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Maintenance of Mechanical Systems

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0Unit 24: Maintenance of Mechanical Systems
1; the name of the machine and specification,
Clark 300 metal lathe machine
2; an explanation of the purpose of the document,
For this assignment I will explain the characteristics and properties and maintenance of two types of
lubrication that will be used to lubricate the Clark 300 metal Lathe machine. The lubrications I will be
explaining will be that one of the lubricants is a liquid lubrication and the other lubricant is a lithium
lubricant. Lubricating oil, sometimes simply called lubricant/lube, is a class of oils used to reduce the
friction, heat, and wear between mechanical components that are in contact with each other.
Lubricating oil is used in motorized vehicles, where it is known specifically as motor oil and
transmission fluid. Moreover the use of lithium lubricant is that it is thick which allows it to last on
the long term. It also has a high viscosity formula which allows for the lubricant not to drip or run, it
works well under pressure which is ideal for load bearing connections and it reduces friction and
wear. The lithium lubricant can also be used for things such as outdoor things not matter the
condition or the temperature this is one of the reasons it is useful for the tail stock.
3, a description of the purpose of each of the mechanisms examined,
The purpose of the gear box is that it is used to increase torque while reducing the speed of a prime
mover output shaft (e.g. a motor crankshaft). This means that the output shaft of a gearbox rotates
at a slower rate than the input shaft, and this reduction in speed produces a mechanical advantage,
increasing torque. Also the purpose of the gear box is that it allows you to have control over the
rotation, speed and their use in a metal lathe machine is no exception. The gear box contains many
different elements so that the gearbox runs correctly and efficiently. The components it contains are
counter shaft, main haft, gears and bearing. The counter shaft is a shaft that connects with the
clutch shaft directly, the gears that connects the shaft as well as the main shaft. The main shaft is a
shaft that runs at the speed of the machine and the main shaft gives power from the counter shaft
by the use of gears, according to the gear ration this allows it to run at various different speeds. The
use of the gear is to transmit power from one shaft to another shaft effectively. This is a useful
component of the gear box because the variation is torque of the counter shaft and main shaft that
depends on the gear ration. The bearing rotational motion encounters, bearings are required to
support the revolving part so that it reduces the amount of friction. In the gearbox both counter and
main shaft are supported by the bearing and the tail stock is used to apply support to the
longitudinal rotary axis of work piece that is being machined.
4, a description of the purpose of the lubrication together with a sketch of the system. This could
be a schematic diagram of the system,
In the picture you are
able to see me
applying lithium
lubricant on the lead
screw.
In the picture I
applied mineral oil
lubricant using the
oil so that I can
apply it on the
gear box also, I
had to make sure I
applied the
lubricant all over
the gear box so
that it runs
smoothly.
5,A section that states the lubricant in use and the properties of that lubricant, together with
possible alternatives that could give the same degree of protection,
From researching about both oil lubricant and lithium lubricant there is an alternative lubrication
that I could use. The alternative lubricant I could’ve used is powder lubricant, the lubricant has a
higher temperature than liquid and grease lubricants operate. Powder lubricant is used in
applications such as locks or dry lubricated bearings.
6, an evaluation of the lubrication system in use and an evaluation of the lubricant in use which
includes the alternative lubricant and its suitability as a replacement,
Whilst researching about the lubricants that I will be using on the lathe machine, the lubricants I
would be using is lithium grease and mineral oil. From my research I have found out that lithium
grease has a high melting point which is roughly around 199 degrees to 220 degrees. Also, lithium
grease has a high viscosity which means that it is much better at maintaining a firm strength and the
oil pressures at high temperatures. An advantage of using lithium grease is that once you apply it on
a work piece you won’t need to apply it again after a certain amount of time which allows you to
save time rather than continuously applying the lubricant. However I also found a disadvantage of
lithium grease that it has a high viscosity which means it needs more time to be in affect also needs
more energy when applying the grease. On the other hand from my research I found out the
benefits and limitations of mineral oil lubricant the properties of mineral oils are that they have
good resistance to oxidations but on the oxidations, it forms acids meaning when they are burnt it
could leave a hard-carbonaceous deposit on the gears of the lathe machine. Furthermore, the
mineral oil also has a good thermal stability and high flash point. The reason why this lubricant is
suitable for the gear box in the lathe machine is because it can get through the tight spaces between
the connecting of the gears towards each other.
7, a concluding section that make recommendations in respect of potential changes to the
lubrication system and the lubricant that is being used.
Whilst researching I found an alternative lubricant that can give the same degree of protection as
lithium grease and mineral oil which was powdered lubricant. Powdered lubricant can be used in the
lead screw and the gear box so that it can lubricate both the lead screw and gear box so that it works
efficiently. Powdered lubricant is mainly used in locks or dry bearings.
Specification
Motor..................................................................... 230VAC, 50Hz, 1 Phase Power
Power Rating............................................... 300Watts
Current Rating............................................. 5Amps
Distance Between Dead Centres...................... 300mm
Centre Height ...................................................... 90mm
Max. Work Diameter............................................ 180mm
Spindle Bore ......................................................... 20mm
Spindle Taper........................................................ No.3 Morse Taper
Tailstock Taper...................................................... No.2 Morse Taper
Cross Slide Travel.................................................. 65mm
Compound Slide Travel....................................... 55mm (effective)
Spindle Speeds .................................................... 100 to 2,500 RPM
Overall Dimensions .............................................. 820x295x300mm
Weight................................................................... 40kg
Screw Threads - Imperial .................................... 12 - 104 TPI in 26 steps
Metric ....................................... 0.4 - 2.0mm pitch in 10 steps
Lithium grease:
While researching all the lubricants the lubricants are known to have a high lubricity and oiliness.
The property of the lubrication comes from a chemical compositions of the oils which allow it to
reduce the wear and friction even in extreme conditions. The viscosity index (VI) is an arbitrary, unit
less measure of the change of viscosity with temperature, mostly used to characterize the viscositytemperature behaviour of lubricating oils. The lower the VI, the more the viscosity is affected by
changes in temperature. Moreover, viscosity is a measurement of a fluids thickness or resistance to
flow.
Most of the lubricants are formulated with additives such as lithium grease that can form chemicals
bonds with surfaces or that exclude moisture so that it can prevent any sort of corrosion or rust on
the equipment, it also reduces carrion between surfaces so that it can avoid immersed corrosion.
Additive package are the major components in grease formulations as such exert considerable
influence on the reaction of the grease. The thickener is often referred to as a sponge that hols the
lubricant, base oil plus. The thickness of the lithium grease prevents the lubricant from dripping of
the surface of the lead screw meaning that it has high viscosity as one of the properties. The lithium
grease oil has another advantage which is that it can be used on a reasonable speed application or in
this case the lead screw of the lathe machine because it works on temperature that is within the
limit of the lithium grease oil. Lithium based greases are the most commonly used, sodium and
lithium based grease have higher melting than calcium based greases but are not resistant to the
action of water. Lithium based grease has a dropping point at 199 to 220c, 350 to 400f. This lubricant
provides great protection for heavy duty, metal to metal applications. It can be used for outside
weather and temperature conditions. The high viscosity water resistance formula won drip or run
remaining where it applied through all weathers and through temperatures from –18 to +145c. This
is ideal for automotive connections, tow bars, gears, brake mechanisms and cv joints.
Lastly, the grease oil has another property called pump ability which is the ability of the lithium
grease to be pumped or pushed through a system. More practically, pump ability is the ease with
which a pressurized grease can flow through lines, nozzles and fittings of grease-dispensing systems.
Maintenance considerations:
Whilst using lithium grease I need to assure that I maintain it in good conditions or it won’t be
efficient. The first thing before applying it is to make sure that it hasn’t expired so that I know it is
good to use and if it has passed the expiry date that means it will lack consistency which would
affect the lead screw when I apply the grease on the lead screw so I would make sure that you
reapply the lithium grease on the lead screw once every week because of its thickness.
Lubrication processes:
Before I even start to lubricate the lead screw I need to make sure that I must wear the correct PPE
equipment to make sure I am safe whilst I apply the lubrication. Before I start to lubricate I need to
make sure I have on a lab coat, googles and some gloves so that when we are applying the grease it
doesn’t need to be on your finger. So the first step when applying the grease would be you get the
grease and put it on your finger then you get your index finger and gently apply the grease onto the
lead screw from a right to left motion so that you grease the whole lead screw.
Mineral oil:
Mineral oil is any of various colourless, odourless, light mixtures of higher alkanes from a mineral
source, particularly a distillate of petroleum. Mineral oil is a transparent, colourless oil, composed
mainly of alkanes and cycloalkanes, related to petroleum jelly. Mineral grease produced nowadays
use mineral oil as fluid components. These mineral oil based greases typically provide satisfactory
performance in most industrial applications. In extremes temperatures low or high, a grease that
utilises a synthetic base oil will provide better stability. The mineral oil has a low viscosity which is a
measurement of a fluid`s thickness or the resistance to flow. This means that the mineral oil would
pour more easily at a low temperature which is extremely important when applying it onto the gears
in the gear box of the lathe machine because there would be missing gaps where the grease oil or
any other lubricant can reach also it takes less energy to move the gears in the box through the oil.
Mineral oils lubricant has a great corrosion and oxidations resistance because under any other
lubricants circumstances the lubricant are exposed to oxygen in the atmosphere and certain metals
or compounds at the temperature above 71.1 Celsius degrees, they can be prone to oxidations. If
the lubricant start to oxidation it can lead to several undesirable consequences such as increased oil
viscosity, formations of acids start to emerge, and sludge build up in the lubricants. The selection of
oil viscosity for any bearing application requires consideration of several factors; load, speed,
bearing setting, type of oil and environmental factors. Since oil viscosity varies inversely with
temperature, a viscosity value must always be stated with the temperature at which it was
determined.
Maintenance considerations:
Before we apply the mineral oil to the gears in the gear box of the lathe machine we have to have
some sort of sign of deteriorations, for instance if there is a change in the texture and the odour.
Due to the thinness of the lubricant I would recommend applying the lubricant to the gear box twice
a week with the mineral oil lubricant so that it is well greased and working correctly.
Lubrication processes:
The lubrication process of mineral oil is just like the lubrication process of lithium grease however
there is a slight difference. Before lubricating the gear box you must ensure that you are safe so you
must wear the appropriate clothing such as lab coat, goggles and gloves to prevent anything
happening. Whilst applying the grease you need to hold the canister firmly and steadily and then you
must gently pour the lubricant above the gear box and let the mineral oil go through the gear box
onto the lathe machine so that the gear box is properly lubricated.
For this task you should evaluate the lubrication process, properties, maintenance consideration,
and the environment application of mineral oil and lithium greases and suggest an alternative
lubricant and its suitability as a replacement, in terms of it properties and lubrication processes.
The advantage of using lithium grease is that it acts as a sealant to minimize leakage and to keep out
as contaminants because of that it has a consistency, grease acts as a sealant to prevent entrance of
corrosion contaminants and foreign materials. Most of the lubricants are formulated with additives
such as lithium grease that can form chemicals bonds with surfaces or that exclude moisture so that
it can prevent any sort of corrosion or rust on the equipment, it also reduces carrion between
surfaces so that it can avoid immersed corrosion. Additive package are the major components in
grease formulations as such exert considerable influence on the reaction of the grease. The
thickener is often referred to as a sponge that hols the lubricant, base oil plus. The thickness of the
lithium grease prevents the lubricant from dripping of the surface of the lead screw meaning that it
has high viscosity as one of the properties it also acts so that it is deteriorated seals effective.
Lithium based grease has a dropping point at 199 to 220c, 350 to 400f. This lubricant provides great
protection for heavy duty, metal to metal applications. It can be used for outside weather and
temperature conditions. The high viscosity water resistance formula won drip or run remaining
where it applied through all weathers and through temperatures from –18 to +145c. This is ideal for
automotive connections, tow bars, gears, brake mechanisms and cv joints. Whilst researching about
the lubricants that I will be using on the lathe machine, the lubricants I would be using is lithium
grease and mineral oil. From my research I have found out that lithium grease has a high melting
point which is roughly around 199 degrees to 220 degrees. Also, lithium grease has a high viscosity
which means that it is much better at maintaining a firm strength and the oil pressures at high
temperatures. An advantage of using lithium grease is that once you apply it on a work piece you
won’t need to apply it again after a certain amount of time which allows you to save time rather
than continuously applying the lubricant. However I also found a disadvantage of lithium grease that
it has a high viscosity which means it needs more time to be in affect also needs more energy when
applying the grease. Lithium grease holds solid lubricants in suspension. Finely ground solid
lubricants, such as molybdenum disulphide (moly) and graphite, are mixed with grease in hightemperature service or in extreme high-pressure applications. Grease holds solids in suspension
while solids will settle out of oils. Fluid level does not have to be controlled. However lithium grease
also has limitations such as, On the other hand, dry lubricant has poor self-healing properties. A
broken solid film tends to shorten the useful life of the lubricant, poor heat dissipation. This
condition is especially true with polymers due to their low thermal conductivities and finally thermal
expansion can be very different to the metals that are being lubricated. Therefore, the loss of
desirable mechanical clearance has a chance of occurring whilst the process elevates or the
temperature reduces.
The advantage of using mineral oil lubricant is that it has a better solubility with additives, enhanced
compatibility with seals and lower cost, synthetic based lubricants can offer advantages such as a
greater tolerance for extreme temperatures. Mineral oils lubricant has a great corrosion and
oxidations resistance because under any other lubricants circumstances the lubricant are exposed to
oxygen in the atmosphere and certain metals or compounds at the temperature above 71.1 Celsius
degrees, they can be prone to oxidations. If the lubricant start to oxidation it can lead to several
undesirable consequences such as increased oil viscosity, formations of acids start to emerge, and
sludge build up in the lubricants. The selection of oil viscosity for any bearing application requires
consideration of several factors; load, speed, bearing setting, type of oil and environmental factors.
Since oil viscosity varies inversely with temperature, a viscosity value must always be stated with the
temperature at which it was determined. However mineral oil is not environmentally friendly oil
because it doesn’t biodegrade well which means it’s not a renewable resource that you can use
again.
Throughout my research I also was able to find an alternative lubricate I could’ve used lubricating
the lathe machine with. The alternative lubricant I could’ve used is dry lubricant or a solid lubricant.
The two main dry lubricants are graphite and molybdenum disulphide. Solid or dry lubricant
lubricants are useful for conditions when conventional lubricants are inadequate, such as:
Reciprocating motion. A typical application is a sliding or reciprocating motion that requires
lubrication to minimize wear, as, for example, in gear and chain lubrication. The lubricant has a
higher temperature than liquid and grease lubricants operate. They can survive under extreme
conditions that liquid petroleum lubricants couldn't. Dry lubricants can also serve as thinner friction
barriers for parts to work better. Dry lubricants are often used in applications such as locks or dry
lubricated bearings. One example of a dry lubricant is graphite. With graphite the electrons can
move through the graphite, carrying charge from place to place and allowing graphite to conduct
electricity. Graphite is used as a lubricant due to its slippery nature. Graphite has layers of carbon
atoms, with weak forces, residing in between its layers because of which it is quite slippery.
Powdered lubricant has a high resistance to deterioration in storage which means it is less likely to
deteriorate and last for long. However, powdered lubricant has poor self-healing properties which is
a broken solid film that tends to shorten the useful life of the lubricant also, it has a poor heat
dissipation this condition is true with polymers due to their low thermal conductivities.
To conclude everything before choosing which lubricate you would use, you must know the
demands and circumstances of the application you will be using it on and what the temperature
would be like to decide which one is best for it. The things to look for is things such as if the
application requires a specific standard like the viscosity, operating-temperature range and the need
to wear protection. From considering this you must be able to choose which one meets the
requirements and what the suitable lubricant to use is. Whilst lubricating the Clark 300 metal lathe
machine I decided to use mineral oil on the gears not the lead screw because of its high viscosity this
would affect the lead screw because it will take a longer period of time to be in affect so I would use
mineral oil on the gears so it can evenly spread. However I used lithium grease on the lead screw
because it is much thicker so therefore it will have a better protection since the lead screw is
exposed to oxygen and other particles.
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