Special Expansion Joints


Bellows of special expansion joints are designed according to EJMA code. For high pressure applications multi layered bellows also bellows with reinforcing and equalizing rings are possible.

According to the requested features like type of transported media, spring rate values (axial, lateral, angular) and operation temperature and pressure also life cycle bellows material could be customized.


Expansion Joints are the parts of pip­ing system of pressurized equip­ment. In this respect construction of the expansion joints are designed and produced according to European pressurized equipment directive (PED 2014/68/EU) as well as American Nation­al Standard for piping process ASME Section VIII Div. 1&2, ASME B 31.3.

All components of the expansion joints like, pipes, caps, flanges, tie rods etc… are checked by piping stress ana­lysis thus enable us to se­lect material type & thickness accord­ing to permissible stress values.


General Capability Range for Ayvaz Special Expansion Joints

Up to 150 bar (depending on the diameter and temperature)
Design temperature (Material selection)
Lifting capacity

PED 2014/68/EU&ASME U Stamp-U2 Stamp

Expansion Joints are the parts of piping system of pressurized equipment in this respect construction of the expansion joints are designed and produced according to PED 2014/68/EU&ASME U Stamp-U2 Stamp.

Production Tests

• Hydrostatic Pressure: Expansion joints are exposed to hydrostatic pressure at 1,5 times of design pressure.

• Vacuum Test: For full vacuum applications, vacuum test at 760 Hg/mm is also applicable.

• Gas Leakage Detection: Additionally, gas leakage detection with helium is advised for proper tightness.


All welding operations for the construction of expansion joints are completed according to European norms or ASME standards optionally.

• WPS are issued acc.to EN 15609-1
• PQR are issued acc.to EN 15614-1
• Welders Certificate EN ISO 9606-1
• Welding Operators EN ISO 14732
• ASME Section IX

NDT Controls

Non-destructive testing for welding controls are completed in house by the TÜV accredited third party inspectors. Following controls and standards are applicable.

• 100%PT acc.to EN3452-1, EN23277
• 100% MT acc.to EN17638,
• 100%VT for Fillet welds
• 100%RT acc.to EN ISO 10675-1, EN I7636
• 100%UT acc. to EN 17640, EN 11666

Inquiry Form

Please send us your inquiry using our contact form and we will contact you immediately. Inquiry Form