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Ermeto Tube Fittings

Ermeto Tube Fittings Chennai

EO-Plus: Progressive Stop Ring PSR for steel fittings

The EO-Plus fitting produces high pressure, leak free connection of tubes and components in fluid systems. The basic function of EO-Plus is the controlled progressive bite of the PSR into the tube due to a unique internal geometry.

The front cutting edge A has already started cutting into the tube before the second cutting edge B begins. As soon as both cutting edges have cut into the tube to the designed depth further advance is limited by the stop shape C and the new overtightening protection D. Additionally, the special form of the PSR with its dimples at the front shoulder section gives an assembly state control.

Owing to the design of both cutting edges and stop shape all forces arising are equally distributed. This distribution along with the specially designed interior collar E of the ring guarantees increased safety, particularly with regard to vibration and flexure stresses. Service vibration loading is not present in the areas of the tubing where the bite is made.

The stop shape as well as the overtightening protection cause a clear sharp increase in tightening forces. After assembly, a visible collar F of cut tube material must completely fill the space in front of the first cutting edge. A slight bowing up of the ring G is desirable. This spring effect provides permanent compensation for flexural vibration and settling effects in the thread of the fitting nuts.

Ermeto Tube Before Tightening & After Tightening

Plus: Spring effect

Thanks to the spring effect, retightening

of the fitting is not necessary. Upon the completion of the assembly (due to the geometry, material and heat treatment) an elastic initial tension is achieved which compensates displacement effects in the thread and at the bite point of the tube.

Plus: Safe assembly

Two distinctive cutting edges

provide a progressive increase of the tightening torque of the PSR. The noticeable end point of assembly contributes to maximum safety of assembly, and the multifunctional ring geometry prevents over-tightening.

Plus: Chromium-free

Due to its chromium6-free

treated surface, Parker Ermeto now meets the expected requirements to be expected in the automotive industry and the requirements issued by the European Parliament to eliminate the use of materials and surfaces containing chromium6. The removal of chromium6 reflects Parker’s ongoing commitment to an environmentally clean and safe production process.

Plus: Increased pressure

Due to the application of even better materials combined with the special processing of individual components, EO-Plus can be used in applications of up to 800 bar (S series) and 500 bar (L series). EO-Plus considerably exceeds the DIN/ ISO requirements and guarantees a 4-fold design factor. Thanks to the higher pressure levels, less expensive “L” series fittings can now be used instead of the heavier “S” series.

Plus: Overtightening protection

The special geometry of the PSR prevents the overassembly of EO-Plus fittings.

Plus: Highest corrosion resistance

The corrosion resistance is increased to more than 500 hours to white rust.

Raccord Haute Pression


As a part of Parker Ermeto’s New Generation fittings, the Dry Technology EO-2 Plus Concept proven worldwide has been further developed. EO2-Plus means maximum pressure capability, as well as a new chromium6-free surface with significantly higher corrosion resistance, and greatly reduced tightening torques for larger sized fittings. The common feature of all EO2-Plus fittings is elastomeric seals on all joints. These are also now available in FKM (e.g. Viton®) for applications with higher temperatures or aggressive media. This assures leak free operation without retightening – even under extreme working conditions. The easy handling, time and cost saving features, and many assembly advantages of the unique EO2-Plus functional nuts have made EO2-Plus fittings increasingly popular.

EO2-Plus is designed for metric tube and based on German Standards DIN 3861 and DIN 2353, which today are represented by the international standard ISO 8434-1. EO2-Plus is available in “L”- and “S”-Series.

Elastomeric sealing

The elastomeric seal assures a hermetically sealed tube joint. It is located in between the inner cone of the fitting body and the tube surface, thus blocking the only possible leak path. Due to its large cross-section, the seal effectively compensates for all manufacturing tolerances on tube and fitting cone. The sealing effect is pressure supported which makes the EO2-Plus fitting suitable for high pressure applications. The static compression also eliminates air-ingress into the fluid system at underpressure conditions. Elastomerically sealed EO2-Plus fittings do not require any retightening even in heavy duty applications. Seal extrusion is prevented by proper housing without gaps or dead volume. The sealing lip is bonded to a metallic support ring.

Assembly “to block”

The retaining ring bites into the tube in accordance to the proven bite ring principle. The support ring reduces the danger of over- or underassembly by a special EO2-Plus design feature: Before assembly there is a gap in between the flat surfaces of the retaining ring and the metallic support ring of the seal. As soon as the retaining ring has reached the proper bite depth, the gap closes, resulting in a sharp increase of assembly torque. This results in uniform and reliable fitting assemblies. The assembly result can easily be inspected by just checking if the gap is closed. The separation of sealing and fixing function to two separate elements finally allows a more effective solution of the over- and untertightening problems of bite type fittings than increasing the number of cutting edges.

Integrated assembly tool

The metallic support ring of the seal is made of a special design, material and heat-treatment to act as a assembly tool. This makes sure that the retaining ring securely cuts into the tube surface without damaging the sensitive inner cone of the fitting body. This unique feature of EO2-Plus fittings even allows direct assembly of stainless steel tube without any additional pre-assembly process. Of cause, an EOMAT machine can be used to allow easy assembly of large dimension tube and drastically save total assembly time, effort and costs. The integrated assembly tool of EO2-Plus fittings even helps to save further costs and trouble when using an EOMAT-type presetting machine: As the presetting cone is only in contact with the elastomeric sealing lip, it cannot be worn out or damaged even after thousands of assemblies. This does not only save replacement costs but also avoids leakage problems caused by worn presetting tools.

The functional nut

The unique functional nut simplifies handling of fitting components and helps to minimise storage and procurement costs. The sealing and retaining rings are combined as a pair and are inserted into the internal thread of the nut in such a manner that they cannot fall out, so that these three parts form one functional element. Individual components such as seals or retaining rings cannot be forgotten, confused or assembled in the wrong orientation. Time and cost is saved, arranging the components to make up individual joints. The functional nuts match all EO tube fitting joints. After assembly and disassembly, the sealing ring can be replaced individually without cutting off the tube end.


EO2-FORM is the new high pressure formed tube Generation of the Tube Fittings Division Europe. As with EO2- Plus, it is designed in to eliminate leakage in all fluid systems, by using elastomeric sealing systems.

The common feature of all EO2-FORM connections are the EO2 seal elements (Dry Technology) as well as the new cold forming process, that gives extreme rigidity and low tightening torques. The seals are now also available in FKM (e.g. Viton®) for applications with higher temperatures or aggressive media.

Through EO2-FORM, elastomeric sealing technology is made available even where bite-type connectors are not popular, like in hydraulic presses, cranes, lifts or ship canal locks. Compared to welding or brazing, the EO2-FORM process is faster and easier. It does not require special tube treatment, heating or chemicals.

EO2-FORM is designed for metric tube and fully interchangeable to the complete Ermeto Original product range according to ISO 8434-1 / DIN 2353. EO2-FORM is available in “L”- and “S”-Series.

System solution

No additional items need to be purchased or stocked on top of the existing EO-2 product range. Assembly characteristics of EO-2 FORM are similar to EO2-Plus, too. Therefore, EO2-FORM can be introduced with minimum effort.

Flexible concept

The product family of EO-2 and EO2-FORM allows the application of the optimum product within a complex hydraulic system or a whole manufacturing facility. EO2-FORM can be used for heavy duty applications like presses, EO-2 is ideal for general hydraulic and pneumatic pipework. This allows maximum total system performance with minimum component, assembly and stocking cost.

No risk

EO2-FORM technology is based on the proven EO-2 technology. All components and the assembly technology are approved. The customer does not have to test a new system.

Sealing capability

The high volume elastomeric seal forms the primary sealing element, thus assuring leakfree sealing. Even low-viscosity media such as water or gas are hermetically sealed. Hydraulic systems therefore do not “sweat” at the fitting joints.

No phantom leaks

Lubrication is not mandatory for the assembly of steel EO weld nipples. The machine operator will not be irritated about lubricant coming out of the fittings once the hydraulic system gets hot


EO2-FORM connections can be disassembled and reassembled many times. There is no wear or widening of the vulnerable fitting inner cone.

Highest pressure performance

Due to the application of even better materials combined with the special processing of individual components, EO2-FORM can be used in applications of up to 800 bar (S series) and 500 bar (L series). EO2-FORM considerably exceeds the DIN/ISO requirements and guarantees a 4-fold design factor. Thanks to the higher pressure levels, less expensive “L” series fittings can now be used instead of the heavier “S” series, which also is a benefit in limited or tight space applications.


Compared to welding or brazing, EO2- FORM is much less time consuming. Special tube preparation and finishing are not necessary. Forming uses only a fraction of the energy needed for brazing or welding.

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Hydraulic Quick Couplings

Hydraulic Quick Couplings

Double Shut-Off and Straight-Thru Couplings

Parker hydraulic couplings have a wide variety of designs, each tailored to a particular application or use. This catalog is arranged according to those categories. In each section the construction of a specific design will be detailed. However, based on the valving of the coupling, hydraulic couplings generally fall into one of two groups, either Double Shut-Off or Straight-Thru. Double Shut-Off couplings are used extensively when it is important to minimize fluid loss upon disconnection. Both halves of the coupler, the body and the nipple, contain shutoff valves. These valves open automatically when the body and nipple are connected, and close automatically when the two halves are disconnected—keeping fluid loss to a minimum. Parker Straight-Thru couplings have no valves in either half and are ideal for maximum flow application. Their smooth, open bore offers the lowest pressure drop of any quick disconnect coupling, and allows them to be thoroughly cleaned. Since there are no valves in either half, fluid flow should be shut off before the coupling is disconnected.

Rated Pressure

Rated pressure for the Parker hydraulic couplings range

from 30 to 15,000 psi, depending on the coupling series, size and materials. Rated pressures as shown in this catalog are defined in the American National Standard Glossary of Terms for Fluid Power, ANSI/B93.2-1986, as “the qualified operating pressures which are recommended for a component or a system by the manufacturer.” Parker “Rated Pressures” have been established on the basis of laboratory tests which include, but are not limited to, static burst tests and multiple cycle impulse tests. System characteristics such as high cycling rates and high amplitude shocks either hydraulic or mechanical, can reduce the functioning life of a coupling, even if the system’s nominal pressure falls within the rated pressure range of the coupling.

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