COMPARATIVE STUDY OF RAILWAY TRACK INSPECTION …
This project models track inspection operations on a railroad network and discusses how the inspection results can be used to measure the risk of failure on the tracks. In particular, the inspection times of the tracks, inspection frequency of the tracks, and times between consecutive inspections on the same tracks should be considered for scheduling inspections on the railroad tracks.
Furthermore, an inspection plan should schedule inspections considering the characteristics of different tracks.Therefore, it is important to schedule track inspections such that the potential defects are captured as much as possible within minimum times to increase safety. The project formulates a required, time between consecutive inspections, and importance of distinct tracks.
The two objectives simultaneously captured in this model are minimization of total inspection times and maximization of the weighted inspections. An efficient solution method is proposed for solving this model.
The solution method is compared to a scheduling procedure, which can be used in absence of the findings in this project, on a set of railroad track networks of different sizes. Based on the comparison, the solution method proposed proves to find improved inspection schedules regardless of the railroad network size. A review of the techniques on how to use the inspection results to measure risk of failure is provided.
The main objective for taking this project is to provide the requirements, processes and guidelines for the inspection of track and for the response of track defects. It includes all inspections undertaken during track examination, track recording & special inspections.
This project is part of Mechanical Engineering suite that comprises standards , installtion, maintenace & specifications.
To arrange the ongoing safety of the track and to effectively manage the repair of condition and replacement of components.
Sequence Of Operations Involved In The Project….
1.By the end of September we will go through all the legal documents of INDIAN RAILWAY related to the railway tracks with the help of DRM headquater CENTRAL RAILWAY, NAGPUR.
2.After going through all the documents we will analyse about the problems that currnetly occuring very frequently in our system.
3.After analysing the problem we will try to find the permanent solution to the problem.
4.Our main aim in the project is to reduce the track inspection frequencies without affecting the risk of accidents and failures of track
Existing Railway Track Technology in INDIA…
The central railroad administration provides data on railroad accidents throughout the India. According to this database, between 2006 and 2016, 78 train accidents occurred in India.
Of these accidents, 17 occurred due to the track geometry, 11 due to the defects in track components, such as rail, fasteners, and joints, and 9 due to defects in switches. Faulty tracks account for more than one-third of all railroad accidents.
Maintenance of the expanding network of rail tracks requires a sizable investment of time and effort. According to the Indian Railway Administration‟s Office of Safety Analysis, from 2005 to 2015, 45,842 inspections were performed nation-wide and 216,100 defects were recorded. Nonetheless, despite the high level of inspection effort involved, the continuing high accident rate raises questions about the
extent to which the railroads comply with the inspection requirements as well as about the extent to which inspections can help to avert accidents. Great levels of performance can be achieved through the automation of inspection using computer vision systems, as they allow scalable, quick, and cost-effective solutions to tasks otherwise unsuited to humans.
Track and gauge……
Indian railways uses four gauges, the 1,676 mm (5 ft 6 in) broad gauge which is wider than the 1,435 mm (4 ft 8 1⁄2 in) standard gauge; the 1,000 mm (3 ft 3 3⁄8 in) metre gauge; and two narrow gauges, 762 mm (2 ft 6 in) and 610 mm (2 ft).
Track sections are rated for speeds ranging from 80 to 200 km/h (50 to 124 mph).Though trains don’t really clock speeds of 200 km/h.
The total length of track used by Indian Railways is about 115,000 km (71,000 mi) while the total route length of the network is 67,312 km (41,826 mi).About 27,999 km (17,398 mi) or 42% of the route-kilometre was electrified, as of 31 March 2016.
Broad gauge is the predominant gauge used by Indian Railways. Indian broad gauge—1,676 mm (5 ft 6 in)—is the most widely used gauge in India with 108,500 km (67,400 mi) of track length (94% of entire track length of all the gauges) and 59,400 km (36,900 mi) of route-kilometre (91% of entire route-kilometre of all the gauges).
In some regions with less traffic, the metre gauge (1,000 mm (3 ft 3 3⁄8 in)) is common, although the Unigauge project is in progress to convert all tracks to broad gauge. The metre gauge has about 5,000 km (3,100 mi) of track length (4% of entire track length of all the gauges) and 4,100 km (2,500 mi) of route-kilometre (7% of entire route-kilometre of all the gauges).
The Narrow gauges are present on a few routes, lying in hilly terrains and in some erstwhile private railways (on cost considerations), which are usually difficult to convert to broad gauge. Narrow gauges have 1,500 route-kilometre. The Kalka-Shimla Railway, the Kangra Valley Railway and the Darjeeling Himalayan Railway are three notable hill lines that use narrow gauge, but the Nilgiri Mountain Railway is a metre gauge track. These four rail lines will not be converted under the Unigauge project.
The share of broad gauge in the total route-kilometre has been steadily rising, increasing from 47% (25,258 route-km) in 1951 to 86% in 2012 whereas the share of metre gauge has declined from 45% (24,185 route-km) to 10% in the same period and the share of narrow gauges has decreased from 8% to 3%. About 27,999 route-km of Indian railways is electrified.
Sleepers (ties) are made up of prestressed concrete, or steel or cast iron posts, though teak sleepers are still in use on a few older lines. The prestressed concrete sleeper is in wide use today. Metal sleepers were extensively used before the advent of concrete sleepers.
A railroad is built from several basic components. Two steel rails are mounted in parallel, which supports the efficient motion of the rail cars. These rails are laid upon crossties, either wooden or concrete, which are embedded in ballast and laid perpendicular to the rails. Corssties span a distance greater than the width between the rails.
The tracks are supported by a flexible bed of ballast which might be a mixture of gravel and/or aggregate. Finally, the rails are anchored by fasteners or clips to the concrete crossties, and by tie plates to wooden crossties. The fasteners and plates can take many forms .
Steel spikes hold tie plates in place in wooden crossties, while steel bolts are used to hold fasteners in concrete crossties. Rails typically have a length of about 60 feet. Rails joints are where the two rails meet. Rails can be welded or unwelded at rail joints. Most railways in the USA built after 1950 use continuously welded rails.
In these tracks, rails are welded together by using flash butt welding to form a single rail which can be thousands feet long. If rails are unwelded, they are held together by joints, bars, and bolts. Basic track geometry parameters include gauge (roughly speaking, the distance between the rails) and cross-level (the difference in height of the rails). Curvature (the difference in heading of two locations 100 feet apart expressed in degrees) is another important track geometry parameter.
Two additional parameters are alignment and profile. Railroad tracks are laid out according to a mathematical model. Three types, interconnected to define a desired path, comprise the track. These types are referred to as tangent, spiral, and curve. Tangent segments are straight or linear, curved segments have a fixed radius, and spiral segments interconnect tangent and curve sections.
The most commonly used grade for rail steel is 880 grade which is fully pearlitic microstructure (EUTECTOID STEEL). 880 represents the ultimate tensile strength which is 880Mpa( appx).
The nominal composition in weight% for 880 grade
1.Carbon- 0.6-0.8 2.Manganese-0.8-1.13
7.Hydrogen-<3ppm(parts per million)