Air-line fitting

Last updated
Nipples with mating safety couplings Rtc-serie-171.08-gruppe.jpg
Nipples with mating safety couplings

Also known as pneumatic couplings, quick disconnects, air couplers, quick connect couplers, and quick couplers, hand-operable air-line fittings allow manual disconnection of gas supply lines, including compressed air and breathable air (a subset of breathing gases). Most fittings do not have regional standardization but have become de facto standards through popular adoption.

Contents

Mechanical structure

Pneumatic tool attached using a coupling Fur working tools, nailing with stapler.JPG
Pneumatic tool attached using a coupling

A coupled pair consists of a male nipple or plug and a female coupler or socket. One side is connected to a flexible supply hose; the other may be attached to a manifold, valve, tool, or another hose. A female coupler is used on the supply side, and a male nipple is used on the receiving side.

Fitting profiles have identifiable geometry on the male end, but care must be taken to use a compatible coupler. Couplers use springs and balls to lock mating nipples into place. A seal is effected using O-rings along the shaft of the nipple or by compression by the tip. Although incompatible pairs may latch, the sealing performance may be compromised.

Features

Breathable air applications

For breathable air applications such as SCBA, these may found on both sides of the first-stage and second-stage pressure regulators (very similar to SCUBA diving regulators) to allow for rapid and tool-free return-to-service. [1] For breathable air applications such as supplied-air and mixed supplied-air with SCBA backup, the quick-disconnect fittings allow movement of a worker from one supplied-air station to another.

Other applications

These fittings or special-service variants may also be found in hydraulic applications and alternative compressed gas applications (Oxy-acetylene welding and cutting, fuel gases, NSF C-2 food-contact, etc.).

Common fitting profiles by size

European convention uses DN (nominal diameter) to denote a nominal size of each fitting. Various manufacturers specify series or styles for each profile. Fittings are commonly referred to by their manufacturer name/series, i.e., "Rectus 25" for the common European standard. Proprietary designs supported by a single manufacturer are not included in this table. [2] [3]

Manufacturer Series
ProfileDescriptionDNStandardsRTCCEJNRectusParkerMiltonPCLWalther
Walther2.5.svg German/Walther 2.52.5200.0314150LP-002
Walther2.7.svg German/Walther 2.72.702020/9106-003
Us-18hp.svg US Industrial 1/8" HP3ISO 6150C170.03303
German-camozzi.svg German/Camozzi/EWO/Kani502122321/90
Schrader-14.svg Schrader 1/4"5017.0617TLPF
Us-14.svg US Industrial 1/4"5.3/5.5A-A-59439, ANSI T3.20.14-1990, MIL-C-4109F, ISO 6150B02331023/2420/30MISO B12
Us-14-hp.svg US Industrial 1/4" HP5.5ISO 6150C170.0629118
Truflate-14.svg Tru-Flate/Automotive 1/4"10T
Aro-210.svg ARO 2105.5014/02230014/2250AA Style
Lincoln-air-nipple.svg Lincoln 70L
Pcl-air-nipple.svg UK/English Industrial/PCL5.501919Standard
Walther-6lp.svg German/Walther 6 LP6200.0552LP-006
Walther-6sp.svg German/Walther 6 SP6200.0651SP-006
Scandinavian-6.5.svg Scandinavian 6.5/7.46.5/7.4032.0630331/1300
Euro-7.2.svg Hi-Flow/Eurostandard 7.27.2/7.4025/02632025/26VXF-Euro
Nitto-air-nipple.svg Asian/Japanese/Nitto7.501331513KF
Truflate-38.svg Tru-Flate/Automotive 3/8"10P
Us-38.svg US Industrial 3/8"8.2/8.5A-A-59439, ISO 6150B0304303020/30H
Us-38hp.svg US Industrial 3/8" HP8ISO 6150C170.0838184
Aro-310.svg ARO 3109014.0940AA
Scandinavian-9.5.svg Scandinavian 9.5/109.5/10032.1040832/1800
Euro-10.svg Eurostandard 101002741027
Schrader-12.svg Schrader 1/2"017.10TL
Us-12.svg US Industrial 1/2"11A-A-59439, ISO 6150B0375503720/30G
Us-12hp.svg US Industrial 1/2" HP11ISO 6150C170.11471
Truflate-12.svg Tru-Flate/Automotive 1/2"10G
Walther-12.svg German/Walther 1212200.1257LP-012

See also

References