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Does fatigue failure of an expansion joint include the natural vibration of the structure and the natural frequency of the piping system during operation?

We do not include the vibration calculations in the normal design calculations, however, if you provide the natural frequency of ...Continue Reading

Does air between multilayer expansion joints reduce the pressure rating from single thickness?

Can you explain how carbon steel does not have sufficient elasticity?

Compared to stainless steel, carbon steel has modulus of elasticity at a higher temperature

Can expansion joints be repaired in the field?

We can send technicians to the field for certain repairs, however, it depends on the extent of the repair.

Can double gimbal expansion joints be self-stable if applied horizontally?

Yes, the gimbal hardware of a gimbal expansion joint can be designed to support the weight of adjacent piping.

Are you carrying out finite element analysis for designing the bellows?

Yes we are able to perform finite element analysis for bellows design. Normal bellows design is based on EJMA equations.

Are there special considerations for bellows material that do not have a fatigue endurance limit such as titanium?

We do not make bellows out of titanium but every material has their fatigue cycle. Titanium has higher stress allow-ables ...Continue Reading

Are there expansion joints for seismic joints?

Are hinged pipe expansion joints provided with pin holes?

Some hinge types can be provided with hinge pin holes which are slotted to permit limited axial travel. These slotted ...Continue Reading

Why is necessary to eliminate excessive flexibility?

Excessive flexibility increases material costs, increases pressure drops, increase vibration, and creates 2-phase flow occurrences.

How are failures due to inadequate flexibility now almost nonexistent?

Increase in the number of segments (nodes) reviewed though computer use and use of precise calculations.

What are individual Stress-Intensification Factors (SIF) applied for?

Welds, fittings, branch connections , and other piping components where the possibility of fatigue failure could occur.

What is the Stress-Intensification Factor?

The Stress-Intensification Factor is the ratio of the maximum stress intensity compared to the nominal stress.

What does the Maximum Shear Stress Theory state?

The maximum shear stress theory states that failure of a piping component occurs when the maximum shear stress exceeds the ...Continue Reading

Out of the Six Theories of Failure, which are the 2 that are the most widely used?

What does the Maximum Principle Stress Theory state?

This theory states that yielding in a piping component occurs when the magnitude of any of the three mutually perpendicular ...Continue Reading

What are the 5 modes of failure of piping design?

Failure by general yielding, yielding at sub-elevated temperature, brittle fractures, and fatigue.

What is the purpose of Stress Analysis?

Stress analysis ensures the safety of piping and piping components, safety of connected equipment and supporting structure, and that piping ...Continue Reading

What is Stress Analysis?

A term applied to calculations, which address the static and dynamic loading, resulting from the effects of gravity, temperature changes, ...Continue Reading

What is the Stress-Strain curve?

It is a visual representation of the effects of various loading conditions on a piping system between stress and strain.

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