Extensometer MFA 20

The extensometer MFA 20 is suitable for determining the yield point and uniform deformation for test samples above 4 mm diameter and 15 mm width. The MFA 20 consists of two casing halves which moveparallel and easily towards each other on play-free guidancebars. The upper casing overlaps the lower casing for the totalextension so that the parallel guide and the measuringsystem are protected from damage and dust. A measuringspring with a temperature compensated full bridge straingauge serves as the measuring system for the MFA 20. Theknife edge holders and the clamping device can bepositioned easily by loosening just one knurled screw.Alignment pins fix them in their exact position.In order to achieve a symmetrical position of the counterrollers with respect to the knife edges, the counter rollerfixture can be turned and the clamping device shifted inthree steps.The initial gauge length can be adjusted up to 140 mm withthe upper extension arm and up to 200 mm with both theupper and lower extension arms in steps of 10 mm. Evenintermediate lengths like e.g. 55 to 195 mm may beobtained by additional shifting of the upper and lower knifeedges.Opening width and clamping force are continuallyadjustable. For initial gauge lengths greater than 100 mmthe holder which belongs to the extension arm and has thegreater distance between the counter rollers must be used.The casing is made of a high strength aluminium alloy andhas a long lasting and scratch-resistant hard anodizedsurface. For the small parts argent tan and stainless steelare used. The round knife edges can be utilized along theentire perimeter by rotating them. Thereby a longer lifetimeis achieved.