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mutley racers

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I have a job where I need to run 30 metres of 28 mm and 10 metres of 22mm copper tube. Now there is no gas hob in the place so I need to light the gas while purging. What right do you guys make up in this scenario. Cheers
 
+1 and what you feeding cant be much after 40m total

and a bunsen burner
 
sorry mutt, but i disagree!! probably wrong though!
whats the meter?
g4 i make it 0.04614m3
 
sorry mutt, but i disagree!! probably wrong though!
whats the meter?
g4 i make it 0.04401m3

So to calculate the installation volume it is G4 metre 0.008 + 30 metres 28 mm 0.0162 + 10 metres 22mm 0.0032 + 10 % for fittings is 0.0301?

Have I made a mistake some where
 
So to calculate the installation volume it is G4 metre 0.008 + 30 metres 28 mm 0.0162 + 10 metres 22mm 0.0032 + 10 % for fittings is 0.0301?

Have I made a mistake some where

must be! 30mx28mm is 0.0387m3 & 10mx22mm is 0.01728m3 !!

according to the rays gas app...
30mx28mm + 10mx22mm not adding any fittings its 0.04401m3 or 0.04614m3 with fittings!!

think youve been hoping to do it in 10mm aint u? lol
 
must be!
according to the rays gas app...
30mx28mm + 10mx22mm not adding any fittings its 0.04401m3 or 0.04614m3 with fittings!!

you got a link to rays app?
 
Just done it manually and I make it 0.03014m3

30 x 0.00054 = 0.0162
10 x 0.00032 = 0.0032
meter = 0.008

total = 0.0274

10% = 0.00274

Total = 0.03014

Don't think I've missed anything?
 
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30 x 0.00053 = 0.0162 + 10 x 0.00032 = 0.0194 (IVp) + 10% (IVf) = 0.02134 + 0.008 (IVm) = 0.02934 x 1.5 = 0.04401

If the pipe is feeding a boiler just turn it on. It will purge itself to a source of ignition.
 
30 x 0.00053 = 0.0162 + 10 x 0.00032 = 0.0194 (IVp) + 10% (IVf) = 0.02134 + 0.008 (IVm) = 0.02934 x 1.5 = 0.04401

If the pipe is feeding a boiler just turn it on. It will purge itself to a source of ignition.
with a wooosh!
 
Every app you use will prob give different answer.
If you want accuracy you need go old school and work out using your fingers and toes with standardised formula.
I got 0.02934 volume for a G4 meter.
 
30 x 0.00053 = 0.0162 + 10 x 0.00032 = 0.0194 (IVp) + 10% (IVf) = 0.02134 + 0.008 (IVm) = 0.02934 x 1.5 = 0.04401

Tamz, I was taught you only multiply x 1.5 of pipework is 35mm or over, or you have a U16 or bigger meter...
 
Just done it manually and I make it 0.03014m3

30 x 0.00054 = 0.0162
10 x 0.00032 = 0.0032
meter = 0.008

total = 0.0274

10% = 0.00274

Total = 0.03014

Don't think I've missed anything?

Almost right. :yes:
Went wrong by adding the meter before adding your 10%.
 
Technically if its a g4/U6 and pipework 28mm or under you don't need to bother working out the IV. The PV is 5 x cyclic volume (0.002) = 0.01
 
Every app you use will prob give different answer.
If you want accuracy you need go old school and work out using your fingers and toes with standardised formula.
I got 0.02934 volume for a G4 meter.

You've added 10% to the pipework before adding meter volume, right?
 
Technically if its a g4/U6 and pipework 28mm or under you don't need to bother working out the IV. The PV is 5 x cyclic volume (0.002) = 0.01

True, as that is minimum purge vol but I want to check whether I was taught wrong about the multiplying by 1.5?
 
Almost right. :yes:
Went wrong by adding the meter before adding your 10%.

Now that's a funny thing. When I first did ACS, I was taught to do your method. Subsequently I was taught to add meter volume first and then add 10%.
 
True, as that is minimum purge vol but I want to check whether I was taught wrong about the multiplying by 1.5?

No its right enough.
You would only bother working out the IV for a purge if there was > 28mm or a G10/U16 on it so it is irrelevant in this case anyway.
 
Now that's a funny thing. When I first did ACS, I was taught to do your method. Subsequently I was taught to add meter volume first and then add 10%.

Some acs centres have their heads up their rses.
Gimme a minute and i'll post a pic from UP1B.
 
Some acs centres have their heads up their rses.
Gimme a minute and i'll post a pic from UP1B.

Just checked the Construction Skills textbook. 10% added to pipework and then meter volume added. So yeah, the worksheet the assessment centre gave us was wrong!

Although, I noticed something else in the book - we've all been adding 0.008m3 as meter volume, but that is meter internal volume. Meter purge volume is given as 0.01m3 for U6/G4.

God, I'm sad...
 
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