Custom Slitting Service & Process Details for Bright Surface Galvanized Steel Coil

I. Core Custom Slitting Services for Bright Surface Galvanized Steel Coil

1. Precise Dimensional Customization

• Slitting width: Customizable width from 50mm to 1500mm (the minimum narrow strip can be 30mm according to equipment precision), with the width tolerance accurately controlled within ±0.1mm, meeting the fine processing needs of precision stamping, narrow strip bending, etc.;
• Coil diameter customization: The inner hole is adaptable to industry universal inner diameters such as 508mm and 610mm, and the outer coil diameter is customized according to customers' storage and feeding equipment requirements, balancing the convenience of on-machine operation and storage efficiency;
• Fixed-length cutting: Fixed-length shearing can be completed with slitting to customize the length of single sheet, adapting to customer scenarios without coil processing.

2. Customized Process Adaptation

• Scratch-free customization: For bright surface coils used in home appliance panels and decoration, we adopt the soft contact slitting process with scratch-proof rubber rollers and mark-free material guiding devices to ensure the surface finish of the coil is consistent with the original after slitting, without scratches or indentations;
• Zinc coating protection customization: For products requiring subsequent stamping and bending, we adjust the slitting tension and shearing gap to avoid cracking and falling off of the zinc coating, ensuring the forming performance of the coil after slitting;
• Burr control customization: For customers engaged in precision hardware processing, we provide high-precision burr-free slitting with smooth and flat shearing surface and burr height ≤0.05mm, which can be directly put into on-machine processing without secondary grinding by customers.

3. Customized Packaging

• Inner packaging: Full wrapping with PE protective film (adhesion can be customized into high, medium and low grades), with hard paper corner protectors installed at the edges to avoid edge warping and scratching of the coil after slitting;
• Outer packaging: Packing with waterproof coated kraft paper and galvanized iron sheet, moisture-proof and anti-collision, adapting to various transportation methods such as sea and land transportation;
• Custom packaging for small coils: For small-batch and narrow-width slit coils, independent small coil packaging is adopted, and each coil is labeled with specifications, material and zinc coating thickness for convenient batch on-machine operation of customers.

4. Personalized Supporting Services

• Small-batch customization: Supporting slitting customization with a minimum order quantity of 1 coil, meeting the sample and small-batch production needs of small and medium-sized customers with no batch threshold;
• Urgent customization: A green urgent channel is opened, regular slitting orders are completed within 24 hours, and urgent orders are delivered within 12 hours to ensure customers' production schedules;
• Full-process traceability: Each batch of custom slit coils is provided with material certification and inspection report, marking the original coil batch number, slitting process parameters and inspection results to achieve full quality traceability;
• Free sampling: New customers can apply for free slitting samples, and conduct batch cooperation after confirming that the specifications and quality meet the requirements, reducing customers' trial and error costs.

5. Follow-up Technical Support

II. Core Precision Slitting Process for Bright Surface Galvanized Steel Coil

1. Overall Slitting Process Flow

2. Core Operation and Technical Points of Each Process

(1) Original Coil Loading: Soft contact loading to prevent coil deformation

(2) Uncoiling and Leveling: Precise leveling to eliminate internal stress of the coil

(3) CNC Width Setting and Positioning: Micron-level positioning to ensure precise width

(4) Precision Shearing: Imported cutters for burr-free shearing and non-shedding zinc coating

• Cutter configuration: Imported high-speed steel with tungsten steel inlay cutters are adopted with a cutter hardness of HRC62-65. The cutting edges are precision ground with high sharpness, achieving no chip adhesion and burrs during shearing. The cutters have strong wear resistance and can shear continuously without edge chipping, ensuring consistent shearing quality of slit coils in the same batch;
• Gap adjustment: According to the thickness and zinc coating thickness of the bright surface galvanized steel coil, the shearing gap of upper and lower cutters is automatically adjusted by CNC (the gap value is accurately controlled at 5% - 10% of the sheet thickness). Excessively large gap is prone to edge burrs and zinc coating falling off, while excessively small gap is easy to damage the cutters and cause edge warping of the coil. Precise gap adjustment achieves "smooth shearing and intact zinc coating";
• Soft contact protection: The material guiding rollers and pressure rollers in the shearing area are all wrapped with anti-static silica gel layer with moderate hardness, which is scratch-free and indentation-free in contact with the surface of bright surface galvanized steel coil, ensuring surface finish.

(5) Tension Coiling: Constant tension control for tight coiling without loose layers

(6) Edge Trimming: Light trimming to ensure smooth edges

(7) Quality Inspection: Full-item inspection to eliminate non-conforming products

• Dimensional inspection: Laser width gauge and micrometer are used to detect the slitting width and thickness. 5 detection points are randomly selected for each coil, with width tolerance ≤±0.1mm and thickness tolerance ≤±0.02mm;
• Surface inspection: Manual visual inspection + light inspection table are adopted to check for surface defects such as scratches, indentations and zinc coating falling off, ensuring the bright surface finish is consistent with the original coil;
• Edge inspection: Magnifying glass is used to check edge burrs with burr height ≤0.05mm, no cracking or warping at the edges;
• Coil shape inspection: Check whether the coiling is tight, with no tower shape or loose layers, and whether the inner hole and outer coil diameter meet the custom requirements.

(8) Custom Packaging & Finished Product Delivery: On-demand packaging for safe delivery

3. Core Equipment and Technical Advantages of Slitting Process

• Core equipment: A full set of CNC automatic precision longitudinal slitting lines are adopted, equipped with imported servo motors, CNC width setting systems, photoelectric deviation correction devices and laser testing equipment. The equipment automation degree reaches 100%, reducing manual intervention and errors;
• Cutter advantages: Imported tungsten steel cutters are matched with regular precision grinding by cutter grinding machine to ensure shearing effect;
• Protection advantages: The whole process adopts soft contact and scratch-free design, and all parts in contact with the coil surface are mirror rollers and silica gel rollers, fundamentally avoiding surface damage;
• Precision advantages: Dimensional positioning, shearing and deviation correction all realize micron-level control, with slitting precision much higher than the conventional industry standards, meeting the needs of customers for precision processing;
• Efficiency advantages: The feeding speed of a single slitting line can reach 80 - 120m per minute, and 1 - 10 narrow coils can be slit at the same time, balancing precision and production efficiency.

III. Quality Assurance Standards for Custom Slitting of Bright Surface Galvanized Steel Coil

1. Dimensional tolerance: Width ±0.1mm, thickness ±0.02mm, coil diameter deviation ≤±5mm;
2. Surface quality: No scratches, no indentations, no zinc coating falling off, no stains, and the finish is consistent with the original coil;
3. Edge quality: Burr height ≤0.05mm, no cracking, no warping and no edge curling;
4. Coil shape quality: Tightly coiled, no tower shape, no loose layers, no uncoiling, and smooth on-machine uncoiling;
5. Performance assurance: The tensile strength, yield strength and corrosion resistance of the coil after slitting are consistent with the original coil, without performance attenuation caused by the slitting process.