Definition: A piston rod is a slender shaft component used to connect a piston and a crosshead (or other part of mechanical equipment), transmitting forces acting on the piston and driving its movement.
effect:
Convert hydraulic energy (or pneumatic energy) into mechanical energy to achieve motion control of mechanical equipment.
In hydraulic cylinders, the piston rod completes various work tasks by reciprocating motion, pushing or pulling the load.

Strength and stiffness: The piston rod must have sufficient strength and stiffness to withstand pressure and impact during operation, maintain shape stability, and prevent deformation.
Wear resistance: The surface of the piston rod should be smooth and have good wear resistance to reduce friction and wear with other components and extend its service life.
Machining accuracy: The machining accuracy of piston rods requires high precision, including coaxiality, straightness, etc., to ensure accurate transmission of force.
Connection reliability: The connection between the piston rod, piston, crosshead and other components must be reliable to prevent loosening and ensure the stable operation of the system.
Easy disassembly and assembly: The design of the piston rod should facilitate the disassembly and assembly of the piston for maintenance and repair.

Common materials: The commonly used materials for piston rods include 45 # steel, 40Cr steel, stainless steel (such as 304, 316, 402), etc.
Heat treatment: In order to improve the surface hardness, wear resistance, and fatigue strength of the piston rod, heat treatment processes such as quenching, tempering, and chrome plating are often used. For example, after quenching and tempering treatment, the surface of the 45 # steel piston rod can be turned, ground, and then chrome plated with a thickness of 0.03~0.05mm, which can significantly improve its service life.

Rolling processing: Rolling processing is an efficient and high-quality process measure that forms a cold work hardening layer on the surface of the piston rod to reduce the elastic and plastic deformation of the grinding contact surface, improve wear resistance, and delay the generation or expansion of fatigue cracks.
Precision cold drawing and polishing: Stainless steel piston rods often use precision cold drawing, precision grinding, high-precision polishing and other processes to ensure that their various technical indicators meet and exceed national standards.

Hydraulic system: Piston rods are used in hydraulic equipment to transmit pressure and drive mechanical actions, and are applied in fields such as engineering machinery, automotive manufacturing, plastic machinery, packaging machinery, printing machinery, etc.
Automotive industry: Piston rods can be used in the suspension and power steering systems of automobiles to enhance vehicle stability and handling.
Other machinery: In textile machinery, conveyor machinery and other equipment, piston rods also play an important role.

Inappropriate size: If the size of the piston rod is too small, it will reduce its strength, leading to bending or fracture; If the size is too large, it may increase the weight of the hydraulic cylinder and reduce the retraction force. The size should be accurately calculated based on actual needs.
Thread fracture: Poor thread machining quality or incorrect selection of thread specifications may lead to fracture. Suitable thread specifications should be selected and machining quality should be ensured.
Scratches and corrosion: Impurities mixed in hydraulic oil, failure of dust seals, etc. may cause scratches on the piston rod; Corrosion may occur when operating in humid or hazardous chemical environments. Hydraulic oil should be kept clean, damaged seals should be replaced in a timely manner, and suitable materials should be selected.
Deformation: When subjected to long-term eccentric load or lateral force, the piston rod may undergo bending deformation. The hydraulic cylinder structure should be designed reasonably to avoid unbalanced loads and lateral forces.

Regular inspection: Regularly check the operating status of the piston rod, including surface wear, scratches, corrosion, and other conditions.
Cleaning and lubrication: Maintain the cleanliness of hydraulic oil and replace it regularly; Lubricate the piston rod to reduce friction and wear.
Timely repair: When damaged or faulty piston rods are found, they should be repaired or replaced in a timely manner to ensure the normal operation of the hydraulic system.