Force on pipe Elbow

[farhadsh]

Still can’t get good idea on flow force on pipe elbow. Based on formula force of flow on pipe elbow equals internal pressure by pipe area plus or minus flow momentum change. However when looking for force required by support to hold elbow in stationary condition it is said only to consider momentum change and not internal pressure by area. Looking for some clear input by a pipe support engineer
Thanks

 

[LittleInch]

Depends on whether the elbow is considered to be mechanically connected to the pipe (welded or nechanical connection) or not (push fit).

If connected the end cap force becomes an axial force in the pipe, but momentum change is a force on the elbow.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[farhadsh]

How to calculate momentum force on elbow?

 

[DSB123]

If you are a true mechanical engineer you should have covered this whilst doing your Mechanical Engineering Degree!!!

 

[PEDARRIN2]

While this forum is good for getting guidance, try to figure it out before asking what could be basic questions so you do not get the above response.

Use google and see what you can find.

Also, use the search option on the forum to make sure the same question has not been asked.

Attached is one item I found when researching the same thing.

 

[bimr]

As was stated in the other thread, you are using a product that is considered to be a rigid pipe system and doesn't require pipe supports on each elbow:

"These products (Victaulic HP-70ES) can be considered to have system behavior characteristics similar to those of welded or flanged systems, in that all piping remains in strict alignment and is not subject to deflections during operation. For this reason, these products require support techniques similar to those used in traditional flanged or welded systems."

Victaulic HP-70ES

Contact Victaulic for additional details.

 

[farhadsh]

Thanks pedarrin and bmir, With using hp-70es vic coupling do you think pipe support should be installed right at elbow or it is okay to be installed somewhere on pipe upstream and downstream of elbow? 70-es has higher allowable tensional end loads than my piping full thrust loads however it has limited max allowable bending moments. I am curious if pipe support is installed upstram and downstream of elbow then there will be bending moments on coupling beyound allowable but I am not sure if this is true and how to calculate it
Thank you

 

[bimr]

Review the Victaulic design guidance and the example #6.