The heat treatment of copper rods primarily involves intermediate annealing and finished product annealing, with the annealing schedule being determined based on the alloy properties, product status, and performance requirements.
Currently, heat treatment for rod-shaped wire is widely performed using enclosures with specific atmospheres, such as box furnaces, roller hearth furnaces, and mesh belt furnaces. While employing protective atmospheres, the circulation of the atmosphere is enhanced to ensure uniformity and to guarantee a bright surface finish of the products.
In the heat treatment of bar materials, quenching and aging heat treatment are primarily used for alloys with age-hardening characteristics, enhancing the material's strength and overall properties. The quenching of extruded products is typically achieved through water seals at the extrusion outlet, while drawn products require a quenching furnace.
The precision finishing of copper alloy tube, rod, and wire materials mainly includes cutting ends (fixed length), straightening, and surface treatment. Depending on the specifications and requirements of the product, the cutting of ends can be done by either sawing or shearing methods. High precision is typically associated with larger-sized products, which are usually sawn. Straightness is a crucial quality indicator for tube and rod material products.
Common straightening machines for pipe and bar profiles include roller straighteners, pressure straighteners, sine wave straighteners, and tension straighteners. Among them, roller straighteners are the most widely used, as they achieve straightening by repeatedly bending the product through various roller shapes.
The pressure straightener is generally used for straightening large or extra-large diameter bars, shapes, and thick-walled pipes. Sinusoidal straightening primarily targets small diameter pipes and bars, achieving straightening through repeated bending over sinusoidal rollers.
The tension straightener clamps both ends of the product and applies a reverse tensile force, causing the product to undergo slight deformation for the purpose of straightening. It is mainly used for the straightening of special-shaped materials, with an elongation rate of 1-3%.
To ensure the finished product has a clean and shiny surface, surface treatment is required, which can be done either manually or automatically. Manual treatment involves operators wiping the surface of tube and bar materials to remove oil stains and dirt (including blowing cotton balls into the interior of the tubes with compressed air).
Automatic processing mainly involves cleaning pipes and rods by passing them through a liquid containing cleaning agents (including internal blowing), followed by drying and other treatments.
