Piston Rod Processing Technology

2025-09-11

Using rolling processing, due to the residual compressive stress left on the surface layer, it helps to close small cracks on the surface and hinders the propagation of erosion. Thereby enhancing the surface corrosion resistance and delaying the generation or expansion of fatigue cracks, thus increasing the fatigue strength of the oil cylinder rod. By rolling forming, a cold work hardening layer is formed on the rolling surface, reducing the elastic and plastic deformation of the contact surface of the grinding pair, thereby improving the wear resistance of the cylinder rod surface and avoiding burns caused by grinding. After rolling, the decrease in surface roughness value can improve the fitting properties. At the same time, it reduces the friction damage to the sealing ring or seal during the movement of the cylinder rod piston, and increases the overall service life of the cylinder. Rolling technology is an efficient and high-quality process measure, and now taking the 160mm diameter mirror cutting rolling head (45 seamless steel pipe) as an example to prove the rolling effect. After rolling, the surface roughness of the oil cylinder rod decreased from Ra3.2-6.3um before rolling to Ra0.4-0.8um, the surface hardness of the oil cylinder rod increased by about 30%, and the surface fatigue strengt...

Key Manufacturing Processes Of Quenched And Tempered Piston Rods

2025-09-12

Key Manufacturing Processes of Quenched and Tempered Piston Rods The key manufacturing processes for quenched and tempered piston rods encompass six major steps: material selection, pre-treatment, quenching and tempering heat treatment, machining, surface treatment, and quality inspection. Details are as follows: 1. Material selection Based on the working conditions of the piston rod (e.g., load, environmental corrosion), medium-carbon steel (e.g., 45# steel), alloy structural steel (e.g., 40Cr, 35CrMo), or stainless steel (e.g., 304, 316) are prioritized. These materials must exhibit high strength, high toughness, and corrosion resistance. Non-destructive testing (e.g., ultrasonic inspection) is used to ensure the absence of internal defects such as cracks or inclusions. 2. Pre-treatment Forged blanks undergo annealing or normalizing to eliminate forging stress and improve machinability. For example: 45# steel: Normalizing (heated to 840–860°C, held, then air-cooled). 40Cr steel: Annealing (heated to 850°C, held, then furnace-cooled). 3. Quenching and tempering heat treatment Quenching: The piston rod is heated above its critical temperature (e.g., 840–860°C for 45# steel, 850°C for 40Cr steel), held for a specific duration, and rapidly cooled (e.g., oil or...

What Are The Uses Of High-precision Honing Tubes

2025-09-11

High precision honing tubes are widely used in industrial fields that require high reliability, long lifespan, and precise control due to their excellent dimensional accuracy, surface smoothness, and material properties. The following is a detailed classification of its main uses and specific application scenarios: 1、 Hydraulic and pneumatic systems: Core transmission components Hydraulic cylinder/cylinder barrel Application scenarios: Hydraulic cylinders or cylinders for construction machinery (excavators, loaders), industrial equipment (injection molding machines, die-casting machines), and agricultural machinery (tractors, harvesters). Advantage: The inner wall roughness Ra ≤ 0.4 μ m reduces seal wear and extends service life (such as the use of 27SiMn honing tubes for mining hydraulic support cylinders, which can achieve 300000 times of expansion and contraction without leakage). Straightness ≤ 0.25mm/m, ensuring smooth piston movement and avoiding jamming or leakage. high-pressure fuel pipe Application scenarios: hydraulic systems for construction machinery, ship servos, aerospace hydraulic devices. Advantages: High pressure resistance (up to 100MPa), corrosion resistance, and prevention of oil oxidation or particle wear caused by rough inner walls. Pneumatic control tube Ap...

Manufacturing Process Of Mechanical Hollow Shaft

2025-09-11

The manufacturing process of mechanical hollow shafts mainly includes forging process, cutting process, extrusion casting process, cross wedge rolling process, etc. The following is a detailed introduction: 1、 Forging process Forging is a common method for manufacturing hollow shafts, which causes plastic deformation of metal materials through pressure and thermal effects, forming hollow shafts with specific shapes and properties. The main steps of forging process include: Material preparation: Select suitable raw materials such as steel ingots, aluminum ingots, etc., and choose appropriate metal materials based on the required hollow shaft performance. Preheating: Heating the raw materials to an appropriate forging temperature to reduce internal stress in the metal and improve plasticity. Forging: Place the heated raw materials into forging equipment (such as forging hammers, presses, rolling mills, etc.), and use pressure to cause plastic deformation of the metal, forming the initial shape of a hollow shaft. Overhauling and elongation: By hammering, rolling, or rolling, the diameter of the hollow shaft is increased or its length is elongated to obtain the desired size. Forging: Forging the two ends of a hollow shaft to form a complete hollow shaft structure. Cooling and heat treatment: Dur...

Wear Resistance Of Precision Steel Shafts

2025-09-11

The wear resistance of precision steel shafts is a critical performance indicator that directly determines their service life, operational stability, and reliability in high-precision applications. Here is a detailed analysis of the factors, mechanisms, and enhancements related to their wear resistance: 1. Factors influencing wear resistance Material selection High-carbon chromium steel (e.g., SUJ2/GCr15): Widely used for its high hardenability and ability to achieve hardness up to HRC 60–62 after heat treatment. Stainless steel (e.g., SUS440C, SUS304): Offers corrosion resistance alongside moderate wear resistance (hardness up to HRC 58–60 for martensitic grades). Case-hardened steels (e.g., 20Cr, 20CrMnTi): Surface hardening via carburizing or nitriding creates a wear-resistant layer (≥ HRC 58) while maintaining a tough core. Surface Hardness Hardness is directly correlated with wear resistance. Precision steel shafts typically require a surface hardness of ≥ HRC 58 to resist abrasive wear. Techniques like induction hardening or chrome plating (900–1,200 HV) further enhance surface hardness. Surface finish A smooth surface (Ra ≤ 0.2 μm) reduces friction and minimizes adhesive wear. Precision grinding and polishing eliminate micro-asperities that could accel...

Core Structure Of The Hydraulic Oil Cylinder

2025-09-11

The core structure of a hydraulic oil cylinder can be divided into five main components. 1. Cylinder barrel Function: The cylinder barrel is the main body of the hydraulic oil cylinder. It forms the internal pressure chamber and bears the main working pressure. Characteristics: Typically made of high-strength seamless steel tubes. The inner bore surface requires precision machining, such as honing or rolling, to achieve high dimensional accuracy, geometric precision (e.g., straightness, roundness), and very low surface roughness. This ensures the reliability and service life of the sealing components. It must have sufficient strength and stiffness to withstand system pressure without bursting or excessive expansion. 2. Piston assembly Piston: Installed inside the cylinder barrel, it divides the internal space into two sealed chambers (rod side and blind side). It moves back and forth in a straight line under the push of hydraulic oil. The piston is equipped with piston seals (e.g., Glyd rings, Step seals, U-cups) to prevent leakage of pressure oil between the two chambers (internal leakage). Piston Rod: One end is connected to the piston, and the other end extends outside the cylinder barrel to connect to the load mechanism. It transmits the thrust force of the piston to the external...

What Are The Structural Components Of A Hydraulic Cylinder Body

2025-09-11

The structure of a hydraulic cylinder usually includes the following parts: Cylinder: The main body of a hydraulic cylinder, which is a hollow cylindrical structure used to accommodate pistons and hydraulic oil. Cylinder head: a component that seals one end of a cylinder, usually connected to the cylinder by bolts or welding, used to fix the piston rod and prevent hydraulic oil leakage. Piston: A component that performs reciprocating motion inside a cylinder, usually connected to a piston rod, converting hydraulic energy into mechanical energy. Piston rod: a component that connects the piston and external load, used to transmit force. Sealing device: including piston seal, piston rod seal, etc., used to prevent hydraulic oil leakage and external impurities from entering the hydraulic cylinder body. Buffer device and exhaust device: The buffer device is used to reduce the impact force when the piston reaches the end point and protect the hydraulic cylinder body; The exhaust device is used to eliminate the air inside the hydraulic cylinder body, ensuring the normal operation of the hydraulic system....

Characteristics Of Rolled Cylinder Tubes

2025-09-11

Rolled cylinder tubes are manufactured through a chipless cold-working process known as roller burnishing. This method uses high-pressure hardened rollers or balls to plastically deform the inner surface of the tube, resulting in significant improvements in performance and durability. The characteristics of rolled cylinder tubes can be categorized into advantages and limitations: 1. Key advantages Exceptional surface quality Ultra-low surface roughness: Achieves a mirror-like finish with surface roughness typically ranging from Ra 0.1 to 0.4 μm, and can reach as low as Ra 0.05 μm under optimal conditions. Smooth and uniform surface: Eliminates tool marks and micro-irregularities from pre-machining through plastic deformation, resulting in a consistent and smooth surface. Enhanced mechanical properties Surface hardening: Cold working induces strain hardening, increasing surface hardness by 15%–30%. Compressive residual stress: Introduces a layer of uniform compressive residual stress on the surface, significantly improving fatigue strength and resistance to stress corrosion cracking, thereby extending service life. Improved wear resistance: The combination of increased hardness and smooth surface reduces friction and enhances wear resistance. High dimensional and geometrical accu...