จำนวน Repository ( 2 )
การเพิ่มประสิทธิภาพการผลิตอิฐช่องลมลวดลายอาหรับ การณีศึกษา : มุสลิมโมเดิร์น์ จังหวัดปัตตานี
The objective of this study is to improve the efficiency in manufacturing process of Arabian-style ventilation bricks with a new production method that uses a machine. The study focuses on all steps of productions in order to increase productivity. After the experiment the study shows that the improvement of ventilation brick manufacturing includes the increase in production volume from 20 pieces per day to 50 pieces per day representing an increase of 76.19 percent; and the decrease in production cycle time originally from 1401 minutes per piece to 97 minutes per piece representing a decrease of 93.07 percent respectively.
อิทธิพลของความเร็วรอบที่ส่งผลต่อสมบัติทางกลของการเชื่อมอะลูมิเนียมต่างชนิด ระหว่าง SSM7075 กับ SSM356 ด้วยการเชื่อมเสียดทาน
The objective of this research is to study how rotation speeds affect mechanical properties with friction welding between semi-solid metal 7075 aluminum alloys and semi-solid metal 356 aluminum alloys. The factor of interest is rotation speeds with different conditions at 800 1000 1200 1400 and 1600 rpm respectively. 1.8 millimeter for burn of length 30 seconds for welding time and clockwise rotation are set as a control constant condition for the entire experiment. After friction welding we found that different rotation speeds significantly affected mechanical properties of these alloys. At rotation speed 1400 rpm the maximum tensile strength is 122.24 MPa and the maximum hardness in welded zone is 140.5 HV. The microstructure size is 2.250 µm long and 2.144 µm wide. Its size in welded zone is practically small because of friction force. Moreover this friction force causes the mixture of MgZn2 and Mg2Si in welded zone.