จำนวน Repository ( 5 )

การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ โครงการวิจัยย่อยที่ 1 เครื่องทดสอบจุดศูนย์กลางมวลสำหรับรถยนต์
การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ โครงการวิจัยย่อยที่ 1 เครื่องทดสอบจุดศูนย์กลางมวลสำหรับรถยนต์

The aim of this research is to create the center of mass testing machine for vehicles with maximum mass 3000 kilograms. By the performance of this machine is able to determine the center of mass 3 axis by horizontal longitudinal and vertical. On the other hand the verities of mass from 50 to 100 kilograms and the several of weight distribution at horizontal and longitudinal are applied to the condition of testing for reasonable to the position of the center of mass. The result of research discovered to the performance of center of mass tester was activated following to test conditions. Furthermore the weight distribution at longitudinal was the highest effect to the horizontal center of mass. By the way the value of weight distribution at horizontal is more effects to the longitudinal center of mass. Moreover increasing of mass was impact to the vertical center of mass and it’s independent to the position of weight distribution.

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การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ โครงการวิจัยย่อยที่ 3 การแปรผันของสัดส่วนแรงเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับรถยนต์
การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ โครงการวิจัยย่อยที่ 3 การแปรผันของสัดส่วนแรงเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับรถยนต์

The aim of this research is to study the brake proportional affected to vehicle stability. Braking performance and vehicle stability testing are the main of research purposes. Otherwise learning research center and new researcher in automotive engineering are the minor research objectives. The results of research discovered to the braking performance depend on driver behavior. By the minimum deceleration was appeared on the non-proportion in front axle with braking ratio 0:100. In term of vehicle stabilities yaw and pitch moment are normally occur by the driving behavior. But the sideslip is an absolutely effect to vehicle handling. With the braking ratio 100:0 there is the highest risk for controlling a vehicle cause of the wheels were locked-up condition in the rear axle. Therefore the value of the sideslip was exceeded with the criteria. Furthermore these project researches were got the learning research center and the new researcher in automotive engineering field.

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Molecular weight polyethylene composites for high wear resistance under temperature changes and lubricant to apply for use in industrial machinery parts
Molecular weight polyethylene composites for high wear resistance under temperature changes and lubricant to apply for use in industrial machinery parts

The objective of this research is a study to determine optimum forming condition of semi-finished bulk UHMWPE by using ram extruder that obtain maximum yield strength and minimum wear rate for apply to use in area of medical and mechanical application. Experimental extrusion specified forming condition consists of the temperature of 140 150 and 160 ºC and pressure of 3 5 8 and 10 MPa with the temperature exposure time of 30 minutes. After known optimum forming condition of UHMWPE powder thus forming UHMWPE filled with different kind of filler to study and determine optimum weight fraction of various types of filler that affect onto wear resistance property of UHMWPE composites. Result extruded condition at the temperature of 1 5 0 ºC under pressure of 5 MPa with exposure time of 30 minutes is an optimum extruded condition due to specimen shown a maximum yield strength ultimate tensile strength and elongation of 20.43 ± 1.21 MPa 28.33 ± 1.53 MPa and 285.60 ± 6.41 % respectively and obtain minimum wear rate of 3.02  10-9 ± 5.27  10-10 mm3/Nm. Its mechanical properties and wear resistance property higher than imported bulk UHMWPE by 23.3 % and 4.75 times respectively due to the formation of cross-linking are occurred in polymer chain and also its degree of crystallinity is high equal to 61.52%. For bulk UHMWPE IR-spectrum shown a variation peak of carbonyl group (C=O) are occurred that that it indicated the oxidation reaction at the end of polymer chain and tis degree of crystallinity is equal to 53.31% which result to decrease strength of polymer. In the case of UHMWPE filled with filler optimum weight fractions of various types of filler are as follows. 1. The filling of 0.3 wt. % Al2O3 particle size 0.05 μm shown yield strength ultimate tensile strength and elongation of 23.17 ± 3.35 MPa 34.78 ± 2.80 MPa and 229.00 ± 6.09% respectively that its mechanical properties was increased by 18.55% (increasing of ultimate tensile strength). For the wear rate is equal to 2.09  10-9 ± 3.39  10-10 mm3/Nm or its wear resistance was increased by 1.44 times in compared with initial bulk UHMWPE. 2. The filling of 0.4 wt. % Al2O3 particle size 0.3 μm shown yield strength ultimate tensile strength and elongation of 21.93 ± 0.51 MPa 25.40 ± 0.69 MPa and 267.67 ± 22.03% respectively that its mechanical properties was increased by 11.54% (increasing of ultimate tensile strength). For the wear rate is equal to 2.32  10-9 ± 4.78  10-10 mm3/Nm or its wear resistance was increased by 1.30 times in compared with initial bulk UHMWPE. ฉ 3 . The filling of 0.4 wt. % Al2O3 particle size 1 μm shown yield strength ultimate tensile strength and elongation of 23.93 ± 1.89 MPa 26.77 ± 1.20 MPa and 296.54 ± 7.51% respectively that its mechanical properties was increased by 5.83% (increasing of ultimate tensile strength). For the wear rate is equal to 2.14  10-9 ± 3.16  10-10 mm3/Nm or its wear resistance was increased by 1.41 times in compared with initial bulk UHMWPE 4 . The filling of 4 wt. % Al2O3 particle size 5 μm shown yield strength ultimate tensile strength and elongation of 22.57 ± 2.01 MPa 26.31 ± 3.11 MPa and 136.66 ± 11.67% respectively that its mechanical properties was increased by 7.68% (increasing of ultimate tensile strength). For the wear rate is equal to 2.37  10-9 ± 5.71  10-10 mm3/Nm or its wear resistance was increased by 1.27 times in compared with initial bulk UHMWPE

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การศึกษาการใช้พลังงานในเครื่องอัดไฮดรอลิก
การศึกษาการใช้พลังงานในเครื่องอัดไฮดรอลิก

Recently Hydraulic Press has been generally used as a labor-saving device in several functions through industrial section. Previously most of the factory merely concern about using this powerful device and that caused so much electric energy wasted during the pending process on equipment transformation. Therefore our team initiated a conceptual study of energy consumption on using hydraulic press. The invention of hydraulic press for the study of electric energy requires hydraulic devices installation. This includes 3.7 kW 3 phases system induction motor and VSD hydraulic pump single shaft 2 sets set 1 low flow high pressure at flow rate 3.65 liters per minute and set 2 high flow low pressure at flow rate 6.79 liters per minute and total flow rate 10.44 liters per minute pressure relief valve and 2 ports 2 positions Bypass control valve and 4 ports 3 positions directional control valve double acting cylinder 100 mm diameter and 250 mm stroke and pressure gauge. The experiment on energy consumption using hydraulic press has been considered in 5 cases. Each case operated by different hydraulic devices in order to observe the differences of energy consumption. The result of experiment showed that case 1 had electric energy lost the most the rate of loss will increase as a percentage of the increase in pending. Case 2 to 4 with the lost of electric energy are similar. Case 5 is bringing the case 4 added VSD to adjust the speed of the electric motor is reduced to 435 rpm during the waiting period so this case had the lost of energy is minimal. After comparative experiment between case 1 and the other 4 cases during the pending process on equipment transformation at 20% - 200% it revealed that case 2 reduced electric energy wasted more than case 1 accounted for 17.07% - 30.46% while case 3 to 5 reduced electric energy wasted more than case 1 accounted for 16.06% - 29.52% 17.37% - 30.80% and 23.90% - 50.55% respectively

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การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ : เครื่องทดสอบจุดศูนย์กลางมวลสำหรับรถยนต์
การศึกษาจุดศูนย์กลางมวลและสัดส่วนการเบรกที่ส่งผลกระทบต่อเสถียรภาพการบังคับยานยนต์ : เครื่องทดสอบจุดศูนย์กลางมวลสำหรับรถยนต์

The aim of this research is to create the center of mass testing machine for vehicles with maximum mass 3000 kilograms. By the performance of this machine is able to determine the center of mass 3 axis by horizontal longitudinal and vertical. On the other hand the verities of mass from 50 to 250 kilograms and the several of weight distribution at horizontal and longitudinal are applied to the condition of testing for reasonable to the position of the center of gravity for vehicle. The result of research discovered to the performance of center of mass tester was activated following to test conditions. Furthermore the position of the horizontal of center of gravity depends on the weight distribution at horizontal axis and an increasing of mass under non-uniform along the longitudinal and horizontal axis. In term of the position of the longitudinal of center of gravity the weight distribution at longitudinal axis and an increasing of mass rate are points. Otherwise the weight distribution at longitudinal axis and an increasing of mass are effect to the position of the vertical of center of gravity.

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