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We do not include the vibration calculations in the normal design calculations, however, if you provide the natural frequency of the vibration, we can consider it.

There will be reduction of the pressure capacity of the bellows.

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

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

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

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

We do not make bellows out of titanium but every material has their fatigue cycle. Titanium has higher stress allow-ables at temperatures but it does not mean they have infinite cycle life.

Yes there are and US Bellows, Inc. can design and manufacture these.

Some hinge types can be provided with hinge pin holes which are slotted to permit limited axial travel. These slotted hinge types will not resist pressure thrust forces, and anchoring must be provided.

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

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

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

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

The maximum shear stress theory states that failure of a piping component occurs when the maximum shear stress exceeds the shear stress at the yield point in a tensile test.

The Maximum Principle Stress Theory and Maximum Shear Stress Theory

This theory states that yielding in a piping component occurs when the magnitude of any of the three mutually perpendicular principal stresses exceeds the yield strength of the material.

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

Stress analysis ensures the safety of piping and piping components, safety of connected equipment and supporting structure, and that piping deflections are within limits.

A term applied to calculations, which address the static and dynamic loading, resulting from the effects of gravity, temperature changes, internal pressures, fluid flow, seismic activity, and any external loads.

What is Stress Analysis?

September 11, 2015

A term applied to calculations, which address the static and dynamic loading, resulting from the effects of gravity, temperature changes, internal pressures, fluid flow, seismic activity, and any external loads.

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