Pipe Elbow to Flange Connection

[napster385]

Hi Everyone,

Is there a provision in the ASME Piping codes that restricts welding of welding neck flange connection directly to a pipe elbow fittings? If there is none, will this normally affect hydraulics in the pipeline system.

Appreciate your response. Thanks.

 

[europipe]

It is normal and done all the time,
(how long are You a piper ?)

 

[moltenmetal]

Any two fittings with butt welding preparations can be welded directly to one another, assuming the bores match or are bevelled to match. Pup pieces of pipe are not required between them.

Ordinary butt welding fittings, particularly elbows and tees but also some sizes of reducer, should not be inserted into socket weld or slip-on flanges- fit them up dry and you'll quickly see why. When this is to be done, the fitting used should have either a piping pup piece welded to it or it should be a fitting made with a longer than normal straight pipe "land" on the end to be inserted into the flange.

Will this affect "the hydraulics"? The hydraulics are what they are- you estimate the losses based on the actual geometry of the piping.

 

[pennpiper]

napster385,
Please go here and read the article.

http://pipingdesigners.com/contents/blog/146-blog-1p-fitting-to-fitting

Sometimes its possible to do all the right things and still get bad results

 

[LittleInch]

Is there a provision, no.

Is it always a good idea, no. Especially entry to pumps, meters or other equipment, the elbow can induce swirl and create non uniform flow. Normally entry to pumps or vessels should have 5 to 10D straight pipe or a flow conditioner.

Give us the example you're looking at.

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

 

[boxtobox]

It should not be a problem.