Scratch and dent scroll compressor

[alwaysFlOoReD]

I was at a physio appointment in town Saturday. Around the corner is a Princess Auto...
They were having a scratch and dent sale...
C$600.00 for everything...
I ended up buying 3 compressors of varying sizes, a 420cc gas engine, and a parts washer tank.
The smallest compressor I was able to fix by replacing the 2 female quick release couplers. The wheelbarrow compressor I'll look at today. The scroll compressor has a 10hp motor and I don't have the amps to use that. So I want to swap the gas engine onto it. Feasible?

 

[cvairwerks]

Can be done, but I think you are going to spend way more time trying to kludge it together than it's worth timewise. You'll have to invent some type of governor system, as I believe that most scroll units want steady rpms.

 

[alwaysFlOoReD]

Looked at the gas wheelbarrow compressor. It won't get past 65psi. One side I can feel suction, the other not much. I have another old compressor head so may change it out, or use the parts to put the 420cc gas engine on the scroll compressor.

 

[Shoreline_]

The blue Hyundai one looks like a screw compressor.

Be aware the rpms have to match to convert the electric screw to a gasoline. You do know you still need electricity for the controls to work on the screw compressor right?

 

[alwaysFlOoReD]

The blue Hyundai one looks like a screw compressor.

Be aware the rpms have to match to convert the electric screw to a gasoline. You do know you still need electricity for the controls to work on the screw compressor right?

Found that out when I took a closer look at it this morning. Also needs power to the rad fan. I'm still researching what needs doing. The gas engine should be enough for 60-70% run time. Use a clutch or unloader. Use pulleys to match engine rpm to compressor rpm. It may end up being better to resell...

 

[RTM]

Be aware the rpms have to match to convert the electric screw to a gasoline

Aren’t some screws designed to run at variable speed, within a range? Back in the day we had two monsters that ran 100% on/off, but I though some of the smaller one could run off a VFD to ramp speed to needed pressure.

 

[Shoreline_]

Aren’t some screws designed to run at variable speed, within a range? Back in the day we had two monsters that ran 100% on/off, but I though some of the smaller one could run off a VFD to ramp speed to needed pressure.

VFD compressors generally dont run 200%. Usually max is 140%. So if you have a 1800 motor and run a 3600 rpm engine on it without changing the pulley size, well... Good luck. Thats double the speed or in VFD world 120hz. Most major compressors run 85hz upper range.

 

[RTM]

VFD compressors generally dont run 200%. Usually max is 140%. So if you have a 1800 motor and run a 3600 rpm engine on it without changing the pulley size, well... Good luck. Thats double the speed or in VFD world 120hz. Most major compressors run 85hz upper range.

Yeah, I was thinking like 80-120% was the range I had seen in the past. 85Hz is a bit above that, so sounds feasible

 

[alwaysFlOoReD]

Well, I finally got around to hooking up power. It runs!
For about 10-15 seconds, then shuts off. I'm thinking some sensor is shutting it down. According to the touchscreen it starts at about 9 amps, and once the scroll starts it goes up to 22 amps and stays. I'll look closer over the weekend.
The tank is missing a valve for the outlet, so it wont build pressure right now.
Unless someone has a suggestion...

 

[MacMcMacmac]

It might run pretty well until something breaks and the factory won't return your calls.

 

[alwaysFlOoReD]

Why would I phone the factory? I like learning...

 

[MacMcMacmac]

OK, that was a bit snarky, sorry about that. I've just seen PA sell screws before then they magically disappeared after a few weeks. For the price it's hard to argue against if it's not doing something critical. The main thing will be consumables. If you have a source for filters and separators it should be OK, but again, I don't know if PA will support you, and I don't recall Hyundai as a compressor manufacturer.

 

[alwaysFlOoReD]

I broke down and called this morning. A real person answered within 30 seconds... (I'm shocked).
The answer they gave didn't work and I have an email sent. I suspect a bad sensor. I'll see how they are for parts when they answer. Its the weekend so I don't expect an answer until monday.

 

[MacMcMacmac]

---

If the grey valve on the discharge line on top of the tank is working properly (minimum pressure valve), the compressor should build enough pressure in the system to ensure oil flow to the screw. It's a good idea to pour oil down the inlet of any screw compressor that you don't know the history of since the air end might actually be dry and not produce any air or oil pressure. Direction of rotation is also critical, although with a single phase motor it is probably not an issue.

Honestly, the more I look at this machine, the more faith i'd put in it than that Eastwood compressor.

22A is half what it's rated for, so it seems like there isn't much compressing going on. Is the inlet valve open? Maybe it loads up to full amps and drops out before the screen registers it?


You will need a 20hp gas engine minimum to drive that screw.

Sounds like the wheelbarrow compressor has a broken valve reed or reeds on the non-pumping cylinder. It should be a trivial fix. The discharge reed may be leaking pressurized air back into the weak cylinder after it hits 65psi, so it's probably a partial fail, or maybe a gasket that separates the intake and discharge sides of that cylinder is leaking

I am surprised you did not yet receive the honourary GJ YOU **** award, so I shall bestow it on you.

 

[alwaysFlOoReD]

I'll pick up some oil and put some down the inlet. Thanks for the heads up.
And thanks for the suckage.

 

[alwaysFlOoReD]

@MacMcMacmac
Thanks for the advice about putting in more oil. That seems to have fixed it. After spending most of the morning rooting around in my piles of "stuff", I broke down and bought some pipe and fittings so I could replace the missing drain valve. Also put in a valve for the outlet. Fired it up and it pumps up to 175psi. Amps built up to a high of 31. Then it goes into an idle mode of 9 amps. Let off some air and it repeated the cycle. I'm stoked! Now to let out all the air and time it to full.

 

[MacMcMacmac]

Cool! Gotta love the easy fixes.