Prof. Dr. Wiwiek Hendrowati ST MT when delivering his scientific oration regarding dynamic vibration damper engineering in boring bars for accuracy and precision in the manufacturing industry

ITS Campus, ITS News — In the manufacturing industry, accuracy and precision are important aspects. This need prompted the 180th Professor of the Institut Teknologi Sepuluh Nopember (ITS) Prof. Dr. Wiwiek Hendrowati ST MT to develop a dynamic vibration damper for boring bars to produce higher accuracy.

Wiwiek explained that in some conditions, the process of making an object requires a boring bar that is long and small in diameter. With this size, the boring bar tends to have a small level of stiffness, making it susceptible to bending and causing large vibrations. “This vibration will make the size of the hole you want to make inaccurate,” he explained.

Therefore, the first female professor from the ITS Department of Mechanical Engineering researched the Dynamic Vibration Absorber (DVA) which can absorb vibration energy in boring bars, to reduce vibrations. The way it works is by providing mass to a vibrating object. Between the object and this mass, a spring force can be applied which is responsible for dampening the existing vibrations.

In her research, this woman who was born in Madiun, on April 12, 1970, designed three different DVAs. The three DVAs are Ring Rubber Mass DVA, Spherical Rubber DVA, and Cone Rubber DVA. “These three DVA designs have their respective advantages and disadvantages,” said this doctoral graduate from the ITS Department of Mechanical Engineering.

Prof. Dr. Wiwiek Hendrowati ST MT explained the process of cutting boring bars with DVA

The first design, Ring Rubber Mass DVA consists of a mass and a rubber ring which is installed at the end of the boring bar. The advantage of this type is that it is easy to make and can be replaced more easily because it is installed on the outside. “However, this type of DVA is not able to reduce vibrations from the axial direction, only from the vertical and horizontal directions,” explained the lecturer who is also a Masters alumnus of the ITS Department of Mechanical Engineering.

The second design, Spherical Rubber DVA consists of a ball-shaped mass of rubber that is installed on the inside of the boring bar. This is the drawback of this type of DVA because the installation process is not as easy as the Rubber Mass DVA Ring. In addition, the perfect spherical shape required in this design is also difficult to create. However, the advantage of this type is its ability to reduce vibrations from all directions, namely vertical, horizontal, and axial.

The third design is the Cone Rubber DVA which is a more balanced design than the two previous designs. DVA with its conical mass shape can dampen vibrations from all directions like Spherical Rubber DVA and can still be easily dismantled. “However, Cone Rubber DVA’s dampening of vibrations from the axial axis is not as good as Spherical Rubber DVA,” added the mother of one child.

Certificate handover procession to ITS 180th Professor Prof Dr. Wiwiek Hendrowati ST MT (right) by the Chair of the ITS Professorial Council Prof Dr. Ir Imam Robandi MT

Another advantage of DVA, which was designed by women wearing the hijab, is that the price is more affordable than other DVAs. Therefore, Wiwiek hopes that the results of his research can be applied and able to reduce production costs in the manufacturing industry. “Apart from that, the ease of installation of this tool will also shorten production time,” he confirmed. (ITS Public Relations)

Reporter: Muhammad Fadhil Alfaruqi