ITHM Internal Quick Connectors Vacuum Leak Testing

Overview of ITHM Internal Quick Connectors

The ITHM series internal quick connectors are designed for pressure and vacuum testing, filling, sealing, and venting of internally threaded components. Intended for industrial clients and business buyers operating leak test stations on assembly lines, each connector is inserted into the threaded bore and rotated by hand until the O-ring contacts the end face of the test piece. No wrench, sealant, or thread tape is required to establish a seal. The connector can be configured as a through-type with a medium inlet, as a through-type with a rotary joint, or as a plug, adapting to different test circuit layouts. Manufactured by Hefei Yuanzhi Automation Technology, the ITHM line supports metric (M), G (BSPP), BSPT, NPT, and UNF thread standards across a broad size range.

Key Design Features of ITHM Quick Connectors

Materials and Construction

The main structural components are machined from corrosion-resistant stainless steel for long service life in production environments. The standard sealing material is nitrile rubber (NBR), which covers most air and inert-gas testing requirements. Custom seal materials and special dimensions can be developed according to customer specifications, particularly for applications involving elevated temperatures, aggressive media, or limited installation space.

Pressure Rating and Sealing Performance

The ITHM series supports both positive pressure and vacuum testing. Maximum working pressure varies by thread size and type: small G-thread sizes (G1/8″, G1/4″) are rated up to 345 bar, mid-range sizes (G3/8″ through G1″) up to 276 bar, while larger sizes decrease to 210 bar (G1½″) and 172 bar (G2″). Metric, NPT, and UNF models follow comparable size-based pressure ratings. The reference leakage rate is 10⁻³ mbar·L/s, equivalent to 10⁻⁴ Pa·m³/s. Lower leakage rates are achievable depending on test method, operating conditions, and test piece surface quality, including seal surface treatment, roughness, and dimensional tolerances.

Technical Specifications for ITHM Internal Quick Connectors

Quick-sealing connector with medium inlet

Fast connector with a medium inlet and rotary joint

According to The Metric ISO Thread Standard

ITHM Series Fast Connector Specification Table

Operating Steps for ITHM Quick Connectors

Insert the ITHM connector into the internally threaded hole.

Rotate the connector by hand until the sealing O-ring contacts the end face of the test piece and is properly compressed.

Connect the test medium supply and apply the required test pressure.

After testing, release the test pressure completely before unscrewing and removing the connector.

Applications of ITHM Internal Quick Connectors

ITHM internal quick connectors are deployed in automotive component manufacturing, hydraulic manifold testing, pneumatic valve assembly, plumbing fixture production, and industrial equipment leak testing where internally threaded ports require pressure decay, vacuum decay, or flow verification. The internal insertion design minimizes the connector footprint outside the test piece, making it suitable for fixtures with limited clearance. The optional rotary joint configuration accommodates test setups where the supply line needs to rotate freely during connection.

Ordering Information for ITHM Quick Connectors

When requesting a quote, please specify: part number or thread type and size, required pressure range, test medium and target leakage rate, operating temperature range, available space, and the test piece specification or CAD drawing. Custom thread sizes, seal materials, and dimensional variants can be developed based on sample evaluation.

FAQ About ITHM Internal Quick Connectors

What thread standards are available for ITHM connectors?

The ITHM series covers metric (M), G (BSPP), BSPT (tapered), NPT, and UNF internal thread types.

What is the difference between G-series and B-series connectors?

G-series connectors use parallel (BSPP) thread engagement, while B-series connectors use tapered (BSPT) thread engagement. Both share the same dimensional and pressure ratings.

What is the maximum test pressure?

Small sizes (G1/8″, G1/4″) are rated up to 345 bar. Mid-range sizes (G3/8″ through G1″) support up to 276 bar. Larger sizes are rated 210 bar (G1½″) and 172 bar (G2″).

Can ITHM connectors be used for vacuum testing?

Yes. The ITHM series is designed for both positive pressure and vacuum (negative pressure) testing.

What does the "S" suffix part number represent?

The "S" suffix denotes the return adapter connector, which provides a rotary joint interface for test circuits requiring rotational freedom.

Are custom sizes available?

Yes. Items marked as available upon request can be customized to customer specifications, including thread size, overall length, and seal material.