Drilled Hole Sealing Plugs - Koenig Expanders

Koenig sealing plugs seal holes with complete reliability. Expansion plug technology forms a 100% leakproof metal-to-metal seal

Koenig Expanders seal holes utilizing expansion technology which forms an unsurpassable metal-to-metal seal.
Koenig sealing plugs have revolutionized drilled hole sealing in nearly every advanced industry. 5 billion units have been installed globally with failure rates below 1PPM.
From hydraulics and motorsports to automotive and aerospace applications, Koenig expanders reliably plug holes, stopping leaking under high pressures in extreme environmental conditions.

Pull-type expanders

The integrated mandrel of the pull-type Expander inserts the plug into the hole, before retracting it back to form an anchored seal. Pull-style expanders are ideal when holes are located across different faces, offering maximum flexibility. Mandrel expanders require no counterbore or pre-machining. They can be set quickly using a hydro-pneumatic or battery powered hand tool which is easily integrated into an assembly or production line.

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Push-type expanders

Push-style, ball type Expanders require a counter bored hole. The plug is positioned up to the counter bore face. The ball is pressed into a seated cup. The ball causes the serrated grooves to expand and anchor into the substrate material, forming a secure metal-to-metal seal. Ball type expander plugs require a setting tool that is fitted to a press, or for accuracy and repeatability with stroke control, an Express 3000/5000 Hydro-pneumatic Press.

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