Oil pressure issue Howden WRV255, stumped again

[Tycho]

Tycho,
In this post you indicate maag ng 70/70 pump on Howden 163 & is same pump on Howden 255, is that correct?
I guess speeds could be different, but they must like this model!

maag data sheet pretty vague & with 0 pressure across it & no viscosity of medium does not mean to much.

http://www.pumpfundamentals.com/pump...p-hydrolub.pdf

Viking pump selector not much equates to maag, except bigger or higher oil flows, so mystery.

http://tools.vikingpump.com/pumpsele...ectvalues.aspx

What does pump look like
http://www.spec-net.com.au/press/0509/kpa_130509.htm
http://generalpumpandmachinery.com/p...viking-al4195/

My hat of to you Ranger!!
f1f54d557cea8230d89ab11a47bad369.jpg

You really have attention to detail good sir!

I had a double take myself when I went back to my old post and saw that it was a maag NP70/70 pump on the WRV163 as well... because they are two different pumps completely

On the WRV 163 unit the pump looks like this:
maag7070.jpg
The system has three compressors, and during commissioning, two of the pumps seized within 4 hours of running. the third survived for two days.
The compressor package manufacturer sent us 2 new pumps to begin with, they also seized within a few hours.
They then sent us new bearings and rotors for the pumps, so we had to overhaul them on site, but after the overhaul, with a different kind of bearings they have been running for 10 years.
Personally I don't like them, first because of the breakdowns, second because they are noisy.
on this ship, the compressors are in the bow of the ship, and if we draw a straight line from the maneuvering bridge to the compressors, it's two decks down and the distance is perhaps 30 meters.
when I remote started the system from the bridge I could hear the oil pump going "NJEEEEEEEEEEEEE" and that's not the way it should be.

I've been all over google to find a maag pump that looks like the one installed on the WRV255 unit and haven't found anything in pictures or service manuals that looks anything remotely like it, on the plaque it says NP 70/70, that's all.
I have a printout of a user manual for all maag pumps, but it's very general and it doesn't show the model that is on the WRV 255 unit, so it's a lot of guesswork

The Viking pump on the old unit is indeed this type:
vikingpump.jpg

I serviced this one 2 years ago or so because the oil pressure was fluctuating slightly, it had dug slightly into the wall, but a lot of elbow grease and some fine tuning on the adjustment ring and it was back in action



Also, the compressor unit manufacturer has been bought by a US company, so not it's close to impossible to find out who to contact, and all inquiries has to go through "inquiries@....."