Showing posts with the label Technical

List of 8 Beneficial Changes made in the Standard of Fire Pumps over the Years

Standards governing the design of fire pumps are updated every few years. This is done to ensure that these address the new design challenges and overcome the shortcomings of previous designs. In this light it would be quite interesting to look back over the last 10 years and gauge the important changes that have happened in these standards. A close analysis will reveal that the designs have significantly evolved for the better; these now ensure superior performance and safety. Here we will look back and see some of the major changes in the standard of fire pumps and their resulting benefits. 1. Torsion analysis for right angle gear drives For vertical shaft pumps that are right angle gear driven, a torsion analysis is mandatory. This helps to identify and eliminate any damaging stresses or liner resonant frequencies created from the operating speed range of the rotating equipment. This will help avoid any potential damage to the pump equipment. 2. The right diese

Recirculating Ball Screw

This type of power screw is used for high  speed high efficiency applications, and is  becoming more common. It has become  popular because it is essential in CNC, as well as robots and aircraft actuators. The ball screw assembly is as shown below and includes a circular shaped groove cut in a helix on the shaft. The ball nut also includes an internal circular shaped groove which matches the shaft groove. The nut is retained in position on the shaft by balls moving within the groove. When the nut rotates relative to the shaft the balls move in one direction along the groove supporting any axial load. When the balls reach one end of the nut they are directed back to the other end via ball guides. The balls are therefore being continuously recirculated. The recirculated ball screw has the following advantages and disadvantages to the conventional threaded power screws:  Advantages: 1.High Efficiency - Over 90% 2.Predictable life expectancy 3.Precise and repeatable mo


A clutch is a mechanical device that provides for the transmission of power (and therefore usually motion) from one component (the driving member) to another (the driven member) when engaged, but can be disengaged. Clutches are used whenever the transmission of power or motion needs to be controlled either in amount or over time (e.g., electric screwdrivers limit how much torque is transm itted through use of a clutch; clutches control whether automobiles transmit engine power to the wheels). In the simplest application, clutches are employed in devices which have two rotating shafts (drive shaft or line shaft). In these devices, one shaft is typically attached to a motor or other power unit (the driving member) while the other shaft (the driven member) provides output power for work to be done. In a torque-controlled drill, for instance, one shaft is driven by a motor and the other drives a drill chuck. The clutch connects the two shafts so that they may be locked together and s


Surface tension is a contractive tendency of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in the floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects (e.g. water striders) to run on the water surface. This property is caused by cohesion of similar molecules,  and is responsible for many of the behaviors of liquids. Surface tension has the dimension of force per unit length, or of energy per unit area. The two are equivalent—but when referring to energy per unit of area, people use the term surface energy—which is a more general term in the sense that it applies also to solids and not just liquids.The cohesive forces among liquid molecules are responsible for the phenomenon of surface tension. In the bulk of the liquid, each molecule is pulled equally in every direction by neighboring liquid molecules, resulting in a net force of zero.

Mechanical Quotations

Here are some cool mechanical engineering t shirt quotes for you to write on your mechanical engineering class t shirt. Please share with us more mechanical engineering t shirt quotes in comments to this post. Gentlemen I will Start your Engines Suck-Squeeze-Suck-Squeeze We do it 4 stroke way I Screw for a Living Ask Me for a Lube job Have you checked your oil lately Let me tighten your bolts ! We do it Four Stroke way Let me check your Horn Rear End Collision Specialist Ask me about my Toolbox ! Got the Nerve to dare ME? Inspiration is only beginning rest is all about being ME! Nut is as per bolt Highly Mechanized Mechanical Engineering, a shear delight Get in gear with a mechanical engineer I am not a nut but i can screw well I believe in the big bang theory I am not a mechanic but a mechanical engineer Never take ME as granted! Do you have more witty and funky mechanical engineering t shirt quotes or slogans? Please share with us by commenting on this post. Want

Six Stroke Engine

The six-stroke engine is a type of internal combustion engine based on the four-stroke engine, but with additional complexity intended to make it more efficient and reduce emissions. Two different types of six-stroke engine have been developed since the 1990s: In the first approach, the engine captures the heat lost from the four-stroke Otto cycle or Diesel cycle and uses it to power an additional power and exhaust stroke of the piston in the same cylinder. Designs use either steam or air as the working fluid for the additional power stroke.[1] The pistons in this type of six-stroke engine go up and down three times for each injection of fuel. There are two power strokes: one with fuel, the other with steam or air. The currently notable designs in this class are the Crower six-stroke engine, invented by Bruce Crower of the U.S. ; the Bajulaz engine by the Bajulaz S.A. company of Switzerland; and the Velozeta Six-stroke engine built by the College of Engineering, at Trivandrum in Ind

Solar-powered refrigerator

Solar-powered refrigerators are most commonly used in the developing world to help mitigate poverty and climate change. By harnessing solar energy, these refrigerators are able to keep perishable goods such as meat and dairy cool in hot climates, and are used to keep much needed vaccines at their appropriate temperature to avoid spoilage.  The portable devices can be constructed with simple components and are perfect for areas of the developing world where electricity is unreliable or non-existent. [1] Other solar-powered refrigerators were already being employed in areas of Africa which vary in size and technology, as well as their impacts on the environment.  The biggest design challenge is the intermittency of sunshine (only several hours per day) and the unreliability (sometimes cloudy for days). Either batteries (electric refrigerators) or phase-change material is added to provide constant refrigeration.

Tubeless tires

   Tubeless tires are pneumatic tires that do not require a separate inner tube. Unlike traditional pneumatic tires which use a separate inner tube, tubeless tires have continuous ribs molded integrally into the bead of the tire so that they are forced by the pressure of the air inside the tire to seal with the flanges of the metal rim of the wheel. Traditional designs of pneumatic tires required a separate inner tube which could fail for a number of reasons, such as incorrect tire fit, friction between the tire wall and inner tube generating excess heat or puncture. Tubeless tire technology does away with the need for an inner tube thereby increasing safety. In a tubeless tire, the tire and the rim of the wheel form an airtight seal, with the valve being directly mounted on the rim. If a tubeless tire gets a small puncture, air escapes only through the hole, leading to a gentle deflation. Conversely, an inner tube could potentially burst like a balloon, leading to a rapid deflatio

Thermal energy

T hermal energy is generated and measured by heat of any kind is due to the increased activity or the speed of molecules in a substance, which in turn causes temperature causes rise accordingly. There are many natural sources of thermal energy on the earth, making it an important component of alternative energies. To explain the laws of thermodynamics, that energy can be exchanged to another in the form of heat from a physical object. For example, putting fire under a pot with water, the water is heating up as a result of the increased molecular motion. In this way, the heat or thermal energy, the fire is partially transferred to the water. Understanding the principles of thermodynamics has allowed people to use to create the natural sources of heat, thermal energy from a variety of sources. The sun, ocean and geothermal sources such as geysers and volcanoes, all sources of thermal energy. As an exhausted people, sustainable forms of alternative energy instead of fossil resources, such

Hybrid vehicle

Many people have probably owned a hybrid vehicle at some point. For example, a  mo-ped  (a motorized pedal bike) is a type of hybrid because it combines the power of a  gasoline engine  with the pedal power of its rider. In fact, hybrid vehicles are all around us. Most of the  locomotives we see pulling trains are  diesel-electric hybrids . Cities like Seattle have diesel-electric  buses  -- these can draw electric power from overhead wires or run on diesel when they are away from the wires. Giant  mining trucks  are often diesel-electric hybrids.  Submarines  are also hybrid vehicles -- some are  nuclear-electric  and some are  diesel-electric . Any vehicle that combines two or more sources of power that can directly or indirectly provide propulsion power is a hybrid. Most hybrid cars on the road right now are gasoline-electric hybrids, although French car maker PSA Peugeot Citroen has two diesel-electric hybrid cars in the works. Since gasoline hybrids are the kind you'll find at

Technical files

*presentations and documents for the Mechanical* 3d_machine_vision_systems   [DOC] a_web_based_manufacturing_service_system_for_rapid_product_development  [PPT] adaptive_control_system   [DOC] air_brake_system   [DOC] air-muscle   [DOC] automatic_speed_control_system   [DOC] bending_load_capacity_enhancement_using_asymmetric_tooth_profile   [PPT] composites_materials [ DOC] di_diesel_engine   [DOC] emulsified_ethanol   [DOC] fuel_cells   [DOC] liquid_nitrogen   [DOC] mechanical_design   [PPT] mechanical_properties_i   [PPT mechanical-working-of-metals   [PPT] mechanics_of_metal_cutting   [PPT] metallurgical_changes_in_steels_   [DOC] microelectromechanical_systems   [DOC] nanotechnology_and_prototyping   [DOC] nanotechnology_new   [DOC] nanotechnology_perfecting_the_future   [DOC] nd_evaluation_of_composite_pressure_vessels_using_fbg_sensors [PPT] neural_networks   [DOC] six_sigma [ DOC] tidal_power   [DOC] vehicle_dynamics   [DOC] 

Power Plant Engineering

Power Plant Engineering 1. Name the four major circuits in steam power plant. ·          Coal and ash circuit ·          Air and flue gas circuit ·          Feed water and steam circuit ·          Cooling water circuit 2. What consists of air and flue gas circuit?             Air and flue gas circuit consists of forced draught fan, air‑pre‑heater, boiler, furnace, super heater, economiser, dust collector, induced draught fan and chimney. 3. What consists of feed water and steam flow circuit in steam power? The feed water and steam flow circuit consists of feed pump, economiser boiler drum super heater, turbine and condenser. 4. What consists of cooling water circuit and coal & ash circuit in steam power plant?             The cooling water circuit consists of a pump, condenser and cooling tower. The coal and ash circuit consists of coal delivery, preparation of coal, handling of coal to the boiler furnace, ash handling and ash storage. 5. What is the main purpose of the r