted for QST 70 without a written change of product form. Do not treat A709 as a pressure-vessel product. That work sits on ASTM A516 or pressure vessel steel plates.

General requirements follow A6/A6M. Yield is 70 ksi / 485 MPa min. Tensile is 90 ksi / 620 MPa min. Density is 7.85 g/cm³.

SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin). We source A709 QST 70 / A913 Grade 70 shapes from first-line Chinese mills, print heat and product analysis when ordered, record the impact zone when named, and ship sections to fabricators in the United States, Europe, the Middle East, Southeast Asia, Africa and South America.

Related category pages: structural steel plates, high strength low alloy plates, EN 10025-6 and EN 10025-3.

Nearby pages that buyers compare, but must not swap blindly, include EN 10025-6 S500QL, EN 10025-6 S460QL, EN 10025-3 S460NL and A514 Grade B.

QST 70 chemistry follows A913 Grade 70. Carbon is held down for welding after the QST cool. Heat analysis is the mill table. Product analysis, when ordered, follows A6 product tolerances on that heat.

Heat Analysis and Product Analysis — ASTM A709 QST 70 (A913 Gr.70 basis)

Carbon at 0.12% max is the A913 signature. HPS 70W plate uses a different Cu-Ni-Cr-Mo window. If the purchase order writes product analysis, SHH STEEL prints both columns.

Do not treat this chemistry as HPS 70W. Do not treat it as Grade 50W. Do not treat it as S355JR unless both books are met.

Buyers search A709 QST 70 mechanical properties, A709 QST70 yield, A913 Grade 70 and A709-QST70 tensile.

Tensile Properties — ASTM A709 QST 70 / A913 Grade 70 shapes

Toughness is the A709 extra. Write non-FCM or FCM, zone and temperature. A silent A913 Grade 70 heat is not an FCM shape.

Density is 7.85 g/cm³.

There is no official one-to-one worldwide twin for A709 QST 70. What buyers compare is a 485 MPa painted QST shape.

In the United States the process twin is A913 Grade 70. QST 65 stays at 65 ksi. HPS 70W is the 70 ksi weathering plate twin in name only. HPS 100W is 100 ksi plate.

In Europe compare S460QL, S500Q and S500QL. QST is not QT plate. See EN 10025-6.

In Japan compare SM570 for strength only. In China compare GB/T 1591 Q460 / Q500 routes. Dual mark only when both books are fully met.

Buyers pick A709 QST 70 when a painted W-shape wants 70 ksi yield, low carbon and an A709 stamp on an A913 route. Search phrases such as A709 QST70, A709 QST 70, A913 Grade 70 and A709-QST70 all point here.

It is the wrong product for an unpainted 70 ksi weathering flange. That work is HPS 70W plate. It is the wrong product for a 65 ksi QST file. That work is QST 65. It is the wrong product for a plate girder web. That work is an A709 plate grade. It is the wrong product for a pressure vessel. That work is A516 Grade 70.

SHH STEEL will ask for the W-depth before rolling.

ASTM A709 QST 70 is weldable low-carbon QST shape steel. Treat welding as 70 ksi bridge production welding when the member is FCM.

Typical consumables are matching 80–90 ksi low-hydrogen wires qualified on a 70 ksi A913 family. A procedure written for QST 65 is under-matched on yield. A procedure written for HPS 70W plate is a different chemistry family. A procedure written for S355JR is not a 70 ksi QST procedure.

Preheat follows flange thickness and hydrogen control. The fabricator owns the WPS. SHH STEEL can share mill heat data, product analysis and CEV for that review.

Usual delivery from SHH STEEL for A709 QST 70 is quenched and self-tempered A913 Grade 70 shapes. The mill quenches from the rolling heat. There is no separate furnace temper like HPS 100W plate.

Do not order QST 70 as QT A514 plate or as HPS 70W plate. The certificate lists ASTM A709 QST 70 and A913 Grade 70 when dual-marked; heat number; heat analysis and product analysis when ordered; tensile to the 70 ksi table; impact zone when ordered. Certificates may be EN 10204 3.1 or EN 10204 3.2.

Usual supply from SHH STEEL for A709 QST 70 bridge shape steel:

• Product form: QST W-shapes
• Depth range: common W14 to W36, other depths by enquiry
• Length: 6 m – 18 m, longer by enquiry

Plate girders stay on the A709 plate pages. Browse related plate sizes on structural steel plates, high strength low alloy plates and the products index.

Dimensional limits for ASTM A709 QST 70 follow A6 / A6M shape tolerances unless the purchase order names another table.

Flange width, depth, web thickness, out-of-square and camber follow the A6 W-shape tables. Length is commonly held to +50 / 0 mm or the A6 plus tolerance. Straightness follows A6 unless a tighter bridge extra is written. SHH STEEL will not assume a plate-thickness extra on a W-shape order.

QST 70 already defines the A913 70 ksi table and the QST route. Extra items still have to be written on the purchase order.

Book name. Write ASTM A709 QST 70. Write A913 Grade 70 as the dual mark.

Section size. Write the W designation.

Impact zone. Write non-FCM or FCM, zone and temperature.

Product analysis. Write it if the file needs the second chemistry column.

NDE. UT on flanges when named.

Identification and stamping. Heat number, A709 QST 70, size and mill logo.

Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS or the inspector named.

A709 QST 70 is the product for a painted 70 ksi QST shape file. It is the wrong product for an unpainted HPS flange. That work is HPS 70W plate. It is the wrong product for a QT 100 ksi flange. That work sits on A514 Grade Q or HPS 100W.

SHH STEEL sources ASTM A709 QST 70 from first-line Chinese section mills that run an A913 QST route and ships it on worldwide terms. Partner mills include Angang, Shougang, Maanshan, Laigang, Rizhao, Baotou and other qualified mills when the size requires it. Plate partners such as Wuyang, Hanye, Xinyu and Xingcheng cover A709 plate grades on the same project.

Mill test certificates are issued to EN 10204 3.1 as standard. EN 10204 3.2 is arranged when the order names a third-party hold point. Dual marking to A913 Grade 70 is the usual route.

Usual rolling: common W14–W36 depths, 12 m stock lengths, cut-to-length on request.

Processing: cutting, coping, drill, blast and paint, UT on flanges when named.

Trade terms: FOB Shanghai main, CIF destination available. Payment: TT, LC, or TT + LC.

Ocean time from Shanghai: US West 14–18 days; US Gulf 28–35 days; Rotterdam / Antwerp 28–35 days; Jebel Ali 18–25 days; Singapore 7–12 days; other ports quoted.

Third-party: SGS, TÜV, BV, ABS, CCS, GL, VL, DNV, RINA, NK, KR, or the inspector named.

SHH STEEL is a global steel mill sourcing partner with mill partnerships in China. We supply ASTM, ASME, EN, DIN, JIS and GB steel to buyers in the United States, Europe, the Middle East, Southeast Asia, Africa and South America. Origin is mill-direct, China origin.

SHH STEEL has supplied steel products to the USA, Mexico, Argentina, Peru, El Salvador, Spain, Netherlands, Germany, UAE, Saudi Arabia, South Africa, India, Thailand, Singapore, Vietnam, the Philippines, Japan and Korea.

Typical lead time: ex-stock 5–7 days when the section is in yard; standard QST rolling about 40–50 days; impact zone or 3.2 inspection about 50–60 days.

SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin). For A709 QST 70 that means mill-direct A913 price, not a multi-layer stockist mark-up on a 70 ksi QST heat. We buy from section mills that already run the low-carbon QST route, so the unit price stays competitive and the heat can still carry the A709 impact zone.

Delivery is short when the size is in range: ex-stock 5–7 days, standard heat about 40–50 days, 3.2 inspection about 50–60 days. Coping, drill, blast and paint can run in the same window. FOB Shanghai is the main term; CIF to US West, US Gulf, Rotterdam, Jebel Ali and Singapore is quoted on the same file.

Experience on this grade is simple: print A709 QST 70 and A913 Grade 70, keep carbon at 0.12% max, and do not ship HPS 70W plate as a W-shape. We will not skip the QST route on the certificate, will not stamp QST 65 as QST 70, and will not treat A709 as warehouse A36. If the file is unpainted 70 ksi plate, we will move the inquiry to HPS 70W and keep the price on the right product.

ASTM A709 QST 70 Steel Shape is 70 ksi / 485 MPa painted bridge shape steel built on A913 Grade 70 quench-and-self-temper practice, with A709 toughness when ordered. Whether the inquiry says ASTM A709 QST 70, A709 QST70, A709-QST70, A913 Grade 70 or A709 QST 70 70ksi, SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) supplies W-shapes with QST 70 chemistry, heat and product analysis as ordered, and EN 10204 3.1 or 3.2 certification.

SHH STEEL supplies ASTM A709 QST 70 / A709 QST70 Bridge Shape Steel to the United States, Europe, the Middle East, Africa, Asia and the Americas for work that actually names this grade.

Contact SHH STEEL for mill rolling, dual A913 marking, FCM impact, cutting, blast, 3.2 inspection or a worldwide quotation.

ASTM A709 QST 70 Steel, A709 QST70, A913 Grade 70, QST 70 bridge shape, A709 QST 70 supplier, SHH STEEL