This set of Railway Engineering written test Questions & Answers focuses on “Number, Angle of Crossing and Reconditioning of Worn Out Crossings”.
1. Which formula is used for the calculation of number of crossing based on Centre line method?
a) 2N = cot (α/2)
b) N = cot (α/2)
c) 2N = tan (α/2)
d) N = tan (α/2)
Explanation: In centre line method, number of crossings N is measured along the centre line of the crossing. N can be calculated by 2N = cot (α/2). This method is used in USA and Britain.
2. What is another name of Coles method?
a) Isosceles method
b) Right angle method
c) Centre line method
d) Back toe method
Explanation: Coles method is also known as Right angle method. It is used on Indian Railways and N is measured along the base of a Right angled triangle. N = cot (α) is the formula used.
3. All the methods used for determining the number of crossing give the same value.
Explanation: A crossing is designated either by number of crossing or by the angle the gauge faces make with each other. All the three methods used to find N give different value according to the method adopted.
4. What is the limiting wear for a crossing?
Explanation: Limiting wear for crossing is 10mm and then it needs to be replaced. When the wear is around 6mm, reconditioning of the worn out sleeper is done.
5. What is done for reconditioning of crossings at site?
a) They are hammered
b) Gas welding
c) Replacing the elements
d) Filling of material in gaps
Explanation: In case of tongue rail the limit of vertical wear for 52kg and 90R rails is 6mm. For lateral wear it is 8mm. Usually gas welding is adopted to recondition crossings at site.
6. Which of the following is used for gas welding of crossings?
a) Oxyacetylene flame
b) Methylene flame
c) Nitrogen-carbon dioxide flame
d) Ozone flame
Explanation: Firstly the surface to be welded is marked, cleaned and burns are removed. Then using oxyacetylene flame and welding rods welding is done after pre heating the surface for 5 minutes.
Sanfoundry Global Education & Learning Series – Railway Engineering.
To practice all written questions on Railway Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.