When customers think about extrusion die maintenance, they often focus on cleaning flow surfaces, inspecting lips, or checking overall die performance. While those are all important, one of the most common issues encountered during field service visits comes from something much smaller: worn wearable parts.

These components may seem insignificant on their own, but overlooking them can quickly lead to production downtime, unexpected repairs, and reduced product quality. After servicing dies in facilities around the world, I’ve learned that a proactive approach to wearable parts is one of the easiest ways to improve equipment reliability and avoid costly shutdowns.  

What Are Wearable Parts?

Every extrusion die contains components that naturally wear over time through normal operation. These include adjustment hardware, fasteners, heaters, gaskets, seals, and other serviceable items designed to be replaced periodically.

Unlike major die components, wearable parts are expected to experience gradual wear. The key is replacing them before they create larger maintenance issues.  

Why They Matter

During maintenance training and routine service visits, we emphasize cleaning the die’s critical surfaces—but that’s only part of the equation. Worn adjustment screws, damaged seals, or fatigued bolts can affect die performance just as much as contamination inside the flow channel.

When wearable parts are ignored, the consequences can include:

• Unplanned production down time 

• Polymer leaks and sealing issues 

• Inconsistent die adjustments 

• Reduced product quality 

• Higher repair costs due to damage to surrounding components

  
  

Our field service team offers classroom-style training on die maintenance for customers all over the world. During these sessions, as well as on our standard service visits, we stress the importance of properly cleaning a die’s critical surfaces to ensure smooth operation. This includes the areas where coating or polymer moves through the die’s flow channel, as well as the points where die bodies meet to form a seal. 

 

Common Small Part Issues We See in the Field

Part Type	Common Issue(s)	Potential Impact
Adjustments	Worn or damaged threads Material is bent or warped Debris has collected in the threads	Adjustments will not move and could damage a larger, more costly die feature (like a restrictor bar or die lip)
Fasteners	Worn, damaged, or stretched threads Rounded head	Bolts could seize and break causing difficulty in removing or installing during cleaning or operation
Heaters	Bent or broken Autoflex heater Damaged heater lead Heater has burned out	If an Autoflex heater is damaged, the system will not properly operate to adjust the die lip  Uniform heat is not delivered to the die bodies and could cause cold spots, creating flaws in the final product
Gaskets	Gasket was not properly installed or has been tightened too much Gasket has become brittle from production use	A pinched or damaged gasket could result in leaking
Seals	Seals are broken, dirty, or were improperly installed	Seals that are not properly installed could cause leaking

 

Stocking Replacement Parts
As a general guideline, Nordson recommends maintaining spare inventories for adjustment components, fasteners, heaters, and sealing components based on your specific die configuration. Having commonly replaced components readily available allows maintenance teams to complete repairs quickly instead of waiting for replacement parts during an unexpected shutdown. A full list of your die’s parts, including the wearable components, can be found on the assembly prints provided with your operation and maintenance manual or by contacting the EDI® Aftermarket Services team.    

Adjustment Components 

Inserts, Nuts, Retainers, Rods, Screws

The size will vary based on length and adjustment spacing. Nordson recommends you stock the following supply of spare adjustment parts:

• Adjusting Screws - 25% of the total quantity required for your die

• Inserts & Nuts - 35% of the total quantity required for your die

• Retainers - 10% of the total quantity required for your die

• Retainer Screws & Bolts - 100% of the total quantity required for your die 

 

Fasteners

Bolts & Washers

Different types of bolts and washers are used to secure or separate the die bodies from one another. Nordson recommends you stock the following supply of spare bolts and washers:

• Body Bolts - at least 10% of the total quantity required for your die

Note: The body bolt manufacturer highly recommends that the body bolts are replaced whenever the bolts are untorqued due to the nature of the heating and cooling process. DO NOT replace body bolts with a lower grade of bolt as operator injury may occur due to bolt breakage.

• Body Bolt Washers - 100% of the total quantity required for your die

• Jack Bolts - 2  

Heaters

Cartridge Heaters & Plugs

Heater types will vary based on your die’s processing parameters. Nordson recommends you stock the following supply of heaters and plugs:

• Autoflex Heaters - 10% of the total quantity required for your die

• Heaters - 10% of the total quantity required for your die 

Gaskets & Seals 

Gaskets and seals help prevent leaking from the die at various points. The gaskets and seals installed in your die will vary based on the optional features selected, as well as your processing parameters: Nordson recommends you stock the following supply of spare parts:

• End Seal Gaskets - Minimum of 4 sets

• End Seal Screws - 100% of the total quantity required for your die

• Restrictor Bar Seals - 1 roll

Nordson has created several suggested replacement part lists, based on our different product offerings.

 

Questions? 

Our aftermarket team is here to help support with inspections, maintenance, refurbishment solutions and more.

Contact Cory with your questions or to schedule your field service visit.