Elaflex - Excellence in Rubber Bellows
Manufactured in Germany these high quality, durable rubber bellows have thousands of configuration options.

Elaflex BlackBand ERV-CR Rubber Bellows
The Elaflex BlackBand ERV-CR rubber bellow features a Chloroprene CR, seamless, abrasion resistant liner with PA textile cord reinforcement and Chloroprene CR cover. Suitable for cold and warm water, swimming pool water, sea water, waste water (weakly sour or alkaline), water containing oil, cooling water with oily additives, lubricating oil, grease and air and compressed air. The BlackBand ERV-CR is available from DN25 to DN1000 with a wide choice of configuration, flange and restraint options:
Elaflex Rubber Bellows
What is an Elaflex ERV-CR Rubber Bellows?
Versatile choice for water, weak chemicals, oils...
- Materials
Chloroprene CR, swivel flanges as standard in zinc plated carbon steel - Application
Water services including contaminated / oily, oils, greases, compressed air, not suitable for drinking water - Rating
PN16 to DN400, PN10 to DN1000 -40°C up to +90°C, temporarily up to +100°C. Electrically non conductive. - Approvals
DNV / BV / CCS
Elaflex BlackBand ERV-CR rubber bellows
Size | Length | Pressure Rating | Movement | In Shop |
---|---|---|---|---|
DN025-1" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN032-1¼" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN040-1½" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN050-2" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN065-2½" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN080-3" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
DN100-4" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | |
DN125-5" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | |
DN150-6" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | |
DN200-8" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +30/-25 mm, Lateral +/- 30 mm, Angular +/- 10º | |
DN250-10" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +30/-10 mm, Lateral +/- 15 mm, Angular +/- 5º | |
DN300-12" | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +30/-10 mm, Lateral +/- 15 mm, Angular +/- 5º | |
DN350-14" | 200mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 30 mm, Angular +/- 8º | |
DN400-16" | 200mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 30 mm, Angular +/- 8º | |
DN450-18" | 200mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 30 mm, Angular +/- 8º | |
DN450-18" | 250mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 35 mm, Angular +/- 10º | |
DN500-20" | 200mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 30 mm, Angular +/- 8º | |
DN600-24" | 200mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 30 mm, Angular +/- 8º | |
DN700-28" | 260mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +30/-40 mm, Lateral +/- 30 mm, Angular +/- 5º | |
DN800-32" | 250mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +35/-40 mm, Lateral +/- 35 mm, Angular +/- 5º | |
DN900-36" | 300mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +40/-40 mm, Lateral +/- 40 mm, Angular +/- 5º | |
DN1000-40" | 300mm | 10 Barg @ 50 ºC to 6 Barg @ 100 ºC | Axial +40/-40 mm, Lateral +/- 40 mm, Angular +/- 5º | |
How to select an Elaflex rubber bellows






Can't see what you want? Need help?
Call us. Or use Live Chat.
For instant advice. We can custom-design and engineer almost any expansion joint you need for delivery in the UK or worldwide. Call our expert team on +44 (0) 1384 881188. Or email us sales@flexej.co.uk
BlackBand ERV-CR standard restraint options:
FlexEJ has tie rod restraint options in stock for the BlackBand ERV-CR bellows range. Angular and other configurations can be engineered to your exact requirements, however complex:
Without Restraints
(Untied)
WITHOUT RESTRAINTS
No movement restriction, pressure force acts on pipe
The bellows will exert a pressure force on the pipe (see FAQ) as the bellows tries to elongate which must be absorbed at the piping anchors. Any equipment connected to the bellows must have an adequate flange load rating.
Tie rods with outer nuts
(Tied)
TIE RODS WITH OUTER NUTS
No axial extension, pressure force restrained
Tie rods with outer nuts only restrict the elongation of the bellows under pressure and restrains the pressure force. Up to DN300 the tie bars lie elastically in noise-reducing rubber bushes of weatherproof rubber, from DN350 steel spherical washers are provided. The bellows can move laterally. Axial compression is also possible but only if the piping overcomes the pressure force.
Tie rods with inner and outer nuts
(Lateral only)
TIE RODS WITH INNER AND OUTER NUTS
No axial extension or compression, pressure force restrained
Tie rods with inner and outer nuts both restrict the elongation of the bellows under pressure (restrains the pressure force) and limits axial compression. Up to DN300 the tie bars lie elastically in noise-reducing rubber bushes of weatherproof rubber, from DN350 steel spherical washers are provided. The bellows can move laterally. Axial compression is also possible but only if the piping overcomes the pressure force and a gap is set between the inner nuts and the flange.
Hinges
(Angular only)
HINGES
Angular movement only, pressure force restrained
The hinge restricts bellows movement to angular only. The pressure force is restrained by the hinge. No axial or lateral movement is possible. Two hinged bellows working together can form a very effective restrained lateral joint with low spring rate capable of very large movements.
Got a quick question?
Use Live Chat. Or call us.
For instant advice use the Live Chat link to message one of the sales team. Or call them direct on +44 (0) 1384 881188
BlackBand ERV-CR comparison chart
Is the BlackBand ERV-CR the best option for your application? Three potential alternatives to consider:
WRAS approved WRAS approved bellows
Is this bellow approved for use in all UK public mains water supplies?
Potable water Potable water
Is this bellow approved for water systems used for drinking and food preparation?
DIN 4809 compliant HT Heating Water DIN4809 compliant
Is this bellow compliant with the German DIN4809 standard of approval for warm water heating systems? (Max 100°C, 10 bar).
Oily & drainage water Oily & drainage water
Contaminated, oily, drain & waste water. Is this bellows suitable for contaminated water services that would degrade an EPDM rubber?
Rating barg/°C Pressure & temperature
What is the required pressure rating (in barg) compared to temperature rating for this bellow?
Not sure what flange spec you need?
Use the FlexEJ Flange Finder to find out
FlexEJ stock a full range of specs and types for our bellows. Or call our expert team on +44 (0) 1384 881188.
Who can you talk to?
Try our sales and customer service team on 01384 881188
They don't bite. And they know what they're talking about. Call the team any time from 9am to 4pm weekdays or use LIVE CHAT if you would prefer a quick text answer. For more complex queries, send us any pro-forma documentation using the get a quote form below or email us sales@flexej.co.uk.
Can't quite find the right bellow?
Try the FlexEJ Bellows Finder
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Frequently Asked Questions
Please visit our full FAQ page to see all our frequently asked questions.
Need a detailed quote?
Get A Quote. On us.
We will provide full technical details together with, pricing and shipping timescales. For more complex engineered quotes, preliminary sketches and calculations will be available.
Got a quick question?
Use Live Chat. Or call us.
For instant advice use the Live Chat link to message one of the sales team. Or call them direct on +44 (0) 1384 881188
Get A Quote
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Alternatively, you can also call our expert team directly on +44 (0) 1384 881 118 from 8:30AM to 4:30PM weekdays who will be only too pleased to talk through your requirements and technical queries over the phone.
Visitors are also welcome Monday to Friday although please get in touch beforehand to let us know you're coming.
Industry experience
FLEXEJ Ltd was formed in 2002 by two professional engineers who brought together an already highly respected design capability with business and commercial skills gained in large multinational companies.
- Our focus has always been on application and design – helping our customers find the best value solution.
- We have a strong engineering and manufacturing team with experience in petrochemicals, refining, nuclear, desalination though to HVAC.
- The team is also very familiar with meeting complex requirements for documentation, in process NDT and test on projects. We have supplied many large end-users such as EDF, Exxon, Shell, Reliance & QatarGas working with major contractors such as JGC, Foster Wheeler & Technip.
