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Technical Requirements Overview

In manufacturing, the technical requirements for parts are crucial to ensuring product quality and performance. These requirements cover a wide range of processes—from surface treatments to heat treatments—and each step directly influences the final quality of the parts. Next, we’ll delve deeper into these technical requirements and reveal the secrets behind part manufacturing.

▣ General Technical Specifications
In manufacturing, the technical requirements for parts are crucial to ensuring product quality and performance. These requirements cover multiple stages—from surface treatment to heat treatment—and each stage directly affects the final quality of the parts.

▣ Requirements for Surface Treatment of Machined Parts
In the parts manufacturing process, surface treatment is a critically important step. It involves removing oxide scale from the workpiece, ensuring that the part’s surface is free of defects such as scratches and abrasions, and also eliminating burrs and flash to round off sharp edges. Furthermore, there are specific standard requirements for chamfers and relief grooves that are not explicitly indicated: chamfers should be 0.5 × 45°, and relief grooves should measure 1.2 × 0.3. Ultimately, the surface of the finished part must be smooth and burr-free to meet the product’s quality and performance specifications.

▣ Technical Requirements for Unspecified Tolerances
In the manufacturing process of metal parts, the technical requirements concerning unspecified tolerances cover various aspects such as dimensions, shape, orientation, and surface roughness of the parts, with the aim of ensuring the manufacturing accuracy and quality of the parts. By strictly adhering to these technical requirements, the performance of the parts can be further optimized to meet the overall design needs of the product.

▣ Limit deviations for dimensions without specified tolerances
In the manufacturing of metal parts, the limit deviations for dimensions without specified tolerances shall comply with the GB/T 1804-m standard; while geometric tolerances not explicitly indicated shall be governed by GB/T 1184-K. Furthermore, for length dimensions that are not explicitly specified, the allowable deviation is ±0.5. Compliance with these standards is crucial for ensuring the manufacturing accuracy and quality of metal parts.

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Surface and Heat Treatment Technologies

▣ Surface Treatment Technical Requirements
In the manufacturing process of metal parts, surface treatment technology is an indispensable step. Surface treatment not only affects the aesthetic quality of the parts but also has a profound impact on their service life and performance. Therefore, it is essential to strictly adhere to the relevant technical standards to ensure that every step of the surface treatment achieves the desired results.

▣ Detailed Explanation of Surface Treatment Technologies
There are numerous surface treatment technologies available for metal parts, each with its own specific applications and effects. For example, white (or black) zinc plating provides corrosion protection for parts, while paint (or powder coating) application endows them with a wide variety of colorful appearances. In addition, there are other treatments such as blackening, electrophoretic coating, and chrome plating—all of which play unique roles and together form a rich and diverse system of surface treatments for metal parts. Moreover, to meet specific process requirements—such as enhancing friction or providing aesthetically pleasing textures—surface knurling and straight-line (mesh) patterns are also employed; these treatments adhere to the standards specified in GB/T 6403.3. The comprehensive application of these technologies significantly enhances both the performance and service life of metal parts.

▣ Key points of heat treatment technology
Heat treatment technology is a critical step in the manufacturing process of metal parts. Through processes such as heating, holding at temperature, and cooling, it alters the internal microstructure of metallic materials, thereby enhancing their mechanical properties and service life. Different heat treatment processes yield different effects: for instance, quenching can significantly improve the hardness and wear resistance of metals, while tempering helps maintain their toughness to a certain extent. When carrying out heat treatment, it is essential to strictly adhere to relevant standards and technical requirements to ensure that the metal parts meet the intended performance specifications.

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Technical Requirements for Specific Parts

▣ Casting Technical Requirements
In the manufacturing of metal parts, casting technology is equally indispensable. It involves multiple stages, including casting design, manufacturing, and post-processing, all aimed at ensuring that castings possess the required physical properties and dimensional accuracy. The quality of castings directly affects the overall performance and service life of the final product; therefore, strict adherence to casting technology specifications is particularly important.

▣ Detailed Technical Requirements for Die Castings
In the manufacturing of metal parts, die casting technology plays a crucial role. It encompasses a series of technical specifications, including dimensional tolerances, geometric tolerances, chamfers, wall thickness, rib thickness, transition fillets, and draft angles, all aimed at ensuring that castings exhibit excellent physical properties and dimensional accuracy. Moreover, the quality of the castings is subject to stringent monitoring; they must be full and smooth, free from any defects such as porosity, shrinkage cavities, cracks, inclusions, or material shortages. At the same time, the indentation left by the ejector pins during demolding must also be kept within a specified depth to guarantee the integrity of the casting surface. The entire manufacturing process must strictly adhere to the GB/T 15114 standard "Aluminum Alloy Die Castings," and after surface treatment, the castings must undergo necessary machining and be coated with protective oils.

▣ Sand Casting Technical Requirements
In the sand casting process, a series of strict technical specifications must be followed. First, for any casting fillets not explicitly specified, they should be kept within the range of R5 to 10. Second, after completion, the castings must undergo thorough sand removal to ensure that risers and gates are completely cleared and the surfaces are smooth and even. In addition, the castings need to undergo artificial aging treatment to enhance their physical properties. Regarding quality, the castings must be entirely free from defects such as sand holes, porosity, shrinkage cavities, or cracks.

▣ Stamping Part Technical Specifications
In the production process of stamped parts, strict inspections must be carried out before stamping to ensure that their dimensional accuracy and surface quality meet the standards. Secondly, during the stamping process, process parameters such as stamping force and stamping speed must be strictly controlled to guarantee the forming quality and precision of the stamped parts. In addition, for castings after stamping, meticulous surface treatments are also required to enhance their aesthetic quality.

▣ Technical Requirements for Plastic Parts
In the production and inspection processes of plastic parts, a series of stringent technical standards must be followed. These standards not only affect the dimensional accuracy of the products but also play a crucial role in determining their performance and durability. Regarding dimensions, plastic parts must strictly adhere to the GB/T 15055-m standard. Unless otherwise specified, this standard should be applied by default to ensure the dimensional accuracy of the products.

▣ Technical Requirements for Welded Components
The technical requirements for welded components encompass several aspects. First, for linear and angular dimensions without specified tolerances, the limit deviations shall comply with the GB/T 19804 Class B standard. Second, the quality of the weld seam is of paramount importance; it should exhibit a uniform and smooth appearance, and any slag must be thoroughly removed.

▣ Technical Requirements for Various Parts and Components
During the welding process, various parts and components also have their own specific technical standards. These standards cover multiple aspects, including dimensions, shape, positioning, and material, with the aim of ensuring that each welded component meets the predetermined quality requirements.