ASTM A217 C12A Material - API Pressure Seal Gate Valve

What is ASMT A217 Material?

ASTM A217/A217M covers one grade of martensitic stainless steel and nine grades of ferritic alloy steel which are primarily utilized in high-temperature and corrosive service. It includes C-Mo alloy steel: Grade WC1; Ni-Cr-Mo alloy steel: Grade WC4, WC5; Cr-Mo alloy steel: Grade WC6, WC9, WC11, C5, C12; Cr-Mo-V alloy steel: Grade C12A; and Chromium Steel: Grade CA15.

Chemical Composition Requirements of ASTM A217 Material

Grade	UNS	C	Mn	P	S	Si	Cr	Mo	Others
WC1	J12524	≤0.25	0.50-0.80	≤0.04	≤0.045	≤0.60	–	0.45-0.65	*A
WC4	J12082	0.05-0.20	0.50-0.80	≤0.04	≤0.045	≤0.60	0.50-0.80	0.45-0.65	*B
WC5	J22000	0.05-0.20	0.40-0.70	≤0.04	≤0.045	≤0.60	0.50-0.90	0.90-1.20	*C
WC6	J12072	0.05-0.20	0.50-0.80	≤0.035	≤0.035	≤0.60	1.00-1.50	0.45-0.65	*D
WC9	J21890	0.05-0.18	0.40-0.70	≤0.035	≤0.035	≤0.60	2.00-2.75	0.90-1.20	*E
WC11	J11872	0.15-0.21	0.50-0.80	≤0.020	≤0.015	0.30-0.60	1.00-1.50	0.45-0.65	*F
C5	J42045	≤0.20	0.40-0.70	≤0.04	≤0.045	≤0.75	4.00-6.50	0.45-0.65	*G
C12	J82090	≤0.20	0.35-0.65	≤0.035	≤0.035	≤1.00	8.00-10.00	0.90-1.20	*H
C12A	J84090	0.08-0.12	0.30-0.60	≤0.025	≤0.010	0.20-0.50	8.0-9.5	0.85-1.05	*H
CA15	J91150	≤0.15	≤1.00	≤0.040	≤0.025	≤1.50	11.5-14.0	≤0.50	*I

*All values are maximum unless otherwise specified.
*A – Total Residual{Cu:≤0.50,Ni:≤0.50,Cr≤0.35,W≤0.10}:≤1.00. *B – Ni:0.70-1.10,Total Residual{Cu:≤0.50,W≤0.10}:≤0.60.
*C – Ni:0.60-1.00,Total Residual{Cu:≤0.50,W≤0.10}:≤0.60. *D – Total Residual{Cu:≤0.50,Ni:≤0.50,W≤0.10}:≤1.00.
*E – Total Residual{Cu:≤0.50,Ni:≤0.50,W≤0.10}:≤1.00. *F – Total Residual{Al:≤0.01,Cu:≤0.35,Ni:≤0.50,V≤0.03}:≤1.00.
*G – Total Residual{Cu:≤0.50,Ni:≤0.50,W≤0.10}:≤1.00. *H – Total Residual{Cu:≤0.50,Ni:≤0.50,W≤0.10}:≤1.00.
*I – Ni:≤0.40,Co:0.06-0.10,N:0.03-0.07,V:0.18-0.25,Total Residual{Al:≤0.02,Ti≤0.01,Zr≤0.01}. *J – Ni:≤1.00.
*Values from *A to *J shall be furnished with the unit “%”.

Mechanical Properties of ASTM A217 Material

Grade	Tensile Strength, ksi[MPa]	Yield Strength, min. ksi[MPa]	Elongation in 2″, min. %	Reduction of Area, min. %
WC1	65[450]-90[620]	35[240]	24	35
WC4	70[485]-95[655]	40[275]	20	35
WC5	70[485]-95[655]	40[275]	20	35
WC6	70[485]-95[655]	40[275]	20	35
WC9	70[485]-95[655]	40[275]	20	35
WC11	80[550]-105[725]	50[345]	18	45
C5	90[620]-115[795]	60[415]	18	35
C12	90[620]-115[795]	60[415]	18	35
C12A	85[585]-110[760]	60[415]	18	45
CA15	90[620]-115[795]	60[415]	18	30

What is C12A Material?

C12A material is martensitic chromium-molybdenum steel, suitable for pressure-containing parts.

ASTM A217 C12A API Pressure Seal Gate Valve

Pressure seal gate valves are used for high-pressure service, typically for pressures above 100 bar. The unique feature of the pressure seal bonnet is that the body-bonnet joints seal improves as the internal pressure within the valve increases.