PDA

View Full Version : weighing scales R-508b







i hate the cold
19-07-2007, 11:17 AM
Hi all fridgemen can anyone help me, i need to find a set of weighing scales that are very accurate and that can hold back the high pressure of R-508b and R-23, because the gas charge has to be within the nearest gram with a minimal charge.
Kindest Regards
Graham.

norseman
19-07-2007, 02:14 PM
Hi all fridgemen can anyone help me, i need to find a set of weighing scales that are very accurate and that can hold back the high pressure of R-508b and R-23, because the gas charge has to be within the nearest gram with a minimal charge.
Kindest Regards
Graham.
Since you are into so small charge it is strange that your systems does not use a static charge. Much easier to handle and pretty exact +- if the all are
inside an ambient of 20c +- a couple of c. I use in a few cases else a fine needle valve on a tube from the bottles so the flow is so small so you can follow the grams slowly passing by and then close. You need those systems pretty dry so a filling weight can give you moisture by trapping under the low transfer temperatures.
Per

pendlesteve
20-07-2007, 12:53 PM
I would suggest you use the scales for the correct charge and your well kept manifold as the shut off valve.
Have you looked at the ITE scale mod' WS-055 which has a resolution of 2 gr & accuracy of 1%.

norseman
20-07-2007, 01:14 PM
I would suggest you use the scales for the correct charge and your well kept manifold as the shut off valve.
Have you looked at the ITE scale mod' WS-055 which has a resolution of 2 gr & accuracy of 1%.

Sure a manifold should be involved, but they are for sure not good as a fine regulator and it is easy to get
50 bar's and up of pressure on the intake on the manifold so with bad luck you either "adjust" the pointers to a "new" range or overfill in a second. By using a fine needle valve or similar as a start point on the bottle side, you avoid a lot of surprises as I can see it. 95% at least of the many hundreds systems I filled over the Years have a static fill information which works well and give a more relaxed time doing it. Strange that this is not common in this case too.

ultralo1
22-07-2007, 04:17 AM
One of the field expiedeint regulators that I use is a lenght of cap tube brazed into a shreader on one end and brazed into a piece of 1/4inch and flared to go onto the tank.