Cold Wall Expansion Joints

Features to look for in Cold Wall Expansion Joints Designed for FCC and other High Temperature Services

With Senior Flexonics Pathway’s Cold Shell Design, The Refractory Cools The Pipe Wall So That Low Alloy Or Carbon Steel Materials May Be Used For The Shell To Reduce Cost. The Bellows Operates In A Low Temperature Range Where The Bellows Materials Have The Greatest Strength And Best Performance Characteristics.

1. INTERNAL KAOWOOL BLANKETS The internal kaowool blankets provide excellent insulation properties and prevent immobilization of the bellows due to packing of particulate from the media.

2. EXTERNAL KAOWOOL BLANKET The external kaowool blanket ensures a uniform temperature across the bellows while maintaining the bellows at a temperature above the dew point of the media. In many applications, the media can aggressively attack the bellows if the dew point is reached during operation. Stabilization of the bellows temperature reduces the possibility of thermal shock and thermal distortion of the bellows. This blanket is wrapped in a wire mesh to protect the kaowool during operation and during removal for inspection.

3. WOVEN WIRE MESH SEAL The woven wire mesh seal is a tough, knitted wire product which has proven to be much tougher and more resilient than hose braid that is often specifi ed as a liner seal material. The woven wire mesh seal retains the internal kaowool blankets while keeping out large particles from the media.

4. KAOWOOL PACKED CAVITY TO INTERRUPT RADIANT HEAT This kaowool packed cavity is superior to refractory due to the higher insulating value of the kaowool. This cavity eliminates the direct radiant heat path to the shell while providing a smooth sliding surface for the woven wire mesh. The downstream ring defi ning the cavity is designed with a small gap on the outside diameter to allow for radial growth without buckling or warping. The gap also interrupts the heat path to the shell.

5. LINER TRANSITION The sloped liner transition minimizes the thermal stresses. The expanded end confi guration also eliminates one circumferential weld from the alternate welded conic design.

6. REFRACTORY WITH ANCHORS The confi guration of the expansion joint allows the refractory to form a smooth full bore liner which reduces the turbulence of the media. A minimum of two inch refractory thickness is recommended on the liner to ensure integrity of the refractory.

7. COVER The cover provides mechanical protection from external weather conditions or foreign objects and gives additional protection to personnel in the event of an emergency.