Industrial automation nowadays is very important especially anticipated to globalization and competition that industries need to deal with. The main purpose when applying this system is to raise the production rate without increasing the expenditures. For instance a certain activity that usually needs 3 employees to be achieved, by producing automation the same job can now be done by an individual robot and maybe one worker simply for supervision. After that the quality of product and also the production rate (products each hour) can be better. The three types of commercial automation are programmable, flexible and fixed automation.
Figure 1: Variety vs. Amount for the 3 types of automation
Figure 1 shows the difference between the three types of automation. Immediately one can notice that programmable automation allows deviation while sacrificing volume and fixed automation allows large quantities to be produced restricting variation. Fixed automation stands in the center of both.
1. 1) Programmable Automation
Programmable automation allows reprogramming of the machines to fulfill different sequence of procedures. Different products require different process to be achieved for the developing processes. When a company handles customised products such as HVAC units the machines have to be programmed to fit the customer's needs. If the client requires that the HVAC product must be installed in a certain part of the building then the HVAC's dimensions have to be customised therefore the machines have to be reprogrammed to gratify the customer's needs. Apart from that, if the HVAC product is going to be installed in a very cold climate region than heat exchanger needs to vary than the one's installed in Malta.
A company using programmable automation must spend a high amount of money to choose the equipment and also needs workers to program these machines. The personnel have to be trained and also be skilled enough to program the machines in the least time possible. The creation rates are less than the other two types of commercial automation and production is done in batches. As mentioned above programmable automation can deal with customised products this means changes in the products are possible.
1. 2) Flexible Automation
In versatile automation which is normally found in the automotive industry allows little variance when compared to programmable automation. The benefit is usually that the production rates are higher.
In an motor vehicle industry the same model of a specific car may differ in colour, engine, wheels, interior etc. Therefore this is excatly why the automation must be flexible. Exactly the same equipment and same programs are used but requires some changeover from one job to some other. Automotive companies need to get a great deal of money on the machinery but the amount is significantly less than programmable automation. The development is continuous in support of short amount of time is lost during changeover. The creation rates are lower than fixed automation but as discussed allow some variant unlike fixed automation.
1. 3) Fixed automation
A company that produces newspaper can be considered as fixed automation. In fixed automation the product produced is set and only a small tolerance for variation is allowed hence the word fixed.
This type of automation usually ends up with high development rates and large levels of the merchandise produced. Therefore the money spent on machinery is small when compared to the money earned by the amount of products produced. The major downside as stated above is having less variance which sometimes can limit the company in producing other products because the equipment design and programs can't be easily transformed.
2) What is the difference between perfection and reliability regarding way of measuring?
Nowadays on the market many kind of sensors are present and also one may choose from a wide variety of brands. One important factor is that the sensor being bought is specific and exact.
If a temps sensor reads 23oC and the true true value is 25oC then there is an mistake of 2oC. Therefore which means that the sensor is not correct that can be essential on certain kind of installations.
On the other hand if the temperature sensor reads 23oC so when assessed for another couple of times the temps always differs, than the senor is not correct.
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Figure 2: Perfection vs Accuracy and reliability
Figure 2 shows a diagram which can demonstrate what has been said above. Starting from the right the prospective shows an example of using a sensor which is neither exact nor exact. The dark-colored dots stand for the readings which can be far away from the prospective (not correct) and they are also far away from each other (not correct). The remaining aim for shows a representation of your sensor which is not correct but precise which is why the readings are far away from the mark but near each other due to precision. The center target represents an ideal sensor being both accurate and exact. The black dots are at the heart and also next to one another.
3) Tension Gauges
a) Explain the principle of strain way of measuring using strain gauges.
Strain gauges are being used in receptors to measure push and related parameters such as torque, acceleration, pressure and vibration.
A strain measure has its electrical resistance which is varied when these devices is subjected to strain. Therefore the more strain the more electrical resistance mixed which then provides reading of the existing forces on the task piece. The bonded metallic strain gauge is most commonly used. This involves skinny metallic foil fixed in a grid pattern which is bonded to a thin backing (carrier) and then attached to the work part. When the work piece is subjected to strain then it is transferred to the strain measure which varies its electrical level of resistance and can give the reading necessary.
b) Supply the schematic for some common way of measuring set-up for this type of dimension.
Figure 3 shows the schematic of the most commonly used strain measure (quarter bridge circuit). For the strain to be measured which includes really small values, an accurate measurement is needed to measure the small changes in resistance. This setup is named a Wheatstone bridge. It contains four resistive hands with an excitation voltage "Vex" which is applied over the bridge. When there's a change in amount of resistance in virtually any of the forearms shown below, an unbalance is created in the bridge and will bring about a nonzero outcome voltage.
Figure 3: Schematic set-up of an strain gauge
c) Describe how sensitivity of such set-up can be increased, and exactly what is a possible solution to compensate for environmental temp variations.
The sensitivity of the setup shown in number 3 can be further improved by using a 50 % bridge circuit and also a full bridge circuit.
When utilizing a 50 percent bridge circuit (amount 4 still left) the sensitivity can be doubled with two gauges which are active. In this kind of create the productivity voltage is linear and the result value is double from the one shown in body 3.
Figure 4: 1 / 2 bridge (still left) & Full bridge Wheatstone circuit
By utilizing a full bridge circuit as shown in amount 4 right side side the sensitivity can be further enhanced by having all four arms productive. Two gauges can be attached in tension and the other two can be installed in compression as shown in shape 5.
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Figure 5: Diagram showing a full bridge strain gauge circuit
To compensate for environmental heat variations a possible solution is to truly have a configuration where two strain gauges in the bridge are utilized. One gauge would be the active measure and the other will be located transversely to the applied strain that can be called a dummy measure as shown in physique 6.
Figure 6: Utilizing a dummy gauge to reduce temperature influences
The heat changes would be the same on both gauges which does not affect the ratio of their amount of resistance and also does not change the voltage end result therefore the temperatures affects are small.
4) What are intelligent (smart) sensors? Give general stop schematics of typical elements that constitute such a tool.
Intelligent (smart) sensors are an extension to the original detectors. The difference between a standard sensor and smart sensor is that a normal sensor detects and directs an unprocessed sign to something which then identifies the reading whilst an intelligent sensor includes a processor to process the signal.
Figure 7: Block diagram of an intelligent sensor structure
These are systems which often consist of some analogue and digital blocks. Every stop has its own function. Through the use of these detectors data can be analysed and then corrected this means no human program is needed. For example large structures use smart sensors to control light, air conditioning conditions, entrance doors, switches etc.
Some of the functions that intelligent receptors do are self-diagnosis of faults, real-time data control, communication interface and many more.
5) Make an effort to list all the duties and requirements of your hydraulic fluids found in hydraulic installations.
Hydraulics is trusted around the world in simple applications like ability steering of an automobile and also high tech applications like in aircrafts where safety precautions are incredibly important. By utilizing a pump, other components (DCV's), actuators and a hydraulic liquid mechanical power may be accomplished like lifting and pressing. The hydraulic essential oil which is sued needs to fit the necessity needed for the procedure to take place. For different applications different kind of hydraulic fluids are utilized. In hard coal mining and forging presses lower in flammability fluid can be used due to high risk for temperatures therefore synthetic oils are used instead of standard natural oils.
Although different types of fluids are used they all need to perform the same responsibilities. These duties are: pressure transfer, lubricating the moving parts, cooling, damping (cushioning) of pressure fluctuations in the system, cover against corrosion, reduce abrasion and indication transmission.
For the hydraulic fluid to execute the tasks mentioned above the fluid will need the lowest possible density, good ageing stableness, good viscosity-pressure/ heat range characteristics and so many more, air release, non-frothing, resistance to chilly, wear and corrosion cover and water separable.
Nowadays normal water hydraulics is improving but the basic principle tasks mentioned previously still have to be done no subject the liquid used.
M3) Present and converse appropriate findings.
6) Shaft power calculation
Flow rate = 35dm3/min
Pressure rise = 100 club x 105Pa = 100MPa
Overall efficiency = 87%
To convert the movement rate from minutes to seconds:
Q = 5. 833m3/min
If we find the liquid power we can then find the shaft power:
Therefore now we will get the shaft ability:
7) For the given schematics of dual pilot run check valve locking circuit identify the numbered components and make an effort to summarize the circuit's operation.
7. 1) The different parts of circuit
Filter and check valve - (in case there is filter blockage smooth moves through the check valve)
7. 5kW electric motor
Direction of motor and pump
Constant displacement hydraulic pump with one course of movement (38 l/min)
4/3 way directional control valve, mid position closed, springtime return (both factors) and managed via solenoid with one effective coil.
Solenoid with one active coil
Pilot handled check valve
Double acting hydraulic cylinder with double ended piston rod
7. 2) Circuit procedure description
When the electric motor (2) is started the hydraulic pump (5) starts to turn. Hydraulic oil passes through the filtration before entering the hydraulic pump. When the filter is clogged the engine oil will bypass the filtration and go through the check valve (in section 1). A stream meter (4) and pressure measure (6) are installed to check the circulation and pressure of the hydraulic. Without activation of the solenoids the DCV (7) has its plug-ins open to drain that will cause the pilot lines to weather therefore close the check valves.
When both solenoids A1 and B1 are off, the DCV (7) will be in the focused position. With this position both ports are available to the tank that allows the pilot pressure to drop and the pilot handled check valves to close. Which means hydraulic cylinder is locked.
When solenoid A1 is activated the valve will move to the right and the hydraulic cylinder (11) starts to extend. What happens is pressure is build-up in the pilot series that brings about the piston end which opens the check valve (10). The other check valve starts by pump pressure like any other check valve and hydraulic starts off to stream.
When solenoid B1 (8) is triggered the valve will proceed to the still left and the hydraulic cylinder (11) begins to retract. What happens is pressure is build up in the pilot series (9) which opens the other check valve this time. Check valve (10) starts by pump pressure like any other check valve and hydraulic starts to flow.
If the DCV (7) is the center position, and it's ports are shut down then the check valves will remain open which allow cylinder creep.