PPC | Standard Process Gauges

Winters PTR Tamper Resistant Process Gauges are used in Process industry where tamper-resistant gauge/seal is required to protect against maintenance errors in the field.

PPC Spec Sheet

SS304 - A common standard for stainless steel due to its malleability, high corrosive resistance weld-ability  

SS316 - A molybdenum stainless steel that provides excellent tensile, creep and stress-rupture strengths at elevated temperatures

Now we’re going to talk about the Winters PPC gauge, which is a process gauge. The typical process gauge in the industry today is 4 ½ inch dial size and it comes with what’s called a phenolic turret safety case. The reason it’s called a turret case because, if you were to lay it on its back and take a look at it, it is sloped and then the socket coming out the bottom kind of makes it looks like the turret on the top of a tank so that’s how I got its name.

 

The reason it’s called a safety case or a full pattern safety case is behind the dial is a solid wall with only holes going through it to allow for fill fluid and to allow for the pointer shaft to come through. The way it works is that, if you’ll notice on the back of the gauge or the case, there’s a plate that has a bladder on it. You’ll notice there’s some little aluminum tabs. At 8 psi, this back will blow out. The reason it’s called a safety case is if the operator was standing in front of the gauge and the board on tube was to have catastrophic failure, the pressure would be relieved out the back and not come out the front towards the operator.

Some of the features of the Winters PPC or process gauge is the Winters gauge is dry on the shelf but is field liquid fillable just by removing the plug at the top, glycerin or whatever fill fluid you want to use, can be poured in to the appropriate level then the plug put back in and it’s good to go. Many of our competitors in the past, you had to buy special kits or order the gauges ahead of time so that they would be liquid filled. Winters, on the other hand, has always provided liquid fillable gauges off the shelf.

The PPC gauge comes with brass or stainless steel internals. More common in the industrial setting would be be 316 stainless steel wedded parts, which means your socket and your tube are 316 stainless steel. It also has a full pattern 304 stainless steel movement in it.

The accuracy of the Winters process gauge is half percent full-scale. The process gauge is the most accurate gauge you can use in an industrial setting. Any more accuracy than that, going to quarter percent, those gauges are made for laboratory testing situations. But for the rigors of industrial process, the process gauge is the most accurate gauges you can use.

Again, as we said, they come with a micrometer pointer, which means you can take the front bezel off, which is generally Plexiglas but it can also be laminated safety glass if desired, fine adjustments for calibration can be made using the micrometer pointer and these gauges are fully repairable. The accuracy, as we said, is half percent and they come in pressure ranges from full vacuum compound up to 20,000 psi off-the-shelf.

Connection sizes are standard half inch MPT bottom or quarter inch or they can be back connect. On the Winters version, for a back connected gauge, it cannot be liquid filled; we have to go to a dampened movement, which we’ll discuss in a moment.

The Winters process gauge also comes with over and under load stops. What that means is they are physical metal stops that will stop the movement from coming off of the gears so if you had slight overpressure or slight under pressure, the gauge won't lose its calibration. Over and under load stops won't stop any gauge from getting damaged if you exceed the overpressure by more than 25% or if you go down into full vacuum.

Because the process gauge, and even the PFP gauge that we spoke of before, is used in an industrial marketplace, anything that 316 stainless steel will handle that doesn’t have solids in it, the gauge can handle on its own. However, if you start getting into corrosive fluids or fluids that have large particles in it that could clog the gauge, then you may need to go to what people call a chemical or diaphragm seal. This gauge mounts easily to the top of one, the whole assembly is evacuated and filled with an incompressible fluid, thus allowing this gauge to be used in very corrosive or hazardous environments.

The process gauge only comes in the four and a half. If it’s psi, with all Winters gauges, if it has an R1 at the end of the part number, it will be psi only. If the part number has no R1 or no R designation at the end, then it’s psi/KPA dual scale.

One of the features of this case, in addition to being a safety case, you’ll notice that it has the 3 feet that are actually part of the case. What this allows is this gauge can be mounted to a wall, as you can see the holes, and a screw can be put in so that it can be mounted and screwed right into the wall and thus do your piping from there. You don’t have to add an extra flange and because it is raised, it still allows the back to blow off if there was a failure of the board on tube.

The gauge can come panel mount, we do make some special brackets that will pull it up to the back of a panel that’ll hook in and hold it in place. We also make a hinged front ring case, which is not liquid fillable, but again, will allow it to be put into a panel.

They generally come dry off-the-shelf. If you desire it to be liquid filled, you state it, and that’s designated by a –G at the end of the part number stating that it’s glycerin filled. If silicone is required because of temperature constraints, then there would be a –SF at the end of the part number.

All of the internals on the process gauge on the stainless steel one are stainless. Even if the wedded parts were brass, the movement still would be stainless deal.

Yes, they do come in brass wedded parts and, generally, that would be for wastewater treatment plants and things like that where they’re being put on diaphragm seals anyway so they really don’t worry too much about the stainless.

The PTR, if you look on the website, what you’ll find is the PTR has a diaphragm mounted and welded to the bottom of the gauge. What that does is, if someone is installing it, because it’s welded, you don’t have to worry about them breaking the diaphragm away from the gauge and losing the fill fluid because, once you do that to an assembly, you render it useless; it can no longer stand the pressure.