1600mm Slitting Line for 4mm Steel Coils A Complete Guide for Steel Processing Manufacturers

In the steel processing industry, precision and efficiency define competitiveness. Whether you’re supplying steel coils for construction, automotive, or appliance manufacturing, one key machine ensures your material fits every customer’s specification — the Slitting Line.

Among various configurations, a 1600mm Slitting Line for 4mm thick steel is one of the most practical and widely used setups in medium-to-heavy coil processing plants. It’s designed for high-accuracy slitting of medium-thickness coils while maintaining high speed, consistent quality, and easy operation.

This blog will walk you through how the machine works, what benefits it offers, and what you should consider when choosing one for your factory.

What Is a Slitting Line?

A slitting line (or coil slitting machine) is a production system that cuts a wide steel coil into multiple narrower coils — known as strips — according to specific width requirements.

It’s commonly used in steel service centers and metalworking plants to prepare material for roll forming, tube mills, stamping, and laser cutting.

A 1600mm slitting line means it can process coils up to 1600mm in width, and a 4mm capacity refers to the maximum thickness of steel it can slit efficiently, whether cold-rolled, hot-rolled, galvanized, or stainless steel.

Basic Working Process

A standard 1600mm slitting line includes several coordinated sections. From coil loading to rewinding, each part ensures smooth material flow and precision.

Main Components:

1. Hydraulic Decoiler (10–20 Tons)

   • Holds and uncoils the mother coil.

   • Equipped with pressing arm and coil car for easy loading.

2. Pinch and Leveling Section

   • Flattens coil head and tail to ensure smooth feeding.

   • Reduces coil memory and improves slitting precision.

3. Slitting Head (Slitter Machine)

   • The core part of the line.

   • Uses upper and lower rotary knives to cut the coil into required strip widths.

   • Blades are made from SKD11 or D2 tool steel for durability and accuracy.

4. Scrap Winder

   • Collects the edge trimmings (waste strips) during slitting.

5. Tension Unit & Looping Pit

   • Maintains coil tension and buffers length difference between decoiling and recoiling speeds.

6. Recoiler (10–20 Tons)

   • Rewinds the slit strips into smaller coils.

   • Equipped with a hydraulic pressing arm and coil separator for tight, even winding.

7. Discharging Car & Stacking Table

   • Automatically unloads finished coils for packaging or further processing.

The entire process is controlled by PLC + touchscreen HMI, ensuring automatic synchronization, safety, and precision control.

How the Slitting Line Works

Let’s look at the process from the operator’s perspective:

1. Coil Loading – The operator loads a steel coil (up to 1600mm wide, 4mm thick) onto the decoiler using the coil car.

2. Uncoiling & Leveling – The material head is straightened by the pinch and leveling section for smooth feeding.

3. Slitting Operation – The strip passes through the slitter head, where circular knives cut it into narrower strips.

4. Scrap Collection – Edge trims are wound separately onto scrap winders.

5. Recoiling – Each slit strip is rewound simultaneously into smaller coils.

6. Coil Unloading – The recoiled coils are automatically moved to the discharging table for storage or shipment.

This continuous process ensures high efficiency, minimal material waste, and perfectly uniform strips ready for downstream use.

Key Technical Specifications (Typical 1600mm Line for 4mm Steel)

These parameters can be customized based on customer needs, material type, and factory layout.

Why You Need a 1600mm Slitting Line for 4mm Steel

From a buyer’s standpoint, investing in a professional slitting line offers both economic and operational advantages:

1. Precision Cutting

   • Achieve ±0.1mm width tolerance, essential for roll forming and stamping industries.

2. High Productivity

   • Capable of processing up to 20 tons per coil at speeds over 100 meters per minute.

3. Versatility

   • Handles various materials: cold-rolled, galvanized, PPGI, stainless, or HR steel.

4. Cost Reduction

   • Buying wider coils and slitting them in-house lowers raw material cost per ton.

5. Better Inventory Control

   • You can prepare coil widths according to different production needs instead of relying on coil suppliers.

6. Stable Operation and Safety

   • Modern lines are designed with overload protection, hydraulic braking, and automatic alignment for operator safety.

What to Consider When Choosing Your Slitting Line

If you are evaluating a new line for your factory, pay attention to these critical aspects:

1. Material Type and Thickness Range

   • Choose machine structure and blade quality according to your heaviest and hardest material.

2. Slitting Accuracy and Speed

   • For automotive or precision applications, higher-speed servo feeding and knife shaft adjustment are essential.

3. Knife Change Convenience

   • Ask if the slitting head supports quick-change cassette type for faster setup and reduced downtime.

4. Recoiling Tension System

   • Hydraulic tension control ensures even winding, preventing telescoping or slack coils.

5. Line Layout and Space Requirements

   • A standard 1600mm line requires around 25–35 meters in length, depending on speed configuration.

6. Automation Level

   • Advanced lines feature automatic knife positioning, scrap handling, and coil separation, reducing operator labor.

7. After-Sales Support

   • Ensure your supplier offers full technical drawings, installation guidance, and long-term spare parts supply.

Real Applications of a 1600mm Slitting Line

This type of slitting line is widely used in:

• Steel service centers – preparing narrow coils for local customers.

• Construction material manufacturers – supplying strips for roll forming (roof panels, purlins, door frames).

• Automotive part factories – producing precision narrow coils for stamping.

• Pipe and tube mills – providing feed strips for welded tube production.

• Electrical steel suppliers – cutting coils for transformer and enclosure production.

Its versatility makes it an ideal investment for medium-sized coil processors aiming to expand into multi-purpose coil service.

Advantages from the Customer’s Perspective

As a buyer or operator, you’ll appreciate the tangible benefits this machine brings:

• Easy Operation – PLC control allows even new operators to handle coil width setup quickly.

• Durability – Heavy-duty frames and hardened shafts ensure long service life even under 4mm thick coil stress.

• Smooth Recoiling – Uniform tension control ensures neat and tight coils for easy downstream handling.

• Low Maintenance – Well-designed mechanical structure minimizes downtime.

• Customization – You can adjust slitting widths, number of strips, and cutting speed for each production order.

Simply put, the machine doesn’t just cut coils — it enhances your entire production capability.

Choosing a Reliable Supplier

Before purchasing, ensure your supplier provides:

• A full layout drawing and technical proposal.

• Real videos and photos of the working line.

• Transparent component brands (motors, PLC, hydraulics).

• Installation and training support after shipment.

• Reasonable warranty and spare parts policy.

Reliable suppliers not only deliver machines — they deliver confidence, stability, and long-term partnership.

Final Thoughts

A 1600mm Slitting Line for 4mm steel coils is an essential piece of equipment for any steel service center or metal product manufacturer aiming for quality, speed, and flexibility. With precise knife adjustment, advanced tension control, and automated coil handling, it ensures smooth, high-accuracy slitting even for thick steel materials.

From construction profiles to automotive components, this slitting line allows you to prepare raw material that meets exact customer specifications — consistently and efficiently.

As the global demand for customized coil widths continues to grow, investing in a reliable slitting line isn’t just a production upgrade — it’s a strategic step toward building a smarter, more competitive steel processing business.