3" Cla-Val Pressure Relief Valve with class 300 flanges, Hard time finding fittings and reducer

[Albertdorian]

Hi everyone, I am working on a small pump station where I'm installing a pressure relieve valve (PRV) to an existing 4 D.I. pipe. However, the Pressure Relief Valve that I ordered is a 3" nominal diameter with class 300 flanges.

My plan is to add 3" to 4" reducers so that i can connect to the existing 4" pipe. The problem im having is that i am having a hard time finding ductile iron or even steel 3" to 4" reducers with class 300 flanges, otherwise i wont be able to connect to the PRV. almost everything out there is made with flanges class 150 which are not compatible with class 300.

Even if there was, then i run into the problem of finding a DI pipe to Flange coupling adapter so that i can connect those fittings the existing DI, because all those adapters that ive seen so far are made for the class 150 flanges.

I will appreciate anyones input that can help me solve this.

I will try to attach a sketch of what im trying to do here.

Thanks everyone

 

[ashtree]

Do they need to be Class 300 for the pressure you are operating at?

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[Albertdorian]

I didnt know how to reply other than posting here, .. back to your question, are you asking if the PRV needs to have class 300 flanges? according to the manufacturer that actually came down to check the site and the pressures we are dealing with, yes. And the thing is that we already order it and received it.

 

[ashtree]

To reply you just post like you have done.

I can't say categorically that there is no such thing as a CLASS 300 reducing taper in existence but they are rare at least off the shelf.
You will probably have to use a long necked 3 inch flange and then obtain a 4 inch by 3 inch weld on tapered reducing flange. The reducing flange basically is a 4 inch flange with the correct bolt pattern and thickness etc but only has a hole the diameter of a 3 inch pipe in the centre. Its a little more complex than that but that is the description in simple terms. You would have to get a suitably certified welder to do the job if it is to be pressure rated.

No doubt the 3" PRV was cheaper than the 4" PRV but sometimes you have to look at the whole job rather than the cost of key components.

Overall i would be surprised if you have saved anything.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[LittleInch]

Have you thought about a flange plate adapator between your 4" #300 valve and your 3" #300 relief valve.

Something like this, but machined to suit. So long as the plate is equivalent to a nut thickness and you tap the holes then it will work, but is a "special" and doesn't fall into any codes or standards. The hole size will need to be the same size as the 3" bore.

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

 

[hydrae]

Albertdorian

Next time you need a one size smaller Cla Valve, order the full size but in the 600 series

In this case you ordered a 50-???? in a 3", to get the reduced port valve order a 650-???? in 4"
you will get a 3 inch valve with 4 inch flanges

As to solve your current issue

USAbluebook custom builds flange adapters

https://www.usabluebook.com/p-282622-flange-spacer-reference-number.aspx

item no 10001 available in carbon steel with fusion nylon coating or stainless

Hydrae

 

[Albertdorian]

Hy guys im back, thans by the way for all your help. I found a this company that makes Ductile Iron Fittings with class 250 flanges, They also have the Concentric reducer from 4" to 3" with class 250 flanges on both sides, just as the one hydrae provided. I keep noticing that some manufacturers interchangeably call out class 250 and 300 where the proper way to call them is 250 (only when dealing with cast-iron) and 300 (for ductile iron and Steel)

Guys let me know what you think. Thank you

 

[Albertdorian]

This is the company im talking baout

http://www.tylerunion.com/upl/downl...al-sheet-c110-flange-joint-250lb-2b07e4e5.pdf