The cold drawing of aluminum and aluminum alloy hot extruded tubes GB 4437-84
Introduction:
Aluminum and its alloys are the most common materials used in aircraft and aerospace components. In order to utilize this material properly, it is necessary to understand the properties and characteristics of its various forms. One of the most common processes for forming aluminum is called hot extrusion. This is a process in which a solid piece of aluminum is heated and then pushed through a die to form a desired shape. In order to make aluminum components with tight tolerances and precise dimensions, it is necessary to follow certain guidelines and standards. The Chinese standard GB 4437-84 provides guidance on the cold drawing of aluminum and its alloys after hot extrusion. Below, we will discuss the important points of the standard and how it relates to cold drawing aluminum.
Scope of the standard:
The GB 4437-84 standard covers the cold drawing of aluminum and aluminum alloy hot extruded tubes. This standard is applicable to all aluminum and aluminum alloys that are hot-extruded and then cold drawn in order to obtain the desired size, shape and dimension. The purpose of this standard is to ensure that all aluminum and aluminum alloy tubes that are cold-drawn from hot-extruded stock possess the desired characteristics and meet the requirements for both cold drawing and extrusion.
Requirements for hot-extruded tubes:
The GB 4437-84 standard lays down specific requirements for the hot-extruded tubes that are to be cold-drawn. For instance, the tubes must be heated evenly and consistently to a temperature that is suitable for cold drawing. The temperature must be in accordance with the American Society for Testing Materials (ASTM) standard in order to avoid extrusion burns and other damage to the tubes. The tubes must also be formed and drawn to the specified shape and size using the appropriate dies and tools. The metal must have the proper lubrication, and must be drawn in a uniform and consistent manner.
Requirements for cold drawing:
The standard also specifies requirements for the cold drawing of the hot-extruded tubes. It mandates that the cold drawing operation be performed in such a way that the surfaces of the tubes are not damaged and the dimensions remain within the tolerances specified in the standard. Further, the components must be drawn in a steady, even manner over the length of the entire tube without producing any burrs or sharp edges. The speed at which the tube is drawn must also be appropriate, and the operator must be skillful in order to produce a smooth finish on the drawn tube.
Conclusion:
The Chinese standard GB 4437-84 is an important reference document for the production of aluminum and aluminum alloy tubes. It provides guidance on the cold drawing of these materials after hot extrusion, and outlines the specific requirements and regulations that must be adhered to in order to produce an appropriate and safe product. By following the guidelines and specifications laid out in the GB 4437-84, manufacturers are able to ensure that their aluminum and aluminum alloy tubes meet the desired criteria and provide a safe and secure product for use in aircraft and aerospace components.
