PTS Flowbench Forum

65mustang393 wrote:

Chad Speier wrote:Bruce, my disk is gold..

A 2.044 plate would be set to flow 293.7 cfm on my bench. (13.29 x DIA²) x SQROUTE of test pressure.

It's the 300 cfm PAP I bought as a set from Bruce.

That doesn't mean anything. You have to measure it, and find out what it should flow. Again, it's math. This is why most of his plates have a diameter on them.

Rick, the above chart should answer your question.

1960FL wrote:

Rick

It flowed 334.2 cfm @ 25" w/FP
It flowed 73.4% manometer @ 422.2 = 309.9 cfm

Chad did you mean to use 442.2 your range calibration

73.4% * 442.2 = 324.6.

Please help me here but in this quote,

The values for all ranges are shown on the Calibration Data Card mounted on your SF-300/600
flowbench for 25” (60cm) of test pressure.

Important Note: The SF-300/600 flow ranges are based on a test pressure of 25”(63.5cm) of
water. If other test pressures are used, the flow scale calibration ranges should be corrected by
the following amounts.

I read this as they say there calibration number in your case #5 442.2 is derived at 25" test pressure.

What does it say next "Following amounts"

Rick

Yes I typed the wrong amount, I since have corrected it.

The following amounts are what Gerald posted as well.

From day one I have found what the hole should flow regardless of it was or wasn't marked.

Not just PTS, but my FP plates, my Audie plates and any plate I own.

No diameters marked on any of the plates, maybe it's on the newer ones. I did buy the PAP set a long time ago though, want to say in 2004 right after I got my SF300. The 400 cfm plate came later, 2006-2008. Had a sticker on it, but no diameter etched/marked on it.

Well if they were made identical to the original set, then you need to look at the reference number.

If your going to use them as a calibration reference, you need to know what they actually should flow, IMO.

100 plate = 98.13
200 plate = 194.88
300 plate = 296.95

The following amounts are what Gerald posted as well.

So my math assumptions were wrong and this make the calibration even worse!

If your going to use them as a calibration reference, you need to know what they actually should flow, IMO.

100 plate = 98.13
200 plate = 194.88
300 plate = 296.95

Chad what CD are you using in your calcs on Bruce's plates?

PAP plates do not have diameters marked on them, this is to ease confusion for those using those plates.

They are compared on my flowbench to the actual PAP that were sent around.

1960FL wrote:

The following amounts are what Gerald posted as well.

So my math assumptions were wrong and this make the calibration even worse!

If your going to use them as a calibration reference, you need to know what they actually should flow, IMO.

100 plate = 98.13
200 plate = 194.88
300 plate = 296.95

Chad what CD are you using in your calcs on Bruce's plates?

The numbers I quoted here were from the original spreadsheet from the Ford bench. The formula I use is based off a .620 sharp edge plate, however the other inputs are different. This is a formula that was given to me 20 years ago and I have just always used it. I will need to dig to find what the differences are in the formula.

Yes, the manometers and calibration of the SF is in the weeds. I said it, again!

Any word from Harold on SF calibration procedures? Did SAENZ just copy this procedure?

Other than price, are there any negatives to renting the box of SF cal plates and calculating what they should flow?