Experts in Silicone Gasket Solutions
Experts in Silicone Gasket Solutions

Stocked Products / Off-the-shelf

Foam Port Plugs

Chamber E-Plugs, port plugs, foam port plugs, E-Plugs port seals for environmental test chambers

Chamber port plugs shown in various cylindrical sizes, esd coated e-plug with pull handle

Stockwell Elastomerics manufactures a variety of standard, semi-custom and custom silicone foam port plugs for environmental test chambers, with product name E-Plug™. These products are fabricated from silicone foam having a functional temperature range of -55°C (-67°F) to 200°C (392°F).

Rectangular and cyllindrical port plugs with gray HT-820 on both sides of white MF-1 foamMany OEMs who manufacture ruggedized equipment often use gaskets, seals, cushion pads and other elastomeric components made by Stockwell Elastomerics. “Rugged” could simply mean an electronic device that can survive being rained on, while others must function in extreme temperatures, rain, water submersion, high humidity, salt spray, etc. Very often the gaskets and seals for these devices are manufactured from silicone rubber due to its wide temperature range, soft durometers, UV resistance, and good resistance to humidity and salt fog.

To ensure that an engineering design is robust enough, devices may be lab tested for some or all of the mentioned conditions in an environmental test chamber. It’s common for these test chambers to have access ports for cabling – so it makes sense that the sealing plugs for these chambers be manufactured from silicone materials as well to withstand many test cycles. In response to this need for port plugs used with environmental test chambers, Stockwell Elastomerics developed and manufactures standard and custom environmental test chamber port plugs used by test engineers.


Thermal Properties

E-plugs from Stockwell Elastomerics are made of a 4″ thick layer of ultra-soft open cell silicone foam. This foam provides great thermal insulation as its thermal conductivity is 0.044 W/m-K. Due to the material thickness, this equates to a thermal port plug with an R value of 13.1 (ft2•°F•h/BTU).


Standard E-Plug™

Stockwell Elastomerics offers standard sized E-Plugs™ – environmental chamber access port plugs that are conformable to allow the pass through of cables, and also offer excellent thermal insulation. Standard E-Plugs™ are 4″ thick with a thin closed cell silicone foam top layer. E-Plugs™ are slightly oversized to make a press fit into the test chamber. Standard E-Plugs™ are available and ready to ship in the following sizes:

  • E-Plug™ 8 – for 8″ OD port (8.25″ OD actual)
  • E-Plug™ 6 – for 6″ OD port (6.25″ OD actual)
  • E-Plug™ 5 – for 5″ OD port (5.25″ OD actual)
  • E-Plug™ 4 – for 4″ OD port (4.25″ OD actual)
  • E-Plug™ 3 – for 3″ OD port (3.25″ OD actual)
  • E-Plug™ 2 – for 2″ OD port (2.25″ OD actual)

Port plug shown with wire harness installed along with cylindrical and cubic ESD coated plugs Semi-Custom E-Plug™

Semi-custom E-Plugs™ are made in the standard E-Plugs™ sizes but with added features, listed below. To specify a semi-custom E-Plug™, add one of the suffixes to the standard size to designate the feature.

  • E-Plug X-CC – Concentric Cut, allows more conformity for cables
  • E-Plug X-EC – ESD coated to reduce static buildup

Example: E-Plug 5-CC is a 5.25″ OD E-Plug with a 3.0” diameter concentric cut to allow a ribbon cable installation.


Custom Feature E-Plug™

Custom feature E-Plugs™ are made in the standard E-Plugs™ sizes but with added features, listed below. To specify a custom feature E-Plug™, add one of the suffixes to the standard size to designate the feature.

  • E-Plug X-PH – Pull Handle, for easier removal

Example: E-Plug 6-PH is a 6.25″ OD E-Plug with a pull handle added.

Various sizes of circular and rectangular E-plugs shown stacked

Custom Sizes for E-Plugs™

Stockwell Elastomerics often provides custom thermal port plugs, made to customer specified geometries. For example, many chamber openings are rectangular – just figure on adding .25” to the length and width for a snug fit. Most custom environmental test chamber plugs are manufactured from the same 4″ thick, high and low temperature silicone foam, offering excellent conformability and thermal insulation.

Contact Stockwell Elastomerics for Chamber Port Plugs

Contact Us for further assistance with silicone foam port plugs and thermal port plugs, including standard E-Plugs™, semi-custom E-Plugs™, custom feature E-Plugs™, and E-Plugs™ in custom sizes for use with environmental test chambers.

E-Plug™ is a trademark of Stockwell Elastomerics, Inc.

Contact Stockwell Elastomerics

Request a quote or get more information.