Datong Hydraulic

  42CrMo   hard chrome plated steel bars   are chromium-plated steel products that can be supplied as   piston rods   in standard   hydraulic   and pneumatic applications. The hard chrome plated steel bar is normally used in conditions of high stress, friction and harsh climactic environments.so the quality of the base metal and subsequent surface treatment are of paramount importance. Wear resistance, corrosion resistance, surface smoothness, high yield strength and uniform quality are essential properties of hard chrome bar. Hard Chrome Rods are generally produced from steel bars combining high strength with excellent machinability and weldability. Common applications are found in agricultural machinery, production equipment, cranes, garbage compactors, lifters etc. 2.Steel Grade according to different standards   China steel grades: GB standard 42CrMo Germany steel grades: DIN standard 42CrMo4 Japanese steel grades: JIS standard SCM440 American steel grades: AISI Standard 4140  

  Cold drawing is the pulling of a hot rolled steel bar through a die that is slightly smaller in size.  So how is cold drawn steel made?  The process path that   Datong Hydraulic   uses consists of first shot blasting the hot rolled bar, then cold drawing it through the die, then rotary (roll) straightening, and finally cutting to length. Shot blasting: This initial operation will clean the surface of the hot rolled bar, essentially removing all scale and rust.  This operation also creates a bar surface which will help carry the drawing lubricant into the die. Cold drawing: The main operation, which actually produces the  cold drawn steel tube .  We use a heavy frame drawn bench which can draw out over 40′ long finished cold drawn bars.  The die itself is mounted securely so as not to move during operation.  A pusher mechanism will grab the bar and advance the first 12″ of the bar through the die.  Next a buggy carriage will grab the portion of the bar that’s sticking out through the

  Cylinder piston rod  is a connecting part that supports the piston to do work. It is mostly used in the hydraulic oil cylinder and cylinder movement execution part. It is a moving part with frequent movement and high technical requirements. Taking  hydraulic cylinder  as an example, it is composed of  cylinder barrel , piston rod (cylinder rod), piston and end cover. The quality of its processing directly affects the life and reliability of the whole product. After quenching and tempering treatment, the piston rod obtained good comprehensive mechanical properties and prepared for subsequent surface treatment. The purpose of surface quenching is to obtain high surface hardness to support the surface chrome-plated layer, so as to improve the wear resistance and corrosion resistance of piston rod. Stress relief annealing is arranged before electroplating after grinding to fully eliminate the residual stress inside the piston rod, improve the coating quality and product qualification rat

  The   honing tube   is rolled, because the residual compressive stress is left on the surface layer, which helps to close the tiny cracks on the surface and hinders the expansion of erosion. Thereby improving the surface corrosion resistance and delaying the generation or expansion of fatigue cracks, thus improving the fatigue strength of the honing tube. Through rolling forming, a layer of cold work hardening layer is formed on the rolling surface, which reduces the elastic and plastic deformation of the contact surface of the grinding pair, thus improving the wear resistance of the inner wall of the grinding tube and avoiding burns caused by grinding. After  rolling process , the reduction of surface roughness can improve the matching properties. Rolling is a kind of chip-free machining, which makes use of the plastic deformation of metal at normal temperature to flatten the micro-roughness of the workpiece surface, so as to change the surface structure, mechanical characteristics,

The  honing tube   is rolled, because the residual compressive stress is left on the surface layer, which helps to close the tiny cracks on the surface and hinders the expansion of erosion. Thereby improving the surface corrosion resistance and delaying the generation or expansion of fatigue cracks, thus improving the fatigue strength of the honing tube. Through rolling forming, a layer of cold work hardening layer is formed on the rolling surface, which reduces the elastic and plastic deformation of the contact surface of the grinding pair, thus improving the wear resistance of the inner wall of the grinding tube and avoiding burns caused by grinding. After  rolling process , the reduction of surface roughness can improve the matching properties. Rolling is a kind of chip-free machining, which makes use of the plastic deformation of metal at normal temperature to flatten the micro-roughness of the workpiece surface, so as to change the surface structure, mechanical characteristics, sh