Challenges In Coal Handling Operations And Locomotive Performance

Demonstrate how you propose to move the coal without interfering with current operations?

How many of each locomotive would you need to run the train?

What would the speed be at the end of the ruling gradient for each locomotive consist?

What is the required adhesion to start the train on the ruling gradient for each locomotive consist and advise whether this is reasonable?

When you consider the electric locomotive performance, a further variable you will need to advise on is whether the electric locomotive available to you is a viable option.

What factors other than the performance will you need to consider? The line is not currently electrified.

Evaluate whether the reliability of Dynamic Brake is the critical factor in the safety of braking heavy freight trains on long gradients?

Would your conclusions be different if the dynamic brake was capable of 700 kN per locomotive from 5 to 30km/hr and 300 kN at 80km/hr?

Locomotive Performance 1

Over the past decades, coal handling has continued to pose different challenges worldwide. However, the overall process regarding the operations and processing of coal is following aspects which need to be considered. Various issues and problems are associated with the exploration and transportation of the coal minerals from the site to the industry and such challenges include water and air pollutions. The challenges impacts directly to both the operator and the user of the product in the long run and some of the key proposals for handling the overall coal without interference include training the operator on the various handling techniques which minimize existing operations.  Therefore, design characteristics, as well as transportation considerations, are employed to ensure that the all the transportation of the coal from the site of exploration to the industry is not interfered with in the long run (Wang et al. 2011).  

Locomotive Performance 1

3500kW Diesel Electric Locomotive

3333 kW for traction diesel electric

 Starting TE = 800 kN Continuous

TE = 600 kN at 20 km/hr

Mass = 180 tonnes

Gauge= 1435 mm

Fuel Tank Capacity= 9000 litres

Area = 12m2

No of Axles = 6

But from the Davis Equation in line with the locomotives,

Locomotive Resistance, R= 

Locomotive Resistance of 1

= 5531.388

= 907.725kN

Thus,

  = 907.725Kn

Locomotive 2 Performance

2300 kW for traction diesel electric

2500 kW Total.

Starting TE = 500 kN

 Continuous TE =375 kN at 20 km/hr

Mass = 138 tonnes

Gauge= 1435 mm

Fuel Tank Capacity= 6000 litres

 Area = 12m2

 No of Axles = 6

Locomotive Resistance of 2

= 4442.64k N

Locomotive 3 Performance

6500 kW Electric Locomotive

6400 kW for traction

Starting TE = 570 kN

1HR TE = 450kN at reduced power

Continuous TE =325 kN at 70 km/hr

Continuous TE = 325 at reduced power

Mass = 130 tonnes

 Gauge= 1435 mm

 Electrical Overhead Power 25 kV AC

Area = 12m2

No of Axles = 6

Locomotive Resistance of 3

= 4245.408

	TE (kN)	Train Resistance (kN)	Number locomotives
Locomotive 1	600	907.725	1.5
Locomotive 2	375	907.725	2.4
Locomotive 3	325	907.725	2.793

Locomotive 1 Mass = 1.5 x 180 = 270N

  = 33.075kN

Locomotive 2 Mass = 2.4 x 138 = 331.2N

  = 40.572kN

Locomotive 3 Mass = 2.793 x 130 = 363.09N

  = 44.479kN

According to Wang et al. (2011), the number of locomotives which are required to operate the train mainly depicted to be six and this is based on the standard regulations which are set and adhered worldwide in line with the train operations in the coal mine. The amount required in gearing the locomotive mainly in most instance relies on the engine loads and various factors often pull this. Some of the elements depicted in locomotive include its own power to draw 0.56km per litre. Also, it is evident that for every 5000 tons of loco it will consume approximately 4litres per kilometer (Wang et al. 2011). 

Locomotive Performance 2

Different topography and locations require different ruling gradients as far as the locomotive aspect is concerned. Thus, the speed which the train will be moving with as per the analysis is about 90km per hour and this is taken in line with the operational procedures and standards.

Would you recommend increasing the length of the train for any of the locomotive types, explain the reasons for your recommendation?

I would recommend retaining the current length rather than increasing it except for the freight train. In the case of the freight train, I will support raising the overall length. This is because increasing it to about four times will ensure that the power is distributed makes it possible to perform and operate in the advent. Furthermore, increasing the length also will help in providing that the freight long chains in the engine section function correctly. Notably, the power in the cargo due to the increased length will ensure that the freight train can operate regarding longer and heavier loads without necessarily increasing the overall derailing risks in the stem. Thus, reducing the makeable stresses associated with pulling the various long train car chains across decisive curves (Wang et al. 2011). 

Mainly defined as the ability of the train to brake safely as well as have the overall massive haul and this term has a broader and fundamental application in trains. Furthermore, it helps in limiting both the braking effort as well as the tractive effort per traction in the subway. Also, the figure below shows the analysis of the adhesion required in line with the locomotive train.

Preferably, it is noted that the maximum start adhesion required where micro-slips is involved about 0.73 and this condition is only attained when the steel to steel elements are used. Furthermore, the condition requires that maximum value obtained is convertible to the adhesion weight in the long run. Thus, the situation sounds ideal but cannot be attained in the actuality because the prevailing conditions fluctuate on a daily basis (Teimourimanesh, Vernersson, and Lundén, 2016).

First and foremost, it is important to note that electrical locomotive is driven and powered by the overhand electrical cables and lines. An electric locomotive is often a viable option because the systems benefit from the overall high electric efficiency motors of about 90%. Also, the electric locomotives often have a regenerative braking technique which allows them to recover the overall kinetic energy more so during the braking and this helps them in putting the power back to the systematic lines. Moreover, adopting the latest and newer AC motor-inverters will assist in the provision of the regenerative braking more efficiently. Furthermore, it is convenient to use the electrical trains since they have fewer elements and disruptions more so the noise as compared to the others such as the diesel trains. Electric trains also do have replication in terms of the parts and thus, helps in reducing the existing track maintenance (Wang et al. 2011).  Electric trains have the capacity of producing higher power output as compared to the locomotive diesel and this hastens the short-term surge and thereby making them accelerate faster. They are being used as the commuter rails where frequent stops services are required. Furthermore, they can be used in high traffic volumes as well as in advanced regions in line with the rail networks. The power plants associated with them are often clear than any other available locomotive engine sources. Furthermore, the driving power to be used in the technique can be derived from the renewable sources such as hydroelectric power, solar power, geothermal as well as wind turbines.

Locomotive Performance 3

There are different factors rather than just the performances which need to be considered when introducing the electric train and these factors include a power supply, the shoes alongside shoe-gears, gap as well as the return current. These parameters are mainly discussed as follows

Power Supply

 It is fundamental and the key to appraising the all related issues in line with the power supply for the electric train. The train mainly powered by two principal power sources which include the direct as well as indirect current. The power applied in the train must meet three criteria which include economic viability, user-friendly as well as environmental sustainability. Thus, the analysis of the power supply mainly depicted as per the below figure (Teimourimanesh, Vernersson, and Lundén, 2016).

The figure showing power supply in the electric locomotive

Gap

It is another fundamental element which must be evaluated and appraised when introducing the electric train. Often one can only depict one pantograph in the train as far as the use shoes in the trains are concerned.  However, these elements are numerous in the electric train and must be taken into consideration when designing and coming out with the electric train adoption system. The gap in the train is mainly defined as the third broken rail elements which are often evident at the various junctions and their leading role are to assist in enhancing running continuity rails. This helps in reducing the associated power losses as far as the train is concerned. The analysis on the gap mainly summarized as shown in the diagram below (Teimourimanesh, Vernersson, and Lundén, 2016)

Shoes as well as Shoe-gear

It is also an essential factor which must be considered when introducing the electric and it helps in depicting designs contacts of the train system as shown in the diagram below

7. Given the proposed performance what would be the speed you would expect on the ruling gradient.

The expected speed based on the proposed performance in line with the ruling gradient mainly estimated at TE = 600 kN at 20 km/hr ((Teimourimanesh, Vernersson, and Lundén, 2016).

Locomotive 1 has an availability of 90%, locomotive 2 85% and locomotive 3 has an availability of 95%. How many locomotives will you need for the total transport task?

The total number of locomotives which will be required for the transport system mainly depicted to be six.  That is locomotive-1 will require one locomotive. On the hand, locomotive 2 and locomotive 3 will produce two and three locomotives respectively. In essence, it is important to note that the selections essentially are taken with considerations that all engines have efficiencies of at least 85% in line with system operations in the long run.

Increasing Length of Trains

Part B - Brake Power and Thermal Damage

 =  = 102.3kN

Dynamic brakes from the graph = 140kN

• Locomotive-a dynamic speed = 50km/hr
• Locomotive-b dynamic speed = 60km/hr
• Locomotive-c dynamic speed = 70km/hr
• Locomotive-d dynamic speed = 80km/hr

Review the accident investigation report Derailment of Union Pacific Railroad Unit Freight Train 6205 West Near Kelso, California. January 12, 1997 (National Transportation Safety Board 1997), and estimate the maximum recommended speed for safety. (Note that approximately 22kW (30 hp) of brake power per wheel is considered the peak for protection due to block fade and wheel damage).

Following the various accidents which emerged in California State, an inspection was carried out and various recommendations were estimated in order to curb the multiple issues related to the locomotive accidents in the country in line with the speed. First and foremost, a suggestion was given on the attainable speed which the train the train must operate when in the descending along the Kelso and the Cima. It is essential to maintain a speed limit of about 5 mph. in fact, the analysis shows that at a specified steep-grade of 23 along the Kelso and Cima it is advisable to the train if the speed of about 5 mph is exceeded in the process. The railroad thus should be stopped by pressing the emergency brake in the locomotive. Furthermore, it is essential to use the full-service braking application in the train o stop if the speed exceeds 5 mph. in the braking process also, it advisable to apply hand brakes to minimize the movements and do not start the train unless directed by the instructor.

From the analysis, there is an established rule which states that whenever a train exceeds the set speed by the about 5 mph, then the technician or the engineer must stop the locomotive train immediately. This is taken with reference to the maximum speed under which the locomotive tends to operate. The engine must be stopped in order to allow the operating to troubleshoot the problem in the train. This designed analysis aims at equipping the operating engineer with vast knowledge and understanding of the railroad events and information. The adoption of this policy has enabled railroads to be successful in terms of the operation and safety and thus, have prevented runaways.

 Review the article Wheel Thermal Damage Limits (Stone & Carpenter 1994), and consider whether you would recommend raising the train speed to track speed.

This article gives an overall view on the various elements in line with the thermal damages and limits and this case; it is established that the total thermal limit damages rely on the train speed alongside track speed. Whenever the train speed is increased in line with the mechanical system, then the load transmitted in the system also increases imminently. Moreover, increasing the makeable train speed leads to the rising in the vertical stress dynamic and as a result vertical quasi-static strain values and the locomotive loading doubles.  Thus, I would recommend raising the overall train speed as well as track speed when heavy loads are being used in the system so as to hasten the transportation and movement of such elements and items (Teimourimanesh, Vernersson, and Lundén, 2016).

Adhesion and Braking Techniques

What would you need to investigate and what should possibly be improved before you made the recommendation.

There are various elements and factors which must be examined and evaluated before coming up with different recommendations regarding the thermal limits and barking system in the train. Alt the parameters assessed and appraised in the process are exceedingly important to the system in terms of the wheels dimensioning in line with the railway. Some of the critical elements examined and considered before establishing the various recommendations mainly include temperature gradient, residual stresses and braking blocks of the material used. These elements primarily explored and compared via the wheel disc and wheel rim. Furthermore, considerations and viable evaluation also conducted for the overall heating partitioning in the system. In essence, the partition essentially examined between the brake block, wheel, as well as rail and the results, compared with ones obtained from the braking cycle temperature difference in the long run (Teimourimanesh, Vernersson, and Lundén, 2016).

Often, the traction motors situated in the locomotive axle mainly utilized in starting and operating the train as it moves along the track. In fact, the system used and helps by providing power to hasten the wheelsets operations. Moreover, the existing mechanical strength obtained as a result of moving the wheelsets helps in slowing the process when the power is being converted to electrical energy. On the other hand, traction motors can also help and act as the overall generators. In this case, they will help to hasten the wheelsets so as to generate power and this will assist in reducing the train speed. This process is what is defined as the dynamic braking in trains. Moreover, the overall generated current can then be directed to the resistors banks from where they will dissipate heat. Also, the generated heat can also be stored in the power supply of the railway and thus termed as regenerative braking. Therefore, it is evident that dynamic braking is not only a key factor but also an essential element to be considered as far as the braking and the safety of the heavy freight trains is concerned (Teimourimanesh, Vernersson, and Lundén, 2016).

Once, the dynamic brake system has been set at a certain distance and the speed, then even if the overall system parameter is changed within the limit, then the dynamic braking distance will remain. Therefore, it is important to note that the even if the overall dynamic braking system which had a capacity of accommodating the 700 kN per locomotive in line with 5 and 30km/hr changed. Still, the dynamic braking system for the train will remain the same as far as the set that is 300 kN at 80km/hr lies within the range (Teimourimanesh, Vernersson, and Lundén, 2016).

References

Teimourimanesh, S., Vernersson, T. and Lundén, R., 2016. Thermal capacity of tread-braked railway wheels. Part 1: Modelling. Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 230(3), pp.784-797.

Wang, W.J., Zhang, H.F., Wang, H.Y., Liu, Q.Y. and Zhu, M.H., 2011. Study on the adhesion behavior of wheel/rail under oil, water and sanding conditions. Wear, 271(9-10), pp.2693-2698.