1.What is the need of high compression ratio? Today every machine is expected to give higher efficiency. When we talk about petrol engine and diesel engine whose thermal efficiency is directly related to ‘compression ratio’. That means if we want to achieve higher thermal performance in terms of efficiency, we should provide high compression ratio…
1. What causes white smoke in two stroke locomotive engines? That is the engine running too lean (lack of fuel). This condition will lead to overheating and failure of the engine. 2. What is the role of nitrogen in welding? Nitrogen is used to prevent porosity in the welding member by preventing oxygen and air…
1. How pipe flanges are electrically insulated? Pipe flanges are protected from corrosion by means of electrolysis, with dielectric flanges. The piping system is electrically insulated by what is called a sacrificial anode. A bag of readily corrodible metal is buried in the ground with a wire running from the pipe to the bag so…
1. What is annealing? It is a process of heating a material above the re-crystallization temperature and cooling after a specific time interval. This increases the hardness and strength if the material. 2. What is ductile-brittle transition temperature? It is the temperature below which the tendency of a material to fracture increases rather than forming….
1. Explain the second law of thermodynamics. The entropy of the universe increases over time and moves towards a maximum value. 2. What kinds of pipes are used for steam lines? Normally galvanized pipes are not used for steam. Mild steel with screwed or welded fittings are the norm. Pressure and temperature are very important…
1.Why gas containers are mostly in a cylindrical shape? The ideal shape would be a sphere. The container must have the capacity to withstand the extremely high pressure of liquefied gas. A spherical shape helps in distributing these forces uniformly. 2.Explain why re-heater is used in gas turbine The advantage of reheater is that it…
1.Explain what is torque Torque is the force that causes rotation. It is a measure of how much force is acting on an object making it rotate. 2.What is the difference between torque and power? While power determines the speed of a vehicle, torque determines the time in which that speed can be reached. The…
1.What is a process flow diagram? A Process Flow Diagram is a user friendly, simplified sketch which illustrates general plant streams, major equipments and key central loops and shows the relationship between major components in the system. By using symbols to identify instruments and vessels it describes the primary flow course. They also provide e…
1. What kind of materials should be used for shafts manufacturing? Some of the qualities that should be present in materials for shafts are as follows: > The material should have a high index of strength. > Also it should have a high level of machinability. > The material should possess a low notch sensitivity…
1. In order to derive the torsional formulas what are the assumptions taken? The torsion equation is derived on the basis of following assumptions: > The shaft material is uniform, throughout the shaft. > Even after loading the shaft circular remains circular. > After the application of torques the plain section of a shaft remains…