Rubber, fabric and PTFE expansion joints

Technical Features

ERV expansion joints are manufactured with a production program covering the range ND 25 - ND 1000, using "Modelling" automatic process that assures high and constant quality standard.
Several types of rubber materials are foreseen to cover porper application with wide range of conveyed fluids.
Different rubber types are identified with clearly recognizable coloured band.
All ERV expansion joints, indipendantly from ND and rubber type, are reinforced with layers of nylon ropes, diagonally braided in order to obtain a carcass having an axceptional resistance to stresses due to movements and pressure.
Steel wires replace nylon ropes injoints type ERV/Rotex.
From ND 65 up the joints flared edges are reinforced with a steel ring.
The connecting flanges are made up in solid one piece steel and important feature, are interchangeable.
The connecting flanges are properly machined in order to match accurately with the flared adges of the joints.
This solution assures perfect tightness also with high internal pressure.
Additional gaskets are not needed, if counterflanges are smooth, evenly machined and without sharp edges. Upon request, types of joints different from those in standard production can be supplied (angular or universal expansion joints, limit rods, fire protection, etc.)

Typical Services

ERV EXPANSION JOINTS are very flexible and can absorb movements in every directions.
ERV expansion joints solve several problems that are typical in pipelines and connected equipment movement (i.e. stocking reservoirs), rolling, misalignment, unproper erection;
Damping of vibrations due to pumps, compressor and similar equipments;
noise reduction;
damping of water hammer;
dismoutling joints (i.e. for valves);
cut off of the metallic continuity in pipelines and protection against stray currents;
compensation of thermal expansion and damping of vibrations in water pipes on ships and vessels (ERV joints are approved by Lloyd's Register of Shipping and by Bureau Veritas).


Inner tube and outer layer in rubber EPDM (ethylene and propylene polymer).
Temperature range: -30°C to +90°C.
Higly recommended for hot water in heating and air-conditioning system. Resistant o chemical addictives normally used in water-treatment equipment and to antifreeze product.
Also suitable for sea water and alcohols, ammonia, hydrogen dyoxide, some acid and bases, compressed air conveyng small quantity of lubricating oil (alternative is ERV/N).
Recommended for drinking water,oils and petroleum refining products.


Inner tube and outer layer in rubber EPDM (ethylene and propylene polymer).
Temperature range: -30°C to +110°C
Insertion of layer of polymer textile cord. The polymer textile layers give to ERV/Rotex joint superior resistance where endurance at contiunos high temperature is a requirement.
Especially recommended in heating system where continuos working temperature can reach 110 °C with temporary values of 130 °C.
TUV approved for 10 years endurance.
Not suitable for drinking water, oils and petroleum refining products.


Inner tube in rubber NBR (acrylonitrile).
Outer layer in rubber CR (Chloroprene)
Temperature range between: -30°C to +90°C.
Especially suitable for oil, greases, flues with hydrocarbon content up to 50%, materials in granules and dust either dried or aqueos solutions: recommended for compressed air with high of lubrificating oil.


Inner tube and outer layer in Hypalon®
Temperature range: between: -30°C to +80°C.
Recommended for acids, alkalies and wide range of chemical products.


Inner tube of white rubber NBR (acrylonitrile type suitable to foods suff industry quality standards).
Temperature range: between -30°C to +80°C.
Designed for edible fluids like drinking water, beer, wine, vegetables oil, fats, fluids containing CO2 and other fluids requiring sanitary rubber compound which does not impair taste.