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Tycho
09-01-2015, 05:27 PM
I'm looking for the amount of oil (liter/min) that should be injected into the oil injection port on the Howden compressors (the port that goes into the rotors)

There is a reg valve on the oil manifold where you can regulate the amount, and a few years back I got the amount for an XRV204, but I don't remember from who :) but it was a specific amount.

The last answer I got from our compressor package manufacturer was "open the valve 1-2 turns, and if the discharge temp starts rising just "play" with the valve until you get a stable discharge temp"

RANGER1
09-01-2015, 10:19 PM
Tyco,
If you can give model of compressor, conditions that machine runs, suction & discharge pressure, RPM & refrigerant.

Oil pressure has to be set to recommended by Howden as well.

But agree with package manufacturer on set up.

RANGER1
11-01-2015, 01:04 AM
Tyco, WRVI has orifice plugs in both oil injection ports so is sort of preset.
We still instal reg valve in case we want to adjust.
They only give total oil flow on WRVI that I can see
Only XRV give oil Injection amount, which is a little different for different conditions.

Tycho
15-01-2015, 09:27 PM
Tyco,
If you can give model of compressor, conditions that machine runs, suction & discharge pressure, RPM & refrigerant.

Oil pressure has to be set to recommended by Howden as well.

But agree with package manufacturer on set up.

Howden WRV 163, length of the rotor I am not sure of but think it was 193 or thereabouts.

Machine runs on R-507, discharge 10 bar/19.5C, suction is 0.4 bar/-40C

Start up Rpm is 1800 rpm, max is 3600 rpm.


It's not that I don't agree with the manufacturer on the setup of the oil injection to "play around" with it, but I spoke to one guy from there once, and he gave me an exact amount in L/min, and, It's just that for our less experienced technicians they open it too much and we end up with a foam party in the oil separator, and cause too much oil to be thrown out into the system, that's why I ask if anyone have the numbers :)

RANGER1
16-01-2015, 06:27 AM
Howden WRV 163, length of the rotor I am not sure of but think it was 193 or thereabouts.

Machine runs on R-507, discharge 10 bar/19.5C, suction is 0.4 bar/-40C

Start up Rpm is 1800 rpm, max is 3600 rpm.


It's not that I don't agree with the manufacturer on the setup of the oil injection to "play around" with it, but I spoke to one guy from there once, and he gave me an exact amount in L/min, and, It's just that for our less experienced technicians they open it too much and we end up with a foam party in the oil separator, and cause too much oil to be thrown out into the system, that's why I ask if anyone have the numbers :)

Tyco,
I will check out on info I have.
I know Programm says exact amount for XRV, as its a bit different with roller bearings.
It still has to be understood that different conditions like differential pressure across compressor affects amount of oil required, mainly suction end white metal bearings as well as return oil from other bearings into rotors.
On low speed 1800 rpm maybe to much oil injection causing compressor to be noisy (oil compression).
Programm will also give theoretical discharge temperature which can give you something to aim for with injection valve setting at full speed & maximum load conditions.
In your case condensing pressure maybe constant if on ship with sea water which is more stable (correct me if I'm wrong).


Interestingly Mycom programme for R507A under your conditions say's no oil injection required at all & theoretical discharge temperature 55 deg C with 50 deg C oil temperature.
(Is R507A same stuff as R507 say's same in saturated pressure?temperature you refer too)?

Can you advise on oil temperature & what current discharge temperature is on this machine?
Does it have economizer?

Tycho
16-01-2015, 07:41 PM
there is a PM valve on the compressor so it's running with a discharge pressure of 10 bar.

I've been looking for the oil injection amount in our old Kvaerner books, but it only says that there should be a 5mm nozzle in the oil onjection port (before the reg valve was introduced).

RANGER1
17-01-2015, 10:59 AM
Tyco,
Please check your email as have sent some information.
It seems to me no oil injection required on this duty.
See comment adjust regulating valve to achieve required discharge temperature, which in your case
would be 56 degC with 50 degC oil temp.
They only give oil injection oil flow on XRV not WRV etc..
Hope it helps

Tycho
23-01-2015, 09:11 PM
Thanks ranger :)