Oil coming out of breather 4

[Stanley2113]

I have some Sulzer pumps that have oil coming out of the breathers. The pumps aren't that big, mostly driven by 15-25HP motors at either 1800 or 3600rpm. They all have the Watchdog oiler sight glass combo.
What could be the cause of this?
Could a different breather be utilized that could fix this issue?

https://files.engineering.com/getfi...20fa-4dfc-8311-00182621da23&file=breather.jpg

Thanks for any assistance.

 

[EdStainless]

Is this a new occurrence?
Are you positive that they have the correct amount of the correct oil in them?

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P.E. Metallurgy, Plymouth Tube

 

[Stanley2113]

I don't think it's a new occurrence, but I've only been at this site since Nov 2017. While looking at other pumps nearly every sulzer pump we have with that breather is doing it. It was brought to my attention when one of the pumps was written up for an oil leak.

The sight glasses are showing the proper oil level.

 

[JJPellin]

The Watchdog oiler is internally pressure equalized. With this oiler, there is no reason to have a breather. Remove the breather and plug that connection.

Johnny Pellin

 

[JJPellin]

A Watchdog oiler is not adjustable. It controls the oil level to the center of the piping connection it is connected to. Sulzer housings have ports for this use. But, they also have ports that are positioned for a Trico oiler that controls the level to the top of the pipe. And they have another port that is positioned to have the correct oil level at the bottom of the port. Since the Watchdog oiler is also used as the sight glass, if the oiler was connected to the wrong piping port, it would still appear to have the correct level. Are you sure the oiler is connected to the right port and that the level in the housing is not too high? You should have a drawing like this one that shows which port is which.

Johnny Pellin

 

[JJPellin]

Are you sure that the breather is on the correct port on the top of the housing? If the breather is located directly above a slinger disk, it is more likely to leak, as well.

Johnny Pellin

 

[Aub_Engineer]

Do you have an oil mist connected to the bearing housing? I've seen purge mist attached to bearing housings and the oil would collect near the breathers.

 

[JJPellin]

If you verify that the oiler and the breather are connected to the correct ports, and you insist on using a breather, then you could simply add a length of pipe below the breather to raise it up higher. Even 6 inches of pipe could be enough to let any droplets or mist of oil drop out and run back down into the housing.

Johnny Pellin

 

[Stanley2113]

Just checked everything and the oiler is in the correct spot and the breather was where the drawings said it should be which was the closest to the impeller with the middle port plugged which is over the slinger ring and the third port was over nothing really. The oil was slinging off of the radial bearing right into the breather port. I swapped it with the third port which is open to the bearing housing, but didn't have anything shooting out of it when I pulled it.

https://files.engineering.com/getfi...c-4cad-b79b-1f02554bd44c&file=breather_02.jpg

 

[Strong]

I recall the Trico website showing that oiler location (which side) was based on shaft rotation direction. It doesn't matter on some bearing, but it may be important on your bearing.

Walt

 

[electricpete]

I always read JJPellin's comments with interest because that man knows a lot about pumps!

The Watchdog oiler is internally pressure equalized. With this oiler, there is no reason to have a breather. Remove the breather and plug that connection.

I dont' fully understand the basis for that comment. If somehow a vacuum does develop in the casing (*), it would affect level control on this style oiler imo. The oiler will attempt to maintain level at the top of the slant/cut of that vertical tube. If pressure over the oil in the pump sump is lower than atmospheric pressure over oil in the oiler, then the level in the oiler will be higher (like a manometer). I have seen it happen on a vertical motors without breather, and we used an oiler with an equalizing line connected back to the sealed reservoir to combat it.

* How might internal vacuum develop in reservoir? There is a big difference between pumps and motors. An open construction motor sucks air into the center of top of the rotor in below the upper bearing reservoir and often creates a vacuum in that reservoir via the shaft standpipe (if reservoir is not well vented). A pump doesn't have that problem to contend with. I gather the only thing to cause pressure change in pump reservoir would be thermal changes. I imagine venting through the seals would be enough to equalize pressures during slow thermal contraction and keep the pump housing at atmospheric?

for op

Fwiw, I agree that using a standoff pipe to lift the vent cap higher might work. We have also used successfully used coalescing filter elements on motor reservoir breathers to prevent them from creating an oil film on the top of the motor.

You're saying there was no evidence of abnormal splashing where you looked? Maybe it might be worth to open that center port and look directly at the oil rings to see if they are bouncing erratically creating excess splash. My understanding is that 3600rpm machines would be more susceptible to this. Also incorrect oil setting can lead to oil ring bouncing (I guess that was why JJPellin had you check the oiler connection points). Also vib analysis might provide a hint on whether oil rings are steady or bouncing. Unfortunately it might be an intermittent problem though... tougher to solve.

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(2B)+(2B)' ?

 

[Stanley2113]

The oil ring was turning smoothly. The only abnormal splashing seen was the oil coming off of the radial bearing itself. I moved the breather to port that wasn't getting the splashing. I'm going to monitor for further leaking and oil level change.

 

[electricpete]

Ok, sorry I missed it the first time. Now I understand what you're saying better. The bearing was splashing and you moved the breather away from it.


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(2B)+(2B)' ?

 

[JJPellin]

Pete,

The Watchdog does not have atmospheric pressure above the oil in the oiler. It only uses half a pipe, so any pressure or vacuum above the oil level will be the same in the oiler as it is in the housing. We have hundreds of these installed with no breather and I have never seen a problem. Even if the change the OP made resolves the oil leak, I would still remove the breather to reduce contamination potential.

Johnny Pellin

 

[Stanley2113]

Removing the breather and just plugging the hole looks like the path we are going to take.

Thanks for the info about the watchdogs. I didn't know anything about them until I came to this site. My old site used the bulb tryco oilers.

Thanks for all the replies.

 

[electricpete]

Thanks JJPellin for explaining that. I was confusing it with a different type of oiler.

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(2B)+(2B)' ?