ELAFLEX. PREMIUM-QUALITY RUBBER EXPANSION BELLOWS
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On all stock items ordered.
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Design & Manufacturing
Full in-house design & manufacture to EN / ASME / PED.
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FlexEJ has an accredited Environmental Management System.
Elaflex Rotex DoubleRed Rubber Bellows
The Elaflex Rotex DoubleRed rubber bellows features an EPDM, hot water resistant, seamless, high abrasion resistance liner with Polymer textile cord, hot water and hydrolysis proof reinforcement and EPDM, ozone proof, heat resistant cover.Â
Untied
Tied Outer
Tied Outer
Tied Angular
The Rotex DoubleRed is suitable for hot heating water, cooling water and hot air. Approved to DIN 4809. The Rotex DoubleRed is available from DN25 to DN1000 with a wide choice of configuration, flange and restraint options:
PRODUCT GUIDES
ELAFLEX RUBBER BELLOWS
WHAT IS AN ELAFLEX ROTEX DOUBLE-RED RUBBER BELLOW?
DESIGNED FOR HIGH TEMPERATURE WATER SERVICE…
Materials
EPDM for high temperature, swivel flanges as standard in zinc plated carbon steel.
Application
DIN4809 design for high temperature water services, not suitable for drinking water, mineral oils.
Rating
PN16 to DN400, PN10 to DN1000 -40°C up to +130°C, temporarily up to +150°C. Electrically dissipative.
WEB SHOP
Available online with next day delivery from our web shop.
ELAFLEX ROTEX DOUBLERED RUBBER BELLOWS
| SIZE | LENGTH | PRESSURE RATING | MOVEMENT | IN SHOP |
|---|---|---|---|---|
| DN25-1″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | |
| DN32-1¼” | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | Yes |
| DN40-1½” | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | Yes |
| DN50-2″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | Yes |
| DN65-2½” | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | Yes |
| DN80-3″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 30º | Yes |
| DN100-4″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | Yes |
| DN125-5″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | Yes |
| DN150-6″ | 130mm | 16 Barg @ 50 ºC to 10 Barg @ 100 ºC | Axial +20/-30 mm, Lateral +/- 30 mm, Angular +/- 20º | Yes |
| 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 a Rotex DoubleRed Rubber Bellow
Temperature is the most critical as it directly influences the choice of rubber – but also the actual pressure capability of the bellows. The stated maximum rated pressure is maintained up to around 50ºC for most rubber bellows, for higher temperatures check the data in the Range tab.
Elaflex Rotex DoubleRed Restraint options
FlexEJ has the following tie rod restraint options in stock for the Rotex DoubleRed Rubber Bellows range. Angular and more advanced configurations can be engineered to your exact requirements, however complex. Just let us know what you have in mind.
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 /expansion-bellows/ 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 /expansion-bellows/, 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 /expansion-bellows/. 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 /expansion-bellows/ 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.Elaflex Rotex Finders and Calculators
We have a couple of easy to use tools and calculators to help you look up the best Rotex DoubleRed ERP rubber bellows from our next-day delivery stock items. Our Thermal Expansion Calculator for Piping helps you estimate the increase in length of a pipe run with temperature. Our Advanced Bellows Finder is another quick way to browse and compare all our stock expansion bellows and joints. With just a few choices you can arrive at the appropriate selection – criteria include pipe size, type, media compatibility, installation length, pressure rating, pipe connection type, conformance and movement axial, lateral and angular. All the products are in the online store with 24hr shipping as standard. If you’re not sure what flange you need, our handy Flange Finder should also be useful.
Stock Rotex Rubber Bellows Finder
Do search for Elaflex Rotex expansion bellows by pipe size, intended media and/or connection hardware to see FlexEJ’s stock Rotex bellows options below but don’t hesitate to call us on 01384 881188 or email us for more bespoke options, sizes and restraint configurations or technical advice.
Can't quite find the right bellow?
Try our Advanced Bellows Finder
Or call our expert team on +44 (0) 1384 881188. We'll be glad to help.
Rotex DoubleRed Comparison Chart
Is the Rotex DoubleRed 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?
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
Frequently Asked Questions
A. Yes. FlexEJ holds a large stock of the most popular sizes and types of Elaflex rubber bellows as well as our HVAC value bellows range. We also hold stock of the most popular metal bellows for HVAC. Many of these items are available on 24hr delivery from our online web shop. We can also manufacture to order. For sales assistance please contact us or use our Live Chat facility.
A. Our Flange Finder contains details for many common flanges. Typically, to be able to make the identification you need to know the bore size or outside diameter and number of bolts. For technical assistance contact us or use our Live Chat facility.
A. Please refer to our guidelines for installation, anchoring & guides. They are available in the Downloads section of this website: Elaflex Rubber Bellows Installation Instructions and FlexEJ Metal Bellows Installation Instructions. For technical assistance please contact us or use our Live Chat facility.
A. Yes, our Elaflex ERV-R and ERP rubber bellows have WRAS, DVGW and ACS approval for drinking water. The Safetech manufactured to order rubber bellows can be supplied with WRAS approved EPDM linings. Our MRCA copper ended metal expansion joints also have WRAS approval. For technical assistance please contact us or use the LIVE CHAT link on this page.
A. The ERP Redspot, ERV-R Redband and Rotex DoubleRed bellows are now available from FLEXEJDIRECT from stock for the most common sizes and configuration of these popular high-quality bellows. The shop items and can be despatched same day (Monday to Thursday) on a 24hr service if in stock. More advanced configurations and the other nine Elaflex bellows ranges are available to assemble to exact specifications and typically take 7-10 days (depending on size, quantities and configurations required).
Please visit our full FAQ page to see all our frequently asked questions.