PetroStreet

Salam,

Any guidelines available for insulation design for expansion joints? Reference to standards would help .

Kamran

Are you talking about the expansion bellows?
See the figures attached that may help you through.

Thanks for the clarification and apologies for the late response.

1)Where in process piping (typical application) where we prefer Expansion joints over expansion loops?

2) Which type of Expansion Joints are most commonly used in process Industry & why?

3) Generally Expansion loops are mostly used as compared to expansion joints , Why is it so.?

4) What is the cost comparison of Expansion joints vs expansion loops ?

Regards

1- According to my knowledge, expansion joints are only preferred in process piping when you have space limitations for expansion loops. Otherwise, I have always seen expansion loops being provided by most of the piping designers.

2- Most commonly used types of expansion joints in process piping are metallic bellows, rubber bellows, ball and slip (mechanical coupling type).

3- The main reason behind this is to have hazard free and maintenance free operation with expansion loops. Expansion joints have their maintenance to be made, fixed life span, corrosion problems, spares to be made available for any quick repair etc. Expansion loop once installed properly would not demand anything; providing unlimited maintenance free operation.

4- Normally, expansion joints are made available in lesser cost than providing expansion loops as additional elbows, pipes, welding, inspection works for expansion loop make it a costly choice. But on the long run what I have explained in point (3), maintenance free operation will return you the initial cost invested for expansion loops.

I would go for providing expansion loops instead of expansion joints to avoid maintenance, fixed life cycle, specific inspection plans. But yes where there is a limitation of providing expansion loops, no other option left else to select the applicable expansion joint.