Cold aggregate feed system

I hop you know very well about drum mix asphalt plants which consist various types of components in which Cold aggregate feed system also exists. Then what is cold aggregate feed system? Yes it is essential to feed these mixers with accurate proportions of aggregate sizes. Multi compartiment bin feeder system ensures this accuracy. Number of bin hoppers vary on the requirement of asphalt mix specifications, however 3 to 5 bin systems are common. Each bin hopper is loaded with a specific size of aggregate which is discharged on the collecting conveyor. These bin hoppers are mounted on a rigid frame. In a mobile plant these are mounted on a robust chassis and are fitted with pneumatic tyres.

Each bin has independent belt feeder under it driven by independent and mutually synchronized variable speed electric motors. Each bin hopper is fitted with precision adjustable quadrant gates. With the variable speed electric motors fitted with technogenerator, belt speed can be accurately varied to regulate the rate of aggregate flow from the bin. When discharge rate of each aggregate is required to be controlled by weight, weighing system is provided on each belt conveyor to indicate the weight in T.P.H. (tons per hour) on gauges in the operator's cabin is provided. Synchronized variable speed motor is provided to increase or decrease the aggregate flow in same proportion from each bin in order to increase or decrease the production of mix. Smallest size aggregate hopper is fitted with anti logging electromechanical vibrator on one of the side plates to maintain continuous flow of material.

Filler is accurately proportioned by screw conveyor with variable speed motor, from a bulk storage silo or bag filled arrangements. Filler is fed on to the collecting (or some times called gathering) conveyor (described in the following paragraph) after the sand but before the stone aggregate, thereby securing the filler within a feed "sandwich". Filler may be mineral dust, lime or cement. Sometimes these are directly fed into the mixing zone of the dryer drum.

Gathering conveyor collects the discharge from each of the independent belt conveyor and is equipped with electronic weigh bridge and a suitable size electric motor. The weight of the aggregate in T.P.H. is indicated in the cabin.

Belt weigher is fitted with each of the conveyor belt to record the weight of the aggregate in T.P.H. passing over it. In volume control system, belt weigher is provided with gathering conveyor to know the production rate of mix from the plant. Wherever control of aggregate is by weight, belt weighers are provided with each of the belt peeder and also with gathering conveyor. The belt weight constantly monitors the materials feed rate. A signal from the belt weigher is transmitted to the plant control system so that adjustments can be automatically effected.

Scalping screen: Feed material entering the drum mixer is required to be accurately sized, so where there is the possibility of oversize material or unwanted elements contaminating the feed aggregate, a seelping screen is installed between the cold feed gathering conveyor and the weigh conveyor which is discharging into the drum mixer.

Drum mix asphalt plants

Drum mix asphalt plants are becoming more and more popular because, initial capital investment cost of these plants is less than that of conventional batch, type asphalt mix plants, and running costs are also greatly reduced due to fewer moving and wearing parts.

These plants consist of following main components:
1. Cold aggregate feeder with mineral filler supply system.
2. Dryer and mixing unit with Dust collection system.
3. Bitumen storage, heating and delivery system.
4. Mix storage unit.
5. Operator cabin and controls.

How to achieve long life of under carriage

I hop you know very well about under carriage. Now you can see the following are the few tips which help in getting long life of under carriage as given below:

1. Try to avoid unnecessary high speed operation.

2. Try to avoid sharp and pivot turn.

3. Try to avoid reverse direction travelling.

4. Try to avoid loading only on one side for long period of time.

 5. Try to avoid track shoe slip under undue load.

6. Try to avoid riding over big boulders.

7. Try to avoid leaving a machine stopped on slant.

8. Try to avoid turning machine only in one direction.

9. Try to follow maintenance schedule as recommended by manufacturer.

Under carriage construction

During operation, the under carriage components are subject to high impact load, severe wear condition due to riding over metal to metal, working in mud, hard gravel and hard stone. In order to meet this requirement, undercarriage components are manufactured with wear resistant materials.

An under carriage unit consist of:
1. Track frame
2. Equaliser bar
3. Sprocket
4. Front idler
5. Track rollers
6. Carrier rollers
7. Track chain assembly
8. Guards

Civil Engineer and Building Construction

A good civil engineer is having very big relationship with building construction. Come, first of all we talk about the term building. The dictionary meaning of building is very simple. It simply indicates anything that is built with walls and a roof. The term building in civil engineering parlance is used to mean a structure having various components like foundations, walls, columns, floors, roofs, doors, windows, ventilators, stairs, lifts, various types of surface finishes, etc. As a civil engineer is mainly concerned with the construction of buildings, it is essential for him/her to acquire good knowledge of construction of various components of a building.

The society requires the building for its various activities and accordingly, the buildings can be grouped for convenience as follows:

1. Business buildings like offices, courts, shops, banks etc.

2. Worship buildings like churches, temples, mosques etc.

3. Residential buildings such as flats, row houses, bungalows etc.

4. Recreation buildings like theaters, town halls, cinemas etc..

5. Health building like hospitals, nursing homes etc.

6. Educational buildings like schools, colleges, universities etc.

7. Storages buildings like godowns, warehouses etc.

8. Industrial buildings like factories, laboratories, workshop etc.

As far as the construction of any building is concerned, the procedures laid down for its various components are more or less the same and the engineer has to select the appropriate method for the type of building to be constructed.

Run off

Maximum persons are having idea about the run off. If you know just share your knowledge here or add this knowledge in your mind about it. Run off means the draining or flowing off of precipitation from a catchments area through a surface channel. It thus represents the output from the catchment in a given unit of time. Consider a catchment area receiving precipitation. For a given precipitation, the evapotranspiration, initial loss, infiltration and detentions storage requirement will have to be first satisfied before the commencement of runoff.

Air Transport System

In the world various types of transport systems are there as per condition. But mainly three types of transport systems can be considered. The three types of transport named as land transport, water transport and air transport. Due to non-availability of water source in sufficiently only land and air transport is applicable. In spite of above transport there is one more means of transport named as railway transport. But in all transports air transport is most quick with respect to time. By using the air transport we can get so many benefit. We can tell those benefits as advantage of the air transport. The advantages of air transport are given as below:

1. Accessibility.
2. Continuous
3. Demand for technical skill
4. Emergency use
5. Engineering use.

In engineering technology generation whatever we use a few disadvantages may be there. In the same way, whenever we are using the air transport few disadvantages occur because the air transport is also the result of engineering technology. In air transport a few disadvantages are there which are given as below:

1. Flight rules
2. Operating expanses
3. Safety
4. Weather condition

But the engineering care always tries to provide the best technology where more and more advantages will be there and very very less disadvantages so that the people can enjoy their life with safety and cure. So we can use the air transport without any hesitation with all rules and regulation.