Introduction
Wagon unloading is one of the important and quickest processes to have happened in material rail transit. Manual unloading from wagons is a highly time-consuming technique and requires enormous manpower. In earlier days, manual unloading was the only option. But in course of time, new mechanical technologies were developed for bulk material unloading. Excavators, Wagon tipplers, and chain bucket unloaders are the main types.
Different types of unloading machines
The type of machines is chosen based on the applications. Excavators and tipplers are the most common type of unloading machines. For various reasons, manual unloading is still employed in some factories. Because, not all facilities support the arrangements required for these mechanical technologies. There were scenarios where both these techniques cannot be employed. In such cases, manual unloading is employed, but a new variant, chain bucket unloaders show us new possibilities. Decide your type of unloader, by checking out about them.
Excavators
Excavators dig out the material from the wagon. Excavator hands with appropriate length and size dig out the material from the train wagon. Excavators are either elevated or side-mounted. The excavator can move alongside the rail or overhead to approach each wagon. It can be simply made by elevating a common excavator above a platform. The platform height must be chosen appropriately to enable complete unloading.
The overhead excavator will be placed on a movable platform over the top of the wagon while the side mounts dig from the side. Positioning the excavator above the rail car eliminates operator blind spots and is more efficient than side unloading. Excavators can either be moved through a rail track or using a bulldozer chain wheel.
Wagon tippler
Wagon tipplers are automated mechanical systems that tilt the wagon to unload. A wagon tippler is constructed along the railroad. Once the wagon reaches the unloading point where the wagon tippler is installed. The tippler clamps the wagon without any harm, then tilts the wagon to the side where hoover is located. The tippler will be programmed to tilt the wagon until the entire material is unloaded.
Side discharge and rotary tipplers are the main two types of wagon tipplers available. For free-flowing materials, side discharge tipplers are used. Rotary tipplers are used for solid materials. Tipplers are used for applications that are comparatively faster and bulk unloading is required. Compared to the excavators, tipplers require less manpower but wagons have to be disconnected from other wagons.
Chain bucket unloader
Chain bucket unloader is comparatively a new technology in the wagon unloading system. This type of unloader is used for both speedy and careful operations. It is a fully equipped machine that continuously digs out material from the wagon and safely displaces it out of the wagon. Unlike other unloaders, a chain bucket system won’t dumb material into the storage facility. Among the three technologies, the chain bucket could be the most flexible unloader.
The chain bucket excavators fitted to the rotating conveyor will dig out the material from the wagon. Then the material is fed to a conveyor belt which moves the material to storage.
Other attractions of chain buckets are their flexibility in designing to make them suitable for various applications. As mentioned above this is a new type of unloader, so we have to check more about this unloader.
Fixed type, rotary type, combined and movable different types of unloader machines available.
Fixed type
It is an unmovable structure built around the rail track, each wagon must correctly be positioned below the excavator. This type is mostly used where multiple railway tracks passing through or implementing separate running tracks for excavators is impossible. This type contains an inbuilt conveyor system that releases materials to the destination. It can also accommodate dust removing systems inside.
Buckets for most of the unloaders are designed for heavy-duty applications and stay upwards throughout the whole process cycle for cleaner performance. Putting it in an upward position has the advantage of stop spillage and thus reducing system pollution.
Features of fixed type:
- No lubrication is required on the chain
- Customizable for various type of applications
- Wash down capacity to ensure cleanliness.
- Different bucket size and belt size available
- Heavy and highly durable buckets can be employed
- Low maintenance is required
Rotary type
It is all the same as the other type of unloader. But this type can unload material at 180° at the massive storage yard. The process of excavating material from the wagon is the same but its dispense to the storage yard is at 180°. The dispensing conveyor belt is constructed along the track.
Comparatively huge chains are used to conveyor belts since it is subjected to heavy shock loads, and conveyed materials are heavily corrosive.
Features of Rotary type:
- This machine can unload material in a large quantity
- Due to its horizontal motion, it easier for the machinery to unload train wagons on several railway lines
- A proper dust removal system is recommended, since this type could produce a lot of dust.
Mobile type
As the name suggests it can move over the wagon. A separate track must be installed at both sides of the actual rail line for the excavator movement. Here the train can be stationary during the entire process of unloading. Only the excavator moves over the wagon and unloads the material. An extra unit used in the excavator unit will be the driver’s chamber. For a larger area of storage facilities, this type of excavator is the best.
Features of mobile type:
- Reliable and steady performance
- High capacity
- More smart features can be developed since the excavator is movable
- Power usage is minimal
- Good safety performance
Combined type
They are used where loaded material has to arrange in order in the storage facility. Once the machine lifts the material from the railway carriage to the belt conveyor, it transfers that to the end of the unloader. The material reaches the ground belt conveyor uniformly and slowly through the funnel to carry it to the destination.
Features of combined type:
- Suitable for both loading and unloading operations
- Able to unload material from wagons on several railway lines
- Can unload large quantities of material
Comparison of different types of unloading systems
We have briefly checked the features of the three main types of wagon unloading systems. No new special mechanisms are developed for unloading materials from wagons. Excavators, Tipples, and Buckets chain systems are also used in ports and other industries for unloading purposes. But considering the unique specialty of the work environment, special designs are required.
All three types are better than manual unloading and all of them succeed in automating the process. But how much? We cannot say excavators completely automated the process. It is just placing the common excavator on the top of a platform and the train passes under the elevated platform. It is an advanced version of manual unloading. Of course, it is alright for unloading a smaller number of wagons, and installation costs are comparatively low. But even in that, we have to work again with the material to stack or arrange them in a proper place. We have to shift it. For bulk load with a larger number of wagons and for long-time use, excavators are no perfect option.
On the other hand, we have wagon tipplers. They have more than one century’s proven track record in unloading services across the globe. And numerous updations were introduced to tippler design and automation in time. All the updations were regarding the process of tippler and that process ends when the tippler dumbs the material to the hopper. From the hopper, the material should be removed in time before the next batch of wagon unload. A conveyor system will be used to transfer the material from the hopper that requires extra work time. For coals and port facilities, tipplers are a good choice, if tippler installation, hopper construction is affordable. Otherwise, it is one of the best options for the quick unloading of wagons.
Finally, we have a chain bucket unloader, which is a better-automated machine. Unlike the other unloaders, chain bucket unloaders have inbuilt feeders to properly store material. The main attraction of chain bucket unloaders is that they are available in different variants. As this type of unloader employs buckets of different sizes and shapes they are suitable for unloading all types of materials. While wagon tipplers are not movable and excavators are not suitable for quick operation, the chain bucket unloaders provide both. Regardless of the type of bucket unloader, it is suitable for any time storage facilities. It is perfect for tanks or open yard storage.
Chain bucket unloaders are suitable for both permanent and temporary setups. It can be easily moved to the next location. Furthermore, its conveyor facility increases its unloading flexibility.
Summary
There is no doubt that choosing an unloading system completely depends on the application. But we were trying to take the best across various applications. We studied the different types of unloading systems namely, Excavators, Wagon tipplers, and Chain bucket unloaders.
Out of the three chain bucket unloader is the perfect blend of speed and precise material handling. It provides a variety of customizable options which are chosen based on the client application. Chain bucket unloader will play a prominent role in automating the bulk material handling industry.