دراسة إجراء تعديلات على جهاز دينامومتر ميكانيكي محلي ونمذجتها واختبار أدائها

Abstract

This research was conducted in February 2025, in safita area, tortuous governorate, 300 meters above sea level. This research aims to make modifications to specifications of mechanical dynamometer which was previously designed in order to measure tensile force on hard soil using this device.

 This was done by making modifications on the main part of this device which is the tensile spring, the measuring is done according to its elongation during work.

 Two different spring wire diameters were used for two different types of spring materials, with each modification  resulting in anew spring.  these modifications were then modeled on Solid Work program by applying the calculate stresses at the studied working conditions, comparing the failure stress with the yield stress for each spring,and selecting the best one for these conditions.

Then, test the machine after each modification for measur the forces on three hulled plough on hard soil with moisture25, then, comparing the modeling and experimental results and  choose the best design that is agreed upon by the modeling and experimental .

 Both the experience and modeling results showed that as the diameter of wire-section gets taller and changed the type of material, that spring is made of, from ck67 to90Mnv8 ,the spring ability to withstand tensil forces is ingreased.

The elongation was greater at wire diameter 8 mm for both types of materials,and we saw failure stress,making it unsafe to operate, at diameter 12mm the elongation was lower, but the failure stress appeared for the first material and not for the second,so it is preferable.                                                                                       

When comparing the modeling results to practical results, in each case

 It was observed that the percentage of differences between the experimental and practical values in this case (diameter 12mm with the first type of material, 8diameter with the second type of material) was 11% and this percentage is considered high, but when using the diameter 12 mm and the second types of material, the percentage of differences between the practical and modelling values was 6% Therefore, the second type was the most appropriate design.