Technical standards for precision seamless hydraulic tubes

What is precision hydraulic seamless steel tube?

Precision seamless hydraulic tube made of precision cold drawn seamless steel tubes that are processed by black or gray phosphating process, and the phosphated steel tubes are sealed and rust-proofed.Hydraulic steel pipes are basically divided into fluid pipes and oil steel bobbins used in hydraulic systems, also known as honing pipes, and cold-drawn or cold-rolled precision seamless steel pipes also include hydraulic steel tubes.

Technical standards for hydraulic seamless steel tubes:

In the standard, it is DIN2391-1. The raw materials of hydraulic steel pipes are subjected to fine drawing, non-oxidizing bright heat treatment (NBK state), non-destructive testing, the inner hole of the steel pipe is washed and pickled under high pressure, the inner and outer walls of the steel pipe are treated with anti-rust oil, and the two ends are sealed as dust-proof treatment.The steel pipe produced has high precision and good smoothness. There is no oxide layer on the inner and outer walls of the steel pipe. The steel pipe can withstand the high pressure of liquid flow, and the steel pipe is not deformed by cold bending, and can be flared and flattened without cracks. The mechanical properties can be bent at any angle without deformation. It is mainly used to prepare steel pipes in the oil circuit of hydraulic systems, also called hard piping in hydraulic systems, precision steel pipes for automobiles, the specifications are generally outer diameter (D) Φ4mm-76mm, wall thickness (S) 0.5mm-6.0mm. The length is 6 meters (except for custom-made), and the delivery status is NBK (normalizing), GBK (annealing), BKS (stress relief annealing). The main materials used are ST35, ST37.4 (10#), ST45 (20#) ST55 (35#), ST52 (16Mn), etc., which can meet customer requirements for steel pipes with high precision, high finish, tensile strength,high mechanical performance requirements.

According to the European standard (EN10305-4: 2003), the standard hydraulic steel pipe is introduced: the precision hydraulic steel pipe produced is a precision cold drawn seamless pipe after removing the surface and internal stress through anaerobic tempering treatment, and then undergoing phosphating prevention Made of rust treatment. The product has high dimensional accuracy, good ductility, easy to process and bend into various required shapes without the tube section being reduced or flattened; the surface of the tube has high precision, the surface hardness is moderate after anaerobic tempering treatment, and it is easy to clamp the connection and the inner hole. And the surface can be installed directly without pickling and rust removal after phosphating antirust treatment.

Honing pipe: cold-rolled precision seamless steel pipe is a seamless steel pipe finished pipe or seamless pipe waste pipe, after pickling, phosphating, saponification treatment, and then rolled into a hydraulic steel pipe by a cold rolling pipe mill.

The precision of seamless hydraulic steel tube is extremely high, and it can generally be controlled within the range of 0.02-0.05mm. The standard is: GB3639-83, the allowable deviation of the inner diameter is 0.03mm, the inner surface roughness: Ra 0.2～0.8μm, the straightness of the hydraulic steel pipe: 0.3～1.5mm/m, specially used for oil steel cylinder diameter.