Oetiker -Technical Data for 1-Ear Clamps with Mechanical Interlock
Technical Data for 1-Ear Clamps with Mechanical Interlock Product Groups 105 & 155
Economical, quality clamp for low-pressure applications. Developed for a variety of applications in automotive systems, general industry and fluid distribution systems that incorporate plastic transition fittings and tubes. With this design of clamp, the mechanical interlock ractically eliminates the potential for localized corrosion, a potential failure mechanism at the heat-affected zone of a welded connection.
– 105 Galvanized or zinc-plated steelband
– 155 Stainless Steel, Material no. 1.4301 / UNS S30400
Size range Width x thickness
10.5 - 116.0 mm 7.0 x 0.6 / 0.75 mm
OETIKER 1-Ear Clamps with the Mechanical Locking design are made, in the standard version, from SAE 1008/1010 – DIN 1.0338 with a GALFAN corrosion protection coating to EN 10214, or from an austenitic stainless steel. The latter material is designated DIN 1.4301 / UNS 30400, an 18% chromium, 8% nickel alloy. This alloy acquires additional strength through cold working, during strip processing and clamp manufacture. The chemical composition and mechanical properties provide the exceptional combination of toughness and ductility, which are a prerequisite for the clamp closure process.
Stringent controls are maintained at the OETIKER strip processing facility, conditioning the slit material and forming a machined or rolled edge radius. This process reduces the potential for damage caused by sharp or square edges, when the clamp compresses adjacent material.
Carbon steel clamps coated with the GALFAN process provide a level of corrosion resistance expected by general industry standards. This
coating ensures that the clamps will withstand a minimum of 144 hours neutral salt-spray when tested in accordance with DIN 50012 /
ASTM B117, without base-metal corrosion. The chemical composition of DIN 1.4301 / UNS S30400 is practically immune to the neutral salt-spray procedure and has excellent resistance to many alternative corrosive environments.
The integrated dimple in the ear effectively increases the retained radial force and provides a spring effect when the diameter or the
application expands or contracts due to thermal or mechanical influences (i.e. vibration).
Using tools designed or endorsed by OETIKER, the clamp is closed by drawing together the lower radii of the “ear”. The maximum diameter
reduction is proportionate to the open “ear” width.
To ensure perfect sealing, clamp ears must be correctly closed during installation.
As a guide, the clamp nominal diameter should be selected so that the outside diameter of the hose, after it has been pushed on to the
component to which it is to be fastened (e.g. a hose nipple), is approximately in the middle of the diameter range of the chosen clamp.
Mechanical Interlock closure
The joining of the band material is a mechanical interlocking design, its purpose is to maintain the integrity of the interrupted strip and
maintain the round geometry. The interlock is designed to withstand the recommended clamp “closing force” for the appropriate material
grade and the anticipated resistance from typical applications. The “resistance load” is closely related to the “closing force”, which is
discussed in Section 3.0. Use of a mechanically jointed band connecting system, as opposed to a spot welding practice, eliminates the potential of induced high temperature corrosion.