TRIBOLOGITKM4094PRINSIP DASAR TRIBOLOGI

Dosen PengampuKhairul 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

TujuanMemberikan pemahaman tentang gesekan, ausdan pelumasan serta pengaruhnya dalamkomponen mesin.

Pokok BahasanPrinsip dasar tribologi

Gesekan

Aus

Pelumasan

Tribologi pada kontak dengan kinematika rendah

Tribologi pada kontak dengan kinematika tinggi

Efisiensi pelumasan

ReferensiIntroduction to Tribology_Bharat Bhushan

Tribology in Machine Design_TA Stolarski

PenilaianKehadiran 10%

Quiz 25%

Tugas 25%

UAS 40%

HP WAJIB DI SILENT ATAU DI NON-AKTIFKAN!

Tribologi

• When

• Where

• Result

• Analysis

• Object

• Who

• Object

• Who

What Why

How

How many/

How much

Prinsip dasar tribologiTribologi dikenalkan pertama kali oleh Jost (1966)

Tribologi berasal dari bahasa yunani “TRIBOS” yang berarti“BERGESEKAN”

Tribologi adalah cabang ilmu desain mesin (friction, weardan lubrication)

Prinsip dasar tribologi

Prinsip dasar tribologiElemen 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 tribologiKoefisien Gesek dan Keausan◦ Struktur (properti material)

◦ Kondisi saat mesin bekerja (beban, temperature, waktu, danlain-lain)

◦ Interaksi antar komponen

Prinsip dasar tribologiGaya 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 ReactionThe nature of Surface

Surface TextureMacro Micro

Kekasaran Permukaan

American National Standards Institute (ANSI)

International Standardization Organization (ISO)

The Future of Tribology

PRACTICAL OBJECTIVES OF TRIBOLOGY

FRICTION

TRIBOLOGY TRIANGLE

FRICTIONWhat is friction?

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It’s a FORCE.

Occurs whenever two objects are IN CONTACT with each other.

It’s the resistance to movement. It SLOWS objects down.

higher friction

lower friction

25

FRICTIONLet’s use THE SAME FORCE to move the box on:

wooden floor

ice

Which one will slide further?In which case friction is higher? WHY?

LUBRICATIONWhy do we need it?

↓ friction

↓ wear

remove heat and contamination

lower the friction

prevent wear

WEAR

What is wear?

It’s the removal of material from a solid surface by the action of another surface.

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WEAR MECHANISMSAdhesive

◦ Low contact pressures

◦ Augmented asperities

Abrasive ◦ High contact pressures

◦ Wear tracks

TYPES OF MOTIONThere 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 TRIBOLOGYSoybean oil as future lubricant for IC engines.

Chemical Vapor Deposition (CVD)

Physical Vapor Deposition (PVD)

SOYBEAN OIL AS FUTURE LUBRICANT FOR IC ENGINESSoybean 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 OILSoybean 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 DEPOSITIONCVD 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 DEPOSITIONTwo 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

Si Wafers

Quartz tube

Resistance-heated furnacePressure sensor

Gas control

Source gases

Pump

Trap exhaust To

system

LPCVD Systems

PHYSICAL VAPOUR DEPOSITIONPVD 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 PVDPVD 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 TRIBOLOGYThe 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 dollarsby 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.