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To reduce soil-tool adhesion followed by an improvement in draft force, many attempts have been made on the surface modification of moldboard ploughs by applying plastic coatings to them. Like moldboards, furrowers may also show adherence to soil according to its physical condition. This research aimed at draft force improvement of furrowers using surface coatings. Due to the self-scouring ability and low frictional characteristics of ultra high molecular weight polyethylene (UHMW-PE), a narrow metal furrower has been coated with the plastic. For comparison, a steel tine equal in shape and dimension to the plastic-coated tine has been built. The tines were designed like the furrowers and were tested for draft force in a linear soil bin filled with heavy clay soil. Each experiment was repeated three times over a depth of 20 cm with two different compactions and gravimetric moisture content of 4% and 18% dry based. The average draft force value of the polythene coated tine was significantly lower at both moisture levels. In high compacted soil with 18% MC (gravimetric moisture content), the draft force of the UHMW-PE coated tine measured 29% less than that of the steel tine. In conclusion it has been found that the modification to the furrower tines by UHMW-PE coating can reduce draft force significantly.

Considering the necessity of using light weight, high strength and corrosion resistant materials, automotive and aerospace industries need to use advanced production technologies. Hydroforming has been regarded as one of the new technologies in forming of aluminium and magnesium alloys. These alloys have very low formability at room temperature which will be improved at elevated temperatures. In this paper, AA1050 aluminium alloy tube is numerically and experimentally investigated at different temperatures. Thickness distribution in forming zone is studied under different thermal conditions. Numerical results have been verified by experiments and there is a good agreement.

Organosolv pulping of bagasse was conducted following a central composite design using a two-level factorial plan involving three pulping variables (temperature: 190-210 degrees C, time: 120-180 min, organic solvent charge: 40-60% dimethyl formamide). Responses of pulp properties (yield and holocellulose, alpha-cellulose, kappa number, ash and ethanol-dichloromethane extractives contents) and the pH of the resulting wastewater to the process variables were analyzed using statistical software (MINITAB). Main factor analysis revealed that optimum pulp has the following characteristics: 82.7% (yield), 92.9 (kappa number), 95.84% (holocellulose), 83.53% (alpha-cellulose), 1.403% (ash), 2.562% (ethanol-dichloromethane extractives contents) and 6.39 (pH). These results showed that acceptable properties of pulps could be gained at 200-210 degrees C for 150 min and 40-60% DMF. Based on these results, this method could be used for pulping of bagasse equivalent NSSC concerning high yield at a fixed kappa number. In addition, bagasse could be pulped with ease to approximately 55% yield with a kappa number approximately 31. Numerical analyses showed that cooking temperature had the greatest influence on properties of obtained pulps within the DMF concentrations and cooking time as cooking variables.