Oscillating Conveyor System

Selection of vibratory conveyor:

The oscillating motion of the trough is achieved via specially designed inclined arms and an eccentric shaft driven by a motor through V-belts. The eccentric shaft is mounted on anti friction bearings and has V-pulleys at both ends with weights on them to counteract the unbalancing force. The rotation of the eccentric shaft provides a forward and backward motion to a connecting arm attached to the trough through a rubberized pin. The trough motion is predominantly horizontal with some vertical component, which causes it to oscillate with a pattern conductive to conveying material. A retaining spring assembly at the back of the trough absorbs shock load. All components including drive motor are mounted on a rigidly constructed base frame.

Advantages:

· Hot and abrasive materials can be handled

· Cooling, drying and de-watering operation can be done during transport

· Scalping, screening or picking can be done

· Units can be covered and made dust tight

· Simple construction and low head room

· Can be made leak proof

Disadvantages:

· Relatively short length of conveying ( about 50m Maximum)

· Limited capacity, about 350 tons per hour for length of conveying of 30 m.

· Some degradation of material takes place.

Applications:

Vibratory conveyors find wide spread application in the transportation of dusty, hot, toxic, and chemically aggressive bulk material through a closed trough or pipe in chemical, metallurgical, mining industries and manufacturing of building materials.

Vibratory conveyors are also employed for transportation of steel chips in machine shop, hot knocked out sand, wastes and small castings in foundry shop. Vibratory feeders are also in use for delivery of small machine parts like screws, rivets etc.

Sticky materials like wet clay or sand are unsuitable for vibratory conveyors. In handling finely pulverized materials, like cement etc., the performance of such conveyors are reported to be poor.

Vibratory conveyors are hardly employed for handling common bulk loads, such as sand, gravel, coal etc as the same can be done more efficiency by belt conveyors.

FAILURE ANALYSIS

• Why ?

As the standards of our industry rise due to increasing globalization and competition, there is an ever growing need for consistency and reliability. Breakdown of any unit, system or equipment is an avoidable and costly occurrence and must be prevented or minimized. Analysis of such failures becomes a resourceful and affordable tool in addressing such unwanted occurrences.

To establish whether the cause of component failure lay on:

a) Service conditions
b) Design considerations
c) Material and its specification
d) Improper processing and assembly procedures or
e)  Combinations of these.

Only the real “Root cause” can ensure the effectiveness of corrective and preventive actions and avoid recurrence of failure.

• Stages Of Failure Analysis

1. Understanding and assimilation of background data and selection of samples.
2. Examination and documentation of the failed part by the following

1. Visual examination of parts, location (if necessary) and relevant photographs as well.

2.  Non destructive testing by means of Radiography, Dye      penetrant, Magnetic particle testing etc.

3. Mechanical Testing for various physical properties.

3. Vital specimens are selected, classified, and subjected to:

1. Macroscopic examination and analysis. This involves examining the fracture surfaces, secondary cracks, deposits and other such elements
2. Microscopic examination and analysis of fracture surface (by Scanning Electron Microscopy, if required).

4. Chemical analysis of material for conformation to specifications.

5. Chemical analysis of corrosion products, deposits, contaminants etc.

6. The actual state of the failed part and the failure mode are established.

7.  Fracture mechanics study if found necessary.

8. A simulation of the identical working environment to determine if any external      factors have contributed to the failure

9. Conclusions are determined after compiling all evidences and analysis and       then the report is generated.
10. Follow-up recommendations are also provided.

Artificial photosynthesis

Artificial photosynthesis is one of the newer ways researchers are exploring to capture the energy of sunlight reaching earth.

Photosynthesis:

Photosynthesis is the conversion of sunlight, carbon dioxide, and water into usable fuel and it is typically discussed in relation to plants where the fuel is carbohydrates, proteins, and fats. Using only 3 percent of the sunlight that reaches the planet, plants collectively perform massive energy conversions, converting just over 1,100 billion tons of CO2 into food sources for animals every year.

Photovoltaic Technology:

This harnessing of the sun represents a virtually untapped potential for generating energy for human use at a time when efforts to commercialize photovoltaic–cell technology are underway. Using a semiconductor–based system, photovoltaic technology converts sunlight to electricity, but in an expensive and somewhat inefficient manner with notable shortcomings related to energy storage and the dynamics of weather and available sunlight.

Artificial Photosynthesis:

Two things occur as plants convert sunlight into energy:

• Sunlight is harvested using chlorophyll and a collection of proteins and enzymes, and
• Water molecules are split into hydrogen, electrons, and oxygen.

These electrons and oxygen then turn the CO2 into carbohydrates, after which oxygen is expelled.

Rather than release only oxygen at the end of this reaction, an artificial process designed to produce energy for human use will need to release liquid hydrogen or methanol, which will in turn be used as liquid fuel or channeled into a fuel cell. The processes of producing hydrogen and capturing sunlight are not a problem. The challenge lies in developing a catalyst to split the water molecules and get the electrons that start the chemical process  to produce the hydrogen.

There are a number of promising catalysts available, that, once perfected, could have a profound impact on how we address the energy supply challenge:

• Manganese directly mimics the biology found in plants.
• Titanium Dioxide is used in dye-sensitized cell.
• Cobalt Oxide is very abundant, stable and efficient as a catalyst

Artificial Photosynthesis Operation:

Under the fuel through artificial photosynthesis scenario, nano tubes embedded within a membrane would act like green leaves, using incident solar radiation (H³) to split water molecules (H2O), freeing up electrons and oxygen (O2) that then react with carbon dioxide (CO2) to produce a fuel, shown here as methanol (CH3OH). The result is a renewable green energy source that also helps scrub the atmosphere of excessive carbon dioxide from the burning of fossil fuels.

History:

Plants use organic compounds that need to be continuously renewed. Researchers are looking for inorganic compounds that catalyze the needed reactions and are both efficient and widely available.

The research has been significantly boosted by the application of nano technology. It’s a good example of the step wise progress in the scientific world.

Studies earlier in the decade showed that crystals iridium efficiently drove the reduction of CO2, but iridium is extremely rare so technology that required its use would be expensive and could never be used on a large scale.

Cobalt crystals were tried. They worked, and cobalt is widely available, but the original formulations weren’t at all efficient.

Things changed with the introduction of nano technology.

The main point is that this unique approach increasing appears to be feasible. It has the advantage of harnessing solar energy in a form that can be stored and used with greater efficiency than batteries and it is at least carbon neutral.

HOW FUEL CELL WORK?

An electrochemical reaction occurs between hydrogen and oxygen that converts chemical energy into electrical energy.

Think of them as big batteries, but ones that only operate when fuel—in this case, pure hydrogen—is supplied to them. When it is, an electrochemical reaction takes place between the hydrogen and oxygen that directly converts chemical energy into electrical energy. Various types of fuel cells exist, but the one automakers are primarily focusing on for fuel cell cars is one that relies on a proton-exchange membrane, or PEM. In the generic PEM fuel cell pictured here, the membrane lies sandwiched between a positively charged electrode (the cathode) and a negatively charged electrode (the anode). In the simple reaction that occurs here rests the hope of engineers, policymakers, and ordinary citizens that someday we’ll drive entirely pollution-free cars.

Here’s what happens in the fuel cell: When hydrogen gas pumped from the fuel tanks arrives at the anode, which is made of platinum, the platinum catalyzes a reaction that ionizes the gas. Ionization breaks the hydrogen atom down into its positive ions (hydrogen protons) and negative ions (electrons). Both types of ions are naturally drawn to the cathode situated on the other side of the membrane, but only the protons can pass through the membrane (hence the name “proton-exchange”). The electrons are forced to go around the PEM, and along the way they are shunted through a circuit, generating the electricity that runs the car’s systems.

Using the two different routes, the hydrogen protons and the electrons quickly reach the cathode. While hydrogen is fed to the anode, oxygen is fed to the cathode, where a catalyst creates oxygen ions. The arriving hydrogen protons and electrons bond with these oxygen ions, creating the two “waste products” of the reaction—water vapor and heat. Some of the water vapor gets recycled for use in humidification, and the rest drips out of the tailpipe as “exhaust.” This cycle proceeds continuously as long as the car is powered up and in motion; when it’s idling, output from the fuel cell is shut off to conserve fuel, and the ultra capacitor takes over to power air conditioning and other components.

A single hydrogen fuel cell delivers a low voltage, so manufacturers “stack” fuel cells together in a series, as in a dry-cell battery. The more layers, the higher the voltage. Electrical current, meanwhile, has to do with surface area. The greater the surface area of the electrodes, the greater the current. One of the great challenges automakers face is how to increase electrical output (voltage times current) to the point where consumers get the power and distance they’re accustomed to while also economizing space in the tight confines of an automobile.