10 EE lubricants

texasgunsmith said:

...
Here's a nice post by Joe Michaels where he prefers the hydraulic DTE's:
DTE Numbered and DTE Named Oils - The differences explained
...

Click to expand...

Joe Michaels said:

...
Having spent 47 years in the powerplant industry, and working with all sorts of babbitted, bronze, and antifriction bearings, I got a little familiar with lubricating oils. In the hydroelectric plants, we had babbitted bearings on the turbines and generators. 800 tons of rotating mass in each unit, riding on babbitted thrust shoes and babbitted guide bearings. All of this ran in DTE 68 oil. We had Woodward governors using very sensitive hydraulic control valves, and ran DTE 46 in them.
...

Click to expand...

Cal Haines said:

Here's what I recommend:

• Mobil DTE Light for headstock bearings
• Mobil DTE Heavy-Medium for headstock center reservoir, quick-change gearbox and backgear
• Mobil Vactra #2 for apron and tailstock

...
Mobil DTE 24 DOES NOT replace Mobil DTE Light
Mobil DTE 26 DOES NOT replace Mobil DTE Heavy-Medium

The Mobil DTE 20 series (which includes DTE 24 and DTE 26) are "hydraulic oils", designed for very different service than the Mobil DTE Named series (including DTE Light and DTE Heavy-Medium), which are classified as "circulating oils".

Hydraulic oils need to be able to work with high-pressure pumps and exotic alloys used in servo valves, seals, etc. They have additives that are ENGINEERED for that application. In general, hydraulic systems use filters to remove contaminants and hydraulic oils have additives to suspend particles so that the filter can remove them. Their PRIMARY purpose is to operate hydraulic cylinders, etc, not lubricate gears and ball bearings. The BEST additives (including rust and oxidation and anti-foaming additives) for gears and ball bearings may not play nicely the alloys used in high-end hydraulic systems (and we're not talking your garden tractor here).
...

Click to expand...

Cal Haines said:

... The Vactra Named Series was discontinued and the DTE Named Series is the recommended replacement.

The DTE 20 series, which includes DTE 24, is formulated as hydraulic oil. The main purpose of hydraulic oil is to move things via hydraulic force, be it the cylinder on a backhoe or an industrial robot. According to the Exxon-Mobil website, the 20 series “…were developed in conjunction with the major builders to meet the stringent requirements of severe hydraulic systems using high pressure, high output pumps as well as handling the critical requirements of other hydraulic system components such as close clearance servo-valves and the high accuracy numerically controlled (NC) machine tools.” The two companies they mention by name are Denison (a Parker Company) and Vickers (an Eaton Company); both market high end hydraulic cylinders, servo valves, etc. These components use special alloys that require protection by special additives in the oil. The NC machine tools they referr to here are probably things like industrial robots, not CNC machining centers.

Hydraulic oil has to operate in very different conditions than gear oil and has special additives to handle the service. For example, a retracting hydraulic cylinder carries minute amounts of contaminants back into the cylinder where it can contaminate the oil; special additives work to neutralize the contamination. Hydraulic systems usually have filters to remove particles from the oil and this typically means that additives are used to suspend the particles until they reach the filter.

Additives aren’t necessarily compatible with one another and may work at cross purposes. For example, the additives in DTE 24 inhibit it's ability to separate from water; DTE Light, on the other hand, has excellent water separation properties.

I’m sure DTE 24 is dandy for what it’s designed to do: operate under pressure and protect internal hydraulic components with exotic metallurgy. It has special anti-wear additives designed to meet those needs.

DTE Light is better at other things: better anti-foaming, much better water separation, better rust and oxidation protection. Foaming can definitely be a problem with a high speed spindle bearing, i.e. 10EE running at 4000 RPM.

For a machine tool spindle with no circulating pump and filter to clean the oil, the last thing you want is oil designed to suspend particles; you want the particles to settle harmlessly to the bottom of the sump. You also want water to separate completely. You don’t want water and debris constantly circulating though precision bearings.
...

Click to expand...

AlfaGTA said:

OK, have to assume that this has been covered to death, but for the life of me i can't seem to make the "search" function cough up any relevant information.

Click to expand...