Elemen Mesin I TKM4113 - Khairul Anam, ST., MSc.

TRIBOLOGI
TKM4094
PRINSIP DASAR TRIBOLOGI
Dosen Pengampu
Khairul Anam, ST., MSc.
Laboratorium Sentral Mesin, Gedung Mesin I, Lantai I
Jl. MT Haryono No. 167, Malang 65145
No. HP : +6281336327969
Email : k_anari27@yahoo.com
anamesin.lecture.ub.ac.id
Tujuan
Memberikan pemahaman tentang gesekan, aus
dan pelumasan serta pengaruhnya dalam
komponen mesin.
Pokok Bahasan
Prinsip dasar tribologi
Gesekan
Aus
Pelumasan
Tribologi pada kontak dengan kinematika rendah
Tribologi pada kontak dengan kinematika tinggi
Efisiensi pelumasan
Referensi
Introduction to Tribology_Bharat Bhushan
Tribology in Machine Design_TA Stolarski
Penilaian
Kehadiran  10%
Quiz  25%
Tugas  25%
UAS  40%
HP WAJIB DI SILENT ATAU DI NON-AKTIFKAN!
Tribologi
• Object
• Who
• Object
• Who
What
How
many/
• Result
• Analysis
How
much
Why
How
• When
• Where
Prinsip dasar tribologi
Tribologi dikenalkan pertama kali oleh Jost (1966)
Tribologi berasal dari bahasa yunani “TRIBOS” yang berarti
“BERGESEKAN”
Tribologi adalah cabang ilmu desain mesin (friction, wear
dan lubrication)
Prinsip dasar tribologi
Prinsip dasar tribologi
Elemen mesin yang harus mempertimbangkan tribologi
◦ Bantalan luncur
Prinsip dasar tribologi
◦ Bantalan gelinding
Piston
Prinsip dasar tribologi
◦ Cam
Friction Drive
Prinsip dasar tribologi
◦ Roda Gigi
Prinsip dasar tribologi
◦
◦
◦
◦
◦
◦
◦
Rem
Kopling
Mur-Baut
Seal
Semir
Menulis
Berjalan
Prinsip dasar tribologi
Koefisien Gesek dan Keausan
◦ Struktur (properti material)
◦ Kondisi saat mesin bekerja (beban, temperature, waktu, dan
lain-lain)
◦ Interaksi antar komponen
Prinsip dasar tribologi
Gaya Gesek (tanpa pelumasan)
◦ Gaya gesek selalu berlawanan arah dengan perpindahan
◦ F = fW
Dimana: F = Gaya Gesek
f = Koefisien Gesek
W = Gaya Normal
◦ Gaya gesek tidak tergantung pada luas kontak
The Nature of Surface
Chemical Reaction
The nature of Surface
Surface Texture
Macro  Micro
Kekasaran Permukaan
American National
Standards Institute
(ANSI)
International
Standardization
Organization (ISO)
The Future of
Tribology
PRACTICAL OBJECTIVES OF
TRIBOLOGY
FRICTION
TRIBOLOGY TRIANGLE
FRICTION
What is friction?



It’s a FORCE.
Occurs whenever two objects are IN CONTACT with each other.
It’s the resistance to movement. It SLOWS objects down.
24
FRICTION
Let’s use THE SAME FORCE to move the box on:
higher friction
wooden floor
lower friction
ice
In which case friction is higher? WHY?
Which one will slide further?
25
LUBRICATION
Why do we need it?
lower the friction
 prevent wear

↓ wear
↓ friction
remove heat and contamination
WEAR

What is wear?
It’s the removal of material
from a solid surface by the
action of another surface.
27
WEAR MECHANISMS
Adhesive
◦ Low contact pressures
◦ Augmented asperities
Abrasive
◦ High contact pressures
◦ Wear tracks
TYPES OF MOTION
There are two types of motion between two moving parts.
● Sliding motion
e.g :- Piston in IC engine
●Rolling motion
e.g :- Bearings, wheels of automobiles
TRIBOLOGY IN PISTON RINGS
AND CYLINDER LINER
Cylinder liner is fixed one
and piston will slide up
and down inside on it.
Friction exists between
these parts , it results in
wear.
It can be reduced by applying
lubricant.
RECENT DEVELOPMENTS IN
TRIBOLOGY
Soybean oil as future lubricant for IC engines.
Chemical Vapor Deposition (CVD)
Physical Vapor Deposition (PVD)
SOYBEAN OIL AS FUTURE
LUBRICANT FOR IC ENGINES
Soybean oil is a vegetable oil
extracted from soybean seeds.
It is easily available at low
price.
PROPERTIES OF SOYBEAN OIL :> It has a high viscosity index up to 223.
> Has comparatively high flash point 610°F.
> Has good fire point about 650°F.
> It has high pour point, it can be reduced by winterizing the
soybean oil.
ADVANTAGES OF SOYBEAN OIL
Soybean oil is biodegradable, in general it is less toxic.
It is a renewable oil, so it reduces dependency of foreign petroleum
products.
Ease of processing.
CHEMICAL VAPOUR DEPOSITION
CVD is used to grow a thin layer of advanced materials on
the surface of a substrate.
Application:Integrated circuits, electronic devices and sensors.
Catalysts
Micromachines, fine powder and ceramic powder protective coatings.
CHEMICAL VAPOUR DEPOSITION
Thin film is formed from gas phase
components.
CHEMICAL VAPOUR DEPOSITION
Two types of CVD:LPCVD (Low Pressure CVD ) :- Good uniformity, Used for poly-Si, oxide,
nitride.
PECVD (Plasma Enhanced CVD ) :- Low temperature process and high
deposition rate. Used for oxide, nitride, etc.
CHEMICAL VAPOUR DEPOSITION
Pressure sensor
Resistance-heated furnace
Quartz tube
Trap
To exhaust
Si Wafers
Pump
Gas control
system
Source
gases
LPCVD Systems
PHYSICAL VAPOUR DEPOSITION
PVD is a fundamentally a vaporization coating technique,
involving transfer of material on an atomic level.
It is an alternative process to electroplating.
The process is similar to chemical vapor deposition (CVD) except
for the raw materials.
i.e. the material that is to be deposited starts in solid form,
whereas in CVD the precursors are introduced to the reaction
chamber in gaseous state.
APPLICATIONS OF PVD
PVD coatings are used to improve Hardness, Wear Resistance, Oxidation
Resistance.
Thus, such coatings used in variety of applications
such as :Aerospace
Automotive
Surgical/medical
Dies and moulds for all manner of material processing
Cutting tools
Fire arms
ECONOMIC ASPECTS OF
TRIBOLOGY
The LUBRICANT REPORT estimated an amount
exceeding 500 million pounds can be saved in the
civilian sector of UK by research in tribology.
The estimated 11 % total savings in annual US energy
consumption is equivalent to some 16 billion US dollars
by an expenditure in research and development o f an
estimated twenty-four million dollars.
Analysis of the failure of boiler tubes indicate that
about one-third of all occurrences were due to erosion.
In UK, the application of tribological principles can
effect national energy savings. These are estimated at
468 to 700 million pounds per annum.
IMPACT OF TRIBOLOGY
Since the publication of the Lubrication Report there has been an
increasing awareness throughout industry of the subject of
tribology.
In the UK the National Centre for Tribology and Industrial Units of
Tribology have been set up to provide advice t o industry on the
utilisation of existing knowledge.
Tribology is now recognized universally and President Carter of
U.S.A. declared it to be a generic technology underlying many
industrial sections and the prospectus for an Industrial Tribology
Institute at Rensselaer Technology Center has been presented.