manufacturing process 1. Material Selection & Inspection Material: High-grade alloy spring steels are used, such as 50CrV (Chromium-Vanadium steel) or 65Mn (Manganese steel). 50CrV is preferred for high-end blades due to its superior toughness and fatigue resistance. ...
Material: High-grade alloy spring steels are used, such as 50CrV (Chromium-Vanadium steel) or 65Mn (Manganese steel). 50CrV is preferred for high-end blades due to its superior toughness and fatigue resistance.Inspection: The raw steel is inspected for chemical composition consistency and internal defects (like inclusions or voids) using ultrasonic testing.
2. Blanking (Cutting the Profile)
Method: High-power Laser Cutting is the standard method for its precision and minimal heat-affected zone.Process: The large steel sheet or coil is cut into a circular blank, slightly larger than the final diameter of the blade body.
3. Rough Machining
Process: The blank undergoes rough turning on a lathe to machine the inner diameter (arbor hole) and outer diameter, leaving a small amount of material for final precision machining later.
This is the most critical phase, defining the mechanical properties of the blade body.A. QuenchingPurpose: To increase the hardness and strength of the steel.Process: The blade is heated in a controlled-atmosphere furnace to its austenitizing temperature (approximately 830-860°C or 1525-1580°F) and then rapidly cooled (in oil or a polymer quenchant), transforming its microstructure to martensite.B. TemperingPurpose: To relieve the immense internal stresses and brittleness caused by quenching. This crucial step restores toughness and elasticity to the blade.Process: The blade is reheated to a lower temperature (e.g., 400-500°C / 750-930°F), held, and then slowly cooled. Precise control here achieves the ideal balance of strength and flexibility.C. Tensioning (Stress Leveling / Roller Tensioning)Purpose: This is a hallmark of premium blade manufacturing. Specialized rollers apply pressure to specific areas of the blade, creating a controlled, uniform tensile stress field within the body.Why it's vital:Counters Centrifugal Force: At high speeds, centrifugal force tries to expand the blade. The pre-set tension counteracts this, maintaining stability and flatness.Counters Thermal Expansion: Cutting generates heat. The tension compensates for thermal expansion, preventing the blade from warping or "wandering," thus ensuring straight cuts.Improves Fatigue Life: It homogenizes residual stresses, significantly enhancing the blade's resistance to failure from repeated stress cycles.
After heat treatment, the blade warps. These steps restore its geometric perfection.A. Surface Grinding (Double-Disc Grinding)Process: The blade is passed through a large double-disc grinder to grind both faces simultaneously.Goal: To achieve exceptional flatness and parallelism, and to establish the final precise thickness.B. Fine Machining of Bore and ODProcess: The arbor hole and outer diameter are finish-machined on a precision CNC lathe to achieve tight tolerances and a smooth surface finish. The accuracy of the arbor hole is critical for proper mounting and minimal runout.
6. Slotting and Drilling
Milling Anti-Vibration / Expansion Slots: Slots are milled into the blade body. These slots dampen noise and vibration during cutting and, more importantly, act as stress-relief points to prevent distortion from heat buildup.
Drilling Positioning Holes: Holes and slots are machined to precisely locate and seat the carbide tips in the subsequent brazing process.
7. Cleaning & Surface Protection
Cleaning: The blade is thoroughly cleaned to remove oil, coolant, and metallic dust.
Surface Treatment: A protective coating is applied, typically Bluing or Phosphating, to form a rust-resistant layer and prevent corrosion during storage and use.
