FARBO 20 - Tempered chrome silicon steel wire

Oil tempered spring wire - For static springs

trade, sales, commerce, marketing, distribution, oil tempered steel wire, tempered chrome silicon steel wire, oil tempered spring wire, tempered chrome silicon spring wire, static springs, EN 10270-2 FD CrSi, EN 10270-2 FDCrSi, DIN 17223/2 FD, DIN 50602, M method, coil end tested

In compliance with:
EN 10270-2 FD CrSi
DIN 17223/2 FD

Utilization:
Static springs

Diameters:
2.40 - 13.50 mm

Chemical composition:

C	Si	Mn	P	S	Cu	Cr
0.50 - 0.60	1.20 - 1.60	0.50 - 0.90	<0.03	<0.02	<0.12	0.50 - 0.80

Raw Material:
Wire rod from qualified international steelworks

Non metallic inclusions:
In compliance with DIN 50602, M method, for all kind of inclusions the maximum size is No. 2

Mechanical and technological properties:

Nominal diameter (a < Ø ≤ b) [mm]	Allowed deviations (±) [mm]	Tensile strength [N/mm²]	Minimum reduction [Z %]	Minimum number of twists Lo = 50 × d Min. 100% Right - Left
2.40 - 2.50	0.025	1970 - 2140	45	to be agreed upon
2.50 - 2.70	0.025	1950 - 2120	45	to be agreed upon
2.70 - 3.50	0.030	1930 - 2100	45	to be agreed upon
3.00 - 3.20	0.030	1910 - 2080	45	to be agreed upon
3.20 - 3.50	0.030	1900 - 2060	42	to be agreed upon
3.50 - 4.00	0.030	1870 - 2030	42	to be agreed upon
4.00 - 4.20	0.035	1860 - 2020	40	to be agreed upon
4.20 - 4.50	0.035	1850 - 2000	40	to be agreed upon
4.50 - 4.70	0.035	1840 - 1990	40	to be agreed upon
4.70 - 5.00	0.035	1830 - 1980	40	to be agreed upon
5.00 - 5.60	0.035	1800 - 1950	38	to be agreed upon
5.60 - 6.00	0.040	1780 - 1930	38	to be agreed upon
6.00 - 6.50	0.040	1760 - 1910	35	to be agreed upon
6.50 - 6.00	0.040	1740 - 1890	35	to be agreed upon
7.00 - 8.00	0.045	1710 - 1860	35	not expected
8.00 - 8.50	0.045	1700 - 1850	32	not expected
8.50 - 10.00	0.050	1660 - 1810	32	not expected
10.00 - 12.00	0.070	1620 - 1770	30	not expected
12.00 - 13.50	0.080	1580 - 1730	30	not expected

• Allowed depth of surface defects at the coil ends: max. 1.5% of wire diameter
• Allowed depth of surface decarburisation at the coil ends: max. 1.5% of wire diameter
• Maximum permissible tensile strength variation within one coil: 60 N/mm²
• Out of roundness: i.e. the difference between the maximum and minimum diameter of the wire at the same cross section is not more than 50% of the total permissible deviation in the diameter
• Yield point (limit 0.2%): minimum 90% of tensile strength
• Elastic modulus: E = 206 kN/mm² (nominal value)
• Shear modulus: G = 79.5 kN/mm² (nominal value)
• Heat treatment: after the coiling the springs should be stress relieved at T = 420 ± 5°C for 30 min; after shoot peening should be stress relieved at T = 250 ± 10°C for 30 min