+ Molded Parts

Many of the products we offer to our customers are custom parts. Most are molded rubber products. These parts are made to our customer’s exact specifications and are proprietary to our customer. These parts require that tooling is made to produce the parts. There are several processes that are used for these parts and include injection molding, transfer molding, or compression molding.



Injection molding is the process of feeding uncured rubber from a hopper into a heated barrel. The elastomer is then pushed by a screw-type plunger into a heater chamber.  The material flows through a gate & runner system into the mold cavity. The mold remains at the proper temperature until it is cured.

Advantages of this method:

  • Quicker cycle time
  • Custom shapes with little flash
  • Supports a wide range of harnesses (durometers)


Transfer molding is the process of placing uncured rubber into part of a mold called a pot.  When the ram is closed, the elastomer flows into the cavity through a runner & gate system.  The rubber remains under high temperature and pressure until fully cured.

Advantages of this method:

  • Mid-to-high volumes
  • Shorter cycle times vs. injection molding
  • Supports complex geometries & tight tolerances


Compression molding is the process of forming uncured rubber into the desired shape.   The first step is to pre heat the rubber until it is pliable & it is placed into an open mold cavity.  Next, the mold is closed to force the elastomer to fill the cavity, where the rubber is kept under heat and pressure until fully cured.

Advantages of this method

  • Lower tooling cost
  • Small production runs
  • Suitable for larger -heavier parts

Just like our O-ring offering, these parts are available in a wide variety of materials, harnesses (durometers), and colors.  The variety of what could be classified as a molded part is extensive and includes but not limited to:

  • Seals
  • Custom shapes or parts
  • Bumpers
  • Grommets
  • Hoses
  • Diaphragms
  • Duck Bill Valves
  • Caps or Plugs
  • Vibration or Shock Isolators
  • Insert Molded products
  • Rubber-to-metal products

We love to work with our customer with custom molded rubber products.  Taking it a step further, we can often combine the molded rubber with other parts of a component to reduce assembly cost for our customers.  Our application engineers welcome a discussion on designing a custom molded part or combining a molded rubber product with other sub-components to reduce the overall cost of your product.  Contact Us and let’s get started on YOUR project.  You won’t be disappointed!



Packing Seals & Engineering has provided sealing products and solutions since 1959. We realize that you have many options available for obtaining sealing products, but what matters most is that you find the right seal for YOUR needs. Why trust anyone else but the experts...

211 Glenn Bass Rd, Fitzgerald, GA 31750

Tel: (423) 562-1205 | Fax: (423) 562-4575


+ Our standard and custom O-rings are offered in a wide range of materials. Click to view O-Rings


+ Click to view details about our custom molded seals & parts


+ Click to view more information about O-Ring Failure

ISO9001:2015 Certification

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