Motor grease and more

[spc6000]

I would like to ask as a student who want to learn chemistry.

Since I started, I've been thinking that most of high temperature and friction grease can be applicable to motor lubrication. Some guy spoke that I should use a grease specialized motor lubrication such as Polyrex EM of ESSO.
I wonder what is difference practically in performance.

One more...

I have 12 years old building and took over the maintenance contract recently. When I was doing inspection, I opened inline filter housing of closed heating loop water and found that it was almost black in color; filter was replaced only two days ago. So, I looked drain water. It contains black particles which looks like black coffee. I looked the chemical company service mothly report; sulfide supplied to the system on monthly basis. On the other, site handyman who have been working for 10 years insists that it should be no problem and no matter when he looked the filter, its color was same.
It does not look good to me.

[hvac3901]

I would say the grease is good regardless, just some pointers.

1. don't mix nlgi-1 and nlgi-2 the bonding agents or the detergant in the synthetic can cause breakdown in the grease and basically void any future grease additions.

2. don't mix any greases anyway, stick with the same grease forever and ever.

3. match the grease to the application. so read about the grease you want and determine if its apropriate.

4. excessive bearing pressure can lean and probably will to premature failure. dont squezze it until the grease comes out. leave the seals where they belong and replace it when it fails.

[snipe70e]

On a closed loop system chemicals should not have to be assed on a monthly basis unless there is a problem, usually a leak.
You said that sulfide is being used in the system. I have never heard of using SO2 as a chemical treatment so I am not sure what is being done here.

A normal treatment is nitrite for O2 removal and some form of phosphate for scale.

It sounds like the closed loop may need to be flushed.

[mdp]

Depending on the type/age of closed system you have removal of the iron oxide (the black stuff that discolors the water) may be impossible. Old systems that don't have an air seperator as compared to a compression tank/ air eliminator system will always turn the water black as the entrained air in the water oxidizes the iron piping. Newer systems with an air seperator don't have this problem. On an old system once the air attacks the iron piping it does no harm other than to discolor the water, keep the ph right and have periodic water analysis as a preventive measure.

[bmbradley]

Snipe70e is correct with the nitrite for the closed cooling
or heating systems. If the water is black you could have
anerobic bacteria in the system that will eat the nitrite
in the system. Check with your chemical treatment rep. and
they can provide a special kit to test for this bacteria.
You should also record the systems conductivity. If the reading is close to city water conductivity you have water loss in the system and this must be adressed first or you will be wasting chemical.

To clean the system you could purchase a 40 micron filter from Grainger and "side stream" the pump. This will help in cleaning the system also. Add pressure gauges before and after the filter so you can determine when it is fouled.

[spc6000]

I would like to appreciate your wisdom. The "sulfide" is actually "sulfite". But it still not make sense. It is usually used only in steam boiler plant.

Have a nice day and weekend is just around cornor.

[orland25]

hi; First;example; take the bearing decibels noise,that is your north to begin.EXAMPLE you goes the first time and the measure in decibels is 34 decibels noise.Then you put a little bit of grease,and the decibels noise goes down to 22 decibels noise. Then you goes in one or two months and the decibels noise continue in 22,or 24 You do not have to put any grease. BUT if you find the bearing in 34 decibels or more,and you put a little bit of grease again and not goes down in decibels,CHANGE THE BEARING maybe you think is good,but first you need the tool.