ORID O-Ring Identifier to Test the Following Materials EPDM / Nitrile / Kalrez / FKM

O-Ring Material Identifier: The ORID MID 70 is a practical and useful tool to eliminate the chance of error in selecting an O-Ring Seal without destroying the O-Ring.
Benefits: The O-Ring tester can be used to identify mislabelled, new, damaged O-Rings or when sorting out O-Rings.
Please note: O-Ring tester may not give the correct reading on o-rings which has been used in a high temperature environment for a long period of time.

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INSTRUCTIONS FOR THE MID 70 MODEL COMPARATIVE TESTER

WHERE AND WHEN TO USE

• 1. To differentiate between known O-Rings
• 2. To check for mislabelled O-Rings
• 3. To verify new O-Rings
• 4. Sorting Applications

YOUR ORID MID 70 IS CALIBRATED FOR:

• 1. 70-Durometer O-Rings
  70-Durometer rubber is the most popular O-Ring used in industry. Your ORID MID 70 will accurately read 60, 70 or 80-Durometer O-Rings
• 2. O-Rings within their rated shelf life
• 3. 100, 200, 300, 400 series O-Rings (Cross section 103" to 275" or 2.62mm to 6.99mm)

HOW TO TAKE READINGS
Hold the ORID MID 70 in a vertical position so that the straight edge of the sliding weight hangs out the bottom of the steel tube. It is best to rotate the tube so that the sliding weight handle can be seen on the side of the ORID MID 70. The straight edge of the sliding weight should fall directly upon the O-Ring cross section so that the edge bounces off the arc of the cross section.

Raise the sliding weight by the handle until the handle contacts the top of the vertical groove of the tube. Release the handle allowing the sliding weight to drop. Notice theheight of the first rebound only. This is your reading. Take as many readings as necessary.

Compare the height of the first rebound to the corresponding marks on the tube. If the first rebound rises up to the highest set of marks on the ORID tube, it indicates an Ethylene Propylene O-Ring reading. The second highest set of marks indicates a Nitrite or Buna O-Ring reading. The third set of marks indicates a Perfluoroelastomer O-Ring reading, also known as Kalrez. The lowest set of marks on the ORID MID 70 tube indicates a Fluorocarbon O-Ring reading also known as FKM.

The surface upon which the O-Rings are being tested will also affect the rebound height of the sliding weight. An ideal surface would be the corner of a steel table on a cement floor, ground level. However, accurate readings can be obtained on wooden desks well settled onto carpeted floors. Beware of desk padding and poorly supported surfaces or any surface or factor that would absorb any of the energy of the sliding weight.

WARNING - DO NOT USE THE ORID MID 70:

• 1. To identify or analyze a failed O-Ring
• 2. On damaged O-Rings
• 3. On O-Rings of unknown composition
• 4. On out-of-date O-Rings
• 5. On O-Rings less than 100 series or greater than 400 series cross sections
• 6. To identify composition of flat gasket surfaces
• 7. On other than 60, 70 or 80-Durometer O-Rings

Readings on any of the above may not be accurate. If it is necessary to identify O-Rings that all into the category of Numbers 5, 6 and 7 above, please consult the factory. Other models are available.

See diagrams: Please click on technical tab