What is hydraulic tube?

Posted by zora li on February 21st, 2023

What is hydraulic tube?

Hydraulic steel pipes are basically divided into fluid pipes for hydraulic systems and steel pipes for oil, also known as honing pipes. Hydraulic seamless low-carbon steel pipes are one of them, and cold-drawn or cold-rolled precision seamless steel pipes also include hydraulic steel pipes.

Seamless precision tubes are used in the manufacture of mechanical structures or hydraulic equipment, etc. Precision steel pipe is a high-precision seamless steel pipe processed by cold drawing or cold rolling. Due to the characteristics of no oxide layer on the inner and outer walls of precision steel pipes, no leakage under high pressure, high precision, high finish, no deformation in cold bending, no cracks in flaring and flattening, it is mainly used for the production of pneumatic or hydraulic products.

Common technical standards:

DIN2391-1: The raw materials of hydraulic steel pipes have been fine-drawn, non-oxidative bright heat treatment (NBK state), non-destructive testing, the inner hole of the steel pipe is cleaned and pickled by high pressure, the outer wall of the inner hole steel pipe is treated with anti-rust oil, and both ends are sealed for dust-proof treatment. The steel pipe produced has high precision and good finish. There is no oxide layer on the inner and outer walls of the steel pipe. The steel pipe can withstand the high pressure that the liquid flows through. The steel pipe is cold-bent without deformation, and can be expanded and flattened without cracks. Mechanical properties can be bent at any angle without deformation. It is mainly used to prepare steel pipes in the oil circuit of the hydraulic system, and is also called hard piping in the hydraulic system. Precision steel pipes for automobiles generally have an outer diameter (D) of Φ4mm-76mm and a wall thickness (S) of 0.5mm-6.0mm. The length is 6 meters (except customized), 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 the requirements of high precision, high finish, and tensile strength of steel pipes. high.

European standard EN10305-4: The precision hydraulic steel pipe produced is a precision cold-drawn seamless pipe that undergoes anaerobic tempering treatment to eliminate surface and internal stress, and then undergoes phosphating and anti-rust treatment. The product has high dimensional accuracy, good ductility, and is easy to process. It can be bent into various desired shapes without diameter reduction or flattening; the pipe has high surface accuracy and is treated with anaerobic tempering. The surface hardness is moderate, and it is easy to match with ferrules and Bore connection. And after the surface is phosphating and anti-rust, it can be installed directly without pickling and rust removal.