Good morning guys, welcome. Today I'm going to be going over
section A in our catalog. That includes back pressure valves, PR valves, and we'll
also cover the ounces valves. If you guys have any questions don't hesitate to ask.
So we're going to go ahead and dive right into this presentation. All of our
section A regulators are integrated valves and what that means is that the
pilot and the valve body are one piece. As you can see from this picture here
the spring and that upper portion of the valve is connected to the body which is
different from some of our control valves; which the control valves is
standalone from the pilot or whatever is controlling it. A control valve by itself
won't do anything until it's told what to do by a pilot. You don't have to add
pieces on to the valve to get it to work. So back pressure valves are used to hold
back pressure on vessels and equipment and that just helps in the movement of
the liquid. If you think about a separator like this if it didn't have
any pressure being held on it when that dump valve opened up that fluid would
not be forced out of that piece of equipment and sometimes there's several
pieces of equipment that liquid has to move through and if you don't have that
back pressure, it's not going to force that liquid out and cross maybe
50-60 feet of pipe and then up into another vessel. So, holding back pressure
is very critical for the flow of liquid through production equipment. Think of it
like a water gun. If you put water in a water gun and pull the trigger, nothing's
gonna come out of the water gun. It has to be pressurized – you have to pump air
into it, that way when you squeeze the trigger, that liquid is forced out;
that just aids in the separation process. To go over the function of this valve
we'll watch a quick video that'll explain how it's working.
This valve monitors upstream pressure. To adjust the setpoint turn the bolt on
top. The spring pushes down on the diaphragm assembly which positions the
pilot plug. The pilot plug then allows gas from the upstream to push down on
the diaphragm. The flow through this valve is from underneath the plunger. The
flow pushes up on the plunger as the gas is pushing down on the diaphragm. Because
the diaphragm has a larger surface area than the plunger, the same pressure can
hold the valve in a closed position. You have now reached your back pressure set
point and the valve will begin regulating the pressure. If the setpoint
is exceeded, the upstream pressure pushes up on the diaphragm assembly closing off
the pilot plug. This allows gas to be vented from the top of the diaphragm and
the upstream pressure to be regulated.
So now we can go over the function of the
valve and how it operates. The red pressure is upstream pressure and that
is communicated through the tubing to underneath the spring. So you can see the
red pressure is up underneath that diaphragm and the spring is your
adjustment point so the more tension you put on that spring the further down you
adjust the screw the more back pressure that's going to hold. Whenever that
upstream pressure is able to overcome the tension of the spring, so you're
above your setpoint, it's going to lift that diaphragm assembly which lifts
the pilot plug and the pilot plug seats. So the larger ball is going to seat and
the smaller ball is going to eventually raise up off of its seat which is going
to vent the yellow pressure and that yellow pressure is keeping that valve
closed. So as soon as it vents that pressure off, the upstream pressure the
red pressure that's pushing up on that seat is able to push open the valve and
it'll start relieving that pressure. Now once that pressure comes back down below
your set point or that spring is able to overcome and push against the upstream
pressure it's going to seat the small ball.
It's going to keep pushing down and eventually unseat the larger ball which
is going to allow upstream pressure to fill that cavity where the yellow
pressure is and that's going to close the valve. So you have the the upstream
pressure pushing up on the seat but then you also have the same upstream pressure
that fills that cavity, but because that cavity is a larger surface area, it's
able to hold that valve closed even with that pressure pushing up on the
seat. Just because it's a larger area that creates more force to hold the
valve closed eventually this valve will get to the point where it's making very
fine adjustments - the pilot plug does not have to move very far to vent that
pressure to open the valve but it will get to that point where it's just it's
hanging out it's throttling right at your set point it doesn't make large
swings and pressure.
Right there is, there's an o-ring it's kind of hard to
see but there's a communication hole that's drilled right where that stem
goes through and it basically allows that oil just to sit on that stem to
keep it lubricated but that oring in there it has an o-ring and two teflon
backups that keeps that oil from getting into the gas stream. Now that you guys
have a basic understanding on the function of this valve we'll go over some
troubleshooting and common problems that we see with this valve in the field. The
most common issues that we see with this valve is wet gas or trash getting into
the pilot plug area of the valve. They're very small seating surfaces and it
doesn't take a lot to keep those from seating and sealing off the seating
surface. Especially on the smaller ball - it's so small any liquid or trash that
gets on that it's going to keep it from seating off.
And so that's that's the biggest issue that we fight with these valves.
Absolutely, so if there's moisture getting in the pilot plug it's not going
to be able to seat so it's going to be continuously venting. It's not going to
control your setpoint like you want it to. Something you can do without taking
the valve apart – I just run the adjustment screw down quickly and then
back out quickly. Basically what that does is it forces the valve to change
position because it's trying to control a different set point and sometimes you
can get that will cause the the valve to exhaust gas quickly enough to to blow
out that liquid to clear any trash or liquid that's sitting on the pilot plug.
If there's quite a bit of liquid or a big piece of trash sometimes you can't
get that to clear and then you have to open up the valve and and do maintenance
on the valve that way. Another common issue is not removing the plug out of
the oil bowl. When the valve is first installed all of our valves have an oil
bowl and that's just to keep the stem lubricated. When we ship these things
it'll have a plug in it like this one does and that's just to keep – you know
when they're in the box they're on their side – that's just to keep the oil from
spilling out and so when you take this out of the box and install it you've got
to make sure to take out that plastic plug because if you don't this valve
won't be able to exhaust that gas and it won't be able to open up so it's just
gonna stay shut; it's not going to move. It may move once but it's it's not going to
move again. Next we're going to talk about the pressure reducing valve or PR
valve. It functions a lot like the back pressure valve
but it's controlling downstream pressure the most common applications for this
valve would be a section controller on a compressor so you're taking
a higher upstream pressure and reducing it down to the suction setpoint of that
compressor so a PR Valve would be used in any application where you want to reduce
pressure. So not only a suction control valve but if you were going from 250 psi
and you're going down to poly pipe and you needed it to be below 80 psi this
would reduce that pressure down so that way you don't over pressure the poly
pipe. Just anytime you need to reduce pressure and regulate downstream is when
you would use a PR valve. You can see on this picture here, red is still upstream
the blue is downstream pressure and so you have a piece of tubing that
communicates the downstream pressure to underneath the spring so the spring is
still the adjustment point. If downstream pressure is overcome by that spring – so
that means you're below setpoint – then the the pilot plug is going to seat the
small ball and unseat the large ball; which puts the red pressure (upstream
pressure) underneath that diaphragm and that's going to allow that valve to open.
As your downstream pressure then begins to rise back up to setpoint, now once you
get to setpoint the blue pressure or downstream pressure will overcome that
spring the large ball will be seated and the smaller ball will be unseated
allowing the yellow pressure to vent that atmosphere which will then close
that valve. So once you get up to setpoint the valve is going to close and then
once you get below setpoint the valve's going to open. This one's got a little
bit more tubing on it - looks a little bit more complicated - but it functions
basically the same way as the back pressure valve.
This valve controls downstream pressure. To adjust the setpoint,
turn the bolt on top which will compress the spring. The spring pushes down on the
sensing diaphragm assembly which positions the pilot plug. The pilot plug
then allows gas from upstream to flow under the motor valve diaphragm. The
pressure is controlled under this diaphragm to position the plunger to any
changes in flowing conditions. If the setpoint is exceeded the downstream
pressure pushes up on the sensing diaphragm assembly closing off the pilot
plug. This allows gas to be vented from underneath the motor valve diaphragm and
the downstream pressure to be regulated. A constant downstream pressure is then
set. Because the diaphragm has a larger surface area than the plunger, the same
pressure can hold the valve in a closed position when needed. You'll notice that
the pilot plug assembly in this valve is flipped from what it is in the back
pressure valve, and back pressure valve the larger ball is on top and the
smaller ball is underneath. This one is flipped the other way and there's one
more piece of tubing on the pressure reducing valves and the spot where it
vents the the gas either opening or closing the valve is up top so it's in a
different place as well. Next we're going to go over the pressure reducing and
back pressure ounces valves. They operate all in the same way as the regular PR
and BP valves do the biggest differences are the size of the sensing diaphragm
and the size of the adjustment spring. So the adjustment spring is much lighter,
it's smaller and the sensing diaphragm is much larger. You can see this
one here's a pressure reducing ounces valve so the sensing area - that
downstream pressure - is communicated to that diaphragm is very large and that's
just to get it to be able to sense very light pressure – ounces. It's got to
have a large surface area to create enough force to move that spring. The
back pressure will be the same way except we'd be pulling upstream pressure
to that diaphragm to send upstream pressure. The troubleshooting for these
are all the same as the other valves: wet gas is the biggest problem.
For the ounces PR Valve or the OPR. You would be using this for a suction control on a
low suction compressor or anytime you want to reduce down to ounces or just a
few pounds. For the back pressure valve ounces or the OBP you would use that to
hold back pressure on tanks or you could use it to hold back
pressure on very low pressure equipment. There's three spring options available
for this valve there's a two and a half pound a five pound and a 20 lbs. spring.
The 20 lb. spring goes from one pound to 20 lbs.; the 5 lbs. spring goes
from one ounce to 5 lbs.; and the 2.5 lb. spring goes from a
half an ounce to 2.5 lbs. So depending on your control pressure
that will determine what spring that you put in this valve. So you can have, for
the PR valve if for example, you can still have up to 300 pounds on the
upstream side of the valve body and still reduced down to ounces. It's not
going to control very well with that high of a pressure drop but the valve
body is the same as all the other regulators it's just the pilot portion
that's different. Next we're going to go over liquid back
pressure valves. This can be used in applications where you have extremely
wet gas in the valve body and you need to bring in an outside supply of dry air
gas to operate the valve or anytime you're holding liquid back pressure on a
vessel or a pump. What's good about this valve being used in liquid applications
is it has an outside source of gas. So where you see the purple gas coming in
you would bring that in from an air compressor or a higher drier spot where
you can get good dry gas from or air. It's the back pressure valve with an
outside source of instrument air. Converting a regular back pressure valve
to one with outside supply like this one is fairly simple there's just a couple
of pieces you need – so you can go from an AAR which is a back pressure valve to
the AEM which is the liquid back pressure valve fairly easy. So if you're
fighting wet gas and having issues because of that you
can convert to a liquid back pressure valve and solve a lot of those problems.
You should make sure that the elastomers you have in your valve are
compatible with whatever's in your fluid we offer a lot of different elastomers.
If you already have an existing valve that's having issues with failed
diaphragms or our rings you can just buy the repair kit with the appropriate
elastomer type in it and kit the valve and solve those issues. These regulators
are available one inch through six inch and the pressure rating is 300 pounds
for threaded connection or 250 for flange connection.
Thank you guys for
coming out for this training if you guys think of questions later on you can
email us or you can give us a call at our store number and we can answer those
questions our setup more training for you guys.
Thanks for watching this training.
If you found this information helpful and you'd like this training in
person for you or your team, contact your local Kimray store.