Problems Mechanical Seal, HOWDEN 255 130 MK5, Amonia.

[REEFERMAN CR.]

I have problems with a mechanical seal 255 130 HOWDEN MK5, a leak was reported median mechanical seal oil in the original stamp ... Register ... But by changing the internal parts that the labyrinth seal note, 2 of his 3 threads for the extraction are problems, 1 of those shows that thread a piece of screw is stuck, and solved by welding a piece of .... screw apart the front of the labyrinth seal is too ..... can not be beaten remove the labyrinth seal and only 1 thread extraction is abilites ... and thus their extraction is very difficult couple! Always replace the seal antiguoi which was in their faces working in good condition. But the acts since he began to run the compressor mechanical seal started to leak oil again ... The compressor is usually at 4 "Hg SETPOINT.
I believe that if you previously hit the labyrinth seal and welded part of a screw in threaded extarccion ... oring seal the labyrinth may have been burned or cut, and the mechanical seal because he twisted metal solder may tend to warp.
Another observation would be that if you change the labyrinth seal, mechanical seal and teflon washer .... just detars of all these parts .. is the oil drain hole in the area of ​​mechanical seal ....
... NH3 Compressor operates with some experience with a similar problem .... any expert HOWDEN?

Thank you.

[RANGER1]

REEFERMAN,
I have looked at this post a few times & are not sure what you would like to know?

If you have replaced all "0" rings & seal faces look OK, also polished shaft seal journal, there
is not much else you can do except instal new seal if it leaks.

Not sure what you have done with labryrinth seal, as you normally don't have to do anything with it.

How many hours are on compressor since last overhal?

[REEFERMAN CR.]

Ranger 1

What happens is that it was reported that the mechanical seal had changed 2 years ago and since I had changed this .. stay with problems since it is throwing oil on the drain hole.

I request the new seal, I went to the ground and when I was dismantling the old seal, note the badly beaten labyrinth seal with a screw and a soldier in one of the threads for extraction.

I have HOWDEN literature and photographs ... so that the exit hole Lube oil drain ... only because the mechanical seal faces are bad .... or teflon washer that is behind the stationary seal be broken ... one of two ways you can reach the oil drain hole.

It is very strange ... it is very simple, remove the old mechanical seal, shaft cleaning, inspection of other parts ... and go.

but a lot of oil seal is voting ..

One detail, the compressor 4 "Hg suction, pressure oil is 218psig.

I appreciate the comment.

[Magoo]

Have you done a coupling alignment check. Mis-alignment will damage the rotating carbon face, thrusting will also damage seal faces and wedge seals.
On the older Howdens the oil diff pressure was 35 psig above discharge. What is your discharge /high side gauge pressure.

[Josip]

Hi, REEFERMAN CR

Ranger 1

What happens is that it was reported that the mechanical seal had changed 2 years ago and since I had changed this .. stay with problems since it is throwing oil on the drain hole.

I request the new seal, I went to the ground and when I was dismantling the old seal, note the badly beaten labyrinth seal with a screw and a soldier in one of the threads for extraction.

I have HOWDEN literature and photographs ... so that the exit hole Lube oil drain ... only because the mechanical seal faces are bad .... or teflon washer that is behind the stationary seal be broken ... one of two ways you can reach the oil drain hole.

It is very strange ... it is very simple, remove the old mechanical seal, shaft cleaning, inspection of other parts ... and go.

but a lot of oil seal is voting ..

One detail, the compressor 4 "Hg suction, pressure oil is 218psig.

I appreciate the comment.

Some amount of oil must come out through the oil drain hole. You do not use a dry shaft seal. Maybe you can measure quantity of drain oil within some time i.e. a week time.

If you install a new shaft seal everything should be OK, but if you have a shaft scratched then you can have a leak .... sometimes with Howden there is a problem with O-ring too.

Best regards, Josip

[RANGER1]

REEFERMAN,
Without seeing labyrinth its hard to determine exact problem.
Also keep in mind that shaft seal cover has to torqued up correctly as it is very low setting.
Do not have manual with me but it could only be 20 NM.

If to tight it may split teflon.

[REEFERMAN CR.]

Hello All
Thank you very much for your good comments!

Compressor operating hours 23,357 hours:

The amount of oil leaving the oil drain hole, the mechanical seal is way too: 40 drops in 60 seconds ... is great ... HOWDEN recommended at least 6 to 8 drops according to technical service manual.

In fact if you install the mechanical seal dry their faces! Do not use oil in the cars of the mechanical seal ...

I did not make angular and parallel alignment.

I am aware that the labyrinth seal should not cause problems with oil leaks ... but ... This labyrinth seal is very hurt and not if a certain deflection, and torque when the mechanical seal cover , the quote is not even and all the other parts do not work well.

The compressor works with a suction 4 "hg, discharge pressure of 175 to 180 psig and pressure of 220 psig oil, AL495 Viking oil pump, pressure regulator valve oil differential A4AL precion 30psig PARKER ... ...

220PSIg the house of the mechanical seal ...

Friends, I have decided to disassemble the mechanical seal and the seal is new, the area where the shaft mechanical seal is located does not present major scratch ... and no shock in these areas ...

Will review the alignment of the compressor - electric motor.

Any comments were agradesco.

Greetings.

[RANGER1]

REEFERMAN,
Not sure if I understand 100% but best to lubricate seal faces , "0" rings atc with new, clean refrigeration oil.
Also look for any damage to "seal housing". By this I mean lumps, bumps, high spots on faces, as this will prevent seal from sitting square to compressor body.
Torque up seal cover evenly & to correct torque.

note (The teflon gasket should be between seal cover & steel face)

Good luck

[Carlos Barrantes]

Dear friend,

It is paradoxical but you have a problem with lubrication .
Mechanical Seal not to be circulating enough oil for cooling and removal of particles.
His case is familiar. The last case I had a XRV127R1 Howden.
Oil leakage , verification of alignment , change the seal again and again. . . the problem : plugging in the Oil Tubing that goes to the Seal caused by the cuts in the ends of the tube with a tube-cutter poor .

[RANGER1]

REEFERMAN,
Not sure if I understand 100% but best to lubricate seal faces , "0" rings atc with new, clean refrigeration oil.
Also look for any damage to "seal housing". By this I mean lumps, bumps, high spots on faces, as this will prevent seal from sitting square to compressor body.
Torque up seal cover evenly & to correct torque.

note (The teflon gasket should be between seal cover & steel face)

Good luck

Correction, new type seal has no teflon gasket but has "0" ring in stationary face which seals against
seal cover.