Technical conditions for supercritical boiler plates of SA387Gr11CL2
1. Scope
The technical conditions apply to plates of SA387Gr11CL2 with thickness range 10mm-120mm use of Supercritical Boiler.
2. Adopt standard:
ASME SA387/SA387M Specification for pressure vessel plates, alloy steel, Chromium-Molybdenum
ASME SA20/SA20M Standard Specification for General Requirements for Steel Plates for Pressure Vessels
ASME SA370 Standard Test Methods and Definitions for Mechanical Testing of Steel Products
3. Dimension, Shape, Weight and Permissible Deviation
The dimension, shape, weight and permissible deviation shall meet the requirements of ASME SA20/SA20M.
The thickness toleration: -0.25mm/+3.5mm
4. Technical conditions
4.1 Chemical composition (Ladle analysis)
The chemical composition of plates shall be accordance with the following table 1.
Table 1 Chemical composition (Ladle analysis)
Thickness mm | C | Si | Mn | P | S | Ni | Cu | Cr | Mo | V | NB |
Ladle analysis | 0.05- 0.17 | 0.50- 0.80 | 0.40- 0.65 | Max 0.030 | Max 0.020 | Max 0.40 | Max 0.25 | 1.00- 1.50 | 0.45- 0.65 | Max 0.03 | Max 0.02 |
Product analysis | 0.04- 0.17 | 0.44- 0.86 | 0.35- 0.73 | Max 0.030 | Max 0.020 | Max 0.43 | Max 0.27 | 0.94- 1.56 | 0.40- 0.70 | Max 0.04 | Max 0.02 |
Note:
1) Ladle analysis sampling per furnace and product analysis per each PC finished product.
2) Mark "*" element V max 0.10% and Nb max 0.05% in the purchase order.
4.2 Steel making process: EAF+LF/VD
4.3 Mechanical properties
The mechanical properties of SA387Gr11CL2 shall meet the requirement as table 2&3.
Table 2 Tensile properties
Tensile TEMP | Yield strength MPa | Tensile strength MPa | Elongation % | Bend test D=3a |
Room Temp +20C | Min 310 | 515-690 | Min 22 | 180C un-cracked |
High Temp tensile test | Min 219 | Min 400 | Testing at +400 Celsius degree |
4.4 Impact properties
Impact test in the longitudinal and transverse for plates of SA387Gr11CL2 shall meet the requirements per table 3.
Table 3 Impact properties
Charpy-V Impact test Test temp. Celsius degree | Transverse | |
Average impact energy | ||
+20C | Min 31J |
4.5 Hardness: Max 22HRC
4.6 SWHT: Simulated Post-Weld Heat Treatment of Mechanical Test Coupons shall be prepared in 600+/-10 C with min.5 minute per each mm of thickness.
4.7 Surface quality
The surface quality of plates shall be accordance with ASTM A20/A20M.
4.8 Ultrasonic inspection
Plates shall be ultrasonic inspected per ASTM A578/A578M level C.
4.9 Test method and inspection rules
Test items, sampling quantity, sampling method and test method shall conform to table 4.
Table 4 Test items for plates
Test item | Quantity, Piece | Sampling method | Test method | Sampling conditions |
Ladle analysis | 1 (per furnace) | ASTM A20/A20M | ASME SA751 | / |
Tensile test | 1 (per rolled pc) | ASTM A20/A20M | ASME SA370 | SWHT |
Charpy-V impact test at +20C | 3 (per rolled pc) | ASTM A20/A20M | ASME SA370 | |
Product analysis | 1 (per rolled pc) | ASTM A20/A20M | ASME SA370 | +N |
Ultrasonic test | Each product pc | ASTM A578/A578M | ||
High TEMP tensile test | Each product pc | ASTM A20/A20M | ASME SA370 | SWHT |
5. Package, marking and certificate
Package, marking and certificate shall conform to A20.
6. The third party inspection
The chemical composition, tensile test and Charpy V impact test and HIC test for plates of SA387Gr11CL2 shall be witnessed by surveyor of client.
7. Delivery conditions
The delivery conditions for plates of SA387Gr11CL2 shall be Normalized(accept ACC)+ Tempered(temperature not less than 700 C degree.)
8. Other requirements
The other requirements for plates of SA387Gr11CL2 shall be accordance with SA387/SA387M-2010.
MTC accordance with EN10204: 2004 3.1