Calculating Grease Quantity, Frequency

Calculator with the word 'grease' displaying across the screen.

Use this handy calculator as a general guideline for establishing grease frequency and volume in bearings. If you need help creating precision calculations for your equipment, consider contacting a Noria lubication expert to help you get started.

  • Ball: Round ball rolling elements.
  • Cylindrical/Needle: Rolling elements that are cylindrical or needle like in their geometry.
  • Tapered/Spherical: Rolling elements that are tapered or spherical in their geometry.
  • Journal Bearing: Standard plain, babbitt, sleeve or journal bearing.”]); descriptions.push([“Particle Contamination”, “
    • Light, non-abrasive: Airborne contaminants that are considered non-abrasive (lime, flour, etc.) that settles on equipment over time. Takes months to show up. Example: equipment inside climate controlled room.
    • Heavy, non-Abrasive: Airborne contaminants that are considered non-abrasive (lime, flour, etc.) that readily settles on the equipment.
    • Light, Abrasive: Airborne contaminants that are considered abrasive (silica, sand, etc.) that settles on the equipment over time. Takes months to show up. Example: normal outside conditions.
    • Heavy, Abrasive: Airborne contaminants that are considered abrasive (silica, sand, etc.) that readily settles on the equipment.”]); descriptions.push([“Moisture”, “
      • <80% Humidity: Very low humidity and little to no likelihood of water being ingressed into the equipment.
      • 80-90% Humidity: Normal amounts of humidity and little to no likelihood of water being ingressed into the equipment.
      • Occasional Condensation: Areas outside that may get rained on or have large temperature swings that can cause condensation.
      • Heavy Water: Areas that are prone to washdown or other constant sources of water ingression.”]); descriptions.push([“Vibration”, “
        • <0.2 ips: Little to no machine vibration.
        • 0.2-0.4 ips: Moderate vibration.
        • >0.4 ips: Severe vibration.”]); descriptions.push([“Position”, “
          • Horizontal: The shaft of the component is level to the ground and horizontal.
          • Vertical: The shaft of the component is perpendicular to the ground and vertical.
          • 45° Angle: The shaft of the component is at a 45° angle in reference to the ground.”]); descriptions.push([“Sizing Source”, “
            • Bearing Size: The actual bearing was measured.
            • Housing Size: The housing that the bearing sits in was measured.”]); function showDescription(index) { var details = descriptions[index]; $(“#tooltipModalTitle”).html(details[0]); $(“#tooltipModalText”).html(details[1]); $(‘#tooltipModal’).modal({ backdrop: true, keyboard: true }); } ]]>

  • Grease Volume and Frequency Calculator

    Sizing Source

    Make SelectionBearing SizeHousing Size

    Bearing Type:

    Make SelectionBallCylindrical/NeedleTapered/SphericalJournal Bearing

    Make Selection< 125°F (51.7°C)125°F (51.7°C) - 150°F (65.6°C)150°F (65.6°C) - 175°F (79.4°C)175°F (79.4°C) - 200°F (93.3°C)> 200°F (93.3°C)

    Particle Contamination:

    Make SelectionLight, non-AbrasiveHeavy, non-AbrasiveLight, AbrasiveHeavy, Abrasive

    Moisture:

    Make Selection< 80% Humidity80-90% HumidityOccasional CondensationHeavy Water

    Vibration:

    Make Selection< 0.2 ips0.2-0.4 ips> 0.4 ips

    Position:

    Make SelectionHorizontalVertical45° Angle

    The values calculated are based on the data that is input and may not reflect actual in-service environments. To increase the accuracy of regrease volumes and frequencies we recommend the use of condition-based tools such as grease analysis and ultrasound.

    How to Use This Grease Calculator

    To calculate grease quantity, you need the bearing’s physical dimensions (primarily the outside diameter and width). Once you have these two measurements (in inches), you multiply them together and then multiply by 0.114. The resulting answer is the grease quantity in ounces.

    This formula can be used with metric measurements as well; just use 0.005 instead of 0.114. The result will be grease quantity in grams. This formula works for all bearings and is widely accepted as the best way to calculate grease quantity.

    Once the required grease volume has been calculated, you will need to determine how often to apply that amount of grease. This timeframe is known as the regreasing frequency. This calculation is more complex. The machine’s operating conditions must be collected along with some additional bearing information.

    Temperature is known to affect both grease and oil, so naturally one of the first correcting factors that must be collected is operating temperature. The hotter the environment, the more frequently the grease must be replenished. The ambient contamination (how dusty the environment is) and moisture (how humid the environment is) work in a similar manner. The dirtier and wetter the environment, the more often the bearing must be regreased.

    Simple things like the bearing’s physical position and vibration will also affect the grease’s run-out and frequency of reapplication. If the bearing is mounted on a vertical shaft, the grease has a tendency to run out of the bearing quicker, thus needing to be replenished more often.

    When the bearing is subjected to vibration, it causes the oil in the grease to separate from the thickener, allowing it to drain away from where it is needed much faster. Therefore, these two correcting factors — position and vibration — should be taken into consideration.

    The final correcting factor is that of the bearing element shape. This is important because each different element stresses the grease differently. For instance, a ball rolling across the race churns the grease differently than a spherical element, which churns the grease much more heavily.

    Below is a chart of these correcting factors and how they operate together. Once they have been calculated properly, the final pieces of t
    he puzzle are the bearing ID and speed of rotation. Through some simple math, you are left with a run-time (in hours) frequency for regreasing.

    Once you know the proper amount and frequency to use, be sure you are also using the proper regreasing procedures to apply the grease to the right place in the right amount at the right time.

     

    Grease calculation formulat

    Subscribe to Machinery Lubrication



    Source

    Leave a Reply