Phase 1: Precision Machining and Preprocessing of Components
1.High precision cutting
The first step in production is to cut the steel plate on a laser cutting table. Modern manufacturing processes use high-power lasers for precise cutting of wear-resistant steel plates, ensuring the accuracy of the external dimensions of the parts, and cutting errors are usually controlled within a very small range.
2.Stress relief treatment
After cutting and cutting, there is cutting stress inside the parts. In order to prevent deformation during subsequent processing, key components such as the support and connecting rod of the vibration mechanism need to be subjected to stress relief annealing in a heat treatment furnace. This process can eliminate over 90% of cutting stress and significantly improve the dimensional stability of the parts during subsequent processing.
3. Key component heat treatment
For components directly subjected to wear and impact (such as the base plate, rammer, and pressure beam), hardening treatment is essential. High-end manufacturers employ high-frequency quenching technology to uniformly harden the rammer and pressure beam to a specified depth (e.g., 5mm), which not only enhances surface wear resistance but also ensures the uniformity of the hardened layer, thereby extending the service life of the screed under harsh working conditions.
Phase 2: Manufacturing of Box Structure and Core Mechanism
1.Frame welding and robot welding
The main body of the ironing board is a box frame structure, and its welding quality directly affects the overall rigidity. In order to ensure the continuity and high quality of welds, the manufacturing workshop uses welding robots for automated welding. By optimizing welding process parameters and sequences, and using specialized welding fixtures, welding deformation can be effectively controlled.
2. High precision machining
The welded frame needs to be precision machined, especially the bottom surface in contact with the wear-resistant base plate, whose flatness directly affects the paving quality. During processing, a CNC machining center is used to reduce deformation caused by clamping force through optimized clamping methods, and key parts are milled to ensure that flatness errors are controlled within a very small range (such as within 0.2 millimeters).
3. Vibration mechanism processing
The dual vibration mechanism is the core of achieving high pre compaction of the ironing board. The process is crucial when processing irregular sheet metal parts such as supports and connecting rods. In order to ensure the positional tolerance between the inner hole and the end face (which is the core to prevent eccentric shaft jamming), the principle of “uniform reference” is usually adopted: first precision machining the inner hole, then machining the end face based on the inner hole, and finally using a special fixture for simulated assembly inspection to ensure a one-time assembly pass rate.
Phase 3: Expansion mechanism and precision assembly
1. Expansion sleeve and guide rail processing
For the telescopic ironing board, the machining accuracy of the telescopic sleeve is extremely high. The inner surface of the expansion sleeve needs to be precision machined, and its surface roughness is even 20 times smaller than the diameter of a human hair, to ensure that the left and right expansion ironing plates can smoothly and stably expand and contract, thereby flexibly adjusting the paving width.
2. Final assembly and debugging
Assemble the processed box body, vibration mechanism, expansion mechanism, hydraulic pipeline, and electrical circuit. At this stage, it is also necessary to fix the wear-resistant bottom plate to the bottom surface of the ironing plate frame with high-strength bolts.
Stage 4: Functional testing and final quality inspection
1. Electric heating system testing
Due to the need to heat the screed bottom plate to above 130 ℃ during asphalt paving, a comprehensive test of the heating system must be conducted. Modern ironing boards often use electric heating systems. After being powered on, check whether the heating rod is working properly, whether it can achieve fully automatic constant temperature control, and ensure uniform heating of the bottom plate.
2. Whole machine function inspection
After assembly, experienced technicians will conduct a series of functional tests on the ironing board, including:
- Action test: Check whether the telescopic oil cylinder and arch adjustment mechanism operate smoothly.
- Compaction system testing: Start the vibration and vibration mechanism, check whether the hammer stroke (such as hydraulic adjustment range of 2mm-8mm) and frequency meet the standards.
- Sealing test: Conduct a pressure test on the hydraulic system to check for leaks.
3. Simulated working condition inspection
Finally, use inspection connection fixtures to simulate assembly and verify the fitting accuracy between each component. All measurement data are recorded in the final inspection report to ensure that the factory products fully meet the design requirements.