Lubrication Systems: What to Know About In-Die and Coil Lubrication

Few things are more important in the metal stamping industry than adequate in-die lubrication and coil stock lubrication systems. But what are they exactly?  What are your options and how do you decide what's best for your needs?  Let's dive in!

What Are In-Die Automatic Lubrication Systems?

In-die automatic lubrication systems are specialized mechanisms designed to apply lubricant precisely within a stamping die during metal forming processes. These systems ensure that moving parts, such as punches, dies, and slides, receive the right amount of lubrication at the right time. Below we look at why they matter.

Importance of In-Die Lubrication Systems

• Reduced Wear and Friction:
  • Proper lubrication minimizes wear and friction between metal surfaces, extending tool life and reducing maintenance costs.
• Enhanced Part Quality:
  • Consistent lubrication prevents galling, scoring, and surface defects on stamped parts.
• Increased Productivity:
  • Automated lubrication eliminates manual application, allowing continuous production without interruptions.
• Safety:
  • Reduced manual handling of lubricants improves workplace safety.

Types of In-Die Automatic Lubrication Systems

• Spray Systems:

  • Airless Spray: These systems use hydraulic pressure to atomize lubricant into fine droplets, ensuring precise application. Ideal for high-speed presses.
  • Air-Mixed Spray: Combines lubricant with compressed air for controlled dispersion. Suitable for various applications.
  • Mist Systems: Deliver a mist of lubricant particles, providing even coverage.

• Roller Systems:

  • Roller Lubricators: Rollers apply lubricant directly to the sheet metal surface as it enters the die. Effective for continuous strip feeding.
  • Brush Roller Systems: Brushes evenly distribute lubricant across the metal surface.

• Pad Systems:

  • Felt Pads: These absorbent pads hold lubricant and transfer it to the metal during each stroke. Simple and reliable.
  • Sponge Pads: Similar to felt pads but use a sponge-like material for controlled lubricant release.

• Wick Systems:

  • Wick Feeders: Wick-based systems draw lubricant from a reservoir and deliver it through capillary action. Suitable for low-volume applications.

Choosing the Right IN-DIE Lubrication System for Your Equipment

Consider the following factors:

• Application Type:

  • High-speed presses require precise spray systems.
  • Roller systems work well for continuous strip feeding.
  • Pad or wick systems suit slower presses.

• Lubricant Type:

  • Choose a system compatible with your lubricant (oil, grease, or dry film).
  • Consider viscosity, additives, and environmental impact.

• Die Design and Geometry:

  • Evaluate the die layout, part complexity, and access points for lubrication.
  • Ensure the system reaches critical areas.

• Maintenance and Refilling:

  • Opt for systems that allow easy refilling during operation.
  • Consider maintenance intervals and ease of cleaning.

• Budget and ROI:

  • Balance initial investment with long-term benefits.
  • Calculate savings from reduced downtime and improved part quality.

What Is Coil Stock Lubrication?

Coil stock lubrication ensures proper lubrication of metal coils (sheets or strips) before they enter the die. It’s essential for efficient stamping processes.

Why Is It Important?

• Die Protection: Lubricated coils prevent galling and scoring on dies.
• Consistent Lubrication: Evenly coated coils lead to better part quality.
• Reduced Friction: Lubricated stock reduces wear and heat during forming.

Types of Coil Stock Lubrication Systems:

• Roller Lubricators:

  • Evenly coat the material (top and bottom) before it enters the press.
  • Reliable and widely used for stock lubrication.

• Spray Cabinets:

  • Ideal for lubricating the top and bottom of coil stock.
  • Adjustable spray nozzles for precise application.
  • Some systems recycle run-off lubricant.

Automatic In-Die Lubrication Versus Coil Stock Lubrication

What is better, in-die lubrication or coil lubrication? Or should you use both?

Both in-die lubrication and coil stock lubrication serve essential purposes, and the choice depends on your specific production needs:

• In-Die Lubrication:

  • Advantages:
    • Precise application directly within the stamping die.
    • Minimizes wear, friction, and heat during metal forming.
    • Enhances part quality and extends die life.
  • Ideal For:
    • High-speed presses.
    • Applications requiring controlled lubrication.
  • Considerations:
    • Consumes more lubricant than coil stock systems.

• Coil Stock Lubrication:

  • Advantages:
    • Lubricates the entire coil before it enters the press.
    • Ensures consistent coverage across the entire sheet or strip.
    • Reduces defects and improves part quality.
  • Ideal For:
    • Continuous strip feeding.
    • Efficient stamping processes.
  • Considerations:
    • May not provide precise point-to-point lubrication.

• Using Both:

• • Combining both methods can be beneficial:
    • Pre-Lubrication: Coil stock lubrication prepares the material.
    • In-Die Lubrication: Ensures precise lubrication during forming.

Choosing the Best System

Consider your specific process, lubricant type, and budget. Roller lubricators provide complete control, while spray cabinets offer targeted lubrication where needed.

Check out the offerings from PAX on our In-Die & Coil Stock Lubrication page or contact PRI to have one of our expert application engineers consult with you to help you choose the best in-die automatic lubrication and/or coil lubrication systems for your equipment and specific production needs.