CHOKE IN BIKES

Choke valve in bikes :-

A choke valve is sometimes installed in the carburetor of internal combustion engines. Its purpose is to restrict the flow of air, thereby enriching the fuel-air mixture while starting the engine. Depending on engine design and application, the valve can be activated manually by the operator of the engine (via a lever or pull handle) or automatically by a temperature-sensitive mechanism called an autochoke.

Why it is important?

Choke valves are important for naturally aspirated gasoline engines because small droplets of gasoline do not evaporate well within a cold engine. By restricting the flow of air into the throat of the carburetor, the choke valve reduces the pressure inside the throat, which causes a proportionally greater amount of fuel to be pushed from the main jet into the combustion chamber during cold-running operation. Once the engine is warm (from combustion), opening the choke valve restores the carburetor to normal operation, supplying fuel and air in the correct stoichiometric ratio for clean, efficient combustion.

A 9,000-Pound Tank That’s Faster Than a Ferrari

A 9,000-Pound Tank That’s Faster Than a Ferrari :-

After drones took over the skies, Ripsaw is now taking control over land. Ripsaw is the world’s fastest tracked vehicle produced by Howe & Howe Technologies in Maine. Unlike other unmanned ground vehicles (UGV), which are slow, Ripsaw can accelerate to 65 mph in about 3 seconds. By comparison, the Ferrari F12 Berlinetta can accelerate to 62 mph in 3.1 seconds.

Ripsaw, made from tough alloy steel, is very quick and agile and could be used for perimeter defense, surveillance, rescue, border patrol, crowd control and explosive ordnance disposal roles. 

RESISTANCE SPOT WELDING

Resistance Spot Welding:

In spot welding the weld is effected by the heat produced due to resistance to the flow of current through two or more overlapping work pieces held pressed together between the electrodes. This is the simplest form of resistance welding and does not pose any problem for welding sheets ranging u to 12.5 mm in thickness. The majority of spot welding is however done with metal pieces less than 6 mm thick.

HONING

Honing:-

Honing or to "Hone"is an abrasive machining process that produces a precision surface on a metal workpiece by scrubbing an abrasive stone against it along a controlled path. Honing is primarily used to improve the geometric form of a surface, but may also improve the surface texture.

Typical applications are the finishing of cylinders for internal combustion engines, air bearing spindles and gears. There are many types of hones but all consist of one or more abrasive stones that are held under pressure against the surface they are working on.

COMPUTATIONAL FLUID DYNAMICS (CFD)

Computational fluid dynamics:-

Computational fluid dynamics, usually abbreviated as CFD, is a branch of fluid mechanics that uses numerical analysis and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with surfaces defined by boundary conditions. With high-speed supercomputers, better solutions can be achieved. Ongoing research yields software that improves the accuracy and speed of complex simulation scenarios such as transonic or turbulent flows. Initial experimental validation of such software is performed using a wind tunnel with the final validation coming in full-scale testing, e.g. flight tests.

DIFFERENCE BETWEEN IMPULSE AND REACTION TURBINE

Difference Between Impulse And Reaction Turbine. 

HOW BRAKES STOP VEHICLES

HOW BRAKES STOP VEHICLES:-

Brakes are an energy-absorbing mechanism that converts vehicle movement into heat while stopping the rotation of the wheels.

All braking systems are designed to reduce the speed and stop a moving vehicle and to keep it from moving if the vehicle is stationary.

Service brakes are the main driver-operated brakes of the vehicle, and are also called base brakes or foundation brakes.

Most vehicles built since the late 1920s use a brake on each wheel. To stop a wheel, the driver exerts a force on a brake pedal. Force on the brake pedal pressurizes brake fluid in a master cylinder.

This hydraulic force (liquid under pressure) is transferred through steel lines and flexible brake lines to a wheel cylinder or caliper at each wheel. Hydraulic pressure to each wheel cylinder or caliper is used to force friction materials against the brake drum or rotor.

The heavier the vehicle and the higher the speed, the more heat the brakes have to be able to absorb.Long, steep hills can cause the brakes to overheat, reducing the friction necessary to slow and stop a vehicle

FRICTION WELDING

Friction welding:-

Friction welding (FRW) is a solid-state welding process that generates heat through mechanical friction between workpieces in relative motion to one another, with the addition of a lateral force called "upset" to plastically displace and fuse the materials. Technically, because no melt occurs, friction welding is not actually a welding process in the traditional sense, but a forging technique.

TYPES OF BELT DRIVES

Types of Belt Drives:-

Belt drives are widely used in many industries for power transmission since they are cheap and easy to maintain.

The most common types of belt drives include:

Round belts:-
Round belts are are generally made of rubber. This type of belt is generally used for light loads, such as in a sewing machine or a vacuum cleaner.

V belts:-
V belts are arguably the most widely used belts in industry. V belts have a V shaped cross-section, which rests against the side of V pulley under tension. The V shaped cross-section prevents belt from slipping off.

Flat belts:-
Flat belts are also used to transmit power from one shaft to another. They are generally classified as either small woven endless belts or higher power flat belts. The woven endless belts are especially useful where minimum vibration is required at the driven pulley due to semi-elastic material used in construction. The higher power flat belts are often useful because they eliminate the need to high belt tension used to grip pulleys, which in turn reduces the load on the shaft bearings. The material used for high power flat belts is sticky yet abrasion-resistant rubber compounds.

Timing/toothed belts:-
Timing belts are toothed belts that use their teeth for power transmission, as opposed to friction. This configuration results in no slippage, and therefore, the driving and driven shafts remain synchronized. It’s more expensive to manufacture due to complexity of the belt and pulley shapes.