Vacuum heat treatment furnace for copper alloys

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The vacuum heat treatment of copper alloy is mainly heating and vacuum annealing for different purposes. Only alloys of individual grades, such as bronze plating, can be vacuum quenched and vacuum tempered. Annealing for different purposes are: softening annealing, finished annealing and billet annealing.

Vacuum heat treatment furnace

The vacuum heat treatment equipment is mainly a vacuum heat treatment furnace. The following conditions should be considered when selecting a vacuum heat treatment furnace: that is, to meet the requirements of the vacuum heat treatment process to ensure quality and performance; to select a suitable heat source to meet the needs of production, the furnace has a simple structure, accurate temperature control, durability, and low investment; high degree of automation, production High efficiency, good working conditions and easy operation.

(1) Ordinary copper and copper alloy vacuum heat treatment furnace

Commonly used vacuum annealing furnaces for copper alloys: according to the structure, there are box furnaces, pit furnaces, walking furnaces, car hearth furnaces, stick hearth furnaces, chain water sealing furnaces, single hearth furnaces, double hearth furnaces, Bell furnace, etc. According to the production method, it is divided into: single batch vacuum annealing furnace, air cushion continuous vacuum annealing furnace, etc. According to the atmosphere in the furnace, there are annealing furnaces with or without protective atmosphere, annealing furnaces with protective atmosphere, etc. According to the heat source, there are coal furnaces, gas furnaces, heavy oil furnaces, resistance furnaces and induction furnaces. There are three types of quenching furnaces: vertical, horizontal and well.

(2) Commonly used copper alloy vacuum heat treatment furnace

At present, the main trends in the development of vacuum heat treatment furnaces: improve design, find new processes, and improve heat utilization efficiency; use low-temperature or high-temperature rapid annealing to reduce oxidation and dezincification; use protective gas annealing and forced circulation ventilation to make it rapidly heated , uniform temperature, improve the quality of annealed products; enhance the sealing effect, simplify the process and improve the level of integration and continuity.

The vacuum air cushion furnace is a commonly used vacuum annealing furnace for copper alloy single strips. There are online annealing and individual annealing. The current vacuum air cushion annealing furnace often combines pickling, water washing, drying, surface coating, passivation treatment, etc. Compared with the bell-type annealing furnace, it has high furnace temperature and short annealing time, and can achieve high-temperature rapid annealing. For example, for strips with a thickness of 0.05~1.5mm, only a few seconds of heating time is required, and for thick strips, only one heating time is required. minutes. The heating speed is adjustable, the heating is uniform, the annealed surface quality is good, and the structure and properties are uniform.

The ratio of the maximum thickness to the minimum thickness of the vacuum air-cushion furnace annealed strip is 10:15, the ratio of the maximum width to the minimum width is 2, and the ratio of the thickness to the width of the same strip is less than 1/250. At present, the annealing of strips with a thickness of 0.05~1.5mm and a width of 250~1100mm can be achieved. The annealing speed is (4~100)m/min, the production capacity is 5t/h, and the thermal efficiency is 85%. The heat source can be heated by electricity or gas.

The air-cushion furnace is composed of uncoiling, welding, degreasing, furnace, pickling, shearing, coiling and mixing, control spoke, looper tower, etc.

Vacuum air cushion annealing furnace is a new technology of continuous vacuum heat treatment. When the strip passes through the furnace, the upper and lower surfaces are held up and suspended in the vacuum heat treatment furnace by a uniform jet of high-temperature air. For continuous annealing, two sets of uncoilers and two sets of coilers are provided. In order to improve the surface quality of the strip and remove the rolling oil or emulsion on the surface of the strip, the strip enters the vacuum annealing furnace to be degreased, washed and dried. When annealing pure copper or bronze strip, the surface of the strip will not be oxidized or pickled, and the heating zone and cooling zone should be filled with 2%~5%H2, containing 95%~98%N2 Protective gas. When annealing brass strip, the heating zone and cooling zone are not filled with protective gas, but need to be pickled, washed and dried. For some special-purpose copper alloys, coating and drying are carried out after annealing. In order to prevent the strip from deviating, a photoelectric centering device and a deviation correction wheel are installed at the nozzles in the upper and lower rows of the heating zone and the cooling zone, and the edge irregularity rate after the strip is coiled is less than ±1mm. Some air-cushion continuous annealing furnaces also have tension leveling devices. The use of air-cushion continuous furnace greatly improves the surface quality and the uniformity of product structure and performance.

Equipment selection: RVA series vacuum heat treatment furnaces produced by SIMUWU are high-quality products for vacuum heat treatment of tooling and moulds. Good temperature control accuracy and temperature control uniformity ensure the effective progress of the vacuum heat treatment process. SIMUWU specializes in the manufacture of vacuum furnaces, has more than ten years of relevant experience, and has a good reputation in the field of vacuum furnace manufacturing. The product line includes vacuum air quenching furnace, vacuum oil quenching furnace, vacuum tempering furnace, etc., which are widely sold in developed and developing countries.