International Islamic University Malaysia Engineering industrial training (Eit 4004) OMNI OIL TECHNOLOGIES (ASIA) SDN BHD Name: Mohd Affizul Ariff Bin Salim Matric No: (0710841) Discipline: Bachelor of Mechanical Automotive Engineering Department: Mechanical Visiting Lecturer: Dr Mirghani Training Period: 12 th April 2010 – 2 nd July 2010 Year: 2010
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International Islamic University
Malaysia
Engineering industrial training
(Eit 4004)
OMNI OIL TECHNOLOGIES (ASIA)
SDN BHD
Name: Mohd Affizul Ariff Bin Salim
Matric No: (0710841)
Discipline: Bachelor of Mechanical Automotive Engineering
Department: Mechanical
Visiting Lecturer: Dr Mirghani
Training Period: 12th April 2010 – 2
nd July 2010
Year: 2010
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
COMPANY VERIFICATION STATEMENT
I hereby declared that, MOHD AFFIZUL ARIFF BIN SALIM (Matric No: 0710841) student of
DEPARTMENT OF MECHANICAL ENGINEERING, International Islamic University Malaysia (IIUM)
has successfully completed his Engineering Industrial Training from 12th April 2010 till 2nd July
2010 at OMNI OIL TECHNOLOGIES (ASIA) SDN BHD under Quality Control Department and
Engineering Department.
This report is prepared by above-mentioned student as a partial fulfillment of this training. All
information given in this report is true and does not contain any confidential information or
classified data that might in a way or another abuse the company’s policies
Approved by,
Mr. Zulkiflee Samsi
Manufacturing Engineer act as Plant Manager
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
(i)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
ACKNOWLEDGEMENT
In the name of ALLAH, the Most Gracious and Most Merciful, I thank ALLAH SWT for
bestowing me with health, knowledge, patience and determination to complete the
Engineering Industrial Training at OMNI OIL TECHNOLOGIES (ASIA) SDN BHD.
Therefore, I acknowledge with great gratitude to Engineering Department and Quality
Control department of OMNI OIL TECHNOLOGIES (ASIA) SDN BHD, which supervised by Mr.
Zulkiflee Samsi and Mr. Hanafi Mamat for willingness to train me, giving advices, sharing
experiences, and giving encouragement to me. Biggest appreciation to Quality Control
Inspector, Mr. Md Shah and Mr. Yazid Sabarani for continuously supporting and providing me
with all great lessons and valuable experiences during the time I was in the company.
Acknowledgement also to Mr. Hisham Serry act as Production Engineer for his kindness
and for treating me nicely and equally like other permanent staffs in OMNI OIL TECHNOLOGIES
(ASIA) SDN BHD. Millions appreciation goes to all staffs, engineers, senior technicians and
technicians for sharing their knowledge and for welcoming me to be part of OMNI OIL
TENOLOGIES member.
Also I would like to express my greatest appreciation to my visiting lecturer Dr MIrghani
for his consultation and advice to complete my final presentation and report and also for the
assessment throughout this engineering industrial training. Special thank goes to my
colleagues, Bro Khairul Muhaimin who always helped and support to solve all engineering work
throughout the training process. Finally, my highest appreciation goes to my beloved parents
for the moral support and encouragement to fulfill successfully this engineering industrial
training.
(ii)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
SUMMARY
This Engineering Industrial Training report is prepared for the purpose of fulfilling the
final requirement upon completion of the EIT program which had been underwent during
semester 3, 2009/2010 session. This report contains all the relevant information and
description regarding the training program which has been successfully completed at OMNI OIL
TECHNOLOGIES (ASIA) SDN BHD. It also discusses the activities and contribution towards the
company throughout the training program period.
There were no specific projects assigned to the students, instead the students were
placed to various section within the company such as Quality Control Department section
Assembly Department section and Engineering Department section. Any tasks given are
subjected to the supervision of personnel of each section.
This Engineering Industrial Training is beneficial for the students since it will enhance
their knowledge regarding engineering work throughout the practical training. During the
training, it helps the student to build up their level of confidence as well as how to respect
other peoples such as technician or engineer. It is a platform for the students to be more
adaptable to real working environment and to develop as well as to enhance their interpersonal
skills. More over it can develop the skills, ability, and competency of the students throughout
this industrial training.
(iii)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
BACKGROUND OF OMNI OIL TECHNOLOGIES
Omni Oil Technologies is the first leading edge integrated technology development and
manufacturing center that was set up in the Middle East early 2004 for drilling tools for the Oil
and Gas industry. It is conveniently based in Dubai prominent Free Zone, Jebel Ali, United Arab
Emirates. Omni oil is capable of developing, modifying and producing customized tools to deal
with even the most extreme down holes challenges.
Omni currently operates throughout the Middle East and North Africa in major oilfield
centers such as Saudi Arabia, U.A.E., Oman, Kuwait, Egypt and Sudan. A larger manufacturing
facility for OMNI is currently under construction in Jebel Ali Free Zone in order to face up to the
increased demand for OMNI products. In addition, another manufacturing center is under
establishment in Malaysia to cover the Asia Pacific market needs.
“We are committed to excellence in standards and quality control and providing unmatched
local support,” says Mr. Mohammad Makhlouf, the President/CEO of the company.
All OMNI products adhere to API standards and are assured through a quality
management system in accordance with ISO-9001 2000. All OMNI tools are designed and
analyzed using leading edge technologies in design and stress analysis using Finite Element
Analysis (FEA) computer simulation packages. The manufacturing facility is equipped with
Computer Numerically Controlled (CNC) production lines, delivering precisions manufacturing
to the highest worldwide standards.
(1)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
MISSION AND VISION OF OMNI OIL TECHNOLOGIES
To create a product development and manufacturing organization that serves the oil
and gas industry in the Middle East and grows profitably and independently into the global markets in an environmentally friendly manner while maximizing value to its shareholders and surrounding community and become the preferred organization of choice to its employees and customers
To provide a training and development platform for emerging regional human capital and place the region on the front end of technical innovation and development in the global oil and gas industry
To become the leading global technology development and manufacturing organization in the oil and gas industry originating from the Middle East
(2)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
PRODUCT OF OMNI OIL TECHNOLOGIES
OMNI Oil Technologies is an approved supplier of Drilling Enhancement Tools for the major national oil companies through the Middle East. OMNI Drilling Enhancement Tools are deployed in many locations and in a variety of different formation lithologies around the region. Furthermore, these tools have shown outstanding performance in total operating hours. OMNI Oil Technologies Drilling Enhancement Tools are compatible with any BHA configuration thereby improving the overall drilling performance in well bores of all sizes. OMNI's current products are branded as the “Bassal” generation of products after their chief designer, Mr. Adel Bassal.
OMNI products are classified into three groups:
(3)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
OBJECTIVES OF ENGINEERING INDUSTRIAL TRAINING
To provide student with industrial working environment
To provide students with job experience
To assist students to acquire knowledge related to Oil and Gas industry, and company
Administration Systems.
To assist student to gain informal learning process regarding engineering studies
(4)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
ROLES DURING ENGINEERING INDUSTRIAL TRAINING
Join Quality Control Department on 12th April 2010
1st week – to be familiar with all measuring tools and equipment in QC department such as Holtest, Digital Calliper, Vernier Calliper, Rotary work plug, Rotary work ring, Block Gauge, Dial Gauge and others.
2nd week – to be able to measure threading for different bodies such as flexi joint 6.5 inches and flexi joint 8.00 inches also for roller reamer 17.5 inches. There different types of threading which are 4 ½ Internal Flush Threading, 6 5/8 Regular Threading, 7 5/8 Regular Threading. The threading measurement done by using thread height gauge, rotary work plug, rotary work ring, bore gauge, outer micrometer, thread profile 4 1/2 IF, 6 5/8 REG, 7 5/8 REG, API Gauge, Lead gauge and others. Also measure the diameter of flexi joint 8.00 inches and 6.75 inches.
3rd week – Do the quality file for flexi Joint 8.00 inches and 6.75 inches. In this quality file, it includes inspection standard, inspection test plan (bubble drawing), Inspection check sheet, Drawing A3 size and also the NCR report. Before the inspection check sheet is done, must refer to the drawing to check the tolerance for each parameter and also check the bubble drawing parameter
4th week - Check the flexi joint again with brother Shah to confirm the length dimension by using the Big Milling Centre 3 (BMC 3) machine. This due to the accuracy of measurement by using the BMC 3 is higher rather than by using measuring tape. The measurement by using BMC 3 machine is up to 3 decimal points rather than using tape measure which is up to only 2 decimal points. With BMC 3 machine also we can check the straightness and roundness of the flexi joint.
5th week – Check the dimension of RR Pin since it cannot be assembles with the RR cutter. Do the measurement for the diameter of the RR Pin and all the dimension are within the tolerance. Then, carry out the straightness check for RR Pin at the Granite table by using the Filler Gauge. Then only we can detect the straightness problem which is around 50 micron.
(5)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
6th week – Do the length measurement for driver sub 10 inches and driver sub tapered 7.5 inches with brother shah. Also check the straightness and roundness of driver sub 10 inches and driver sub tapered 7.5. Also check the surface roughness at the machining site for mandrel upper and mandrel lower. Regarding the measurement of radius which is difficult to be measured, brother shah and me do the testing by using the silicon putty and put the silicon putty at the designated area so that the radius can be measured by using CMM machine.
7th week – Do the inspection check sheet of mandrel upper and mandrel lower, also the inspection standard for mandrel upper and mandrel lower, with the inspection test plan (bubble drawing) and the original drawing for mandrel upper and mandrel lower. Do the inspection check sheet of driver sub, also the inspection standard, the inspection test plan (bubble drawing) and the original drawing for mandrel upper and mandrel lower. Revise the flexi joint check sheet, inspection test plan (bubble drawing), inspection standard and the original drawing A3 size. The entire documents are in soft copy form.
8th week – Do the checking and inspection for the quality control’s equipment such as outer micrometer, rotary work plug and rotary work ring. This due to the existence of corrosion at the surface of the equipment and need to be removed from the surface. Also do the checking for all equipment’s serial numbers and do the marking of the serial number at all equipments.
9th week – Do the inspection for upper block and lower block with bro Yazid and identify the incomplete inspection for upper block and lower block. There are 2 batches which consist of 24 pieces. Also do the packing for cutter, upper block, and lower block and pin to be sent for nitriding process.
10th week – Join Assembly Process Department on 8th June 2010. Do the assembly process between tungsten carbide insert and cutter. Do the hardness test for the heat treated jig with Bro Halim. Do the assembly process for cartridge, which consist of upper block, lower block and cutter.
(6)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
11th week – Do assembly process for cutter and pin with piston, spring and oil ring. Then do the assembly for cartridge, which consist of upper block, lower block and cutter. Do inspection for raw material which given from the supplier. Need to confirm the dimension such as diameter and length.
12th week – Visit to Umetoko Company in Kota Kemuning Shah Alam to see the nitriding process. Preparation of final presentation slide and also final report on Engineering Industrial Training
(7)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
MANUFACTURING PROCESS
The word manufacturing is derived from the Latin manu factus, meaning made by hand.
The word manufacture first appeared in 1567 and the word “manufacturing” appeared in 1683.
The word product and production first appeared sometime during the 15th century. The word
“manufacturing” and “production” often are used interchangeably.
For any manufacturing company such as OMNI OIL TECHNOLOGIES (ASIA) SDN BHD,
manufacturing is generally a complex activity involving a wide variety of resources such as:
- Product design
- Machinery and tooling
- Process planning
- Materials
- Purchasing
- Manufacturing
- Production control
- Support services
- Marketing
- Sales
- Shipping
- Customer service
(8)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
MANUFACTURING PROCESS AT OMNI OIL TECHNOLOGIES
(9)
Raw material
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
(10)
Tools (Steady rest)
Equipment
(CNC BIG MILLING
CENTER)
Equipment
(CNC BIG TURNING
CENTER)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
(11)
Labor / Workforce
Waste (chips)
Finished Product Rejected Product
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
It is essential that manufacturing activities be responsive to several demands and trends:
1. Product must fully meet design requirement, product specification and standard
2. A product must be manufactured by the most economical and environmentally friendly
methods
3. Quality must be build into the product at each stage, from design to assembly rather
than relying on quality testing after the product is manufactured
4. In the highly competitive environment of today, production methods must be
sufficiently flexible to respond changing market demands, types of products, production
rates, production quantities, and provide on time delivery to customer.
5. Continuous developments in materials, production methods, and computer integration
of both technological and managerial activities in a manufacturing organization must be
evaluated constantly with a view to their appropriate, timely, and economical
implementation
6. Manufacturing activities must be reviewed as a large system, all parts of which are
interrelated to varying degrees. Such systems can now be modeled in order to study the
effect of factors such as changes in market demands, product design, materials, and
production methods on product quality and cost.
7. The manufacturer must work with customer for timely feedback for continuous product
improvement.
8. A manufacturing organization constantly must strive for higher levels of productivity,
defined as the optimum use of all its resources such as materials, machines, energy,
capital, labor, and technology; output per employee per hour in phase must be
maximized.
(12)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
SELECTION OF MATERIAL
(13)
Selection of material
Properties of material Cost and availability Appearance, service life and
recycling
The appearance of materials,
after they have been
manufactured into products,
influences their appeal to the
consumer. Color, feel and surface
texture are characteristics that we
all consider when marking a
decision about purchasing a
particular product.
The economic aspects of material
selection are also important as
technological consideration of the
properties and characteristic of
material. If raw materials or
manufactured component are not
available in desired shapes,
dimension, and quantities, hence
additional processing will be
required and this situation will
lead to increase in the production
cost.
The first consideration is the
mechanical properties of the
material such as strength,
toughness, ductility, hardness,
elasticity, fatigue and creep.
The next consideration is the
physical properties of the material
such as density, specific heat,
thermal expansion, thermal
conductivity, melting points, and
electrical and magnetic properties.
A combination of mechanical and
physical properties is the strength
to weight and stiffness to weight
ratios of the material, particularly
important aerospace, automotive
and petroleum industry.
Chemical properties play an
important part such as oxidation,
corrosion, general degradation,
toxicity and flammability.
Manufacturing properties of
material whether it can be cast,
formed, machined, joined, and
heat treated, with relative ease.
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
BEHAVIOUR AND MANUFACTURING
PROPERTIES OF MATERIAL
(14)
-Heat Treatment
-Precipitation Hardening
-Annealing
-Tempering
-Surface Treatment
-Alloying
-Reinforcement
-Composites
-Laminations
-Fillers
-Density
-Melting Point
-Specific Heat
-Thermal Conductivity
-Thermal Expansion
-Electrical Conductivity
-Magnetic Property
-Oxidation
-Corrosion
-Atomic bond:
Metallic, covalent and ionic
-Crystalline
-Amorphous
-Partly Crystalline
-Polymer Chains
-Strength
-Ductility
-Elasticity
-Hardness
-Fatigue
-Creep
-Toughness
-Fracture
Structure of
materials
Mechanical properties Physical and Chemical
properties
Property modification
Behavior and manufacturing
properties of materials
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
HEAT TREATMENT PROCESS
The properties and behavior of metal and alloy during manufacturing and performance
during their service life depend on their composition, structure, processing history and as well
as heat treatment process to which they have been subjected. The important properties such
as strength, hardness, ductility, toughness and resistance to wear are influenced greatly by
alloying elements and heat treatment process. By doing heat treatment processes it can
modifies the microstructures and change the mechanical properties such as formability,
machinability, hardness, toughness and strength.
As for OMNI OIL TECHNOLOGIES (ASIA), the implementation of heat treatment process
is done for the purpose of hardening the jigs which is used for machining process and quality
inspection process.
As shown in the picture, it is during the heating process of the jig. The required
temperature is about 800 °C and the increment of the temperature is measured by using the
temperature sensor.
(15)
JIG
COOLANT
FLAME
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
After about 3 hours heating the jig, thus the temperature reaches 800 °C. So after that we
need to immediately immerse the jig inside the coolant. This is rapid cooling process since we
desired the properties of the jig to be very hard as compared to initial properties of the jig. This
process is known as quenching process.
There are 7 different cooling processes which are:
Quenching
This is the process in which the heated material is being rapidly cooled by using water, oil,
coolant or other cooling liquid as a medium of cooling. By doing quenching process, it has
great rate of cooling and instantaneously the heated material will be in the normal
temperature again. The property of the material differ from the untreated material such as
increase in hardness value, become brittle, increase in strength and toughness value and
not uniform grain structure (Formation of martensite microstructure)
Normalizing
This is the process in which the heated material is cooled down in the open air in the room
temperature. By doing normalizing process, it has better rate of cooling as compared to
annealing process and the will be in the normal temperature again for about 4 to 5 hours.
The property of the material will be different than the untreated material such as slightly
increase in hardness value, increase in ductility, and slightly increase in strength and
toughness value, and also slightly uniform grain structure (Formation of partly martensite
and partly pearlite microstructure). The normalizing process also is done to refine the grain
boundaries.
(16)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
Annealing
This is the process in which the heated material is cooled down very slowly inside the
heating furnace. By doing annealing process, it has the lowest cooling rate as compared to
the normalizing process and quenching process. The material will be in the normal
temperature again for about 1 day after the heating process is done. The property of the
material will differ than the untreated material in term of the hardness since annealing
process will have the lowest hardness value than quenching and normalizing process. The
other property which differs is the ductility in which the annealed material will be very
ductile. Furthermore, the annealed material will have less strength and toughness value.
The annealed material also will have very fine and uniform grain structure. (Formation of
pearlite microstructure)
Tampering
In tempering process the material is heated to a specific temperature (depend on the
composition of the material) and it is cooled down under prescribed rate of cooling.
Tempering process is used to reduce brittleness, increase ductility and toughness and
reduce the residual stress.
Austempering
In austempering process, the heated material is quenched rapidly from the austenitizing
temperature to avoid formation of ferrite and pearlite microstructure. It is then held at a
certain temperature until isothermal transformation from austenite to bainite
microstructure is complete. It is then cooled down to room temperature. Austempering
process is used to substitute the conventional quenching and tempering in which to reduce
the tendency toward cracking, and distortion during quenching, to improve ductility and
toughness while maintaining hardness value.
Martempering
In martempering process, the heated material is first quenched from austenitizing
temperature in a hot fluid medium such as hot oil or molten salt. Then it is held at that
temperature until the temperature is uniform throughout the material, and being cooled at
moderate rate such as in air. Martempered material has fewer tendencies to crack, distort,
or develop residual stress during heat treatment process.
(17)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
Ausforming
In ausforming process the material is formed into desired shapes within controlled ranges
of temperature and time to avoid formation of nonmartensitic transformation product. The
part is then cooled at various rates to obtain the desired microstructures. Ausformed
material has superior mechanical properties.
To clearly see the different microstructures such as pearlite, bainite, ferrite and
martensite, it can be visualize through microscope and electron microscope.
(18)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
SURFACE TREATMENTS AND COATINGS
After the part is manufactured, some of its surfaces may have to be processed further in
order to ensure certain properties and characteristics. It may be necessary to perform surface
treatments in order to:
Improve resistance to wear, erosion, and indentation
Control friction (sliding surfaces of tools, dies, bearings, and machine ways)
Reduce adhesion (electrical contact)
Improve lubrication
Improve resistance to corrosion and oxidation
Improve fatigue resistance
Rebuild surfaces
Modify surface textures
Impart decorative features
(19)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
(1) Mechanical Surface Treatment Shot Peening Process
In shot peening the workpiece surface is impacted repeatedly with a large number of
cast steel, glass, or ceramic shot (small ball), which make overlapping indentation on the
surface. This action causes plastic surface deformation at depths up to 1.25 mm using shot sizes
that ranges from 0.125 to 5 mm in diameter. Because of the plastic deformation is not uniform,
throughout the part’s thickness, shot peening causes compressive residual stresses on the
surface, thus improving the fatigue life of the component by delaying fatigue crack initiation.
Unless the process parameters are controlled properly, the plastic deformation of the surface
can be so severe that it can damage the surface. However it should be noted that (if these parts
are subjected to high temperature) the residual stress will begin to relax (thermal relaxation)
and their beneficial effects will be diminished greatly.
(20)
Shot peening surface
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
(2) Case Hardening Nitriding Process
Methods of case hardening are such as carburizing, carbonitriding, cyaniding, nitriding,
flame hardening, and induction hardening. Case hardening as well as some of other surface
treatment processes induces residual stresses on the surface of the material. The formation of
martensite microstructure during case hardening causes compressive residual stresses on
surface. Such stresses are desirable since it will improve the fatigue life of the component by
delaying the initiation of fatigue crack.
As the engineering industrial training (EIT) conducted at OMNI OIL TECHNOOGIES (ASIA)
SDN BHD, the case hardening process also already implemented to improve the fatigue life of
the material such as roller reamer. The case hardening process that being used is nitriding.
Nitriding is a heat treating process that alloys nitrogen into the surface of a metal to
create a case hardened surface. It is predominantly used on steel but also titanium, aluminum
and molybdenum. The processes are named after the medium used to donate nitrogen. The
three main methods used are:
Gas nitriding
Salt bath nitriding
Plasma nitriding
(21)
After nitriding process
(surface are slightly darker)
Before nitriding process
(surface are shining)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
Gas Nitriding
In gas nitriding the donor is nitrogen rich gas usually ammonia (NH3), which is why it
is sometimes known as ammonia nitriding. When ammonia comes into contact with the
heated work piece it disassociates into nitrogen and hydrogen. The nitrogen then
diffuses from the surface into the core of the material.
The advantages of gas nitriding are:
All round nitriding effect
Large batch sizes possible
With modern computer control of the atmosphere the nitriding result can be
tightly controlled
Relative cheap equipment cost
The disadvantages of gas nitriding are:
Reaction kinetics heavily influenced by surface condition
Surface activation is sometimes required to successfully treat with a high
chromium content
Ammonia as nitriding medium (toxicity which is harmful when inhaled in large
quantities and when there is presence of oxygen there is risk of explosion)
(22)
MOHD AFFIZUL ARIFF BIN SALIM 0710841
OMNI OIL TECHNOLOGIES (ASIA) SDN BHD
Salt Bath Nitriding
In salt bath nitriding the nitrogen donating medium is a nitrogen containing salt such as
cyanide salt. The salt used also donates carbon to the workpiece surface making salt bath a
nitrocarburizing process. The temperature used is typical of all nitrocarburizing processes 550-
590 °C
The advantages of salt bath nitriding are:
Quick processing time
Simple operation
The disadvantages of gas nitriding are:
The salt used are highly toxic
Only one process possible with a particular salt type
Plasma Nitriding
Plasma nitriding also known as ion nitriding, plasma ion nitriding, or glow discharge is an
industrial surface hardening treatment for metallic materials. There is hot plasma, typified by
plasma jets used for metal cutting, welding, cladding or spraying. There is also cold plasma
usually generated inside vacuum chambers at low pressure regimes. Here high temperature
characteristics of the ionized gases are not used, but the electronic properties become useful.
Thus an ionized gas like nitrogen in such a low pressure regime becomes much more reactive.
The advantages of plasma nitriding are:
Close control of the nitride microstructure
Allowing nitriding with or without compound layer formation
Performance of metal parts get enhance
Working lifespan gets boosted
Strain limit and fatigue strength are being treated