Linking 2 compressors

[AVI_8]

So these (2) machines you post are not the same. Only the tiny electric one overheats.

I have 6 compressors up to 200 cfm, and none, even the cheapest Harbor freight electric (3 hp)
have to stop for cooling. Routinely blast using one of my 2 DIY cabinets for hours at a time, 3 pots
for outside usage.
Mostly outside these days using a 1/8" nozzle on my 10 hp Quincy electric. 300-600 lbs of sand is a routine job.

The 200 CFM is driven by my tractor PTO and I've run a 3/8" nozzle on the large pot (300 lb Clemco
pot with remotes) I did 12k lbs of coal ash one year with that set-up.

That’s all very impressive and typically yanky where everything has to be bigger, but in this little damp island most of us have single phase 230 volts and there’s no way in hell you’ll run a 10 hp from that

 

[Farside]

So these (2) machines you post are not the same. Only the tiny electric one overheats.

I have 6 compressors up to 200 cfm, and none, even the cheapest Harbor freight electric (3 hp)
have to stop for cooling. Routinely blast using one of my 2 DIY cabinets for hours at a time, 3 pots
for outside usage.
Mostly outside these days using a 1/8" nozzle on my 10 hp Quincy electric. 300-600 lbs of sand is a routine job.

The 200 CFM is driven by my tractor PTO and I've run a 3/8" nozzle on the large pot (300 lb Clemco
pot with remotes) I did 12k lbs of coal ash one year with that set-up.

Fred wins the Willy-Waving Compressor Contest this week.

 

[Morrisman]

Fred wins the Willy-Waving Compressor Contest this week.

Pah. I spent 23 years working offshore, specialising in high pressure compressors: 2000psi, 1800 cfm, running constantly for 7 days at a time. First stage piston was 24" diameter, at 2 bar, 5th stage was 3", at 140 bar.

I can probably dig out some pics, but we had 3 Sulzer Burkhardts running in the same engine room sometimes, on certain jobs.

Duty cycle on a compressor must mean they don't have proper cooling, as they trip off on overheat. I added electric fans to both my small home air compressor and my arc welder, and never had problems with the 'duty cycle' after that, and that was in 35c ambient temps.

'Duty cycle' equals 'insufficient cooling' in my book.

 

[mtt.tr]

Fred wins the Willy-Waving Compressor Contest this week.

Don't mind him, he just forgets America isnt the entire world.

 

[Burdekin]

Ive got 2 of exactly the same compressors and have linked them together but they are not sharing the work, one is particularly lazy with the other doing most of the work.
I have pipework coming out of each with a non-return valve in each pipe, before they tee together.
What have I done wrong?

Thanks.

What's you're electrics setup for the compressors? That is the main consideration regarding how you switch them, together, separately and what pressures. To reduce starting loads I have them switched at slightly different pressures reducing starting loads at the same time but also have them on different ring mains, it just depends on how much air is required whether both are needed to run. My compressors are also rated at 10bar but I have lowered them to 8bar, that also helps with starting loads when working.

I'd also get rid of the non-return valves, not needed and just an obstruction in the line.

 

[addjunkie]

Pah. I spent 23 years working offshore, specialising in high pressure compressors: 2000psi, 1800 cfm, running constantly for 7 days at a time. First stage piston was 24" diameter, at 2 bar, 5th stage was 3", at 140 bar.

I can probably dig out some pics, but we had 3 Sulzer Burkhardts running in the same engine room sometimes, on certain jobs.

Duty cycle on a compressor must mean they don't have proper cooling, as they trip off on overheat. I added electric fans to both my small home air compressor and my arc welder, and never had problems with the 'duty cycle' after that, and that was in 35c ambient temps.

'Duty cycle' equals 'insufficient cooling' in my book.

For two compressors to work well its better if they both feed the same reservoir, and they operate lag and lead based on reservoir pressure.

But if were willy waving about compressors try taking gas upto 350bar at a rate of 400MMscf/d, non stop till the wheels fall off!

 

[knighty]

Remove the one way valves between them

You don't need them

Without them the pressure in both tanks will equalise and they'll run more happily together