Type a line (regrease D 110 mm B 27 mm) or fill in the fields: the line and the fields stay in step.
Enter the outside diameter D and the width B of a rolling bearing of a motor, pump or fan, and the calculator gives the grease to add when it is relubricated: in grams and ounces, and with the density of the grease in cm3. With the grams one grease gun stroke delivers it gives the number of strokes, and with the bore d and the shaft speed n the mean diameter dm and the speed factor n x dm. It shows the working with your numbers, draws a section of the bearing with D, d and B, and gives a line you can copy or add to a request.
D and B come from the bearing or its catalogue: the calculator does not look dimensions up from a designation and publishes no catalogue dimensions. Where the bearing or machine maker’s instructions give a quantity, use that one. No relubrication intervals, no n x dm limit values and no grease recommendations.
Gp = 0.005 x D x B, with Gp in grams and the outside diameter D and the width B of the bearing in mm. It is the grease commonly added at each relubrication, the replenishment quantity. With D 110 mm and B 27 mm: 0.005 x 110 x 27 = 14.85 g, or 14.85 / 28.349523125 = 0.524 oz.
Strokes = Gp / grams per stroke. Gun output varies from gun to gun, so there is no default figure: weigh a few strokes of your gun and divide by their number. If a stroke gives 1.5 g, 14.85 / 1.5 = 9.9 strokes. For the volume in cm3, Gp is divided by the density from the grease data sheet.
The mean diameter dm = (d + D) / 2, and the speed factor is n x dm in mm/min with n in r/min. With d 100 mm, D 200 mm and 1500 r/min: dm = 150 mm and n x dm = 225 000 mm/min. Relubrication interval charts and grease data sheets use this factor; no limit values here.
| Quantity | Relation | Note |
|---|---|---|
| Grease to add | Gp = 0.005 x D x B | g; D the outside diameter and B the width, in mm; the grease commonly added at each relubrication |
| Inches | 1 in = 25.4 mm | D, B and d are converted to mm first |
| Ounces | 1 oz = 28.349523125 g | 1/16 of a pound |
| Volume | V = Gp / density | cm3; the density in g/cm3 from the grease data sheet, no default |
| Gun strokes | Gp / grams per stroke | the grams per stroke weighed on the gun in use |
| Mean diameter | dm = (d + D) / 2 | mm |
| Speed factor | n x dm | mm/min; n in r/min; no limit values |
Inch dimensions are converted to mm before the working. Gp is the grease commonly added at each relubrication; the first fill of a new bearing or housing is not worked out here.
The relation Gp = 0.005 x D x B (g, mm) is given as the grease added at each relubrication in independent publications on machine lubrication and in a lubricant maker’s reference data, also as 0.114 x D x B in ounces with D and B in inches; the calculator converts the units itself. That gun output varies and a stroke should be weighed is described in two independent maintenance publications. The definition dm = (d + D) / 2 and the speed factor n x dm in mm/min follow two independent publications on equipment reliability and lubrication. The inch and the ounce follow their definitions, 25.4 mm and 1/16 of a pound (0.45359237 kg).
From the outside diameter D and the width B of the bearing: Gp = 0.005 x D x B, with Gp in grams and D and B in mm. It is the grease commonly added at each relubrication, the replenishment quantity. A bearing with D 110 mm and B 27 mm takes 0.005 x 110 x 27 = 14.85 g, about 0.524 oz.
The calculator does not look dimensions up from a designation, and the site publishes no catalogue dimensions. Read the outside diameter D and the width B from the bearing, its box or its catalogue and type them in. What the designation itself means, its type, bore and suffixes, is explained by the bearing designation reader.
The number of strokes is the grease quantity divided by the grams one stroke delivers. Gun output varies from gun to gun, so the calculator has no default figure: weigh a few strokes of the gun in use and divide by their number. If a weighed stroke gives 1.5 g, a bearing with D 110 mm and B 27 mm takes 14.85 / 1.5 = 9.9 strokes.
Where the bearing or machine maker’s instructions give a quantity, use that one. The calculator gives the quantity commonly added at each relubrication, worked out from D and B, for when no such figure is at hand.
dm = (d + D) / 2 is the mean diameter of the bearing, from the bore d and the outside diameter D. n x dm, the shaft speed in r/min times dm in mm, is the speed factor in mm/min that relubrication interval charts and grease data sheets use. With d 100 mm, D 200 mm and 1500 r/min: dm = 150 mm and n x dm = 225 000 mm/min. The calculator gives no limit values and no intervals.
D, B and d in mm or inches (1 in = 25.4 mm); the result in grams and ounces (1 oz = 28.349523125 g), and in cm3 when the density of the grease is entered in g/cm3, as there is no default density; the shaft speed in r/min; the gun output in grams or ounces per stroke. In the line, the outside diameter is marked D, the width B and the bore d, or the size is written d x D x B.
The calculator gives the grease to add. When bearings, grease nipples or parts of the bearing housing are needed, send the line from the calculator with the bearing designation and a photograph of the machine nameplate, and Vessel Core checks the details before an offer goes back.
