Silver bearings outside case

Our Mobil Rarus™ 400 Series ashless air compressor oils are designed for compressor systems employing gears and bearings, and are highly recommended for crankcases. They are formulated with high-quality mineral base oils and a high-performance additive system to provide exceptional equipment protection and reliability for compressors operating under mild to severe conditions. 

Mobil Rarus 400 Series air compressor oils can result in cleaner compressors and lower deposits compared to conventional mineral oils, resulting in: 

  • Longer running periods between maintenance intervals
  • Improved valve performance
  • Lower maintenance costs

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Technical resources

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Features and Benefits

The use of the Mobil Rarus 400 Series oils can result in cleaner compressors and lower deposits compared to conventional mineral oils, resulting in longer running periods between maintenance intervals. Their excellent oxidation and thermal stability safely allow extended life capability while controlling sludge and deposit formation. They possess outstanding anti-wear and corrosion protection, which enhances equipment life and performance.

 

Features

Advantages and Potential Benefits

Low Ash and Carbon Formation

Improved valve performance

Reduced deposits in discharge lines

Reduced potential for fires and explosions in discharge systems

Improved compressor performance

Outstanding Oxidation and Thermal Stability

Longer oil life

Improved filter life

Lower maintenance costs

High Load-carrying ability

Reduced wear of rings, cylinders, bearings and gears

Excellent Water Separability

Less carryover to downstream equipment

Reduced sludge formation in crankcases and discharge lines

Reduced blockage of coalescers

Less potential for emulsion formation

Effective Rust and Corrosion Protection

Improved protection of valves and reduced wear of rings and cylinders

 

Applications

The Mobil Rarus 400 Series oils are recommended for single and multistage air compressors. They are particularly effective for continuous high temperature operation. The maximum compressed air temperature, according to DIN 51506, is 220 °C. They are suitable for reciprocating and rotary type machines with the lower viscosity grades mainly used in rotary compressors. Rarus 400 Series oils are recommended for units with a history of excess oil degradation, poor valve performance or deposit formation. They are compatible with all metals used in compressor construction and with mineral-oil compatible elastomers used in seals, O-rings and gaskets.

 

Mobil Rarus 400 Series oils are not intended or recommended for use in air compressors for breathing applications.

 

The following types of compressors have shown excellent performance with the Mobil Rarus 400 Series oils:

     •  Reciprocating air compressor crankcases and cylinders

     •  Rotary screw compressors

     •  Rotary vane compressors

     •  Axial and centrifugal compressors

     •  Compressor systems with critical gears and bearings

     •  Compressors used in stationary and mobile applications

 

Specifications and Approvals

This product meets or exceeds the requirements of:

424

425

426

427

429

DIN 51506:1985-09 VDL

X

X

X

X

X

 

Properties and Specifications

Property

424

425

426

427

429

Grade

ISO 32

ISO 46

ISO 68

ISO 100

ISO 150

Ash, Sulfated, mass%, ASTM D874

‹0.01

<0.01

<0.01

<0.01

<0.01

Copper Strip Corrosion, 3 h, 100 C, Rating, ASTM D130

1B

1B

1A

1B

1A

Density @ 15 C, kg/l, ASTM D1298

0.866

0.873

0.877

0.879

0.866

FZG Scuffing, Fail Load Stage, A/8.3/90, ISO 14635-1

12

11

12

11

11

Flash Point, Cleveland Open Cup, °C, ASTM D92

236

238

251

264

269

Foam, Sequence I, Stability, ml, ASTM D892

0

0

0

0

20

Foam, Sequence I, Tendency, ml, ASTM D892

10

20

0

30

430

Kinematic Viscosity @ 100 C, mm2/s, ASTM D445

5.4

6.9

8.9

11.6

14.7

Kinematic Viscosity @ 40 C, mm2/s, ASTM D445

32

46

68

104.6

147.3

Rust Characteristics, Procedure A, ASTM D665

PASS

PASS

PASS

Rust Characteristics, Procedure B, Rating, ASTM D665

PASS

PASS

PASS

Rust Prevention, Procedure B, Rating, ASTM D665

PASS

PASS

Viscosity Index, ASTM D2270

105

105

105

100

100

 

Health and Safety

Health and Safety recommendations for this product can be found on the Material Safety Data Sheet (MSDS) @ http://www.msds.exxonmobil.com/psims/psims.aspx