Insider Secrets of Bellows Repair

Insider Secrets To Expansion Joint Repair

July 9, 2014

Proceed with care I guess I should give the obligatory warning statement about how weld repairing bellows is specialized: it should only be attempted by professionals, don’t run with scissors, yadda, yadda. All true, but we both know end-users will, can, and have weld repaired thin gauge bellows, some with success and some with consequential

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Westinghouse Tap Caps

Westinghouse Tap Caps

October 10, 2017

Westinghouse Cross-Over Expansion Joint Alert Prevent Manage failure of the inner bellows ply It has already failed; you just don’t know it yet Stop what you are doing right now and go check your Westinghouse steam turbine cross-over expansion joint 2-ply bellows test ports to make sure they are not capped. Go ahead; I’ll wait.

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Why An Expansion Joint Works Part One

Why An Expansion Joint Works Part One

August 1, 2014

How does a thin bellows hold the same pressure as that of a thicker pipe? The hoop stress pressure of a pipe is derived and then a comparison is made to how it is calculated for a metal bellows. This is the basis for the equation found in both the ASME code and the EJMA

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Why An Expansion Joint Works Part Two

Why An Expansion Joint Works Part Two

August 1, 2014
How does a metal bellows flex? The theory of bellows deflections are discussed along with the EJMA (expansion joint manufacturers association) fatigue curves. A brief review is given as to how the EJMA fatigue curves were developed. A comparison is made between the deflection of a metal bellows verses that of a pipe loop for Read More
Metal Expansion Joint Installation

Metal Expansion Joint Installation

August 1, 2014
Guidelines are given for the correct installation steps for metal expansion joints. This is a video that is of interest to pipe fitters and maintenance engineers. Length: 5:21 Read More
2-Ply Testable Bellows For Steam Turbines

2-Ply Testable Bellows

August 1, 2014

Many users such as power plants and refineries have expansion joints with 2-ply testable bellows. These redundant bellows are often overlooked during the piping system inspection. A demonstration is provided with a recommended test fixture for safe and easy testing between the bellows plies. This is a video that is of interest to maintenance engineers

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Steam Extraction Expansion Joints

Steam Extraction Expansion Joints

August 1, 2014

There is no excerpt because this is a protected post.

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Understanding Bellows Internal Pressure

Understanding Bellows Internal Pressure

July 12, 2014

Understanding Bellows Pressure Capacity Simple concepts of convoluted shapes K.I.S.S. – Keep It Simple Moron Ever read a copy of Scientific American? I pretended to once. Too many words, not enough pictures. I can tell you from personal experience that it does not impress girls when you are holding a publication upside down. Give me

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Bellows Cyclelife EJMA vs ASME

Metal Bellows Cycle Life – EJMA vs ASME

July 12, 2014

Will the real cycle life please stand up How can three well-respected codes, or design guides, not even be in the same ballpark when it comes to predicting bellows cycle life? On a recent bellows design the EJMA (Expansion Joint Manufacturers Association) curve gave a 7000 cycle rating; B31.3 gave 1150 cycles; and Section VIII/Appendix

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Understanding Pressure Balanced Expansion Joints

July 11, 2014
Click to View Article A formula free explanation To explain a pressure balanced expansion joint, many an engineer will eagerly pencil out off-setting load vectors – also called the beloved free-body diagram. We engineers live and die by free-body diagrams. All the most important questions in life can be explained by free-body diagrams. As much Read More