Introducing the standard version of the original Fisher Dip Type Cup, with all the advantages associated with a precision laboratory stand cup.

The orifices are of the readily replaceable type permiting coverage of the complete viscosity range with one cup and interchangeable orifices. The orifice may be readily replaced if damaged rather than requiring replacement of the entire cup.

• The Fisher series of viscosity cups as originally designed and produced, provided some advantages over other existing standard type viscosity cups. They accommodated a larger sample of the test material. The orifice was considerably longer than Its diameter resulting in cup efflux time more closely proportional to viscosity. However, there were deficiencies in the design. The cup was difficult to clean. It was costly to produce and to calibrate. A damaged or enlarged orifice resulted in necessity for replacement of the entire cup.
  
  
• The Gardco/Fisher Standard Viscosity cups retain the internal cup dimensions and the orifice and diameter. The orifices are of the readily replaceable type permitting coverage of the complete viscosity range with one cup and interchangeable orifices. The orifice may be easily replaced if damaged, rather than requiring replacement of the entire cup. The cups are furnished with conversion formulas and a table which relates the nearest tenth of a second of total efflux time to viscosity in centistokes. This table Is particularly useful In determining efflux time in seconds when viscosity in centistokes is known.
  
  
• The Gardco/Flsher Standard Viscosity cups are calibrated at time of manufacture to within 2% of target efflux time. This calibration is with standard oils traceable to the National Institute of Standards and Technology. At an additional cost, any cup/orifice combination is available with a CERTIFICATE OF CALIBRATION. The procedures and conditions of calibration on which the certificate is based qualify under ANSI/NCSL Z540-1 or MIL-STD-45662A, as applicable, & conforms to ISO 9000 requirements when certified.
  
  
• The Gardco/Fisher Standard cups are produced to very close mechanical tolerance with state of the art equipment. Such equipment not only insures that each cup Is correctly produced but also that all cups are identical. All parts of the cup are of stainless steel except for the orifice. The following table provides operating range specifications and the graph with the included mathematical formula that defines the flow characteristics for the cup/ orifice combination.

The body of the cup is machined from solid bar stock stainless steel. Note the conical opening for the orifice which permits gentle "tapping in" or "tapping out" of the orifice.

The orifices for the Cup are machined from brass with the exact conical exterior to match the opening in the base of the cup. Positive orifice identification is assisted by "steps" at the base of the orifice.

1. Adjust the sample to measuring temperature, usually 25° C (77°F).
   
   
2. Select the cup that will provide readings which are well within the cup range.
   
   
3. Make sure that the cup is clean, and place it in it's support.
   
   
4. Make sure that the cup Is level.
   
   
5. Place a finger under the cup orifice and fill the cup with bubble free test material. The cup is full when the meniscus disappears where the liquid joins the sidewall of the cup. If the cup is overfilled, scrape the excess into the cup well with a spatula or by passing the cover plate across the top of the cup. Note that the finger can be removed from the orifice when the cover plate is in place.
   
   
6. Start a timer as the cover plate is removed from the cup.
   
   
7. DetermIne the temperature of the efflux stream. If there is a significant change during the test it should be repeated.
   
   
8. Stop the timer at the first break in the efflux stream, one or two inches below the orifice.
   
   
9. Record the cup type and number, measured temperature and efflux time. For best accuracy, average three or more readings.
   
   
10. Promptly clean the cup, giving special care to the orifice.

Flow characteristics of the Gardco/Fisher Slandard viscosity cups are accurately defined by mathematical formula relating them to the viscosity of standard oils which are Traceable to the National Institute of Standards and Technology (NIST). The formula for each cup is shown on the cup graph.

For convenience, the formula for each cup has been solved for each tenth of a second within the normal cup range. Results are available in table form as shown at the left and are furnished with each cup.

Use the above table as follows: Assume an efflux time of 44.5 seconds. Read down the left column to the 44.0 second line and then to the right on this line to the 0.5 column. The value at the intersection is 33.9 centistokes. The tables may be read in reverse to find efflux time In seconds from a known centistoke value.

Note that conversion values are accurate only for those materIals that do not deviate greatly from true liquIds.