Application£º Used in making the coal mine hydraulic support and the pillar and other hydraulic equipment
Dmension Tolerances£º

Pipe S ize mm		Tolerances %
		Standard
OD D		¡À1
WT s	¡Ü20	¡À12.5
	>20	+12.5 - 10

Mechanical Properties£º

Grade	Sample Hat Treatment System	Tensile Strength ¦Òb Mpa	Yield Strength¦Ò0.2 Mpa	Elongation¦Äb %	Contraction ¦× %	Impact Energy Aku2 J	HB Hardness MAX
		MIN
20 35 45	¡ª¡ª	400 510 590	245 305 335	20 17 14	¡ª¡ª	¡ª¡ª	¡ª¡ª
27SiMn	920oC¡À20oC Water quenching 450oC¡À50o Temper coolant:oil or water	980	835	12	40	39	217

Chemical composition:

Grade	Chemical composition %
	C	Si	Mn	P	S	Cr	Ni	Cu	Nb	Re
				¡Ü
20	0.17~0.24	0.17~0.37	0.35~0.65	0.035	0.035	0.25	0.25	0.20	--	--
35	0.32~0.40	0.17~0.37	0.50~0.80	0.035	0.035	0.25	0.25	0.20	--	--
45	0.42~0.50	0.17~0.37	0.50~0.80	0.035	0.035	0.25	0.25	0.20	--	--
27SiMn	0.24~0.32	1.10~1.40	1.10~1.40	0.035	0.035	0.25	0.25	0.20	0.020~0.050	0.02~0.04

Products can be also supplied according to the standard of ASTM A519£¬ DIN 1629£¬ JIS G 3473.