Metrology Equipment Catalog - Rapp Industrial Sales

A I R G AG E S Y S T E M S F O R D I A M E T E R M E A S U R E M E N TA I R G A G E S Y S T E M S F O R D I A M E T E R M E A S U R E M E N TNon-Contact Measuring with MERCERMERCER air gauging units and systems are mostly used for measuring cylindrical workpiecefeatures such as bores and shafts. Non-contact air gauging offers many advantages,among others:• All the measurements are taken with high reliability and repeatability is excellent sincethe sensors in the form of air plugs or air rings do not use any mechanical part for transmittingsignals.• Non-contact measurement eliminates the risk of damaging the workpiece surface.• Air pressure acts as a powerful cleaner at the measuring points, thus enabling the userto inspect even dirty, oiled and greased surfaces or those exposed to solid contaminant,securely.• Linear displaying of a number of signals is highly accurate with up to 10’000xmagnification.Air measures preciselyAir flowing through the plug from the gageunit escapes through two or more jets (1)directly on the surface to be measured (2).Any dimensional variation of the workpiececauses the clearance (3) between each jetand the workpiece to change. This leads toa difference in pressure, which is convertedusing the MERCER gauging units prior tobe measured.Air gauging general principles and applicationsare described hereafter along with allrelevant product features.1 Air jets2 Part surface3 ClearanceSafety use,speedy actionJet plug gages are used for boremeasurement while jet ring gages servefor shaft inspection. They are equippedwith a guiding cylinder which makes themself-centring into the part feature to bechecked. Inexperienced users and qualifiedstaff will both be convinced of the safetyuse and speedy action of air gaugingsystems.Air plugs and air rings are fitted with twojets lying 180° apart from one another.Since they work in sum measurement, boreand shaft diameters can be establishedthrough 2-point measurements.With the measurements taken at severalpoints, any variation in diameter can bedetected and, therefore, form and shapeerrors as well.1ø23DminD max.DDD DDWhen measuring ovality, both diametersdmax and dmin are captured, so that the circularityerror will match the difference, reducedby half, between both diameters.When measuring at several points, the meandiameter is captured, so that any circularityerror will not be detected through a 2-pointmeasurement.O-2Rapp Industrial Sales888 789-7277