Flapper Valve Steel

Stamping or punching shops and compressor manufacturers rely on valve flap steel for compressors that is fatigue-resistant and which can be easily processed. The quality of cooling units and air conditioners is based to a large extent on the quality and robustness of the valve flaps in the compressors. Baomit strip steel meets the demands made by compressor manufacturers and consumers on the quality of the valve flap material.

ParametersRecommendation
Thickness ToleranceT3
RoughnessClass 3
FlatnessClass 3
SurfaceWhite Polished
EdgesSlit / deburred
Hardness48 – 52 HRC
Steel GradeSK4, C100S, 1095, 95Cr1, 420J2, 440

Baomit Strip Steel for Flapper Valve

Our Advantages:

• Excellent fatigue resistance

• Excellent punching and stamping properties

• Precise thickness and width tolerances

• Maximum straightness deviation of 1 mm / 6 m

• Good surface finish

• Consistent, uniform microstructure

Steel Grades

Comparison of Norms
EU / ENUSA / AISIChemical Composition
C100S1095C: 0.95-1.05, Si: 0.15-0.35, Mn: 0.30-0.60, Ni: max 0.40, P: max 0.025, S: max 0.025, Cr: max 0.40, Mo: max 0.10
95Cr1/C: 0.90-1.00, Si: 0.15-0.30, Mn: 0.20-0.40, P: max 0.025, S: max 0.025, Cr: 0.30-0.40
SK4 – SK95MC: 0.90-1.00, Si: 0.10-0.35, Mn: 0.10-0.50, Ni: max 0.25, P: max 0.03, S: max 0.03, Cr: max 0.30, Cu: max 0.25
420J2C: 0.26-0.40, Si: max 1.0, Mn: max 1.0, Ni: max 0.60, P: max 0.04, S: max 0.03, Cr: 12.0-14.0

Thickness Tolerances

Thickness (mm)Tolerances ± mm
T1T2T3T4T5
0.020 – 0.0400.0040.0030.002
0.040 – 0.1000.0060.0050.0040.0030.002
0.100 – 0.1250.0070.0050.0040.0030.002
0.125 – 0.1600.0090.0060.0050.0040.003
0.160 – 0.2000.0100.0070.0050.0040.003
0.200 – 0.2500.0110.0080.0060.0040.003
0.250 – 0.4000.0150.0110.0080.0060.004
0.400 – 0.6000.0200.0140.0100.0070.005
0.600 – 0.8000.0230.0170.0120.0080.006
0.800 – 1.0000.0270.0190.0130.0090.007
1.000 – 1.2500.0340.0240.0170.0120.008
1.250 – 1.6000.0390.0280.020
1.600 – 1.7500.0460.0330.023

Width Tolerances

Thickness (mm)Width (mm)Tolerances ± mm
W1W2W3
≤0.25≤500.100.070.05
50 – 1250.150.110.07
>1250.200.150.10
0.25 – 0.50≤500.150.110.07
50 – 1250.200.150.10
>1250.250.200.15
0.50 – 1.00≤500.200.150.10
50 – 1250.250.200.15
>1250.300.250.15
1.00 – 1.60≤500.200.150.10
50 – 1250.300.250.15
>1250.350.250.20
1.60 – 1.75≤500.300.200.15
50 – 1250.350.300.20
>1250.400.300.20

Surface Roughness

Available in white polished, blue polished and yellow.

Thickness (mm)Roughness
Class 1Class 2Class 3
≤0.50Ra≤ 0.30 µm
Rt≤ 3.00 µm
Ra≤0.25 µm
Rt≤ 2.50 µm
Ra≤ 0.20 µm
Rt≤ 2.00 µm
0.50 – 1.00Ra≤ 0.35 µm
Rt≤ 3.50 µm
Ra≤ 0.25 µm
Rt≤ 2.50 µm
Ra≤ 0.20 µm
Rt≤ 2.00 µm
1.00 – 1.75Ra≤ 0.40 µm
Rt≤ 4.00 µm
Ra≤ 0.30 µm
Rt≤ 3.00 µm
Ra≤ 0.30 µm
Rt≤ 3.00 µm

Flatness Deviation

Maximum flatness deviation per inch strip width.

Thickness (mm)Flatness Deviation
Class 1Class 2Class 3Class 4
0.02 – 0.10P60P50P40P30
0.10 – 0.25P50P40P30P20
0.25 – 0.50P40P30P20P10
0.50 – 1.75P35P25P15P10

Straightness Deviation

Strip Width (mm)Measured Length (3m)
Class 1Class 2Class 3
≤503 mm2 mm1 mm
50 – 1253 mm2 mm1 mm
>1253 mm2 mm1 mm

Hubei Baomit Steel Materials Co., Ltd.

China Verified Manufacturer of Hardened and Tempered (H & T) Strip Steel