Union End Metal Bellows
FlexEJ union-end HVAC axial compression expansion joints come with a BSP union swivel at both ends complete with fibre washer and stainless steel convoluted bellows from DN15 (15mm) to DN50 (50mm):
HVACUnion End
HVACUnion End
HVACUnion End
HVACUnion End
HVACUnion End
HVACUnion End
Union End Metal Bellows
What is a Union End Metal Bellow?
BSP female unions for threaded connections and axial compression..
- Materials
Stainless steel 316 bellows with iron BSP unions. - Application
Heating water and most water services, not suitable for drinking water. - Rating
6 Barg @ 150°C. - Web Shop
Available online with next day delivery from our web shop.
How to specify a metal expansion joint
We design and manufacture metal expansion joints so you are not restricted to our range of standard products, some of which are available in our web shop. For simpler applications a standard product may be entirely suitable but if not we will design to meet your exact requirements.
Metal bellows have a defined fatigue life based on movement cycles. Understanding the movements, if they are concurrent or not and the realistic number of times the movements can occur is fundamental to metal bellows design.
Metal bellows work well up to around 500ºC, above that we use insulation to control the actual bellows metal temperature if the media is above this temperature. Pressure and temperature must be known to select a metal expansion joint.
The most common material used for metal bellows is Stainless Steel - 304, 321, 316 - and for more demanding applications Nickel Alloys - 625, 800, 825. Corrosion is the most likely failure mode for the bellows itself so the correct material selection is important.
Our standard ranges have set lengths for each diameter / movement range but we can design to meet your exact requirements. Making the bellows longer will increase the available movement. Most commonly a flange, we can provide to any specification, or pipe weld ends. Our HVAC standard product is available with BSP Union ends and Copper Pipe ends. If you are uncertain about what flange type you already have installed our Flange Finder will help you identify it.
Call our expert team on +44 (0) 1384 881188 or email us at sales@flexej.co.uk or use Live Chat on this web site - we are here to help, please get in touch.
FlexEJ's Union End Metal Bellows
For use on threaded connections and axial compression
| 316 stainless steel bellows | Threaded female BSP |
| Iron swivel unions | Rated 6 Barg @ 150°C |
| Minimum length design | For axial compression |
Specifications
All sizes available from our web shop
For ratings and dimensions please see our catalogue or range tab above.
HVAC Union End Metal Bellows Product Comparison Chart
Is the HVAC Union End metal bellows the best option for your application? Two 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?
Rating barg/°C Pressure & temperature
What is the required pressure rating (in barg) compared to temperature rating for this bellow?
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.
