Pressure Relief Valve top release 1

[cdbj1958]

We are looking for a top release pressure relief valve. It has to WITHOUT QUESTION release the pressure from the top. Not out the side and then pipe to the top. We have two square channles, one is 12" tall x 8" wide, the other is 9" tall x 8" wide. Both are sealed plastic units with water flow.Some times we get water hammer from air getting inside at the pump,and we also may at times get extra water pressure. We have to install these valves ontop of each unit at the point of water entry. I was thinking about trying to build a square valve with round male on top and bottom of square box. I was thinking along the lines of a flap, that would lift upward at a set pressure. Does anyone know of any such animal on the market?

 

[unclesyd]

You might give these a try. Look at style CON and BU.
Give these people a call they are nice to work with.

http://www.checkall.com/catalog.htm

 

[JAlton]

Kunkle Figure 6182 is a top outlet design available in 1/2" thru 2" inlet. Also Kunle Fig. 548 and Fig. 30 are small 1/4, 3/8 & 1/2" npt inlet.

Also, Circle Seal and Kingston Make small top outlet designs

J. Alton Cox

http://www.delucatest.com

 

[JAlton]

http://www.tycoflowcontrol-na.com/ld/KUKMC-0394-US.pdf

page 2 shows a cut sheet of the Kunkle 6182 top outlet style.

J. Alton Cox

http://www.delucatest.com

 

[Isla]

Can any one tell the most important aspects for not mounting a safety relief valve horizontally ???

Crosby recommends to install only vertical ( spindle vertical) for proper functioning of the valve.

 

[JimCasey]

Safety relief valve should have the spindle vertical for two reasons:

First, they are set that way and the weight of the spring, spindle, spring buttons, and disc are all part of the set pressure loading. Flop it over on its side and the valve will pop early, particularly if it is set for a low pressure or if it has a small orifice.

Second, The guiding of a safety-relief valve is a little casual compared to, say, a globe control valve. Flop the valve over on its side and the parts will probably not line up properly because of gravitational side-loading. Then it will leak.

 

[JAlton]

Jim Casey is correct about the problems with horizontal mounting. Why would you want a top outlet valve if you want to mount it horizontally? Just curious. There are some in line relief valves made by Mueller, Circle Seal and Swagelok (non-code). You could use one of them and just less the outlet go to atmosphere. Some of these designs can be mounted horizontally because the guiding arrangement is similar to a check valve.

J. Alton Cox

http://www.delucatest.com

 

[JimCasey]

Not previously mentioned: The Crosby JQ. Primrily intended as a Chlorine valve, it is still a code valve for gas service. It has a vertical outlet with a screwed-on cap.

However, re-reading the original post, I don't believe you need a safety-relief valve as much as you need a back-pressure regulator. All the usual suspects make back-pressure regulators: Masoneilan, Fisher, Leslie, Cashco/Kaye & MacDonald.

Safety-relief valves are intended as the last protection between a process upset and a crater where your plant used to be. Back-pressure regulators are for continuous regulation and elimination of pressure spikes. BP regulators are made on globe-valve patterns and thus have in-line inlet and outlet. So vertical flow is not a prob.

 

[xcrosby]

I believe that Section VIII of the ASME Code requires the horizontally mounted pressure relief valves be designed and tested in the horizonal position. I'm not exactly sure of the wording. I am not aware of any ASME Code certified valves that have been certified in the horizontal position. Seat tightness is difficult with metal seated valves. Soft seated valves usually work pretty good in the horizontal position. In my 20 years with Crosby there was only one aplication where horizontally mounted valves were made for a specific applicaton. This was for a nuclear power plant where the system was designed with the valves in the horizontal position and it was too costly to redesign. These were small, high pressure valves where the weight of the parts were insignifiant compared to the spring force. Don't design systems with the pressure relief valve mounted in the horizontal position unless the unless there is a real good reason and you have a valve manufacturer that will insure proper performance in the horizontal position. Many inexperienced system designers get into trouble because they are unaware of these problems.