Gas regulator

Submitted: Wednesday, Dec 30, 2015 at 11:32
ThreadID: 131237 Views:1988 Replies:5 FollowUps:7
This Thread has been Archived
Have just adjusted my gas regulator from 8 inches to 11 inches pressure. The adjusting screw had come loose and took about 6 turns to adjust up. ( made a manometer to read the pressure ) For about the first 4 turns there was no resistance on the screw.
My question is does the regulator only adjust pressure or pressure and flow proportionately.

Back Expand Un-Read 0 Moderator

Reply By: The Bantam - Wednesday, Dec 30, 2015 at 12:02

Wednesday, Dec 30, 2015 at 12:02
Just wondering why you would adjust the pressure.?

If you change pressure, flow will also change ....... its basic Ohms law. or whatever they call it in gas.

pressure / resistance = flow

All you gas devices will be designed around a specific pressure wise to stick with the specified pressure.

cheers
AnswerID: 594298

Follow Up By: Greenant - Wednesday, Dec 30, 2015 at 13:58

Wednesday, Dec 30, 2015 at 13:58
The reason I adjusted the reg was because Fridge in van not getting below 10 degrees on gas good on 240 and had been getting worse over a period of time. Therefore problem with gas supply
checked at regulator only getting 7.75 inches . found adjuster loose in the reg and it had wound out hence the 7.75 reading. Maker of fridge recommends 11.5 inches adjusted the reg back up to 11.5 inches Bingo fridge working as it should.

I was wondering if gas flow is proportional to pressure

ie higher pressure more gas flow bigger flame more cooling
0
FollowupID: 862678

Follow Up By: Allan B (Member, SunCoast) - Wednesday, Dec 30, 2015 at 14:09

Wednesday, Dec 30, 2015 at 14:09
.
"Pohms" actually Bantam. (Pneumatic Ohms)

I 'coined' it years ago for calculations related to pneumatic process control instrumentation.
Does not apply quite as accurately as electrical Ohms due to compressibility and other factors peculiar to the fluid, but did have its uses. (We did use more elaborate formulae for serious fluid flow calculations).

Then there are "PneuMhos" which is the pneumatic form of conductivity.
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

1
FollowupID: 862680

Follow Up By: Malcom M - Thursday, Dec 31, 2015 at 08:16

Thursday, Dec 31, 2015 at 08:16
" its basic Ohms law. or whatever they call it in gas."

As an electronics engineer I love that :)
0
FollowupID: 862725

Reply By: Allan B (Member, SunCoast) - Wednesday, Dec 30, 2015 at 13:50

Wednesday, Dec 30, 2015 at 13:50
.
Just pressure.
Flow is determined by the adjustment of the appliance.

I take it that you made a U-Tube manometer using water and measured the "11 inches" from the interface in one limb to the interface in the other?
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

AnswerID: 594304

Follow Up By: Greenant - Wednesday, Dec 30, 2015 at 14:01

Wednesday, Dec 30, 2015 at 14:01
Yes made a U-Tube
0
FollowupID: 862679

Follow Up By: Allan B (Member, SunCoast) - Wednesday, Dec 30, 2015 at 14:22

Wednesday, Dec 30, 2015 at 14:22
.
Sorry Greenant, my answer may have confused.

The regulator does not "control" the flow, only the pressure, but as Bantam said, if you make a change to the applied pressure the flow of gas through an appliance will change proportionally.

If the supply pressure is held at a constant value then the flow through an appliance can be varied by adjusting the appliance's flow control, e.g. the hand valve on a stove.

Your re-setting the regulator to the specified value is good. Setting it to higher values can produce possibly serious problems with the burner of the appliance.
Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

0
FollowupID: 862681

Reply By: swampy - Thursday, Dec 31, 2015 at 08:39

Thursday, Dec 31, 2015 at 08:39
hi
The regulator will have a flow / pressure performance chart .
To a certain point the reg of a given size will deliver more gas at increasing pressure .

swampy
AnswerID: 594352

Follow Up By: Erad - Thursday, Dec 31, 2015 at 09:50

Thursday, Dec 31, 2015 at 09:50
If you increase the pressure, the flow will not increase linearly as a result. To double the flow, you need to increase the pressure 4 times - it is a squared relationship. This is academic anyway - you will get more gas flowing if you increase the pressure - just not porportionally more.
0
FollowupID: 862731

Follow Up By: swampy - Thursday, Dec 31, 2015 at 10:05

Thursday, Dec 31, 2015 at 10:05
hi
as a tech ,there will be a ..## flow pressure chart available for the reg ## .. I do understand the relationship may not be linear
There will /maybe many physical attributes that restrict the reg from achieving perfect performance .
Basically we are talking about the same thing from different ends .

swampy
0
FollowupID: 862735

Reply By: Racey - Thursday, Dec 31, 2015 at 10:31

Thursday, Dec 31, 2015 at 10:31
All LPG appliance sold in Australia are are rated and approved based on a gas pressure of 2.7 kilo pascals which equals 11 inches of water. That measurement should be at the appliance.
AnswerID: 594357

Reply By: Greenant - Thursday, Dec 31, 2015 at 15:11

Thursday, Dec 31, 2015 at 15:11
Thanks everyone for their input

Just checked fridge temp 38 degrees ambient inside van fridge temp 1.2 degrees with temp control at halfway mark. Its amazing how dramatic a little less gas pressure can change the cooling effect and how easy it was to check the regulator pressure and to adjust.

Once again thanks for your imput.

greenant
AnswerID: 594371

Sponsored Links