General Information About the EO Progressive Ring Fitting
The EO Progressive Ring Fitting creates a leak-free connection between pipelines and components in hydraulic systems. The secure sealing and holding function is achieved by the EO Progressive Ring, which, due to its special geometry, penetrates the tube up to a structurally defined limit during assembly. The progressive penetration of the ring is characterized by the fact that during assembly, the front cutting edge (A) has already begun to penetrate the tube before the second cutting edge (B) engages. When the functionally intended cut for both cutting edges is reached, further advancement is limited.
Due to the geometry of the two cutting edges, applied forces are favorably transferred over the entire cone length in terms of strength. This distribution of forces and the specially designed inner contour at the collar end (C) of the ring result in increased safety under bending fatigue stress. Vibrations are thereby already damped upon entering the ring. The special inner contour causes an increase in tightening forces during assembly up to a noticeable solid point (assembly fixed point). After completion of the assembly, the visible collar bulge (D) must fill the space in front of the first cutting edge. For tubes made of stainless steels and hose nipples made of free-machining steels, the collar bulge is smaller due to the material properties. A slight rebound of the ring (E) is desired. This spring effect permanently compensates for bending vibrations and the setting behavior in the thread of the union nut.
EO-DUR stainless steel fittings are equipped with a special progressive ring whose geometry is optimized for safe assembly with stainless steel tubing. Fittings of the LL series and all brass fittings are equipped with the D cutting and wedge ring.
1 Tube Cut
The tube cut ensures the secure holding function and the leak-free seal. A visible material collar bulge is created, which can be checked by simple visual inspection.
2 Unique Tube Clamping
The tube is clamped in the rear area of the EO cutting ring. Mechanical vibrations are effectively dampened and kept away from the tube cut.
3 Spring Effect
Due to the material, the special heat treatment, and the design of the stainless steel cutting ring, a defined elastic preload is achieved at the end of assembly. This spring effect permanently compensates for bending vibrations and the setting behavior in the thread of the union nut. Ermeto stainless steel cutting ring fittings therefore remain permanently leak-tight even without retightening.
The EO-DUR Stainless Steel Series with Silver-Plated Internal Thread
The tightening torques of the EO-DUR stainless steel nuts are reduced by up to 40 percent due to surface refinement. In addition, cold welding of the stainless steel material in the thread, which would make non-destructive disassembly of the fitting impossible, is prevented. All nuts from size 12S/15L are supplied with a silver-plated internal thread; the smaller sizes receive a special wax coating.
The EO-DUR Suparcased SPH Cutting Ring
The Suparcased cutting ring was developed based on the existing stainless steel cutting ring for particularly aggressive internal and external media. The special geometry and the thermochemical hardening process ensure a permanently tight and corrosion-resistant connection even under the most extreme conditions. Typical areas of application are found in the food and chemical industries as well as in medical technology and mechanical engineering.
On-Site Assembly
EO Progressive Ring Fittings can be assembled anywhere using two wrenches. Simple tools allow the manual assembly of stainless steel tubing.
Cost-Efficient Assembly
Pre-assembly with EOMAT machines is the most cost-effective method for fitting assembly.
Series
Very light (LL), light (L), and heavy (S) can be selected. For every application, there is an optimal solution in terms of: best flow characteristics, sufficient pressure resistance, small installation dimensions, low assembly force, and low costs.
Available Dimensions
Most EO fittings are available in 25 sizes from 4 to 42 mm tube outer diameter. A wide range of reductions allows the optimal dimensioning of every single pipeline. This saves space as well as material and assembly costs.
Tube Wall Thickness
EO fittings are suitable for thin-walled, thick-walled, and extremely thick-walled tubes. Particularly thin-walled tubes can be assembled with the help of reinforcement sleeves (VH).
Tube Materials
EO fittings are suitable for all common tube materials such as steel, stainless steel, copper, aluminum, or CuNiFe. Even plastic tubes made of materials such as polyamide, polyurethane, polyvinyl chloride (PVC), or polytetrafluoroethylene (PTFE) can be processed with insert sleeves.
Visible Collar Bulge
The material bulge in front of the ring cut, which is necessary for safe function, can be checked by simple visual inspection.
Reduced Tightening Torques
EO union nuts are coated with a particularly effective lubricant. The reduced assembly forces help to prevent dangerous under-assembly.
Sealing Capability
EO fittings have demonstrated their performance in applications as diverse as high-vacuum sealing against small-molecule gases up to high-pressure hydraulics.
Vibration Damping
The tube is firmly clamped in the fitting during assembly. This achieves high fatigue strength even under dynamic stress.
Installation Dimensions
Despite their high robustness, EO fittings are significantly smaller than other fitting technologies. This allows for compact piping in confined spaces.
Wide Temperature Range
EO fittings are suitable for use at extremely low to extremely high temperatures. The temperature resistance of the selected material is decisive.
Media Compatibility
EO fittings and seals are available in various materials. This allows almost all media and ambient conditions to be covered.
Manufacturing
EO fittings are manufactured under high-quality requirements. All production sites are audited by various approval societies from shipbuilding, military, and gas technology, and by major customers. The quality management system is certified according to ISO 9001.
EO-DUR
The threads of the stainless steel union nuts are coated with a sliding film. The most effective feature of the EO-DUR union nuts is the silver-plated internal threads (dimensions 15-L–42-L, 12-S–38-S). EO-DUR coated stainless steel fittings do not tend to seize the threads during assembly and require approximately 40 percent lower assembly forces than uncoated stainless steel fittings. The EO-DUR coating increases the speed and reliability of stainless steel piping.
Tube Length Determination
The exact length of tubes can be easily determined and checked. This makes on-site piping particularly simple.
Broad Program
EO fittings are available in more than 50 types. The selection of direction-adjustable fittings is particularly large. This allows for compact piping without the cumbersome combination of unnecessary fittings.
Functional Fittings
EO swivels, check valves, shut-off valves, and measuring ports can be used directly in the piping without additional adapters. This saves not only costs for additional fittings but also space requirements, assembly time, and potential leak paths.
Metric Dimensions
Threads, wrench flats, through bores, and other dimensions comply with metric standards.
Smooth Transitions
All through bores are adapted to the flow cross-sections of the corresponding tubes. LL and L series are designed for use with thin-walled tubes. This achieves the best system performance without excessive noise or heat generation.
Worldwide Popularity
EO tube fittings are accepted worldwide. Most European, Asian, African, and South American standards are strictly metric. However, EO cutting ring fittings are also gaining importance in Australia and North America due to increasing metrication and numerous customer specifications. Many machine operators prefer fitting systems that can be assembled without special tools.