Types of keys in machine design

There are different types of keys are available and there are a number of standards. 
Many ways to classify the keys. so let we check it out types of keys below :

• Saddle key and Sunk key
• Square key and Flat key
• Taper key and Parallel key
• Key with and without Glib-head

There are some special types of keys are also available. some of the special types of keys are given below :

• Woodruff key
• Kennedy key or Feather key 

This special types of keys are used in the following applications depending upon the following factors :

• Power to be transmitted
• Tightness of fit
• Stability of connection
• Cost 

Saddle key :

A saddle key is a key which fits in the key ways of the hub only there are no keyways on the shaft.

Saddle keys are suitable for light duty only. They tend to work loose rock on the shaft under heavy duty.

There are two types of saddle keys :

• Hollow saddle key
• Flat saddle key  

Hollow saddle key :

Hollow saddle keys is a taper key which fits in key ways in the hub and the bottom of the key is a shaped to fit the curved surface of the shaft. 

It is held on by friction, therefore suitable for light loads.

Flat saddle key :

Flat saddle keys is a taper key which fits in key ways in the hub and is flat on the shaft.

It is likely to slip round the shaft under load, therefore suitable for comparatively light loads.  

In both types of saddle keys friction between the shaft, key and hub prevent the relative motion between the shaft and the hub.

In case of the flat key, the resistance of slip is more than that of the hollow key, therefore flat saddle key is slightly superior to hollow shaft key as far as the power transmitting capacity is concerned.

Sunk key :

A sunk key is a key in which half the thickness of the key fits into the keyways on the shaft and the remaining half in the keyways on the hub.

In these keys, keyways are required both on the shaft as well as the hub of the mating element.

This is the standard form of the key.

In sunk key, power is transmitted due to shear resistance of the key.

The sunk key is suitable for the heavy-duty applications because there is no possibility of the key to slip around the shaft.

Square key and flat key :

Sunk keys are used in two ways :

• Square 
• Rectangular cross-section

A sunk key with rectangular cross-section is called a flat key.

The flat key is more stability as compared with the square key.

Square keys are used in general industrial machinery while flat keys are more suitable for machine tool applications.

Taper key and Parallel key :

A parallel key which is uniform in width as well as height throughout the length of the key.

A tapper key is also uniform in width but tapper in height.

Standard tapper is 1 in 100.

Tapper is provided due to the following reason :

• Due to tapper, it is easy to remove the key and dismantle the joint easily.
• Tapper insures tightness of joint in operating conditions and prevent loosening of the parts.

Glib-head key :

Glib keys are tapered and notched machine keys that are used on power transmission keyed shafts to hold pulleys and gears tightly on the shaft.

Taper keys are often provided with glib-head to facilitate removal.

Glib head key has following advantages as compare with parallel key, taper key :

• The taper surface results in wedge action and increases frictional force and the tightness of the joint.
• The taper surface facilitates easy removal of the key, particularly with glib-head keys.

Feather key :

A feather key is a parallel key which is fixed either to the shaft or to the hub and which permits relative axial movement between them. 

The feather key is a particular type of sunk key with uniform width and height.

Feather key used where the parts mounted on the shaft are required to slide along the shaft such as clutches or gear shifting devices. 

Feather key is an alternative to splined connection.

Woodruff key :

A woodruff key is a sunk key in the form of an almost semicircular disk of uniform thickness.

Woodruff keys are used on tapered shaft in machine tools and automobiles.

Advantages of woodruff key :

• It can be used on tapered shaft because it can align by slight rotation in the seat.
• The extra depth of key in the shaft prevents its tendency to slip over the shaft.

Disadvantages of woodruff key :

• The extra depth of key ways in the shaft increases stress concentration and reduces its strength.
• The key does not permit axial movement between the shaft and the hub.

Keys in machine design

Keys :

What is the key ?

• A key can be defined as a machine element which is used to connect the transmission shaft to rotating machine elements like pulleys, gears, sprockets or flywheels.

Key joints consisting of shaft, hub and key.

Keys may be made of plain carbon steels like 45C8 or 50C8.

Functions of key :

• To transmit the torque from the shaft to the hub of the mating element and vice versa.
• To prevent relative motion between the shaft and the joined machine element like gear or pulley.
• In some cases, it is also used to prevent axial motion between two elements in case of father key or splined connection.

A drawback of the key joint :

• The main drawback of a key joint is due to keyway stress concentration in the shaft and the part becomes weak.

There are different types of keys are available and there is a number of standards.

How front wheel drive works

In this article we have discuss about front wheel drive and how to work front wheel drive and its assembly.

Assembly of front wheel drive train :

In most of front wheel drive train have a transaxle. A transaxle combines the transmission and differential into one single unit.  
Because of all components are in front of the car front wheel drive vehicle don't need long drive shafts to transfer torque to the wheels. instead of this half-shaft is used. Half-shaft is connects with the transaxle to the wheel assembly.
Half-shaft connect with the transaxel to the wheel assembly with the use of constant velocity joints, or CV-joints instead of U-joints. 
CV-joints use a ball bearing mechanism to reduce the friction and to allow more complex wheel movement.

Do front wheel drive cars have differentials

Do front wheel drive cars have differentials ?

Answer 

• Yes, front wheel drive cars have differentials.

In front wheel drive it is integrated into the transmission casing and is not immediately visible.

In FWD cars the two half-shafts ( for each wheel ) of the trans axle go directly into the differential hub.

If you want to know more about front wheel drive drive-train CHECK IT OUT below article :

• Front wheel drive train assembly 

Can front wheel drive cars drift

Can front-wheel-drive cars drift?

Answer :

• No, front-wheel-drive cars not drift 

A little bit of drift can be induced in a front-wheel-drive car by pulling on the handbrake and locking up the back wheels. this drift is called braking drift and this is not the same as a power drift where the back wheels break traction due to extra power through the drive train from the engine. 

Power drifts can only be done if there is power at rear wheels.  

But yes, using an FWD car, a braking drift can be done with handbrake which hardly lasts for a couple of seconds.

Front wheel drive vs Rear wheel drive

In this article we have to look out for what was actually a front wheel drive and rear wheel drive
what is the difference between them and comparison between them as a price wise performance wise etc. 
Most of the car buyer's in today scenario first think about what car to buy in this article they have clear their confusion and buy according to their need.

Front wheel drive :

FWD is the vehicle where the motor drives only the front wheels of a car. 
Now a days most of the car manufacturers offers front wheel drive because it is cheap and easy to design and also light weight as it is devoid of extra transmission and axle assemblies..

Rear wheel drive :

RWD is the vehicle where the motor drives only the rear wheels of a car. 
In rear wheel drive an engine in front it connected to a transmission then power to rear-axel via driveshaft which drives the rear wheels.

Now we have to discuss normal priorities like space, fuel economy, price and easier drive ability, efficiency.

Space :
In front the space is same but in the back, front wheel drive trumps rear wheel drive because of the high transmission tunnel which makes seating three in the back a hard and uncomfortable thing to do. 

Fuel Economy :
Front wheel drive cars have better economy because there is less power lost in transferring the power from engine to the wheels.
But now with the help of technology rear wheel drive cars are closing the gap.

Price :
It's just easier to built front wheel drive cars because everything is so nearby the engine.
So front wheel drive vehicles are mostly cheaper than that of the rear wheel drive vehicle.

Efficiency : 
FWD cars have less weight & thus better mileage due to no drive shaft. 
Also a transverse motor & transmission eliminates a gearing transfer, again reducing weight & friction because of that the FWD are better efficiency. 

Drive ability :

If you are a calm driver the front wheel drive is for you.
If you are a speed lover kind of driver then I would suggest Rear wheel drive because if you drive a front wheel drive car hard then it cause understeers which means that your steering is now turned fully to go left or right direction but you are still ploughing forward in the same direction.
But in case of RWD if you were driving car and you drive its up to limits it may or may not oversteer which means that your cars end is coming out of the perfect apex line depending on the amount of power you have.

Oversteer is controllable &

Understeer is not 

So for we can see above both cars can understeer but there is more probability of it being a front wheel drive car.
And after I have said that it also means that both cars oversteer too.

So for calm driver go for front wheel drive 
Harsh driver go for rear wheel drive. 
But depending on how good you drive and if you need the rest of the things mentioned above.

Verdict on what car you buy : 
A normal car that sees everyday use, a front wheel drive car (FWD) is a much better choice.
FWD cars feature better packaging of its components so this cars allowing more room for passenger comfort and cargo. FWD cars also tend to be lighter and use smaller more fuel efficient engines. 
So if you look for family cars you can go for front wheel drive.

If you are speed lover a rear wheel drive or (RWD) car offers better performance dynamics for the driving enthusiast then you can go for rear wheel drive.

A front wheel drive is better for a normal car.
A rear wheel drive car is capable of powerful pickup.
More important thing is you can drift the car if you want so and it is used in sports car.
Performance wise it is better than FWD. 

Depending upon the pros and cons you also make out you confusion easily : 
You can check it out advantages of front wheel drive & disadvantages of front wheel drive.

You can also check it out difference between front wheel drive and rear wheel drive 

Rear wheel drive

What is rear-wheel drive?

• A transmission system that provides power to the rear wheels of a motor vehicle. 

In rear wheel, drive power is transferred to the rear wheels to move the car.

For the better part of the twentieth century, nearly every vehicle on the road had the engine sending power to the rear wheels. 

The most common setup in a rear-wheel drive vehicle involves the engine at the front of the car connected to a driveshaft to the differential that sends power to the rear wheel of the car. 

Assembly of rear-wheel drive train :

In rear-wheel drive cars the transmission is attached to the rear of the engine by way of a flywheel. Transmission what really happens when you press down on the accelerator? To understand this the drive- train may control the amount of power that goes from your engine to your wheels. 

The driveshaft is connected to the transmission and transmits the spinning power that began in the engine to the back of the vehicle at the differential.

While driveshaft designs are two types :

1. Torque tube 
2. Hotchkiss 

Torque tube driveshafts were used on older vehicles and trucks and SUVs used nowadays. Torque tubes connect the transmission and differential via a single universal joint is called U-joints.

Hotchkiss drive shafts are the common drive shaft design. Instead of just using one U-joint to connect the transmission and the differential, Hotchkiss drive shafts use two U-joints.

Then differential that sits between the two rear wheels. It is the last stop along the drive train before torque is transferred to the rear wheels.

If you want to know how the differential works check out the awesome video below :

Front wheel drive

What is a front-wheel-drive?

• A transmission system that provides power to the front wheels of a motor vehicle. 

In a front-wheel-drive vehicle power produced by engine directly transferred to both the front wheel of the vehicle.

In this layout, the engine drives the front wheels only and front-wheel can drive the real wheel of the vehicle.

Though the front-wheel-drive can be found is around 1929 where the engine is fitted in the front of the wheel, powering the front axle. it was the first front-wheel-drive automobile vehicle.

Many cars today use front-wheel drive. In front-wheel drive all the components of the drive train name transmission, differential and driveshaft are in front of the car. To fit all of this components in the front the engine is placed sideways in the car this is called transverse engine placement. 

Because all the parts of a front-wheel drive train are positioned at the front of a vehicle, you can make cars smaller and lighter or make the bigger cars but just have more room for passengers. 

Because of this more weight and traction are available at the front it provides more traction on slippery surfaces, like snow.

What really happens when you press down on the accelerator? To understand this you should know the drive-train assembly of front-wheel drive 

Assembly of front-wheel drive train :

In most of the front wheel, the drive train has a transaxle. A transaxle combines the transmission and differential into one single unit.  
Because all components are in front of the car front-wheel-drive vehicle don't need long drive shafts to transfer torque to the wheels. Instead of this half-shafts is used. Half-shaft is connected with the trans-axle to the wheel assembly.
Half-shaft connect with the trans-axle to the wheel assembly with the use of constant velocity joints or CV-joints instead of U-joints. 
CV-joints use a ball bearing mechanism to reduce the friction and to allow more complex wheel movement.

Nowadays a car buyer will also one thing keep in mind and make a comparison between Front-wheel drive (FWD) Vs Rear-wheel drive (RWD) cars and Front-wheel drive (FWD) vs All wheel drive (AWD) cars.

Castigliano's theorem

Italian engineer Alberto Castigliano developed a method of determining the deflection of structures by strain energy method.

He is known for his two theorems :

1. Castigliano's first theorem - for forces in an elastic structure
2. Castigliano's second theorem - for displacements in a linearly elastic structure.

We can discuss the second theorem below :

Castigliano's theorem statement : 

It is mainly used in machine design while designing shafts, keys and coupling.

• When a body is elastically deflected by any combination of forces or moments, the deflection at any point and any direction are equal to the partial derivative of total strain energy of the body with respect to the force located at that point and acting in that direction.

Castigliano's theorem is one of the important techniques for determining the deflection of a complex structure.

Castigliano's theorem is applicable only in the elastic range of the materials.

Procedure :

Steps :

1. Write an expression for each of the internal actions (axial force, bending moment, shear force, and torque) in each member of the structure in terms of external loads. 
2. Take derivatives of strain energy to get deflections and/or rotations.

For example :

Consider an elastic body subjected to a system of forces P₁, P₂, P₃ etc and U is total strain energy of the body. ∂1,∂2,∂3 are deflection at point of application and in direction of P₁, P₂, P₃ etc. then according to the theorem,

∂₁ = ∂U / ∂P₁

∂₂ = ∂U / ∂P₂

∂₃ = ∂U / ∂P₃

∂_I = ∂U / ∂P_i

Advantage and disadvantage of rigid flange coupling

Rigid flange couplings are commonly used in large, straight shafts where tight alignment tolerances must be maintained. In the power transmission industry, these couplings are very common and consist of two separate flanged halves that are bolted together. To ensure proper alignment and tight fit, the halves are keyed to the shaft with tapered keys. In situations where a strong coupling is required, a rigid flange coupling is often used, but there is little axial distance available. Let us have a deep insight into the pros and cons provided by this type of coupling. 

Advantages of rigid flange coupling :

• High torque transmitting capacity.
• Easy to assemble and dismantle.
• Simple in construction.
• Easy to design and manufacture.

Disadvantages of rigid flange coupling :

• It can't tolerate misalignment between the axes of two shafts.
• It is used only where the motion is free from shock and vibrations.
• It requires more radial space.

Hollow shaft vs Solid shaft

The hollow shaft contains the same amount of material all at the ends if hollow and a solid shaft are of the same weight whereas in the solid shaft distributed the material is uniformly throughout the shaft leaves little material at the ends. Difference between both of them is resistance to bending, resistance to torsion. Let us have a deep insight into the difference between the hollow and solid shaft.

Difference between the hollow shaft and solid shaft : 

• The material at the centre is removed in the hollow shaft and spread at large radius therefore, hollow shafts are stronger than solid shafts with the same weight.
• The stiffness of the hollow shaft is more than the same weight solid shaft.
• The strength of the hollow shaft is more than the same weight solid shaft.
• The natural frequency of the hollow shaft is higher than the solid shaft with the same weight.
• Hollow shaft is costlier than the solid shaft.
• The diameter of the hollow shaft is more than a solid shaft and require more space.
• Hollow shafts have a more polar moment of inertia, which enables them to transmit more torque than solid shafts.
• Hollow shafts do not transfer more power but the power to weight ratio of hollow shafts is more as compared to the solid shaft.
• Solid shafts, when subjected to bending, are stronger than that of the hollow shaft.

Depends on the application of the shaft :

Hollow shaft better for structural applications because it can beat the same loads as a solid shaft for lesser weight. Example: Rollcage of offroad vehicles.

The solid shaft is better for power transmission when compared to the hollow shaft. Example: Driveshaft

For the load-bearing type of shaft, it is always better to choose hollow shaft because it has higher stiffness and rigidity and can resist slightly higher bending moments. 

A shaft for transmission of torque like crankshafts, driveshafts, choosing a solid shaft is always better because it has higher torsional stiffness. 

Advantages and disadvantages of riveted joints

A rivet is a cylindrical mechanical joint that has a head. It is used as a member of the joint structure. It is a permanent joint which means that without failure of the machine component it can not be disassembled. This joint interference form fits the parts together. On the two plates, rivets apply a mechanical force that permanently joins the plates. Let us have a deep insight into the pros and cons of riveted joints in this article. 

Advantages of riveted joints :

• A riveted joint is more reliable than welded joints in applications which are subjected to vibrations and impact forces.
• Riveted joints can be used for non-ferrous metals like aluminium alloy, copper, brass or even non-metal like plastic and asbestos.
• Riveted joints are free from thermal after-effect because no heat required in this joint.
• Quality inspection is easy in a riveted joint.
• When the riveted joint is dismantled, the connected components are less damaged as compare to a welded joint.

Disadvantages of riveted joints :

• The material cost of a riveted joint is more.
• The labour cost of riveted joints is also more than that of the welded joint.
• Overall cost if the riveted joint is also high.
• The riveted assembly has more weight than the welded assembly.
• The riveting process creates more noise because of hammer blows.
• Holes required to insert rivets cause stress concentration.
• Production time is more for assembly.
• Riveted assemblies are not tight and leak proof.
• The projection of the riveted head adversely affects the appearance of the riveted structure.

Coarse threads vs Fine threads

The threads are divided into two categories such as coarse and fine series. The thread profiles of both the thread are generally similar but there has some minor difference between them. Let us have a deep insight into the comparison between coarse and fine threads. 

Both the screw threads are designated by the letter M followed by the value of the nominal diameter in mm. Example: M 12 

Difference : 

• Course thread has higher peaks and valleys than fine thread making them harder to strip.
• Fine thread is harder to loosen by vibration to its tighter coiling and they also require less torque to achieve the same holding power as a coarse thread would.  
• The height of coarse thread is greater than the corresponding fine thread so there is more material between each thread-making flank engagement greater.
• Coarse threads are less susceptible to being nicked or damaged, so they do not have to be handled with care as much as fine threads. 
• Coarse threaded fasteners are much faster to install than fine threaded fasteners.
• Coarse threads are not affected as much as fine threads by plating buildup.
• Fine threaded bolts of the same hardness are stronger than the corresponding coarse threaded bolts.
• Due to their smaller helix angle than coarse threads, fine threads tend to loosen under vibration.
• To develop equivalent preloads to the corresponding coarse thread bolt sizes, fine threads require less tightening torque.

Comparison according to advantages : 

Advantages of coarse threads :

• Easier to cut as compared to fine threads.
• It has more even stress distribution.
• During tightening, coarse threads are less likely to seize.
• The capacity of coarse threads to carry static load is higher.
• The manufacturing error is lower in coarse threads.
• Wear has less effect than fine threads on the strength of coarse threads.

Advantages of fine threads :

• Greater strength when subjected to fluctuating loads.
• Because of the lower helix angle, greater resistance to unscrewing.
• More reliable in terms of self-unscrewing than coarse threads.

Summary : 

Coarse threads are used for general industrial applications that are vibrations free while fine threads are used in the parts that are subjected to dynamic loads and vibrations.

Difference between set screw and cap screw

What is set screw?

A type of screw that is normally used to secure an object within or against another object without using a nut is called a set screw. Example: Secure a pulley or gear to a shaft. 

What is cap screw?

A cap screw is a type of screw with a cylindrical head and hexagonal drive hole is also known as a socket head cap screw. 

Let us have a deep insight into the difference between set and cap screw. 

Difference :  

• Setscrews are subjected to compressive force only while cap screw is subjected to tensile and shear forces also.
• Setscrew transmits force from threaded components to the other mating component by means of screw point but in case of a cap screw, the force transmitted only by the head.
• Setscrews are short and threaded over the full length of the shank as compared to cap screw.

Disadvantages of threaded joints

Threaded joints are widely used in mechanical assemblies its been like 60% of the parts have made by threads. Some advantages are due to the popularity of threaded joints.

Let us have a deep insight into the disadvantages provided by a threaded joint below. 

Disadvantages of threaded joint : 

• Threaded joints require holes in machine parts for clamping because of that stress concentration near the threaded portion of the parts it causes fatigue failure too in some case.
• Threaded joints loosen when subjected to vibrations.

Advantages of threaded joints

Threaded joints are widely used in mechanical assemblies its been like 60% of the parts have made by threads. Some advantages are due to the popularity of threaded joints.

Let us have a deep insight into the advantages provided by threaded joint below. 

Advantages of threaded joints : 

• Threaded joints are reliable joints no loosening of the parts that are held together by means of large clamping force.
• The parts are assembled using a spanner and the spanner length is large compared to the thread radius, so the mechanical advantages are greater and the force required to tighten the joint is small.
• It has small overall dimensions resulting in a compact construction.
• The threads are self-locking in order to place them in any position (also vertical, horizontal or inclined).
• For the threaded components, high accuracy can be maintained.
• Manufacturing of thread is very simple.
• The thread can be easily detached when needed in threaded joints.

Advantages of friction clutch

A friction clutch transmits the power by means of friction developed between contacting surfaces. The friction surface is flat and perpendicular to the axis of rotation. Single plate and multi-plate, centrifugal clutches and cone clutches are an example of this type of clutch. Now, let us have a deep insight into the advantages provided by a friction clutch. 

Advantages of friction clutch :

• The engagement is smooth.
• Power loss and consequent heat generation do not create problems because of slip occur only during engaging operation.
• Once the clutch is engaged, there is no slip between the contacting surface.
• Friction clutch serves as a safety device.
• In friction clutch wear is low.
• Capable of transmitting partial power. 
• Minimum shock during the engagement. 
• Easy to operate. 

Difference between rigid and flexible coupling

What is Rigid coupling?

Rigid coupling some cases called sleeve or muff coupling are economical and mostly designed for the aligned shafts only. 

What us Flexible coupling?

A flexible coupling is used to transmit torque from one shaft to another which is slightly misaligned. 

Let us have a deep insight into the comparison between the rigid and flexible coupling. 

Difference between rigid and flexible coupling :

• Flexible coupling couple with rotating members such as motors and driveshafts, while allowing misalignment in either angular or parallel offset orientation while rigid coupling couple with rotating members such as shafts. 
• A rigid coupling is simple and inexpensive while the flexible coupling is comparatively costlier due to additional parts.
• A rigid coupling can not tolerate misalignment between the axis of shafts used only when there is precise alignment between two shafts while flexible elements like bush or disk can tolerate 0.5⁰ of angular misalignment and 5 mm of axial displacement between the shafts.
• The flexible elements in the flexible coupling absorb shocks and vibrations while the motion is free of shocks and vibrations in the rigid coupling.
• Rigid couplings have limited application compared to flexible couplings because rigid couplings do not have the ability to compensate for shaft misalignment and are therefore used where shafts are already positioned in accurate lateral and angular alignment.
• Rigid coupling does not allow for angular or parallel misalignment while flexible coupling does.
• Deflection is less in rigid coupling while flexible coupling has more.

Explore more information : 

• Why flexible coupling is preferred over rigid coupling?
• What is coupling?
• What are the disadvantages of muff coupling?

Hot working vs Cold working

What is hot working?

Metal deformation process that is carried out above the recrystallization temperature is called a hot working process.

What is cold working?

Metal deformation process that is carried out below the recrystallization temperature is called a cold working process.

Now one question arises in your mind that what is re-crystallization temperature?

The temperature at which the metal formed new stress-free grains is called the temperature of re-crystallisation.

Let us have a deep insight into the comparison between the hot and cold working process. 

Difference between hot and cold working : 

• Hot rolled components have higher toughness and ductility while cold rolled components have higher hardness and strength.
• The dimensions of cold-rolled parts are very accurate as compared to hot rolled.
• Hot-working requires expensive tools while tooling required for cold working is comparatively inexpensive.
• Hot-working reduces residual stresses in the component while cold working induces residual stresses in the component.
• Cold worked components have a better surface finish than hot rolled parts.
• In the hot working process risk of the crack is less while in the cold working risk of the crack is more.
• Internal and residual stresses are produced in the cold working process while not produced in hot working.
• Hot-working requires less energy for plastic deformation because at higher temperature metal become more ductile and soft while cold working requires more energy for plastic deformation.
• Heavy oxidation occurs during hot working so pickling is required to remove oxide while pickling is not required in cold working because no oxidation takes place in this process.
• Material is uniform after the hot working process while the material is not uniform after the cold working process.
• The cold working process can easily maintain better tolerance while hot working not. 
• Hot-working refines metal grains resulting in improved mechanical properties while most of the cold-working processes lead to distortion of grains. 
• Due to recrystallization, very negligible Harding of metal takes place in hot-working on the other hand, metal gets work hardened in cold-working. 
• The stress required for deformation is much less in case of hot-working due to higher deformation temperature and stress required is more in cold-working for deformation. 

Advantages and disadvantages of sand casting

Sand casting is the most popular casting process among all of the casting process. Typically relies on silica-based materials. Casting sand consists of finely ground, spherical grains that can be tightly packed together into a moulding surface. The casting designed to reduce tearing, cracking by allowing a moderate degree of flexibility and shrinkage during the cooling phase. Many automotive products, such as housings, engine blocks are manufactured by this process. Let us have a deep insight into the advantages and disadvantages of sand casting to know more about it. 

Advantages of sand casting:

• Almost all types of alloys can be cast by this process as they melt and are pourable. 
• Sand casting is the cheapest methods of manufacturing. As the cost of equipment is low because only sand and reusable patterns are involved. 
• The tooling required for the casting process is relatively simple and inexpensive.
• Any component with a complex shape can be cast easily even large components too.
• Creep-resistant metal-based alloys for gas turbines are not mechanically workable and can only be cast.
• Dimensional accuracy in the range of +-0.8 to 3.2 mm. 
• Sand casting can be used to produce virtually any size part from a piston trigger to an engine block.
• The process is highly adaptable and can be used for mass production. 
• The lead time to make the mould short, and making sand casting ideal for short production runs. Therefore, a high production rate. 
• This process creates an isotropic structure. 

Disadvantages of sand casting: 

• A lower degree of accuracy than an alternate method. 
• This process tends to yield products that have a comparatively rough surface finish.
• Low material strength due to porosity. 
• Surface finish dimensional accuracy is very poor. 
• Defects such as shrinkage, porosity, surface defect, pouring metal defects are unavoidable. 
• The secondary machining process is required if close tolerance is required. 
• Due to it is backing process, use the extra time, labour. 
• This process is now suitable for large with heavy size casting as they are hard to back.

Thus, sand casting process may be a cheaper alternative to investment casting and can provide much more complex shapes, get the same accuracy, finish, and overall part quality. 

Explore more information:

1. What is sand casting process?