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High-Performance Expansion Sealing Plugs

High-performance expansion sealing plug for higher pressure: the expansion band is longer, spreading the sealing contact over more bore length.

Key specifications

MaterialBrass / Stainless Steel
Installationthreaded in with radial or face sealing
StandardGB/T 197, GB/T 3452.1
Typical substrateprocess and test ports
Key inspectionspressure hold, seal hardness

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Product overviewOverview

Process holes are often not precision-machined, so roundness and roughness vary. A longer expansion band spreads the contact pressure and reduces the effect of bore imperfections, which is what allows higher pressure ratings. The trade-off is a higher setting force and a bore that has to be straight over the full band length.

Material: Brass / Stainless Steel. It is threaded in, sealing either radially or on the face.

Key featuresFeatures

Longer band tolerates bore imperfections but needs a straighter bore.
Expanding designs compensate for hole size variation in as-cast ports.
Integrated O-ring or rubber sleeve seals on installation without sealant.
Magnetic versions capture ferrous debris and keep circuits clean.

Typical applicationsApplications

Pneumatic component bodies
Pump and compressor housings
Hydraulic manifold process holes

Selection notesSelection

Check bore straightness over the band length, not just at the sealing point; a bore that tapers over that length gives uneven contact and a lower pressure rating.

Frequently asked questionsFAQ

What limits the pressure rating of an expansion plug?

Contact pressure and bore quality. A longer band helps, but if the bore is tapered or scored the contact is uneven and the joint leaks at a lower pressure than the rating suggests.

What matters during installation of the High-Performance Expansion Sealing Plugs?

Thread it in, sealing either radially or on the face. Longer band tolerates bore imperfections but needs a straighter bore.

Specifications

Material	Brass / Stainless Steel
Sealing	O-ring seal
Standard	GB/T 197, GB/T 3452.1
Head style	pan head
Installation	threaded in with radial or face sealing
Typical substrate	process and test ports
Key inspections	pressure hold, seal hardness

Manufacturing and inspection

Pressure hold test at 1.5 times working pressure, recording decay.We recommend a pilot assembly at the actual torque and mating part before locking the process parameters for volume.