ball valve 6"x4" OR 6" 1

[godel123]

hi
what is the difference in use between these two ball valves :
1- 6"x4" ANSI 600
2-6" ANSI 600


whene using one and not the other.?

many thaks

 

[valvit]

A 6"x4" Class 600 is a 4" bore (ball, seats, body) with 6" flanges and a 6" Class 600 Face-to-Face length. Also known as Reduced Bore or RB.

A 6" Class 600 is a 6" bore with 6" flanges and 6" Class 600 Face-to-Face length. Also known as Full Bore or FB.

Many people in industry will call a 6x4 a "standard bore" valve, while a 6x6 is called a full bore. This is common in downstream applications, but upstream, and in pipelines, calling something "standard" often implies full bore, hence some confusion.

This call-out method, in my opinion, is the best because you are numericalling calling out exactly what you want, with no room for misunderstanding or ambiguity. Tell me 6x4, leave off any reference to RB, standard bore etc, and I know exactly what you want.

 

[godel123]

thanks
whene using RB instead of FB?

 

[valvit]

One of two scenarios...
1) the pipeline must allow the passing of a pig
2) the flow calculations do not permit the slight restriction (higher Cv) of the reduced bore valve.

 

[vpl]

Valvit -- isn't your response backwards? It seems like you're saying when a full bore should be used.



Patricia Lougheed

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[valvit]

Mea culpa.

Yes, that is excatly backwards.

A Reduced Bore valve is used when you do not have the need to pig the pipeline and the flow conditions allow the reduced flow diameter. The RB valve will be lighter, less expensive, and will have a lower torque compared to a Full Bore valve. The lower torque can result in additional cost savings when provided with an actuator.

 

[Cockroach]

What are the chances that ValvIt is "Valve Italia"?

But yeah, 6X4 is a four inch valve with six inch end closures. A six inch valve is six inches straight through without restriction thru the throat (i.e. Ball or Gate).

And again correct, the reduced bore prevents pigging due to the nature of the restriction. I may have other problems like erosion or noise due to the increase of working fluid velocity through the throat, in a gas, perhaps a standing wave given the pressure and sonic conditions.

Actuator load and cost is an important consideration as noted by ValvIt. Good job.

Regards,
Cockroach