4 replies to this topic

[WilliamN]

Dear peers,

Based on my understanding for API 600 (carbon steel gate valve), and API 603 (stainless steel Gate valve), if a vendor states that their gate valve meets the spec of either API 600 or API 603, the valve is a full port valve.  I am interested to get an second opinion from other professionals if my understanding is correct.

 

Thanks.

William

[Napo]

William,

Normally the gate valves are reduced port, but you need to specifier if you need full-port or full-bore.

The Api 600 gives the range of flow pass, this is between reduced to full port. In your situation if your supplier warrantie that yours gate valves are full port is a good option.

Normally full port valve is more expensive that reduced port. Do you need really a full port valves?

Napo.

[WilliamN]

Napo,

thanks for your reply. API 520 , Part II states that "The flow area in the outlet isolation valve should be equal to greater than the outlet area of PRV".  This governs that the isolation valves on vent line should be full port.

 

API 600 specifies the standard for gate valves. its scope section used the wording " full port opening" among other terms. Some vendors list their valves meet API 600.  I try to get other peers' opinion that Meeting API 600 means a full port valve. For now, I have asked vendor to state their valves meet API 600 and full port. The vendor might think my request is redundant / nuisance.

William.

[ankur2061]

Bill,

 

Full port ball valve minimum bore diameters are provided in Annex A of ASME B 16.34. This is also cross-referenced in the standard "MSS SP-72-2010 - Ball Valves with Flanged or Butt-welding Ends for General Service". The following is mentioned in this standard:

 

 Full_Port_Ball_Valves.png   26.81KB   14 downloads

 

 

Hope this helps.

 

Regards,

Ankur

[Napo]

William,

 

The API 520, Pat II says:

 

"5.2 Minimum Diameter The nominal size of the inlet piping and fittings shall be the same as or larger than the nominal size of the pressure relief valve inlet connection as shown in Figure 2 and Figure 3.

 

For inlet piping to multiple relief valves, the piping that is common to multiple valves shall have a flow area that is at least equal to the combined inlet areas of the multiple PRVs connected to it."

 

Nominal size, this requieriment doesn´t make obligatory the full-port, maybe if you want to put that is your election.

 

Napo.