Galvanized spring steel wire machine
Galvanized spring steel wire: generally hot-dip galvanized or electroplated according to the finished size, or pickled by wire, hot-dip and then cold-drawn to the specified size.
Drawing spring steel wire process: (steel) drawing-surface treatment-drawing (can be used for wire arrangement) Lead quenching spring steel wire: lead bath quenching in wire size or cold drawing intermediate specifications, then surface treatment and drawing.
Oil quenching spring steel wire: carbon steel or alloy steel can be selected according to needs, cold drawn to finished size after surface treatment, and then tempered. This process is mainly used for automobile suspension springs and valve spring steel wires. Of course, it can also be used.
Surface treatment: Pickling and phosphating are generally used to remove iron oxide scale and form a phosphating film. Some people also use mechanical methods. The purpose is to meet the requirements of the cold drawing process and obtain a smooth surface. For spring wires that require high fatigue life, such as valve spring wires, they should be peeled off to reduce surface defects. If the steel mill can repair the billet, it will also help reduce defects.
Wire drawing: The finished product drawing process has a great influence on the product performance. Generally speaking, in order to ensure the toughness of the product, the total reduction rate (area reduction rate) is relatively large, about 90%, and the hole type reduction rate is relatively small, about 10%-20%. For high-strength spring steel wire, the outlet temperature of each steel wire should be controlled below 150℃ to prevent the steel wire from being twisted and deformed due to strain aging. Strain aging is the main defect that causes the steel wire to be scrapped. Therefore, good lubrication and sufficient cooling are necessary during the drawing process. Smaller pass-through rate and drawing speed help reduce the temperature rise of the steel wire.
Heat treatment: Carbon steel spring wire is usually quenched in a lead bath to obtain a very fine pearlite structure (soxite), which is beneficial to improve the drawing properties and spring performance. The alternative process of the lead bath is not yet fluidized, only in some small diameter applications. Alloy steel wire is generally annealed and heat treated to adapt its structure to drawing deformation. The heat treatment of stainless steel wire is solid solution, with the purpose of improving the structure to meet the needs of wire drawing. The finished wire is oil quenched. The wire is heated to austenitizing temperature for a period of time by induction heating or gas or oil heating furnace. After quenching, it is tempered at a moderate temperature. Although nominally called oil quenching, it is basically water quenching or water quenching and polymer materials.
