PENGARUH PERLAKUAN PANAS PADA PEMBENTUKAN PELAT BERALUR PANEL KENDARAAN TERHADAP PENINGKATAN FREKUENSI ALAMIAH DIUKUR PADA KONDISI BATAS JEPIT-JEPIT
ABSTRACT: Vehicle
Comfortability in a minibus is highly influenced by the noise level and the
mechanical vibration on the cabin. Sound and vibration can come from the engine
excitation, the pressure difference in both inside and outside of the cabin,
the road roughness and the primary vehicle’s structure. The ground, wall and
floor of the cabin in a vehicle are the most influenced parts in the role of
transmitting sounds and vibrations. These can be reduced by means of increasing
the cabin’s stiffness. Sheet metal is mainly used as the cabin’s material. Its
stiffness can also be increased by means of thickening, grooving and embossing
the plate. The aims of this experimental work are to increase both the natural
frequency and the stiffness of the plate by means of forming and grooving in
the cabin’s plate. The material used in this paper is mild steel plate 0,8 mm
from galvanized steel that is generally used in manufacturing of the minibus
vehicle (ASTM A 29 coated with zinc an aluminum). The research method is
derived as follows: determining the panel dimension, calculating the number of
the groove, designing both the heating temperature and the cooling media,
grooving process, measuring and analyzing the natural frequency and the
stiffness. The length and the width of the panel dimension are determined by
550 mm and 550 mm, respectively. Trapezium cross-section is used as groove’s
design. The results show that the natural frequency and the stiffness are linearly
influenced by residual stress. The highest frequency, reached at 258,06 Hz, is
to be found at 10 groove with temperature of 700 C and followed by
water cooling. In addition, this frequency is increased nine times
compared with plain panel without groove in which it has 27,55 Hz.
Penulis: Sukanto, Erwanto
Kode Jurnal: jptmesindd160337