It is made of stainless steel

Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
MEM30007A Select Common Engineering Materials
Material and Processing - Product Study
Mitsubishi Turbocharger TC05
Part 1:
List all the components. (There should be at least 25 parts). Give every part a number, and
also make up names for each component - an interesting task in itself! Designers and
engineers often get the job of making up a name for something, and it's not always easy. Try
to make each name unique.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Part 2:
Identify/estimate/assume the material that each component is made of.
State how you made your identification.
List some alternative materials that could have been used instead.
Identify/estimate/assume and describe the processes that were probably used to produce each
component listed in Part 2 - from the semi-finished materials. (i.e. Don't describe the process
of making a steel spring from iron ore, but from steel wire)
Identify post-treatment processes such as heat treatment, coating, plating, painting etc for any
relevant components
1. Rivet screw
Rivets, screws and nuts manufactured from molybdenum, tungsten, tantalum and niobium as well as
a wide range of alloys.
A solid rivet has a manufactured head on one end and a solid shank on the other end. The
shank of the rivet can be produced with a straight cut-off or a chamfered cut-off end. A die
point can be manufactured into the shank end to aid alignment during assembly. Common
head styles are oval, truss, round, button, universal, pan, countersunk and flat.
Solid rivets are the strongest rivets used in fastened joints. Secondary heat treatment (anneal)
to the rivet can make the rivet more ductile prior to clinching in certain applications. Rivets
can be hardened for some applications to improve strength and durability. Rivet plating and
coating options are selected dependent on the application. Many solid rivets are ordered with
a plain finish as they are painted after assembly.
Common materials used for solid rivets:
Stainless steel
To fasten the rivet, the end of the shank is impacted, pressed or spun after the rivet has been
inserted into a work-piece. A solid head is formed (upset) to create the clinched head of the
rivet. When impact or press clinched, the force required to form the clinched head of the rivet
swells the entire shank of the rivet to completely fill the work-piece hole. Swelling of the
shank occurs most by the clinched head end of the rivet. Spun/orbital/radial rivet clinches
require less tonnage to form than impact or pressed rivets; therefore, do not have the same
shank swelling capability. Pre-punched or drilled work-piece holes are required for use on
most solid rivet applications.
2. Name plate
It is made of Aluminium.
Its non magnetic.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Brass - you do not have to remove to immerse in chemical cleaning solution such as caustic,
Computer generated bar-coded stick on label
A nameplate identifies and displays a person or product's name. Name plates are usually
shaped as rectangles but are also seen in other shapes, sometimes taking on the shape of
someone’s name. The primary use of name plates is for informative (as in an office
environment, where name plates are mounted on doors or walls in order to identify
employees) and commercial purposes (as in a retail environment, where name plates are
mounted on products to identify the brand). Whereas name tags tend to be worn on uniforms
or clothing, name plates tend to be mounted onto an object (e.g. cars, amplification devices)
or physical space (e.g. doors, walls, or desktops). Nameplates are also distinct from name
plaque. Plaques are items of larger dimensions that are designed to communicate more
information than a name and title
Cut out of Aluminium plate, serial, part and model number paint printed, or number letter
punched, holes drilled for the rivet screws
3. Compressor cover
It is made of Aluminium.
It is non magnetic.
Cast iron for high pressure applications.
Compressor housings are also made in cast aluminium. Various grades are used to suit the
application. Both gravity die and sand casting techniques are used. Profile machining to
match the developed compressor blade shape is important to achieve performance
Cast and machined, held in lathe in a 4 jaw chuck set up and air inlet machined to required
size to suit hose. Removed and held in lathe in a 4 jaw chuck held at air inlet and reset on to
machine bearing housing mating diameter and faces and regrooved to suit snap ring
4.Cartridge assembly (please refer bill of materials or individual components breakdown list)
5. Lock Nut
It made of spring steel.
It is springy.
Nylock lock nuts.
6. Wheel compressor
It is made of Aluminium.
It is non magnetic.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Titanium for high pressure applications. Plastic.
Cast and machined, held in lathe in a 4 jaw chuck set up and bore and reamed to size to
required size to suit turbine wheel and shaft assembly journal diameter. Removed and held in
lathe in a 4 jaw chuck set up and reset to face the face adjacent to bore.
The back face machined.
Compressor Wheel (Impeller)
Compressor impellers are produced using a variant of the aluminium investment casting
A rubber former is made to replicate the impeller around which a casting mould is created.
The rubber former can then be extracted from the mould into which the metal is poured.
Accurate blade sections and profiles are important in achieving compressor performance.
Back face profile machining optimises impeller stress conditions. Boring to tight tolerance
and burnishing assist balancing and fatigue resistance. The impeller is located on the shaft
assembly using a threaded nut.
To meet the demanding standards required by turbocharger manufacturers, it is essential to
have the best equipment and the highest possible control over the manufacturing process.
Copper mould cavities are used to make rubber patterns for any new types of wheel. This
ensures the most repeatable quality and definition and long tool life.
This enables patterns to be replaced after a set number of castings have been produced to
ensure that only prime quality patterns are used.
Metal preparation is paramount and the latest rotary degassing techniques are employed when
melting the aluminium to ensure the cleanest possible material.
A smooth flow of metal into the mould is essential to minimise turbulence which would
result in the formation of oxides. Technique of counter gravity pouring which is controlled by
Filtration techniques are employed as an additional precaution to eliminate oxides. An inert
atmosphere is also employed during the pouring process.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Modern heat-treatment units are used with rapid quench facilities for all castings.
Hot Isostatic Pressing is used where called for by customers. This process enhances the
microstructure and fatigue properties of the castings.
Compressor Wheel Castings – machined and balanced and ready for assembly to the
turbocharger. A state-of-the-art balancing machine has been installed to enable on-site
balancing to the high standards required by the turbocharger industry.
A High Integrity Process
This is a brief description of the process.
A rubber replica (or pattern) of the compressor wheel is produced in a metal die and this is
covered by a specially formulated plaster slurry, to form a mould. After hardening, the rubber
pattern is carefully removed, leaving the negative shape in the mould. The rubber patterns can
be used many times but the plaster mould is only used once.
Aluminium is melted and then introduced into the mould to produce the cast component.
After cooling, the plaster is removed from around the metal casting. The feeder system is cut
away from the casting which is then cleaned by blasting. The casting is then processed further
and finally heat-treated and inspected.
Depending on customer’s requirements, additional operations may include x-ray, dyepenetrant inspection, ultrasonic and other testing. Enhanced mechanical strength and fatigue
properties can be achieved using hot isostatic pressing (HIP).
Master Model machined using CAD data
Metal Mould used to produce Rubber Patterns
Rubber Pattern used to form the Plaster Mould
7. Snap ring
It is made from spring steel
You can feel it being springy, try to twist it springs back to its shape.
Carbon Steel (SAE1060-1090) - Carbon Spring
Steel: This steel is known for its high strength, and
reliability in retaining ring applications. Since carbon
spring steel is subject to corrosion, Rotor Clip treats
all such rings with a protective coating to ensure
some corrosion resistance. For long-term corrosion
protection, a zinc plating or non-metallic finish
should be applied over the steel.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Stainless Steel (PH15-7 MO) - Stainless Steel: PH
15-7 Mo is an extra strength corrosion-resistant steel,
capable of preventing atmospheric oxidation at
temperatures up to
900º F. It also offers the following advantages:1.
Minimal distortion due to unique heat-treating
process.2. A minimum of 225,000 psi for high
ultimate tensile strength.3. High creep strength. Note:
We reserve the right to substitute PH 17-7 stainless
steel material for PH 15-7 Mo on larger rings.
Stainless Steel (Type 420) - Stainless Steel Type
420:A less expensive alternative to PH 15-7. Since
general corrosion resistance for this material is less
than PH-15-7, use of this material depends upon the
Beryllium Copper (Alloy 25) - Berrylium Copper
Alloy # 25: Applications that require conductivity are
best served by this material. It is also characterized
by excellent
corrosion resistance and is particularly effective in
sea air and seawater atmospheres.
8. O-ring
It is made from Neoprene
Feels like rubber
Viton depends its usually for bit of cold, heat ,acid resistant
9. Seal insert
It's made of Stainless steel
It is non magnetic
Cast iron, aluminium, steel
Machined from a billet of stainless steel round or hollow bar in CNC lathe
Cast iron, aluminium, steel
10. Oil deflector
It is made of mild steel plate.
Visual assumption
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Usually tin with some form of rust preventative coating of zinc
11. Piston ring
It is made of cast iron
Visual assumption
Piston ring plays a role of sealing, so it is also called seal ring. The common material for
piston ring is alloy cast iron or nodular cast iron, such as QT60-2. Sometimes, it also uses
high quality carbon structural steel, such as 65Mn.
Piston Ring Manufacture
Grey cast iron and steel piston rings are manufactured in different processes. At FederalMogul grey iron piston rings are cast as individual rings in a noncircular shape; there are
other ring manufacturers who cut the individual rings from pots or cuffs. The rings are
generally machined to the required shape by means of double cam turning, a process in which
the ring blank, already axially ground, is copy turned simultaneously on the inside and
outside diameters. After a segment equivalent to the free gap is cut from the ring it assumes
the free shape that will give it the required radial pressure distribution when fitted into the
cylinder. Once inside the cylinder the ring is completely light tight on its outside diameter
Besides using double cam turning, ring blanks can also be shaped by machining the inside
and outside diameters separately. This involves cam turning the outside diameter of the
noncircular blank and machining the inside diameter with the ring in the compressed state.
The gap is cut out in a step between O.D. and I.D. machining. Heat forming as a means of
shaping piston rings should be mentioned to complete the range of options, but this process is
Steel piston rings are made from a profiled wire. The rings are first coiled into a circular
shape and then the gap is cut out. The necessary shape is obtained using a heat treatment
process in which the rings are mounted onto an arbor appropriately designed to impart.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Profiling of the running faces of taper faced, and slotted oil rings is carried out, depending on
the ring design, on automatic O.D. lathes or profile grinding machines using special profile
cutting tools before or after coating.
12. Thrust sleeve
It is made of tool steel
The purpose it is manufactured for.
High tensile steel 4140 grade
Hardened steel thrust collars and oil slingers are manufactured to strict tolerances using
lapping. End thrust is absorbed in a bronze hydrodynamic thrust bearing located at the
compressor end of the shaft assembly. Careful sizing provides adequate load bearing capacity
without excessive losses.
Machined from a billet of high tensile steel round or hollow bar in CNC lathe and hardened
by heat treatment
Hardened steel thrust collars and oil slingers are manufactured to strict tolerances using
lapping. End thrust is absorbed in a bronze hydrodynamic thrust bearing located at the
compressor end of the shaft assembly. Careful sizing provides adequate load bearing capacity
without excessive losses
13. Thrust bearing
It is made of brass
It is non magnetic, physical appearance
Aluminium, white metal, roller or cup and cone roller bearings
Machined from a billet of brass round or hollow bar in CNC lathe
14. Journal bearing
It is made of brass
It is non magnetic, physical appearance
Aluminium, white metal, ball bearing
Bearing Systems
The bearing system has to withstand high temperatures, hot shut down, soot loading in the
oil, contaminants, oil additives, dry starts.
Journal bearings are manufactured from specially developed bronze or brass bearing alloys.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
The manufacturing process is designed to create geometric tolerances and surface finishes to
suit very high speed operation
15. Shaft and turbine wheel assembly
Shaft is made from high tensile steel 4140 grade turbine wheel mixture of inconel
The purpose it is manufactured for.
Cast and friction welded and centres drilled on both ends, seal area including seal groove for
the piston ring, bearing and compressor journal ground to specifications. Thread for the lock
nut machined.
How is a shaft and wheel manufactured?
Perhaps the most vital component at the beginning of the manufacturing process is the
Inconel austenitic nickel-chromium-iron alloy turbine wheel, a high strength investment
Inconel is a material that manufacturing engineers dislike.
It is designed to withstand high temperatures, with an inevitable trade-off in machineability.
Therefore a casting process has been developed and progressively refined to provide a casting
profile that requires minimal machining.
In practice, the only turbine wheel machining undertaken inhouse is to ‘mass centre’ the hole
in the nose of the wheel.
As the name implies the hole is positioned at the centre of mass of the casting, not at its
geometric centre, in order to ensure perfect balance in the finished component.
The centre hole is used to locate the turbine wheel throughout the manufacturing processes.
Starting life as a steel forging, the shaft is friction welded to the turbine wheel.
Friction welding was developed in the 1980s as a relatively low cost and reliable welding
process, which proved ideal for attaching a turbocharger’s comparatively soft steel shaft to
the much harder turbine wheel investment casting.
More traditional welding techniques had proved less than satisfactory, but intensive
development of friction welding led to a process that is consistent and reliable.
During the process, friction between a rotating and a stationary component causes the two
metals to become red hot, at which stage pressure is applied to forge the parts together.
Typically the shaft length is reduced by 3mm during the process.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Quality is controlled by careful monitoring of the process parameters, notably speed and
pressure. To ensure effective process control, random samples of the conjoined turbine/shaft
component are regularly tensile tested to destruction.
Surprisingly, a typical friction welded joint with a surface area of only 2cm sq will take a
tensile load of over 10 tonnes before fracture.
Furthermore, the joint is usually stronger than the parent metal.
Welding is followed by turning the shaft diameters in a lathe prior to precision grinding to
finished tolerances.
Before grinding, the bearing diameter of the shaft is induction hardened to provide the
required durable surface match for the journal bearings.
Induction hardening produces a hard surface on the shaft up to 2mm deep, while retaining a
softer inner core in the shaft to maintain strength against potential shock load fracture.
Final grinding of shaft diameters is done on CNC (computer numerical control) grinding
machines able to work to the required size, straightness and roundness tolerances on all shaft
Quality is assured through the use of multiple function electronic gauges able to measure all
the vital dimensions simultaneously.
Statistical process control and calculation of the ongoing capability of the process is provided
at the same time.
After the shaft diameters have been finish ground, the turbine wheel profile must be
machined; another specialised Inconel machining operation.
The hardness of the material means that the profile must be ground.
Tolerances on size and concentricity must be maintained during the process to ensure an
accurate match between the turbine wheel and its housing, thereby guaranteeing consistently
high turbine efficiency.
Seal ring grooves in the hub of the shaft may be turned or ground.
Once again tight tolerances are essential on dimensions and surface quality as they influence
oil leakage control in the finished turbocharger.
Threads are then rolled on to the impeller end of the shaft. A strong concentric thread is
required to retain the impeller, especially so in the face of customer demand for increased
turbocharger performance necessitating larger impellers with small compressor clearances.
The final manufacturing operation is to balance the turbine wheel so that the shaft and wheel
assembly is capable of running at operating speeds without vibration or excessive shaft
movement in the bearing system.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
The shaft is dynamically balanced in two planes; at the nose and back face of the turbine
This is undertaken on semi or fully automatic machines that measure balance of the turbine
wheel, simultaneously calculating the precise amount of material required to be ground from
each plane of the turbine wheel to bring it into balance.
Almost every dimension on the shaft and wheel is critical to turbocharger performance and
The manufacturing tolerances being achieved today are close to the best achievable in any
volume manufacturing process.
Almost every dimension on the shaft and wheel is critical to turbocharger performance!!
16. Piston ring
Same as in Part 11.
17. Heat shield
It is made of stainless steel
It is non magnetic
Cast iron
Machined from a billet of cast iron round or hollow bar in CNC lathe
18. Bearing housing and pin assembly
It is made of Cast iron and pin of high tensile steel
Visual assumption
Bearing Housing
A grey cast iron bearing housing provides locations for a fully floating bearing system for the
shaft, turbine and compressor which can rotate at speeds up to 170,000 rev/min. Shell
moulding is used to provide positional accuracy of critical features of the housing such as the
shaft bearing and seal locations. CNC machinery mills, turns, drills and taps housing faces
and connections. The bore is finish honed to meet stringent roundness, straightness and
surface finish specifications.
18. Bearing housing and pin assembly
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Cast and machined, held in lathe in a 4 jaw chuck set up and reset on to machine compressor
housing and seal face mating diameter and faces machined. The bearing journals bores to
nearly size to only finish to specifications by honing and grooves machined to accommodate
circlips to hold journal bearing in place. Removed and held in lathe in a 4 jaw chuck held in
the other end and reset on to machine turbine housing / heat shield mating diameter and faces
and r
19. O-ring
Same as in Part 8.
20. Snap ring
Same as in Part 7.
21. V band
It is made of stainless steel
It is non magnetic
Can be made from cast iron
22 & 23. Turbine housing
It is made of cast iron
Stainless steel - fabricated
Turbine Housing
Turbine housings are manufactured in various grades of spheroidal graphite iron to deal with
thermal fatigue and wheel burst containment. As with the impeller, profile machining to suit
turbine blade shape is carefully controlled for optimum performance.
The turbine housing inlet flange acts as the reference point for fixing turbocharger position
relative to its installation. It is normally the load bearing interface.
Cast and machined, held in lathe in a 4 jaw chuck set up and reset on to machine bearing /
heat shield housing and mating seal face diameter and faces machined. The turbine wheel
exducer area bored and profiled. Removed and held in lathe in a 4 jaw chuck held in the
other end and reset on to machine gas outlet face.
Set up on the milling machine to mill the gas inlet face and also drill holes for mounting
Set up on the milling machine to machine wastegate bore and faces and bushing journal.
24. Heat protection lagging
It is made from heat resistant material cut out to desired shape and sewed together.
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
The purpose its designed for.
It can be formed from thin mild steel plate
25. Hose clamp
The majority manufactured hose clamps use stainless steel or lowgrade carbon steel components. The bands, screws and housings
can be made of zinc plated carbon steel with either a clear
chromate or yellow dichromate coating or of stainless steel 410,
201, 301, 302, 304, 305 or 316.
Hose PTFE lined flexible hose products are used all over the world in
automobiles, trucks, motorcycles and in motorsports and special purpose
vehicles. Applications include brake hose, fuel hose and oil hose for
hydraulic and fluid transfer lines.
The properties which make PTFE uniquely suited to these applications include high pressure resistance and
toughness, combined with a comprehensive ability to withstand the high operating temperatures, and the exotic
fuels and oils which are encountered in modern engines and vehicles.
The automotive hose product range is also used in a wide variety of general purpose applications, including
refrigeration equipment, high temperature / pressure steam and oil applications, high pressure gas transfer lines
and wherever the exceptional properties of PTFE lined hose products make all the difference.
27. Actuator
It is made from zinc plated thin mild steel plate and Part 30, which incorporates of a rubbers
diaphragm, a spring and a nut which are all assembled and the two pieces of the plates seam
jointed together.
28. Spring washer
Spring Washer Production
Production methods of spring washers include stamping, machining, hot forged, rolled, or
some combination of these. The following infographic explains common production protocol
for spring washers according to material and application requirements.
Some spring washers will undergo a slight, acceptable plastic deformation after its first
compression and it will not return to its previous height, though the washer is mechanically
sound. This is known as 'setting,' and a manufacturer may choose it preset the spring washer
in a process called scragging. Other production options include shot peening and adding
corrosion resistant coatings to enhance the spring washer's life.
29. Bolt
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Raw Materials
Screws are generally made from low to medium carbon steel wire, but other tough and
inexpensive metals may be substituted, such as stainless steel, brass, nickel alloys, or
aluminum alloy. Quality of the metal used is of utmost importance in order to avoid
The cold heading machine cuts a length of wire and makes two blows on the end, forming a
head. In the head slotting machine, the screw blanks are clamped in the grooves around the
perimeter of the wheel. A circular cutter slots the screws as the wheel revolves.
cracking. If a finish is applied to the screw, it must be of a compatible makeup. Steel may be
coated or plated with zinc, cadmium, nickel, or chromium for extra protection.
On a single thread screw, the lead and pitch are identical, lead is twice the pitch on a double
thread model, and three times as much on a triple thread. The pitch of a screw is the distance
between two threads (or grooves) from the same point on each thread. It is also more
commonly known as the number of threads per inch or centimetre. The lead of the screw
measures how far it is driven in for each revolution.
The Manufacturing
Machining is only used on unique designs or with screws too small to be made any other
way. The machining process is exact, but too time consuming, wasteful, and expensive. The
bulk of all screws are mass manufactured using the thread rolling method, and that is the
procedure described in further detail.
Cold heading
1 Wire is fed from a mechanical coil through a prestraightening machine. The
straightened wire flows directly into a machine that automatically cuts the wire at a
designated length and die cuts the head of the screw blank into a preprogrammed
shape. The heading machine utilizes either an open or closed die that either requires
one punch or two punches to create the screw head. The closed (or solid) die creates a
more accurate screw blank. On average, the cold heading machine produces 100 to
550 screw blanks per minute.
Thread rolling
2 Once cold headed, the screw blanks are automatically fed to the thread-cutting dies
from a vibrating hopper. The hopper guides the screw blanks down a chute to the dies,
while making sure they are in the correct feed position.
3 The blank is then cut using one of three techniques. In the reciprocating die, two flat
dies are used to cut the screw thread. One die is stationary, while the other moves in a
reciprocating manner, and the screw blank is rolled between the two. When a
centerless cylindrical die is used, the screw blank is rolled between two to three round
dies in order to create the finished thread. The final method of thread rolling is the
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
planetary rotary die process. It holds the screw blank stationary, while several diecutting machines roll around the blank.
Threads can be cut into the blank by several methods. In the reciprocal method, the
screw blank is rolled between two dies. In the cylindrical method, it is turned in the
centre of several rollers.
All three methods create higher quality screws than the machine-cut variety. This is
because the thread is not literally cut into the blank during the thread-rolling process,
rather it is impressed into the blank. Thus, no metal material is lost, and weakness in
the metal is avoided. The threads are also more precisely positioned. The more
productive of the thread-rolling techniques is by far the planetary rotary die, which
creates screws at a speed of 60 to 2,000 parts per minute.
Quality Control
The National Screw Thread Commission established a standard for screw threads in 1928 for
interchangeability. This was followed by an international Declaration of Accord in 1948,
adopting a Unified Screw Thread system. The standards focus on three main elements: the
number of threads per inch, the designated pitch and shape of the thread, and designated
diameter sizes. In 1966, the International Standards Organization (ISO) suggested a universal
restriction on threads to ISO metric and inch size ranges with coarse and fine pitches.
Compliance with the ISO suggested standards has been global.
30. Snap pin
Similar to part 1.
And the end being forged and flattened, a hole drilled for the Part 32, Lever Assembly and
then hardened so the it does not wears out often whilst in operation.
31. Nut
It is made from high tensile steel
The purpose it is manufactured for.
It can be can be manufactured such as nylock nuts.
32. Assembly lever
It is made from Nitronic 60 stainless steel
It is non magnetic and physical appearance
It can be made from high tensile steel
33. Bushing
Student: Jagdishwar Kishor 264964237
Teacher: Tim Lovett
Same as Part 32
34. Wastegate valve assembly
Same as Part 32
35. Gasket
Gaskets are made up of graphite, cellulose fibre, synthetic rubber that is used in sealing joints
exposed to high working temperatures
They are prepared by pressing the material to a designed width and then cutting into
appropriate shape and size required.
36. Cover
It is made of stainless steel, heat and corrosion resistant.
It is non magnetic
Can be made from high tensile steel plate.
Laser cut from a plate, three holes marked and drilled to 7 mm diameter for the mounting
37. Bolt.
Same as in Part 29.