ASTM A387 Grade 9 Class 1 chromium-molybdenum pressure vessel steel plate, 9Cr-1Mo, SHH STEEL

ASTM A387 Grade 9 Class 1 Steel Plate | A387 Gr.9 Cl.1 9Cr-1Mo Vessel Plate

ASTM A387 Grade 9 Class 1 / A387 Gr.9 Cl.1 is 9Cr-1Mo pressure-vessel plate. Tensile is 415–585 MPa and yield is 205 MPa min. SHH STEEL supplies A387GR9CL1 worldwide as a global steel mill sourcing partner.
Keywords
ASTM A387 Grade 9 Class 1, A387 Gr.9 Cl.1, A387GR9CL1, A387GR9 CL1, SA387 Grade 9 Class 1, 9Cr-1Mo vessel plate, A387 Gr.9 Cl.1 supplier
Equivalent Grades:
N 10028-2 X10CrMoVNb9-1 (near, Gr9 is non-V) / JIS SCMV9 (near) / GB 12Cr9Mo (near) — Material Specification: ASTM A387 / ASME SA-387 — Delivery: Normalized + Tempered (N+T)
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General Description
Material Specification
Chemical Composition
Mechanical Properties
Material Comparison
Equivalent Material Grades
9Cr-1Mo Elevated-Temperature Service
Weldability
Heat Treatment and Delivery Condition
Dimensions
Tolerances
Supplementary Requirements
Applications
Supply Capability
Global Delivery & Markets
Why Choose SHH STEEL
FAQ
Conclusion

What is ASTM A387 Grade 9 Class 1 Steel?

ASTM A387 Grade 9 Class 1, also searched as A387 Gr.9 Cl.1, A387GR9CL1, A387GR9 CL1, A387GR.9 Class 1, A387-9 Cl.1 and SA387 Grade 9 Class 1, is the lower-strength class of Grade 9 in ASTM A387/A387M. The book is chromium-molybdenum plate for welded boilers and elevated-temperature vessels. Nominal alloy is 9.00Cr-1.00Mo. This page is not Class 2. Class 2 is 515–690 MPa. This page is not ASME SA387 Grade 91 Class 2. Grade 91 is 9Cr-1Mo-V-Nb. This page is not ASME SA387 Grade 5 Class 1. Grade 5 is 5Cr-0.5Mo. This page is not EN 10028-2 X10CrMoVNb9-1. That grade is P91.

Tensile is 60–85 ksi / 415–585 MPa. Yield is 30 ksi / 205 MPa min. Delivery is thermally treated: annealed, normalized and tempered, or accelerated cooling plus temper. Minimum temper for Grade 9 is 1250 °F / 675 °C. SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin). We buy this grade from qualified Chinese mills, check the certificate against A387 / SA-387 and A20 / SA-20, and ship it to fabricators in the USA, Europe, Middle East, Southeast Asia, Africa and South America.

If a drawing says A387 Gr.9 Cl.2, we will not ship Class 1 and call 415 enough. For ASME Code work the name on the certificate should be SA-387 Grade 9 Class 1. Related category pages: ASTM A387 and ASME SA387.

Material Specification

Specification ElementRequirementSHH STEEL Compliance
Grade / classASTM A387/A387M Grade 9 Class 1Confirmed
Code counterpartASME SA-387 Grade 9 Class 1Available
Other search namesA387 Gr.9 Cl.1, A387GR9CL1, A387GR9 CL1Covered
Steel typeKilled 9Cr-1Mo vessel plateConfirmed
Usual deliveryAnnealed or N+TConfirmed
Tensile415–585 MPa (60–85 ksi)Confirmed
Yield205 MPa (30 ksi) minConfirmed
Supply roleGlobal steel mill sourcing partnerSHH STEEL
CertificationEN 10204 3.1 or 3.2 / third-partyAs ordered

This plate sits in pressure vessel steel plates and ASTM A387. European 9Cr sisters belong on EN 10028-2.

Chemical Composition

Heat analysis and product analysis follow ASTM A387 Table 1 for Grade 9. Class 1 and Class 2 share the same chemistry.

Heat Analysis and Product Analysis — ASTM A387 Grade 9

ElementHeat Analysis (%)Product Analysis (%)
Carbon (C), max0.150.15
Manganese (Mn)0.30 – 0.600.25 – 0.66
Phosphorus (P), max0.0250.025
Sulfur (S), max0.0250.025
Silicon (Si)0.25 – 1.000.13 – 1.05
Chromium (Cr)8.00 – 10.007.90 – 10.10
Molybdenum (Mo)0.90 – 1.100.85 – 1.15

Grade 9 is not Grade 91. Grade 91 adds vanadium, niobium and nitrogen and uses a different tensile table. Do not treat ASME SA387 Grade 5 Class 1 as Grade 9. SHH STEEL prints heat analysis on every certificate and product analysis when ordered. Density is 7.85 g/cm³.

Mechanical Properties

Buyers search A387 Gr.9 Cl.1 mechanical properties, A387GR9CL1 yield and A387 Grade 9 Class 1 tensile.

Tensile and Yield — ASTM A387 Grade 9 Class 1

ItemRequirement
Tensile strength60–85 ksi / 415–585 MPa
Yield strength, min30 ksi / 205 MPa
Elongation in 2 in. [50 mm], min18%
Reduction of area, min40%
Density7.85 g/cm³

Class 2 on the same grade is 75–100 ksi / 515–690 MPa with 45 ksi / 310 MPa yield. Do not quote Class 2 numbers on a Class 1 order.

Material Comparison

GradeBookWhat buyers searchSwap?
ASME SA387 Grade 5 Class 1SA-387SA387 Gr.5 Cl.1No
ASTM A387 Grade 9 Class 1A387A387 Gr.9 Cl.1 / A387GR9CL1This page
ASTM A387 Grade 9 Class 2A387A387 Gr.9 Cl.2No
ASME SA387 Grade 9 Class 1SA-387SA387 Gr.9 Cl.1Code name
ASME SA387 Grade 91 Class 2SA-387SA387 Gr.91 Cl.2No
EN 10028-2 X10CrMoVNb9-1EN 10028-2P91 / X10CrMoVNb9-1No
EN 10028-2 X12CrMo5EN 10028-2X12CrMo5No

Equivalent Material Grades

There is no official one-to-one worldwide swap for A387 Gr.9 Cl.1. What buyers compare is the 9Cr-1Mo idea in other books, not an automatic substitute.

In the United States the Code name is ASME SA-387 Grade 9 Class 1. That is the same chemistry and the same Class 1 tensile table. ASTM A387 Grade 9 Class 2 is the same chemistry at the higher strength class. ASME SA387 Grade 91 Class 2 is 9Cr-1Mo-V-Nb, not Grade 9.

In Europe there is no daily 9Cr-1Mo twin without vanadium. X10CrMoVNb9-1 / P91 is the Grade 91 family. X12CrMo5 is 5Cr-0.5Mo. Both sit on EN 10028-2.

In China there is no daily GB/T 713 twin that buyers treat as Grade 9. 12Cr2Mo1R is 2.25Cr-1Mo. See 12Cr2Mo1R.

DesignationCountry / regionStandardNotes
ASTM A387 Gr.9 Cl.1 / A387GR9CL1USAASTM A387Name on this page
ASME SA-387 Grade 9 Class 1USASA-387Code counterpart
ASTM A387 Grade 9 Class 2USAA387Same chemistry, higher class
ASME SA387 Grade 91 Class 2USASA-3879Cr-1Mo-V-Nb
ASME SA387 Grade 5 Class 1USASA-3875Cr-0.5Mo sister
EN 10028-2 X10CrMoVNb9-1EuropeEN 10028-2P91, not Grade 9
EN 10028-2 X12CrMo5EuropeEN 10028-25Cr-0.5Mo

Dual marking is possible only when both books are fully met.

9Cr-1Mo Elevated-Temperature Service

Buyers pick A387 Gr.9 Cl.1 when a file wants 9Cr-1Mo at the Class 1 strength band. Search phrases such as A387GR9CL1, A387 Grade 9 Class 1 and SA387 Grade 9 Class 1 all point here.

It is not a substitute for ASME SA387 Grade 91 Class 2. That grade is P91 chemistry. It is not a substitute for ASME SA387 Grade 5 Class 1. That grade is 5Cr. Dual marking with SA-387 Grade 9 Class 1 is the normal Code route.

SHH STEEL supplies this plate to fabricators in the United States, Mexico, South America, Europe, the Middle East, Africa and Asia.

Weldability

A387 Grade 9 Class 1 is killed 9Cr-1Mo vessel plate. Treat welding as production welding, and as ASME Section VIII / PED welding when the equipment is a vessel.

Qualify to the applicable code. Consumables must match a 9Cr-1Mo family. A procedure written for ASME SA516 Grade 70 is the wrong alloy. A procedure written for ASME SA387 Grade 91 Class 2 is a P91 procedure, not Grade 9. Preheat, interpass and PWHT must stay inside the qualified WPS. Minimum temper on the plate is 675 °C. The fabricator owns the WPS. SHH STEEL can share mill heat data for that review.

Heat Treatment and Delivery Condition

Usual delivery from SHH STEEL for A387 Gr.9 Cl.1 is annealed or normalized and tempered. Accelerated cooling plus temper is allowed when the mill route needs it. Minimum tempering temperature for Grade 9 is 1250 °F / 675 °C.

Class 2 tensile values are not applicable to annealed plate. If the drawing says Class 2, do not ship an annealed Class 1 heat and call it close.

If the vessel will see PWHT, say so. Simulated PWHT on test coupons is worth naming on 9Cr work. Extra simulation, 3.2 hold points or special NDE add time. Plan about two months when those extras are on the order.

The certificate lists ASTM A387 Grade 9 Class 1 and, when ordered, ASME SA-387 Grade 9 Class 1; heat number; heat analysis; product analysis when ordered; tensile to the Class 1 table; heat-treatment route. Certificates may be EN 10204 3.1 or EN 10204 3.2.

Dimensions

Usual supply range from SHH STEEL for A387 Gr.9 Cl.1 9Cr-1Mo vessel plate:

  • Thickness: commonly 6 mm – 150 mm, thicker by mill agreement
  • Width: 1500 mm – 4000 mm
  • Length: 3000 mm – 12000 mm

Maximum thickness is limited by the ability of the composition to meet Class 1 tensile. P91 plate belongs on ASME SA387 Grade 91 Class 2. 5Cr plate belongs on ASME SA387 Grade 5 Class 1.

Tolerances

 

Dimensional limits for ASTM A387 Grade 9 Class 1 follow ASTM A20 / ASME SA-20 unless the purchase order names another table. Do not apply ASTM A36 structural tolerances to a Cr-Mo vessel plate without writing them.

Typical thickness tolerance idea for A387 Gr.9 Cl.1 (A20 / SA-20 reference)

Nominal thickness (mm)Usual minus (mm)Usual plus (mm)
6 – 16−0.3+0.8
16 – 25−0.4+0.9
25 – 40−0.5+1.0
40 – 80−0.8+1.2
80 – 150−1.0+1.6

Width on 1500–4000 mm plate is commonly held to about ±20–25 mm unless the mill quote names a tighter extra. Length on 3000–12000 mm plate is commonly held to about +50 / 0 mm or ±25 mm by mill practice. Flatness follows A20 / SA-20 unless a tighter class is written. Edge condition is mill edge or cut edge as ordered. If the vessel calculation used minimum thickness after corrosion, write the allowed minus on the RFQ. SHH STEEL will not assume a zero-minus extra on A387GR9CL1 unless the order says so.

Supplementary Requirements

ASTM A387 Grade 9 Class 1 already defines chemistry, Class 1 tensile and the 675 °C minimum temper. Extra items still have to be written on the purchase order. SHH STEEL will not assume them from the grade name alone.

Code name. Write SA-387 Grade 9 Class 1 when the equipment is ASME Code work.

Heat-treatment route. Write annealed, normalized and tempered, or accelerated cooling plus temper. Do not leave it as “as-rolled.”

Charpy details. Class 1 does not assume a default impact temperature. Write temperature, joules, location and orientation if impact is required.

Simulated PWHT. When the vessel will be stress-relieved, name hold temperature, hold time and cooling rate on the coupon.

Product analysis. Especially C, Cr, Mo, Si, P and S.

Through-thickness / Z-test. Name Z15, Z25 or Z35 when the plate will be welded in the thickness direction.

NDE. A20 / SA-20 ultrasonic extras, ASTM A435 or ASTM A578 as named. Write scanning extent and acceptance class.

Hardness. If the destination file caps hardness after heat treatment or after simulated PWHT, write the max HB and the test location.

HIC / SSC / NACE. Only when the equipment is sour service. A387 Gr.9 Cl.1 is not automatically NACE MR0175 / ISO 15156.

Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS, CCS, DNV or the inspector named. Hold points for heat treatment, chemistry, tensile and UT should be listed on the ITP.

Identification and stamping. Heat number, grade A387 Grade 9 Class 1 / A387 Gr.9 Cl.1, SA-387 Grade 9 Class 1 when ordered, thickness and mill logo on each plate.

Applications

IndustryTypical components
9Cr-1Mo boilersA387 Gr.9 Cl.1 / A387GR9CL1 shells
Elevated-temp vesselsA387 Grade 9 Class 1 courses from SHH STEEL
ASME Code dual-nameA387 Gr.9 Cl.1 / SA-387 Grade 9 Class 1
Comparison vs P91A387GR9CL1 next to ASME SA387 Grade 91 Class 2

A387 Grade 9 Class 1 is the plate for a file that wants 9Cr-1Mo at the lower strength class. It is the wrong plate for Class 2 tensile. That work is A387 Grade 9 Class 2. It is the wrong plate for P91. That work is ASME SA387 Grade 91 Class 2.

Supply Capability

SHH STEEL sources ASTM A387 Grade 9 Class 1 from first-line Chinese mills and ships it on worldwide terms. Partner mills include Wuyang (Wugang), Angang, Shougang, Hanye, Anyang Iron & Steel, Baosteel, Xinyu, Xingcheng, Yongjin, Tsingshan, TISCO (Taiyuan), Jiuquan (JISCO), Lianzhong, Zhangpu and Baoxin, plus other qualified mills when the size or heat-treatment route requires it.

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.

Usual stock and rolling thickness: 8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 30 mm, 32 mm, 36 mm, 40 mm, 50 mm, 60 mm, 80 mm, 100 mm, thicker by mill agreement.

Processing: CNC or flame cutting, bevel, flattening, UT to the named class.

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.

Global Delivery & Markets

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 plates 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; standard rolling / heat treatment about 45–60 days; simulated PWHT / 3.2 about 2 months.

Why Choose SHH STEEL

Experience on this grade is simple: keep Grade 9 away from Grade 91 and Grade 5, and keep Class 1 away from Class 2. SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) prices A387 Gr.9 Cl.1 from first-line mills, reports 9Cr-1Mo chemistry, records annealed or N+T delivery, and issues 3.1 as standard or 3.2 when specified.

We keep the grade on the order. A387GR9CL1 is not A387 Gr.9 Cl.2. A387 Grade 9 Class 1 is not ASME SA387 Grade 91 Class 2. A387 Gr.9 Cl.1 is not ASME SA387 Grade 5 Class 1. If the drawing says Class 2, we will not ship Class 1 and call 415 close.

FAQ

What is A387 Grade 9 Class 1 steel plate?
ASTM A387 Grade 9 Class 1, also searched as A387 Gr.9 Cl.1, A387GR9CL1 and SA387 Grade 9 Class 1, is 9Cr-1Mo pressure-vessel plate. Tensile is 415–585 MPa and yield is 205 MPa min. Delivery is annealed or normalized and tempered. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
What is the equivalent of A387 Gr.9 Cl.1?
The Code counterpart is SA-387 Grade 9 Class 1. P91 / X10CrMoVNb9-1 is Grade 91, not Grade 9. Dual marking is possible only when both books are fully met.
How is Class 1 different from Class 2 on Grade 9?
Class 1 is 415–585 MPa with 205 MPa yield. Class 2 is 515–690 MPa with 310 MPa yield. Chemistry is the same. Annealed plate is Class 1 only.
How is A387GR9CL1 different from Grade 91?
Grade 9 is 9Cr-1Mo. Grade 91 is 9Cr-1Mo-V-Nb with a different tensile table. Do not swap them.
Can SHH STEEL issue EN 10204 3.2 for A387GR9CL1?
Yes. EN 10204 3.1 is standard. EN 10204 3.2 is arranged with SGS, TÜV, BV, ABS, CCS, DNV or the inspector named on the order.

Conclusion

ASTM A387 Grade 9 Class 1 Steel Plate is 9Cr-1Mo pressure-vessel plate at 415–585 MPa tensile and 205 MPa yield. Whether the inquiry says ASTM A387 Grade 9 Class 1, A387 Gr.9 Cl.1, A387GR9CL1, A387GR9 CL1 or SA387 Grade 9 Class 1, SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) supplies plate with Grade 9 chemistry, Class 1 tensile, recorded heat treatment, and EN 10204 3.1 or 3.2 certification.

SHH STEEL supplies ASTM A387 Grade 9 Class 1 / A387 Gr.9 Cl.1 9Cr-1Mo Vessel Plate to the USA, Mexico, South America, Europe, the Middle East, Africa and Asia for work that actually names this grade and class.

Contact SHH STEEL for mill rolling, stock inquiry, cutting, bevel, 3.2 inspection or a worldwide quotation.

ASTM A387 Grade 9 Class 1 Steel Plate, A387 Gr.9 Cl.1, A387GR9CL1, 9Cr-1Mo vessel plate, A387 Gr.9 Cl.1 supplier, SHH STEEL

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