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Public Service Commission (लोक सेवा आयोग)

The Public Service Commission (Nepali: लोक सेवा आयोग) of Nepal was established on 15 June 1951. It is the main constitutional body involved in selecting meritorious candidates required by Government of Nepal for Civil Service Vacancy.[1] It is regarded as one of the most credible modes of recruitment by Nepalese. The Constitution of Nepal has regarded the

commission as an independent constitutional body. Organization Setup
The Public Service Commission is overseen by the Office of the Prime Minister and Council of Ministers. As per Part 23 of the Constitution of Nepal (2072), the PSC consists of an acting Chairman and several further members. These are selected by the President of Nepal on the recommendation of the constitutional council. 50% of the members of this are appointed from the civil servants who have served for 20 or more than so in the field of the government sector.[citation needed]

As of 2021, the chairman of the PSC was Madhav Prasad Regmi, who was nominated for the post in 2021. Reports
The PSC annually submits a report of its work to the President of Nepal. Further it is sent to legislative parliament for discussion. The commission submits an annual report on the work done by it to the president. The president places the report of the commission before the legislative parliament along with a memorandum with regard to the cases where the advice of the commission was not accepted and the reasons for such non-acceptance.

Compressor types on the basis of its displacemen
15/12/2024

Compressor types on the basis of its displacemen

⚙️ Alternator Explained: How It Works, Key Benefits, and Why Your Car Needs It:An alternator is a critical component of ...
18/11/2024

⚙️ Alternator Explained: How It Works, Key Benefits, and Why Your Car Needs It:

An alternator is a critical component of a car's electrical system that converts mechanical energy into electrical energy. It supplies power to the vehicle’s electrical accessories, such as headlights, dashboard instruments, and the radio, while also recharging the car's battery. Typically, it is driven by a belt connected to the engine's crankshaft.

⚙️How Does an Alternator Work?

The alternator operates using electromagnetic induction. It has three main parts: the rotor, stator, and rectifier. When the engine runs, the crankshaft turns the alternator’s rotor (a magnet or electromagnet), which spins inside the stator (a set of stationary wire coils).

As the rotor spins, it creates a magnetic field that induces an alternating current (AC) in the stator coils. Since the car's electrical system requires direct current (DC), a rectifier is used to convert AC to DC. Additionally, a voltage regulator ensures a steady output, preventing damage to the car's electrical components by keeping the voltage within a safe range.

⚙️Advantages of an Alternator:

✍️1. Efficiency: Alternators are more efficient than older generators, providing a steady power supply even at lower engine speeds.

✍️2. Battery Charging: They help keep the car battery fully charged, which is crucial for starting the vehicle and powering electronics when the engine is off.

✍️3. Longer Lifespan: Alternators are designed for durability, often lasting longer than other electrical components.

✍️4. Low Maintenance: Requires minimal upkeep, reducing overall vehicle maintenance costs.

Chillers Components
02/11/2024

Chillers Components

Silent But Deadly: The Secret Dangers of Worn Ball JointsWorn ball joints are critical components of your vehicle's susp...
27/09/2024

Silent But Deadly: The Secret Dangers of Worn Ball Joints

Worn ball joints are critical components of your vehicle's suspension system that, if ignored, can lead to serious safety hazards. These spherical bearings connect the control arms to the steering knuckles, enabling smooth movement and steering. Over time, wear and tear can result in several hidden dangers:

1. Loss of Steering Control

A worn ball joint can make steering unpredictable. You may experience a loose or shaky steering wheel, particularly when turning or navigating bumps. Complete failure could result in a loss of vehicle control.

2. Uneven Tire Wear

Ball joints help maintain proper wheel alignment. Worn joints can cause misalignment, leading to uneven tire wear, which shortens tire life and affects handling, increasing the risk of a blowout.

3. Suspension Damage

Worn ball joints can strain the suspension system, potentially damaging other components like control arms, bushings, and struts. This may result in more costly repairs and reduced ride comfort.

4. Noisy Operation

One of the first signs of a worn ball joint is noise, often manifested as clunking or knocking sounds, especially on rough terrain. Ignoring these noises can lead to further deterioration and unsafe driving conditions.

5. Risk of Ball Joint Failure

The most dangerous consequence of neglecting worn ball joints is total failure. A broken ball joint can cause a wheel to collapse inward or outward, resulting in a complete loss of steering control—particularly perilous at high speeds.

How to Avoid These Dangers:

Regular Inspections: Schedule routine checks of your suspension system, especially if you notice uneven tire wear, unusual noises, or loose steering.

Timely Replacement: If a mechanic identifies a worn ball joint, replace it immediately to prevent further damage or potential failure.

Neglecting worn ball joints can lead to accidents, expensive repairs, and life-threatening situations. Regular maintenance is essential for avoiding these hidden dangers.

Common rail fuel injection is a modern fuel delivery system used in both diesel and gasoline engines. It offers signific...
29/08/2024

Common rail fuel injection is a modern fuel delivery system used in both diesel and gasoline engines. It offers significant advantages in terms of performance, fuel efficiency, and emissions reduction compared to older injection systems.

How it Works:
- High-Pressure Pump: A high-pressure pump builds and maintains a constant pressure in the common rail. This rail is a pressurized tube that distributes fuel to all the injectors.
- Common Rail: The fuel is stored under high pressure in the common rail, ready for injection.
-Injectors: Each cylinder has its own injector. These injectors are electronically controlled to precisely control the timing, duration, and amount of fuel injected into the combustion chamber.

How Hydroelectric Power Generation WorksElectricity is vital for modern society. Most of us can't imagine life without i...
26/07/2024

How Hydroelectric Power Generation Works
Electricity is vital for modern society. Most of us can't imagine life without it and the various devices and services powered by it. There are various methods of generating electricity, but the most commonly used worldwide is hydroelectric power, which harnesses energy from flowing water to produce electricity.

How does Hydroelectric Power Generation work?
The process is quite simple. To produce hydroelectricity, flowing water is used to rotate large turbines. As the turbines spin, they create mechanical energy which is then transformed into electrical energy using generators.

Types of Hydroelectric Power Plants
1. Dam-based:
In this approach, dams are constructed to utilize the energy of water. The hydroelectric power plant is integrated into the dam. Water from the dam is released and channeled towards the turbines, causing them to spin and generate electricity. Water may also be stored in a reservoir at the base of the dam, which can be pumped back up to meet high electricity demands.

2. Run-of-river-based:
The process of generating electricity remains the same. The difference in this method is that instead of being built as part of a dam, the hydroelectric power plant is situated near a river. A small portion of the river is diverted to rotate the turbines in the plant and generate electricity.
Both methods have their advantages and disadvantages.

Pros and Cons of Hydroelectric Power Generation –
The dam method provides greater control over the generation process. It allows for water storage and controlled release, leading to more efficient electricity supply. However, dam construction is costly and has significant impacts on the surrounding environment and ecology. Additionally, the potential consequences of dam breakage are severe, causing widespread damage to the surrounding flora and fauna. These are all important considerations when constructing dam-based hydroelectric plants.
The run-of-river method has fewer negative effects on the environment. On the downside, it is reliant on the natural availability of water, leading to fluctuations in electricity supply and reduced control over electricity production.
In summary, hydroelectricity is the most widely used method of electricity generation globally for good reasons. It is a clean and renewable energy source, as it does not produce pollution and utilizes the constant renewal of water in the water cycle.

FUEL INJECTORSCommon Symptoms of Clogged Fuel InjectorsClogged fuel injectors can lead to several noticeable symptoms. T...
26/07/2024

FUEL INJECTORS
Common Symptoms of Clogged Fuel Injectors

Clogged fuel injectors can lead to several noticeable symptoms. These include:

- Engine misfires: When the fuel injectors are clogged, the engine may misfire or run unevenly. This can result in a rough idle, hesitation, or a loss of power during acceleration.

- Poor fuel efficiency: Clogged injectors can disrupt the fuel-to-air ratio in the combustion chamber, leading to decreased fuel efficiency and increased fuel consumption.

- Difficulty starting the engine: If the injectors are severely clogged, it may be difficult to start the engine, especially when the vehicle has been sitting for a while.

- Rough idling: Clogged injectors can cause the engine to idle roughly or inconsistently.

If you notice any of these symptoms, it is important to address the issue promptly to prevent further damage to your engine.

How to Diagnose Clogged Fuel Injectors Yourself

While professional diagnosis is recommended for accurate results, there are a few steps you can take to identify potential clogged fuel injectors yourself:

1. Listen for unusual sounds: Clogged injectors can cause a ticking or clicking noise from the engine.

2. Check for engine misfires: Look out for a rough idle or hesitation during acceleration, as these can be signs of clogged injectors.

3. Monitor fuel efficiency: If you notice a sudden decrease in fuel efficiency without any other apparent issues, it may indicate clogged injectors.

4. Inspect the exhaust smoke: Black smoke coming from the exhaust can be a sign of rich fuel mixture caused by clogged injectors.

If you suspect clogged fuel injectors based on these observations, it is recommended to consult a professional mechanic for a thorough diagnosis and appropriate cleaning.

11 Symptoms Of Bad Wheel Bearing1- Humming SoundThe first sign you will notice is the distinctive sound. It serves as a ...
26/07/2024

11 Symptoms Of Bad Wheel Bearing

1- Humming Sound
The first sign you will notice is the distinctive sound. It serves as a form of trademark for this issue.

Typically, first comes a barely audible buzzing sound that is readily confused with, for instance, an underinflated tire. As the issue worsens, though, the buzzing becomes nearly as loud as the engine in its latter stages.

2- Howling And Squealing Sound
In most cases, the humming is followed by a sound first described as a howl and later as a screeching.

As the wheel bearing sustains additional damage and uses up an increasing amount of its oil, it dries out. After that, the sounds are caused by an increase in the friction that exists between the inner metal parts. When you drive faster, more force is applied to the bearing, which increases noise.

3- Clicking Sound
When the problem has progressed to a later stage, you may hear a clicking sound from the wheel while driving. It’s not all that loud, but if you open the window while driving, you can hear it.

Initially, it sounds like a small metal ball striking the wheel, but it gets significantly more noticeable as time passes.

As was the case with the humming sound, this is easily misunderstood as a malfunctioning CV joint, for example. If this is the only symptom you are experiencing, it is essential to thoroughly examine the undercarriage to prevent making an error.

4- Grinding Sound
The wheel bearing has reached the end of its useful life when it begins to make a grinding sound. In most cases, this indicates that the bearing’s internal components are barely holding together and that a total failure of the bearing is on the horizon.

Even to the point where it’s possible for the bearing to become jammed, preventing the wheel from turning. There is a loud, distinctive sound similar to metal, and it sounds like bits of metal are grinding together. I feel obligated to point out that you should strive not to let the problem reach this point and act before the grinding begins.

5- Steering wheel vibration
A faulty wheel bearing might produce vibrations in the steering wheel, particularly if the front wheels are afflicted. If only the rear wheel bearings are faulty, the vibration is primarily felt beneath the seats.

Unbalanced wheels typically cause steering wheel vibration; consequently, you should only investigate a faulty wheel bearing if the vibrations are accompanied by a humming or grinding sound.

6- ABS Warning Light Comes Up On The Dashboard
Since the speed sensor is (in the vast majority of instances) placed within the same wheel assembly, the ABS warning light may illuminate. When the wheel bearing has reached the end of its useful life, it may wobble, leading to a fault in the ABS.

7- Wheel Wobble
This is one of the indications of a severely deteriorated wheel bearing. Similar to the grinding sound, if you see this symptom, you should immediately replace the wheel bearing. Since the bearing holds the entire wheel to the drive shaft, damage results in undesirable play.

This indicates that the entire wheel has undesirable play. The most typical cause of this is damage to the cage and rollers within the wheel bearing. This can be easily detected by raising the vehicle and attempting to rotate the wheel from side to side. The play will then begin.

8- Vehicle Pulls To One Side
Since the wheel is practically unbalanced, you may notice that your vehicle pulls to one side in addition to the wheel wobbling. It’s very similar to when a car’s tires aren’t correctly balanced or when one of the tires isn’t inflated to the correct level. In the beginning, the pull is hardly perceptible; nevertheless, if you do not take action in time, it may pull significantly to one side.

10- Steering Wheel Response
The fact that the wheel hub assembly on one side isn’t functioning correctly will manifest in the vehicle’s steering if the problem persists. It is possible that, rather than having the normal snappy response, it will feel somewhat delayed or as though it is putting up a bit of a battle. Overall, this is one of the negative symptoms associated with the wheel bearing, and it feels bizarre.

11- Greasy Marks On The Wheel Hub, Wheel Rim, Or HubCap
The last symptom on this list, greasy stains on the wheel hub or rim, is possibly the least obvious. In most cases, all of the initial symptoms are already present. Therefore you will likely not notice this. Nonetheless, if you see this, such as when changing a tire or performing an inspection, give it a second look. Make an immediate inspection if you notice thick, typically black or green, oil around the center of the wheel hub, on the inner portion of the wheel rim, or on the hubcap.

This is caused by a broken or missing seal on the bearing, which allows all lubricants to escape. Lacking lubrication, the wheel bearing will eventually become severely damaged.

Conclusion
When discussing problematic wheel-bearing symptoms, it is crucial to recognize them.

The crankshaft position sensor (CKP sensor) is a vital electronic component in your car's engine. It acts like a tiny sp...
26/07/2024

The crankshaft position sensor (CKP sensor) is a vital electronic component in your car's engine. It acts like a tiny spy, constantly monitoring the crankshaft's rotation.

Here's the breakdown:
- Function: It tracks the crankshaft's speed and position, sending this information to the engine control unit (ECU).
- Working Principle: As the crankshaft spins, a gear or wheel with teeth passes near the sensor. This disrupts a magnetic field, generating a signal for the ECU. The signal frequency represents engine speed, while the timing of the signal spikes reveals the crankshaft's position.
- Symptoms of a Faulty CKP Sensor: Engine stalling, trouble starting, rough idling, and inconsistent performance are common signs. Your check engine light might also come on.

Common DTC Codes (fault codes) associated with CKP Sensor:
- P0335 - Crankshaft Position Sensor A Circuit Malfunction
- P0336 - Crankshaft Position Sensor B Circuit Malfunction
- P0337 - Crankshaft Position Sensor Circuit Range/Performance Problem
- P0338 - Crankshaft Position Sensor Signal Voltage Out of Range Low
- P0339 - Crankshaft Position Sensor Signal Voltage Out of Range High
- P0340 - Crankshaft Position Sensor Circuit Malfunction (Bank 1 or Sensor 1)
- P0341 - Crankshaft Position Sensor Circuit Malfunction (Bank 2 or Sensor 2)
- P0342 - Crankshaft Position Sensor No Signal
- P0343 - Crankshaft Position Sensor Circuit Intermittent
- P0344 - Crankshaft Position Sensor Circuit Intermittent (Bank 1 or Sensor 1)

Torque ConverterThe vehicles and machineries with automatic transmission does not have a clutch, instead, it has a torqu...
21/07/2024

Torque Converter

The vehicles and machineries with automatic transmission does not have a clutch, instead, it has a torque converter. But, how a torque converter works or solves the purpose of a clutch? To give you an idea, it works on the same principle as the fluid coupling.
How a Torque Converter Works
As the name suggests, it converts the torque of the engine and transmits it to the transmission system.
As soon as the flywheel of engine starts rotating, the torque converter housing as well as the pump also starts rotating in same speed and direction. Because of the profile of the pump blades, the fluids inside the torque converter are pushed out centrifugally. Because of the pressure developed by the pump, the fluids are forced into the blades of the turbine and make it rotate in the same direction as the pump. The fluids enter to the outer periphery of the turbine and leave from the inner periphery and reaches to the stator blades there. The function of the stator is to guide the incoming fluid from the turbine to reach at a specific angle to the pump.
If the turbine is rotating at a speed lower than that of the pump (i.e., when the vehicle is accelerating) then the fluids from the turbine hits the front sides of the stator blades and the one way clutch prevents it from rotating. In this condition the fluids leave from the stator hits the pump at a “helping” angle to increase the torque (or multiply the torque) and thus increase the speed of the turbine.
When the vehicle achieves its constant speed, then the angle at which the fluids leaving from the stator change and no more torque multiplications happens.
While retarding, the speed of the turbine increases than that of the pump and the fluid from the turbine hits the back sides of the stator blades and make the stator rotate at the same direction as the pump and turbine and the fluid from the stator hits the pump in such angles that the torque reduces.
Major Parts of a Torque Converter
A torque converter typically has three major components: impeller or pump, turbine and stator or reactor.
Impeller or Pump: The pump is made up of blades and works very similar to a centrifugal pump. It is mounted rigidly with the torque converter housing (shown in blue). The whole torque converter housing in turns is mounted rigidly with the flywheel. So, it rotates with the flywheel.

Turbine: Constructions of the turbine is very much similar to that of the pump but the orientation of the turbine blades are opposite to that of pump. The turbine is mounted on transmission input shaft.
Stator or Reactor: The stator has very complex guiding blades arrangements. It is mounted by a one way clutch with the transmission housing. The one way clutch allows the stator to rotate in one direction and prevent it from rotating to another.
You will find the use of the torque converter in almost all sort of automatic transmission vehicles: from passenger cars to heavy off highway vehicles. The design of the blades of the turbine, stator and the pump is the key of how effectively a torque converter works.

DIFFERENTIAL SERVICING & REPAIRS.DIFFERENTIAL BASICSAs a vehicle goes around corners, the outside wheels have to travel ...
16/07/2024

DIFFERENTIAL SERVICING & REPAIRS.

DIFFERENTIAL BASICS
As a vehicle goes around corners, the outside wheels have to travel a greater distance than the inside wheels. While the difference seems minor, a vehicle is a precision machine, and small variances could do a lot of damage over the long run if not compensated for.

The Differential is responsible for this compensation in the driven wheels of a vehicle. It does so through a set of “spider” gears that mechanically transfer the torque from one wheel to the other. When one wheel needs to travel a smaller distance, it transfers some of its torque to the opposite wheel, which needs to travel the greater distance.

This automated torque balancing action keeps the overall load on the engine and transmission steady, regardless of how sharp the vehicle is turning. In doing so, the gears in the differential experience heavy and varying loads, which leads to heat and wear on all the mechanical components. To ensure smooth operation, the gears need to mesh perfectly and stay well lubricated.

That’s why they are bathed in thick, dense, gear oil that requires changing regularly to maintain its viscosity, friction reducing, and heat dissipation properties.

DIFFERENTIAL DESIGN
Differentials are normally designed for one of three types of operation: Open, Locked, or Limited Slip. A locking differential is designed to overcome the chief limitation of a standard open differential by essentially “locking” both wheels on an axle together as if on a common shaft. This forces both wheels to turn in unison, regardless of the traction (or lack thereof) available to either wheel individually. There are numerous variations such as manual and automatic locking designs, and several limited slip designs.

OPEN DIFFERENTIALS
An open (or unlocked) differential always provides the same torque (rotational force) to both wheels on the same axle. So although the wheels can rotate at different speeds, they apply the same rotational force, even if one is entirely stationary, and the other spinning.

LOCKED DIFFERENTIALS
By contrast, a locked differential forces both left and right wheels on the same axle to rotate at the same speed under nearly all circumstances, regardless of traction differences. Therefore, each wheel can apply as much rotational force as the traction under it will allow, but the torques on each side-shaft can be unequal.

A locked differential can provide a significant traction advantage over an open differential, but only when the traction under each wheel differs significantly.

All the above comments apply to central differentials as well as to those in each axle: full-time four-wheel-drive (often called “All Wheel Drive”) vehicles have three differentials, one in each axle, and a central one incorporated into the transfer case.

LIMITED SLIP
Limited Slip differentials are considered a compromise between a standard differential and a locking differential because they operate more smoothly, and they do direct some extra torque to the wheel with the most traction compared to a standard differential, but they are not capable of 100% lockup.

TRACTION CONTROL

Traction Control systems are also used in many modern vehicles either in addition to, or as a replacement of, a locking differential. This is not in fact a differential lock, but operates at each wheel. Sensors monitor wheel speeds, and if one is rotating significantly faster than the other the traction control system momentarily applies braking to the slipping wheel. This transfers more power to the wheel with traction by employing the open differential. If all drive wheels lose traction, then throttle control may be automatically applied. Electronic traction control systems are usually integrated with anti-lock braking systems, which have a similar braking action and use many of the same components.

DIFFERENTIAL SERVICE RECOMMENDATIONS
Most vehicle manufacturers recommend that the differential fluid be changed every 50,000 Km to 70,000 Km. We recommend even more frequently if the vehicle is used for towing or other heavy workloads. It is a messy job, and should be done by a licensed mechanic. The fluid will have to be disposed of properly, you may need new gaskets or seals, and the parts inside the differential housing will need to be wiped down so that any contaminants from the old fluid aren’t transferred to the new. Plus, the differential is underneath the vehicle so it will need to be lifted on a hoist for clear access.

During a differential service, our experienced technicians will diagnose any potential problems before they become significant. They can measure the float, run a gear pattern, set the preload, and inspect the axle and pinion bearings and seals. They’ll also inspect and make adjustments to any positive traction mechanisms to ensure they are optimized throughout the life of the vehicle. They can also repair any leaks that could lead to fluid loss and catastrophic failure of the differential.

YOU’VE HAD THE RING AND PINION GEAR SET IN YOUR DIFFERENTIAL REPLACED – NOW WHAT?

When you’ve had a new ring and pinion gear set installed in your differential, we highly recommend that you follow these break-in procedures to ensure the best performance and longevity from your vehicle.

After driving the first 20 to 30 Km, stop and let the differential cool down. Keep the vehicle at speeds below 100 KPH for the first 150 Km. We also recommend putting at least 750 Km on the new gear set before heavy usage such as towing. During the first 60 Km of heavy usage it helps to go about 20 Km at a time, then stopping to let the differential cool for 15 minutes before continuing. This is necessary because not all of the gear tooth surface is making contact until it’s heavily loaded. When loaded, the teeth flex to make more complete contact and cause the previously unloaded portion of the teeth to touch and become work-hardened. All of this may seem paranoid but it is very easy to damage new ring and pinion gears through overloading before the teeth are broken in. If you take it easy on a new gear set and keep the differential full of clean, high quality oil, it will last a lot longer.

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+9779840220387

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