Trays: Types & Features

Single Use and Reusable Trays:

Refers to the intended life cycle of a tray or package.  Single Use Trays are generally considered to be:

  • Thin gauge material, use least amount of material possible.
  • Lower initial purchase cost, but recurring expense.
  • Disposed of after its intended single use.  With a good sustainability plan, it would be recycled.

Reusable Trays are generally considered to be:

  • Thicker gauge material.  This is subjective and dependent upon each applications as most of the trays we design and manufacture have the ability or potential to be reused.
  • Higher initial purchase cost, but with minimal recurring purchases.  Often times, the purchase can be considered a capital expense and treated as an asset rather than an expense.
  • Used over again continually in a closed loop system.  With a good sustainability plan, it would be recycled after its useful life.

Tray Stack Features:

  • Tray-to-Tray stack design.  The tray does all the work.  The tray positions and retains the part.  It also supports the weight of the finished stack.  No stack weight is transferred to the product.
  • Tray-to-Product stack design.  In this design style, the tray positions and retains the part.  The stack weight is supported by a combination of the tray and product.  Product must be durable enough for this type of design feature.
  • Product-to-Product stack design.  In this design style, the tray is only used to position and retain the product.  The tray is essentially only an interleave layer between the products.  The product is then used to support the weight of the stack.  Product must be durable enough for this type of design feature.

Stack / Nest Tray feature:

The stack/nest tray feature is very common with component trays.  The feature allows the trays to nest in the common tray-tray orientation, but stack when the tray orientation is rotated 180 deg from the last tray in the stack.  Trays are designed with some type of orientation feature (text, stripe, design feature, etc…) to assist the operator with the proper tray orientation per layer.

The nesting of the trays is used to minimize storage space required when the tray is not in use, thus reducing cost.  The stack feature of the tray is used to protect and contain the product.  This feature is most common with the tray-to-tray stack design, but could be incorporated into the other stack types as well.  Depending upon the product shape, the feature also often allows for better utilization of vertical space within the tray stack.

   

Stack-Only Trays:

The stack-only tray feature is used in some robotic handling requirements, when tray nesting is not a desired feature or when rotation is not desired for stacking.

With stack-only trays, the tray uses the same amount of space whether it is full of product or empty awaiting use.  Design features such as key-ways are used to keep the stacked tray in the proper orientation and allow for proper stacking.

Stack-only tray with alternating rotate – Heavy gauge material:

Stack-only tray with straight stack – Thin gauge material:

Trays with Covers:

This tray packaging concept provides many benefits.

  • Totally product containment.
  • Eliminates potential for environment contamination.
  • Nestability of packaging when not in use.
  • Ease of stackability when in use.

Trays for Robotic Handling / Auto Feeding:

Trays are easily engineered to robotic handling and automatic feeding for automated production lines.  The type of automation you have or require determines the tray criteria.

Some of the key engineered design tray features to consider are:

  • Tray engagement with the robot/automation.
  • Tray to tray consistency.
  • Tray rigidity requirements.
  • Tray stackability.
  • Tray de-nestability.

Stack only trays designed for robotic handling and automatic feeding:

Stack/Nest Tray with stripe for orientation designed for robotic handling and automatic feeding:

Thin gauge, single use insert tray with heavy gauge, reusable carrier tray.  Insert tray is automatically fed into carrier tray.  Carrier/insert tray then automatically moved through clients production process:

 

A common automatic feeding problem, especially with thin gauge trays, is getting the parts to separate as a single unit for introduction into the production line.  Often times a denest-lug is incorporated.  A denest-lug is a design feature which keeps the trays separated to the point that side wall interference is eliminated allowing the trays to denest easily.

Denest-Lug Tray     Denest-Lug Tray 2

 

Above photos show 2 styles of thin gauge trays which utilize the denest-lug feature.  Trays are very consist and ready for auto feeding.

Example of a bad denest-lug design

 

However, proper design and consistency is critical.  Poorly designed or formed denest-lugs can actually make auto-feeding more difficult than if there were no denest-lug at all.  The picture above shows a stack of thin gauge trays with poorly designed denest-lugs.  The stack when slightly compressed during handling or loading into the automated process actually cause the denest feature to lock-on to each other and make consistent auto-feeding impossible.

If you have experienced this problem, ask us about our proprietary denest-lug design feature.

Contact Us for More Information or to Get a Quote