 Hello, learners. Best greetings of the time to all of you. I am Mr. Shashikant B. Gosavi, Assistant Professor, Department of Civil Engineering, Vouchand Institute of Technology, SolarProm. Today I am going to present you the online educational resource on operating efficiencies of Dragline. The learning outcomes of today's online educational resource are the learners will be able to analyze the operating efficiencies of Dragline and the learners will be able to calculate the operating efficiencies of Dragline at the end of this session. This is a construction equipment well known as Dragline. You can see it basically consists of a tool in the form of a bucket which is dropping down with the help of a hoist cable which is connected to the operating cabin like this. The bucket is also connected with the operating cabin with the help of a drag cable and then the hoisting force as well as dragging force both of them are operated through the cabin. There is a boom to support these particular two form of the trusses which form the different parts of a Dragline. Dragline is a construction equipment used for excavating softer material. Trenches, canals and mines are the prime locations where this excavation happens and besides that it is particularly suited at lower level than its platform level. The Dragline consists of dragging a bucket on the material being excavated. It also dumps the excavated material for a longer distance as compared to conventional excavation equipment such as the power shovel or the backhoe or some such type of equipment. So, particularly suited when excavation and dumping is to be done in a single go. The sequence of Dragline activities consists of dragging the material towards the Dragline to feel the bucket. In the earlier sketch we have seen that there is a bucket and there was a drag force being applied from the cabin and the respective bucket was supposed to get pushed. Swinging the bucket along the predefined path, the path has to be predefined, unloading the bucket at a specified location, swinging back the bucket along predefined return path and adjusting the bucket to keep ready for the first step of dragging. This is the cyclic operation and therefore at the end once again we reach back to the starting step which continues in a cyclic form. You can see the sketch where the cycle time calculations will be calculated on different operations. The operation is actually broken into several cycles. The first operation as has been shown over here is you start of digging cycle. So, the cable will be pulled and the respective bucket will be pulled. In this particular case that respective bucket will be empty and then it will move to the second stage where the digging cycle will be completed. So, the empty bucket will get filled in this particular style. So, within this particular part the dragging will happen, material will get filled and then the field bucket will start moving in this fashion. It will move in this fashion. It will reach to a particular height from where it will be dumped down and then it will become empty. The empty bucket will be once again taken back to the starting point. So, if you look to it as a horizontal cycle, this will be a horizontal path. Again there will be maybe zigzag path, dumping will happen and then it will come back to the starting point. So, cycle will keep on repeating. Remember here the angles have been shown over here that swing angle is 0 while here it is 90 degree. The bucket loading time will be combination of all these particular operations. If you will see in the vertical frame once again there will be several cyclic operations. The first is start of the digging cycle. So, respective bucket will be dragged onto the vertical surface. It will get filled and therefore the loaded bucket will get swing like this. It will reach at the top. Then the material will be dumped down at the given location. Again it will be brought down as empty swing. It will reach to the end of the digging at this particular position. So, either in a horizontal direction or in a vertical direction these particular operations are basic operations for the respective drag line. The factors which influence the operations of the drag line consist of number one cut width and depth. The bucket is having the cut width and there will be a depth up to which the cutting gets to be done. The second is nature of the material being excavated. If it is a fragmented material obviously it will be easier for us to pick it up. If big size particles are there the bucket may not give you proper support. It will take its own time or if cohesive material is there the bucket will take its own time for getting the things excavated. The mode of excavation is another important factor which really affects onto the operation of the drag line. Bucket capacity is either smaller or larger also matters. The angle of the swing is very, very important. Then there is skill of drag line operator which has to come into the picture and more importantly the condition of the equipment itself. All these operations are supposed to really make changes into the total cycle time and indirectly total time required for completing the whole operation. Particularly for the angle of the swing it is a linear function but still then some constant are required to be added into the time required for swing. So it is like linear equation of mx plus c where the angle of the swing will be one of the function for which some efficiency will be consumed and that will be affecting on to the overall operation of the drag line. You can see the sequence of operations. Upper bench has been shown over here where the equipment is currently staying and this is an example of a coal quarry. Top soil is over here on which the equipment is there. It is dragging from here and then putting it on the front side. It is needed to really form a key and therefore to begin with you normally have to keep this much material at the bottom when you are moving downwards. So this particular material will be continuously excavated and then shifted and dumped down in this particular part. As you can see over here this particular part has got formed. The drag line has gone downwards and it will be forming a spoil in a similar shape just behind the previously existing spoil. The lost operation is the drag line has gone further ahead on to the part where the dumping was done. It can move ahead and this just behind it proper ramming will be done or you can have the boulders placed which will help us in forming the respective operation. You can see at the end over there that the respective operations will really give you a sense of operations required for the drag line. I request the learners to pause the video for a while and answer following questions. What is the effect of swing angle on efficiency of drag line? Secondly, please think on how does the size of bucket relate with efficiency of drag line? The effect of swing angle is directly proportional to the efficiency of drag line. I mean efficiency of drag line will keep on increasing as the swing angle will increase but then it is in a linear equation form. While the second is how does the size of bucket relate with efficiency of drag line? Smaller size of bucket obviously will move faster as compared to larger size of bucket. It will take its own time for the larger bucket to excavate the material. So, one has to think of optimizing this particular thing but still then if you will think of size moderation is at most essential. Smaller bucket requires lesser cycle time but more number of cycles while larger bucket size requires larger cycle type lesser number of cycles. I have used these references for studying the cycle time analysis and operational efficiency of the drag line. Thank you very much.