Views: 0 Author: Site Editor Publish Time: 2025-09-28 Origin: Site
Related Parts: Brake hard pipes (carbon steel/stainless steel), brake hose connectors, and ABS system oil pipes.
Key Forming Processes:
Flaring + Chamfering: The end of the hard pipe is flared into a standard 45° bell mouth (compatible with double union nuts), while chamfering removes burrs to avoid damaging seals during assembly. The precision requirement is ±0.05mm to ensure gap-free fitting with connectors and prevent brake fluid leakage.
Necking + Knurling: The connection end of the hose connector is necked to a matching diameter, and the outer surface is knurled to increase friction. A crimping process is used to achieve a secure connection and prevent detachment under high pressure.
Equipment Requirements: Fully automatic hydraulic pipe end forming machines are predominantly used, equipped with pressure sensors and visual inspection systems to real-time monitor forming pressure and bell mouth dimensions, with automatic rejection of unqualified products.
Related Parts: Fuel supply pipes, return pipes, evaporation pipes (mostly stainless steel or galvanized steel pipes), and fuel filter connectors.
Key Forming Processes:
Stepped Necking: The pipe end is necked into multi-stage stepped structures of different diameters to match the stepped interfaces of fuel pumps and filters, achieving dual protection through "interference fit + seal ring sealing".
Internal Thread Forming: Some connector ends require internal threading, using an integrated "flaring followed by tapping" process to avoid precision deviations caused by secondary clamping.
Technical Features: After forming, phosphating or galvanizing treatment is required, and the inner wall roughness of the pipe end must be ≤ Ra1.6μm to prevent impurity accumulation from clogging fuel injectors.
Related Parts: Exhaust manifold branches, middle-section exhaust pipes, and muffler connection pipes (mostly ferritic stainless steel or aluminized coated steel pipes).
Key Forming Processes:
Flanging + Corrugation Forming: The butt end of the exhaust pipe is flanged to increase the welding contact area (enhancing welding strength). Flexible sections adopt "flaring + corrugation forming" to absorb engine vibration through wave-shaped pipe ends and reduce exhaust noise.
Tapered Necking: The inlet pipe end of the muffler is necked into a taper, inserted into the main exhaust pipe, and welded to improve exhaust gas flow guidance.
Equipment Requirements: High-temperature resistant dies (e.g., tungsten steel) are required. The roundness error of the formed pipe end must be ≤ 0.2mm to avoid misalignment during welding.
Related Parts: Radiator inlet/outlet pipes, water pump connection pipes, and heater core pipelines (mostly aluminum or copper pipes).
Key Forming Processes:
Flaring + O-Ring Groove Forming: After flaring the aluminum pipe end, an annular O-ring groove is machined at the root of the flare. During assembly, the O-ring achieves "static sealing", replacing traditional gasket sealing and reducing assembly complexity.
Straight Necking: When small-diameter pipes are butted, one end is necked to match the inner diameter of the other, using "insert welding" to reduce fluid resistance.
Advantages: No wrinkles at the formed pipe end, smooth inner wall, and coolant flow loss ≤ 5%, improving heat dissipation efficiency.
Steering System: Power steering oil pipe ends adopt "flaring + ferrule groove forming" to match ferrule-type connectors, ensuring stable transmission of steering assist oil.
Air Conditioning System: Air conditioning refrigerant pipelines (mainly copper pipes) use "flaring + cup flaring" processes, secured with nuts to prevent leakage of R134a or R1234yf refrigerants.
Structural Components: Steel pipe ends of seat slides and chassis brackets are formed by "necking + sealing" to enhance structural support strength and prevent internal corrosion.
Thin-walled copper pipes (thickness 0.3-0.8mm): Adopt "flexible clamping + low-pressure forming" to avoid wall wrinkling;
High-strength stainless steel pipes (tensile strength ≥ 500MPa): Equipped with hydraulic boosting systems (pressure ≥ 50MPa) to ensure sufficient plastic deformation;
Aluminum alloy pipes (easily oxidized): Forming dies must be coated with Teflon to reduce friction damage.
Enhanced Connection Reliability: Replacing the traditional "welding + grinding" process, cold forming preserves the metal grain structure of the pipe, increasing pipe end strength by 15-20% and reducing failures caused by connection failure (e.g., brake failure, fuel leakage).
Reduced Production Costs: Automated forming reduces manual operations, increasing material utilization from 70% (traditional processes) to over 95%. A single production line saves hundreds of thousands of yuan in material costs annually.
Adaptation to Modular Production: Standardized pipe end forming supports modular procurement of automotive parts (e.g., brake pipeline assemblies), shortening the vehicle assembly cycle.
Intelligent Upgrading: Integrating AI visual inspection systems to automatically identify pipe surface defects (e.g., scratches, uneven wall thickness) and adjust forming parameters; enabling remote equipment maintenance via industrial internet.
Lightweight Adaptation: Addressing the lightweight needs of new energy vehicles, machines are upgraded for "high-precision forming of thin-walled aluminum pipes", capable of processing aluminum pipes with thickness below 0.2mm without springback after forming.
Multi-Process Integration: Developing integrated "forming-cleaning-flaw detection" equipment. After pipe end forming, ultrasonic flaw detection and high-pressure cleaning are performed directly to meet the "zero-impurity" pipeline requirements of new energy vehicles.
Processed pipes: Φ10×1.0mm galvanized steel pipes; Batch: 5 million pieces/year;
Forming processes: 45° bell mouth (tolerance ±0.03mm) + end chamfering (R0.5mm);
Equipment configuration: Dual-station dies, forming beat of 15 pieces/minute, equipped with online laser diameter gauges and automatic sorting of unqualified products;
Results: Product pass rate increased from 98% to 99.8%, processing cost per piece reduced by 0.12 yuan, and annual cost savings of 600,000 yuan.
