The comparison is approximate
These grades are approximate equivalents, not identical materials. Their minimum values, test methods and heat treatment conditions differ. The standard named on your drawing always governs, and any substitution needs your written approval.
How to read the grade names
- ZG270-500 (GB/T 11352): ZG stands for cast steel; minimum yield strength 270 MPa, minimum tensile strength 500 MPa.
- ASTM A216 WCB / WCC: carbon steel casting grades with a tensile strength range of 70–95 ksi (485–655 MPa). WCC has a higher minimum yield than WCB.
- ГОСТ 977 25Л: 25 is the average carbon content in hundredths of a percent (about 0.25%); Л marks a casting steel.
Cast carbon steel comparison chart
Scroll sideways to compare grades
| Grade | Standard | Min. yield | Tensile | Min. elongation | Min. reduction of area |
|---|---|---|---|---|---|
| WCB | ASTM A216 (USA) | 250 MPa (36 ksi) | 485–655 MPa (70–95 ksi) | 22% | 35% |
| WCC | ASTM A216 (USA) | 275 MPa (40 ksi) | 485–655 MPa (70–95 ksi) | 22% | 35% |
| ZG230-450 | GB/T 11352 (China) | 230 MPa | 450 MPa min. | 22% | 32% |
| ZG270-500 | GB/T 11352 (China) | 270 MPa | 500 MPa min. | 18% | 25% |
| 25Л | ГОСТ 977 (Russia) | 235 MPa | 441 MPa min. | 19% | 30% |
ASTM A216 gives a tensile range (minimum and maximum); GB/T 11352 and ГОСТ 977 give minimums only. The 25Л values are for normalised, or normalised and tempered, castings (strength category К20) with walls up to 100 mm. Impact values are left out of this chart; if the part needs an impact test, state the test and temperature on the drawing.
25Л is an approximate equivalent for Russian drawings. Its minimum tensile strength (441 MPa) is lower than the 485 MPa of WCB, so a substitution in either direction needs approval.
What a WCB callout does not mean
A WCB callout does not imply pressure-vessel, valve, PED or API certification. WCB names the material grade and its properties. Any certification or approval a part needs is a separate requirement and must be stated in the RFQ.
WCC is used when the drawing calls for it. ASTM A27 grades are confirmed per drawing.
1020, 1045 and other wrought grades
Some RFQs for cast parts name 1020 or 1045, or GB 25#, 35# or 45#. These are wrought (rolled or forged) steel designations, used here as inquiry cross-references. They need a cast-versus-wrought check: JK reviews the drawing and agrees the cast steel grade with the buyer in writing before quoting.
What to put on the drawing or RFQ
- The full designation and the standard, for example “ASTM A216 WCB” or “ZG270-500 GB/T 11352”. “Carbon steel” on its own is not enough to quote against.
- Heat treatment, for example normalised, or normalised and tempered.
- Which tests are required: tensile, impact (with test temperature), hardness, and where the test bar comes from.
- Inspection documents: for example an EN 10204 3.1 material certificate with the chemical composition and test results.
- Whether equivalents are acceptable. If your drawing uses WCB and you will accept a GB grade, say so in writing.
How JK Casting supplies cast carbon steel
JK Casting makes carbon steel castings to customer drawings in Gaomi, Shandong, China, by sand casting and lost-wax investment casting, supplied raw or CNC-machined. Common carbon steel grades are ASTM A216 WCB (WCC when the drawing calls for it), ZG230-450 and ZG270-500, with ASTM A27 confirmed per drawing. Other grades on the drawing are reviewed part by part, and material records such as EN 10204 3.1 certificates are provided when agreed for the order.
Related pages: Carbon steel investment casting · Sand casting · Material selection · Send a drawing for quotation
Frequently asked questions
Is WCB the same as ZG270-500?
Not exactly. WCB requires 250 MPa yield, 485–655 MPa tensile and 22% elongation; ZG270-500 requires 270 MPa yield, 500 MPa tensile and 18% elongation. They are approximate equivalents, so the drawing’s standard governs and a substitution needs approval.
Does a WCB casting come with valve or pressure-equipment certification?
No. A WCB callout does not imply pressure-vessel, valve, PED or API certification. It names the material grade; any certification a part needs must be stated separately in the RFQ.
Can a part drawn in 1045 be cast?
1045 is a wrought steel designation, so it needs a cast-versus-wrought check. JK reviews the drawing and agrees a cast steel grade with the buyer before quoting.
What is the Russian equivalent of WCB?
ГОСТ 977 25Л is an approximate equivalent. Normalised, it requires 235 MPa yield, 441 MPa tensile and 19% elongation, which is lower than WCB’s 485 MPa minimum tensile strength.