The core principles for Welded B-Type Tubes for Heater Cores are to avoid weld damage throughout the process, strictly control processing and assembly stress, standardize working condition protection, cover the entire process of incoming material control, processing and forming, brazing assembly, system use, maintenance and repair, focus on the two weak links of welds and cavity thin walls, prevent leakage, cracking and other failure problems, and ensure product service life and operational stability.
1、 General requirements for core control
With "protecting the integrity of the weld seam and maintaining the stability of the cavity structure" as the core, all operations follow the principles of "no impact, no forced installation, temperature and pressure control, and corrosion prevention", eliminating rough operations, illegal processing, and improper use of working conditions, and avoiding hidden damage and later failure from the source.
2、 Key control directions throughout the entire process
1. Incoming material and warehouse control: Strictly control the quality of incoming materials, inspect weld seams and cavity defects; Standardize storage and protection to prevent collision, oxidation, and impurities from entering. During cutting, do a good job of deburring to prevent unqualified products from being put into use.
2. Processing and molding control: Special tooling equipment is used to standardize bending and cutting processes, avoid stress on welds, prohibit hammering correction, and prevent thinning, wrinkling, and micro cracks in welds.
3. Brazing assembly control: Do a good job of degreasing and degreasing before welding, accurately control the brazing temperature, insulation duration, and assembly gap, and avoid overburning, virtual welding, and assembly stress; Standardize pressure testing and leak detection after brazing, with a focus on inspecting the weld seam and brazing seam position.
4. System usage control: standardize assembly operations, avoid excessive tightening and forced pulling; Choose a coolant suitable for aluminum alloy, exhaust the system properly, and prevent electrochemical corrosion, cavitation, and thermal shock.
5. Maintenance and inspection control: Regularly flush the system, check the working conditions, and avoid the accumulation of impurities and the mixing of oil; Priority should be given to replacing pipes upon discovering leaks, and repeated local welding is prohibited to delay fatigue damage.
3、 Core taboos
It is strictly prohibited for welds to bear bending, compression, and impact loads; Rough assembly, overpressure testing, and forced calibration are strictly prohibited; It is strictly prohibited to use inferior coolant or mix different specifications of coolant; Long term operation under high temperature, cavitation, and impurity accumulation conditions is strictly prohibited.
