Commonly used materials for pump shafts

Thread Content

There are many materials for multi-stage pump shafts, such as: 45#, 40Cr, 42CrMo, 2Cr13, 17-4PH, 2507, etc. The selection of multi-stage pump shaft material is generally based on the working conditions of the water pump. If it is clean water, then we can choose conventional 45# steel material to meet the user's requirements. Multi-stage pump shaft material 45# steel characteristics: 45# is the grade of steel. It is a high-quality carbon structural steel, corresponding to the Japanese standard S45C and the American standard.: 1045, German standard C45. It is characterized by higher strength and deformation resistance than ordinary A3 steel. 45# steel is widely used in machinery. When not heat treated: HB≤229 ； heat treatment: Normalizing ； impact energy: Aku≥39J ； The strength is high, the plasticity and toughness are good. After quenching and before tempering, the 45# steel plate is qualified if the hardness is greater than HRC55 (up to HRC62). After heat treatment and tempering, it can reach HRC42-46, which can ensure that it is more durable. It has good mechanical properties and can obtain the surface hardness requirements. It is used to make small-section quenched and tempered parts that can withstand large loads and large normalized parts with small stress, as well as surface-hardened parts that do not require high core strength, such as shafts, pins, guide posts, watch hands and other components. If the user has requirements for material impact resistance, then we can choose 40Cr. Multi-stage pump shaft material 440Cr material properties: 40Cr is the standard steel grade of my country's GB. 40Cr steel is one of the most widely used steels in the machinery manufacturing industry. After quenching and tempering treatment, it has better comprehensive mechanical properties, better low-temperature impact toughness and low notch sensitivity. The steel has good hardenability and is suitable for making medium-sized plastic molds. The hardness of 40Cr after tempering is about 32-36HRC, which means about 301-340HB. Medium carbon quenched and tempered steel, cold heading mold steel. The steel is moderately priced and easy to process. It can obtain certain toughness, plasticity and wear resistance after appropriate heat treatment. Normalizing can promote tissue refinement, and then * * Balanced state can improve the cutting performance of the blank. Tempered at a temperature of 550~570℃, the steel has better comprehensive mechanical properties. The hardenability of this steel is higher than that of 45# steel, and it is suitable for surface hardening treatments such as high-frequency quenching and flame quenching. Multi-stage pump shaft material 440Cr material use: After quenching and tempering, this kind of steel is used to manufacture mechanical parts that bear medium loads and work at medium speeds, such as steering knuckles, rear half shafts of automobiles, and gears, shafts, worms, spline shafts, center sleeves, etc. on machine tools. ； After quenching and medium temperature tempering, it is used to manufacture parts that withstand high load, impact and medium speed operation, such as gears, spindles, oil pump rotors, sliders, collars, etc. ； After quenching and low-temperature tempering, it is used to manufacture parts that bear heavy load, low impact and have wear resistance, and the physical thickness of the cross-section is less than 25mm, such as worms, spindles, shafts, collars, etc. ； After quenching and tempering and high-frequency surface quenching, it is used to manufacture parts with high surface hardness and wear resistance without great impact, such as gears, sleeves, shafts, spindles, crankshafts, spindles, pins, connecting rods, screws, nuts, intake valves, etc. In addition, this kind of steel is suitable for manufacturing various transmission parts that undergo carbonitriding treatment, such as gears and shafts with larger diameters and good low-temperature toughness. Multi-stage pump shaft material 40Cr shaft parts: Shaft parts are one of the typical parts often encountered in machines. It is mainly used to support transmission components, transmit torque and bear load. Shaft parts are rotating parts whose length is greater than the diameter. They are generally composed of the outer cylindrical surface, conical surface, inner hole and thread of the concentric shaft and the corresponding end surface. According to different structural shapes, shaft parts can be divided into smooth shafts, stepped shafts, hollow shafts and crankshafts. The difference between 45# steel and 40Cr and 42CrMo: 45# steel is high-quality carbon structural steel with a carbon content of 0.42--0.50%, a tensile strength of 610MPa, and a yield point of 360MPa. ； Used for general shaft parts. 40Cr is alloy structural steel with a carbon content of 0.37--0.45%, a chromium content of 0.8--1.1%, a tensile strength of 1000MPa, and a yield point of 800MPa. ； Used for force-bearing shafts with large loads. 42CrMo is an alloy structural steel with a carbon content of 0.38--0.45%, a chromium content of 0.9--1.2%, a molybdenum content of 0.15--0.25%, a tensile strength of 1100MPa, and a yield point of 950MPa. Use components with heavy loads and high reliability requirements. For generally corrosive materials, you can choose 2Cr13. The characteristics of this material are as follows:: 2Cr13 is a martensitic stainless steel, which is magnetic and has good hardness. It needs to be preheated for welding. Austenitic stainless steel electrodes used for welding with Q235 do not need to be preheated, such as A302 and A307. Control the dilution rate of the weld seam during welding, do not swing welding, and use a smaller current. Applicable range of 2Cr13 stainless steel materials: 2Cr13 stainless steel has high hardness and good corrosion resistance in the quenched state. Many are used to make knives, which are "cutting edge" martensitic steels. They are also used in surgical knives, similar to earlier stainless steels such as Brinell high chromium steel. They are also used in steam turbine blades, etc., with a wide range of applications. Mechanical properties of 2Cr13 stainless steel material: Tensile strength σb (MPa): Quenching and tempering, ≥635 ； Conditional yield strength σ0.2 (MPa): Quenching and tempering, ≥440 ； Elongation δ5 (%): Quenching and tempering, ≥20 ； Area reduction ψ (%): Quenching and tempering, ≥50 ； Impact power Aku2(J): Quenching and tempering, ≥63 ； hardness : Annealing, ≤223HB; Quenching and tempering, >192HB ； Heat treatment specifications and metallographic structure of 2Cr13 stainless steel: Heat treatment specifications: 1) Annealing, slow cooling at 800~900℃ or rapid cooling at about 750℃ ； 2)Quenching, oil cooling at 920~980℃ ； 3) Tempering, rapid cooling at 600~750℃. Metallographic organization: The tissue is characterized by martensitic type. Based on the overview of the above and so on, there is no better material for shafts. You can only choose the more suitable material according to the working conditions.