Hydraulic Cylinder Steel Tube

Instruction

Production Method:
TORICH is a manufacturer and export for Hydraulic Cylinder Steel Tube, which is the main hydraulic cylinder honed tube suppliers from China
Hydraulic Cylinder Steel Tube, is usually produced by hydraulic cylinder barrel honing process based on Precision Seamless Steel Tube as raw material, production method can be ID Honed or Skiving Roller Burnished.
Hydraulic Cylinder Pipe is usually based on hydraulic cylinder barrel material according to EN10305-1 42CrMo4, induction hardened.

 

Chemical Composition Analysis, the element component tolerance referring to EN10083-3 standard.

C %	Si%	Mn%	S%	Cr%	Mo%
0.42	0.25	0.8	0.02	1.05	0.2

 

Mechanical Properties:

Size(mm) Outdiameter	Yield Strength ReH N/mm²	PSI	Tensile Strength Rm N/mm²	Elongation A5%
Up to 40	≥750	≥100000	＞1000	Min10%
＞40-100	≥635	≥90000	＞830	Min11%
＞100-160	≥550	≥80000	＞800	Min13%
＞160	≥550	≥80000	＞800	Min13%

 

Equivalent Steel for 42CrMo4

EN	DIN	AFNOR	SAE/ASTM	Chinese	BS
42CrMo4+QT	42CrMo4V	42CD4	4140	42CrMo	708M40

 

Chrome Layer:
Diameter ＞20mm, the chrome layer is 20μm min,for smaller sizes the minimum thickness is 15μm.

Surface Roughness:
The surface roughness (Ra) is less than 0.2μm and normally in the average of 0.05-0.15μm, the Rt is less than 2.0μm and with an average of 0.5-1.5μm.

Surface Hardness:
The chrome layer hardness is 900 HV 0.1min

42CrMo4+QT Hydraulic Cylinder Steel Tube surface hardiness: about 57HRC,
With hardness depth of 1.1mm to 3.0mm.

Straightness:
The diameter ＜30mm, the max deviation is less than 0.5/1000mm.
The max deviation for lager diameter is 0.3/1000mm.
Can consult and discuss with our team if special request is needed by customer.

Roundness:
The roundness us max 50% of the diameter tolerance range.

Diameter Tolerance:
ISO-f7 standard.
Other tolerance can be supplied by customers’ specific request.

Corrosion Resistance:
The chromium layer generated in hard-chrome plating process contains micron cracks, our products are made by controlled distribution of cracks. Special pre-finish surface and polishing after chroming ensure a very high corrosion resistance. The corrosion resistance for hard chrome plated bars are based on a salt spray test following ISO9227 standard with ISO10289.

 

Salt Spray Test Standards are following:

NSS	B117	SS	Neutral
AASS	B287	ESS	Acetic Acid
CASS	B368	CASS	Copper-accelerated acetic acid

 

Production Process for hydraulic honed tube:
Cold Drawn or Hot Rolled Seamless Steel Tubes →
Cold Drawing/Cold Rolling  →
Heat Treatment Annealing/Bright Annealing → (Repeat)
ID Honing or ID Roller Burnish → (Repeat) to final dimensional tolerances and ID roughness
Induction Hardened → Chrome Plating →
Final inspection → Ready to Ship

 

Tolerances from ISO286 for f7 in μm

ID mm	Upper	Lower
Upto 18	-16	-34
＞18-30	-20	-41
＞30-50	-25	-50
＞50-80	-30	-60
＞80-120	-36	-71
＞120-180	-43	-83
＞180-250	-50	-96
＞250	Consult our sales team

 

Delivery Length:
Production capability for length is 3.0-10 m.
Cutting to short length is achievable by customer’s specific requirement.

 

Workshop for Honed Tube for Hydraulic Cylinder:

Products Show from mass production:

Inspection and Testing:

Delivery and Packing: