HIGH VOLUME, HIGH CAPACITY LIGHTWEIGHT ALUMINUM CONSTRUCTION BOTTOM DISCHARGE HOPPER WAGON ‘BOBRN-AB’
OBJECTIVE OF APPLICATION
The present invention proposes a high volume, high capacity, lightweight Aluminum construction Bottom Discharge hopper type wagon for haulage of bulk commodity on the Indian Railways.
BACKGROUND OF THE INVENTION
Bottom discharge Hopper type wagons are currently used extensively in India for the transportation of Coal, Iron Ore, and other high bulk density materials. Material is loaded through silo top loading and unloaded through a bottom discharge door in the wagon. The bottom discharge door mechanism is operated by a pneumatic / electro-pneumatic spool valve that actuates the bottom doors for discharge of material. The current type wagon in operation is manufactured in Steel and is suitable for a 22.32 tonnes axle load with a maximum payload capacity of 63.67 tonnes. Current grade of Steel used in the wagon construction is a fairly heavy construction and thus offers a low effective haulage considering a payload to tare ratio of 2.48:1. The effective volumetric capacity of the wagon is in the vicinity of 56 cubic meters.
With the emerging need for capacity augmentation of hopper type wagons with a high payload, research and development work commenced in order to introduce a higher volume, higher capacity hopper wagon suitable for the haulage of higher quantities of bulk commodity effectively and efficiently. The proposed invention wagon is designed with a longer length than the existing wagon between headstock to suitably incorporate higher volumetric capacity and a higher payload bearing capacity. A higher axle load bearing bogie being currently available on the Indian Railways, shall be incorporated for operation on the proposed wagon to support the

high payload. The wagon design also proposes an all Aluminum superstructure construction to significantly reduce the tare weight. This high volume, high capacity and lightweight Aluminum construction bottom discharge hopper type invention wagon proposes the following features over the existing bottom discharge hopper type wagon:

OBJECT OF THE INVENTION
The main objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper wagon that introduces an improved design to transport bulk commodity on the Indian Railways network with a high volumetric capacity by lowering the floor height of the wagon, having wider end wall hopper angles, and extending the overall length of the existing hopper type wagon.
Another objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper invention wagon that provides an improved design with a high payload capacity attributed to the expansion of internal wagon loadable area and thus facilitating higher loading ability.
A still another objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper wagon that utilizes a lightweight low height bogie with an axle load bearing capacity of 25 tonnes with suitable spring group arrangement that supports the higher payload proposed in the invention.

A further objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper wagon that utilizes Aluminum on the wagon body super structure construction to significantly reduce the empty weight of the wagon.
Another objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper wagon that suitably incorporates an underframe slung hybrid brake system to provide enhanced braking, a shorter braking distance, and a lower installation and maintenance cost over the existing bogie mounted braking system.
A further objective of the invention is to develop a high volume, high capacity, lightweight Aluminum construction bottom discharge hopper wagon that utilizes a single link bottom discharge door mechanism on the wagon that has a higher discharge rate and larger door opening to support the higher payload material being transported on the wagon. This single link door also effectively reduces the net maintainability of the door mechanism due to lesser number of total components and flaps on the door.
DRAWINGS OF THE INVENTION
Figure 1 – Diagram drawing of the existing Bottom Discharge Hopper Wagon Figure 2 – Diagram drawing of the proposed Invention Wagon Figure 3 – Diagram drawing of proposed single link door mechanism Figure 4 – Diagram drawing of LWLH Bogie Figure 5 – Diagram drawing of CASNUB Bogie

SUMMARY OF THE INVENTION
The said invention proposes an Aluminum construction high volume, high capacity, lightweight bottom discharge Hopper type wagon for the haulage of bulk commodities on the Indian Railways Network. The said invention proposes to implement an Aluminum construction super structure that shall reduce the empty weight of the wagon. A High strength low allows (HSLA) Steel construction of the underframe shall also reduce the tare weight of the wagon thereby aiming towards a further lower empty wagon weight. The invention wagon is designed to have a high volumetric capacity with the inclusion of the existing LWLH25 bogie currently plying on the Indian Railways. The distal end walls of the wagon i.e. the hopper wall angle at distal end has been made wider to accommodate more material in the said invention wagon and thus contributing to the cause for high volumetric capacity. The enhancement in the volumetric capacity is also achieved by increasing the net length of the wagon over the existing hopper type wagon. A lightweight low height (LWLH25) bogie under the super structure also contributes towards reduction of empty weight by utilizing a lower diameter wheel and a light construction bogie over the existing type 1000 mm wheel diameter CASNUB Bogie. This LWLH bogie effectively has a higher load bearing capacity of 25 tonnes per axle with suitable spring group arrangement and thus supports the higher payload on the invention wagon. The developed wagon with a higher volume and load bearing capacity introduces a single link bottom discharge door mechanism that proposes a higher discharge rate than the existing type hopper wagon door mechanism. This single link door mechanism proposes larger door openings to quickly discharge the bulk material from the wagon body. The door mechanism incorporates three single link Stainless Steel doors that pan across the width of the wagon at longitudinal intervals and account for two door openings each at the bottom of the wagon super structure. The proposed door mechanism is thus, more efficient than the existing type door mechanism.

The invention wagon also incorporates an underframe slung hybrid brake system that is relatively inexpensive over the existing bogie mounted brake system and provides an enhanced braking characteristics and a better braking distance.
DETAILED DESCRIPTION OF THE INVENTION
In the present invention the wagon utilizes two LWLH25 840 mm diameter wheel bogies of 25 t axle load under the Aluminum super structure to attain a low empty (Tare) weight and high payload bearing capacity to suitably address the need for capacity augmentation for bulk commodity transport on the Indian Railways network. The invention proposes a longer length of the wagon while keeping the overall dimensions within prescribed dimensions of Indian Railways that effectively provides a higher loadable volume of 72 m3 thus supporting the high payload capacity. The overall width and height of the super structure has remained the same as is available in the existing wagon to suit the schedule of dimensions.
The wagon under invention appropriately complements the large payload capacity with an enhanced volumetric capacity of 72 m3 for carrying bulk commodities. This high volume in the developed wagon is attained by increasing the overall length from what was available in the existing wagon between headstocks to provide more space for loadable bulk material in the hopper super structure. A wagon with longer length thus facilitates positioning the bogies a bit further away from each other and thus a longer distance between the bogies centers placed at distal ends at the bottom of the super structure. With the bogies being placed further with a greater bogie center distance, the super structure hopper with angled distal end walls are proposed further outward longitudinally at a wider angle to provide a higher loadable volume within the wagon. With the introduction of LWLH25 bogies below the super structure, the floor

height was taken further lower than the existing design wagon attributed to the lower diameter wheel of LWLH bogie and a small construction. With a lower floor height, enhancement to loadable volume was further facilitated.
The design parameters of the wagon under development proposes adoption of Aluminum for construction of body side walls and end walls to effectively provide a lighter construction wagon with a low tare weight. The material strength for the lighter Aluminum sheets used for construction is comparable to that of the existing grade of Steel being used in the current wagon construction. A High Strength Low Alloy grade Steel shall be used for the construction of the cold rolled form sectioned Center Sill and the entire under frame. Under frame being the support fishbone structure of the wagon forms an integral part in terms of flexural rigidity of the wagon. Aluminum adoption of desired thickness and Grade on the super structure along with a lightweight HSLA Steel Grade underframe significantly reduces the empty weight of the wagon. This lightweight construction essentially provides for a higher payload bearing capacity and higher material per tonne carriage capability thus providing for a more economic freight transport for a given tare weight of the wagon.
This developed wagon suitably proposes an underframe slung hybrid brake system on the wagon that provides for much better braking force and a shorter braking distance over the existing bogie mounted brake system. This proposed brake system is also relatively cheaper than the existing bogie mounted brake system in terms of installation cost and subsequent cost of maintenance during operation. This shall serve as a cost effective and efficient brake system for the higher payload carried per wagon.

This developed wagon also proposes a single link bottom discharge door mechanism that pans across the bottom width of the wagon superstructure positioned at longitudinal intervals between the distal end bogies. This door mechanism consists of three single link stainless steel doors with each door extending across the center sill laterally to cover two door openings of a larger opening area than the one available in the current hopper type wagon. Three doors with six door openings cumulatively provide a much bigger area for the discharge of material and a higher discharge rate to offload the bulk material from the wagon. This single link door mechanism is operated electro – pneumatically through a spool valve that has lever connections to the entire three individual doors that are hinge laterally along the width of the wagon at longitudinal intervals for discharge of material.

WE CLAIM
1. A high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon comprising:
- a super structure consisting of plurality of side wall assembly (2) and end wall assembly (3) and an underframe assembly (1), the said underframe assembly (1) being mounted over two LWLH 25 (lightweight low height) bogies (5) placed at distal ends;
- Each of the said bogies being mounted over TWO wheel sets (two axles placed longitudinally apart) with each wheel having a lower wheel diameter 840 mm (6), and each axle having a load bearing capacity of 25 tons;
- a single link bottom discharge mechanism (10) with three single link doors (9) that cover the door openings while being hinged and positioned laterally below the wagon at longitudinal intervals between the two consecutive bogies (5);
- an easy maintenance low cost underframe slung hybrid brake system (7) having a substantially low cost of maintenance and a high braking power
- the wagon encompasses a high strength low alloy steel grade underframe (1) below the superstructure, that includes an all aluminum lightweight wide angled hopper structure construction of side wall assembly (2) and end wall assembly (3) above a bottom hopper arrangement (4) constructed of High strength Steel thus providing an efficient and cost effective wagon with more material per tonne for a given empty weight of the wagon.

2. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 1 wherein a low tare weight of the wagon is achieved by extensive usage of Aluminum on the superstructure construction.
3. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 2 wherein the low tare weight is also achieved using a lightweight High Strength Low Allow Steel for the construction of the underframe of desired strength.
4. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 1 wherein the light payload is supported by the LWLH 25t axle load bogie with a suitable spring group arrangement, bogie with a lightweight construction and 840 mm wheel diameter.
5. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 1 wherein a high volume is achieved by extending the overall length by using a longitudinally wider angled end wall construction of the superstructure.
6. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 1 wherein quick and efficient discharge of material is achieved by incorporating a single link bottom discharge door mechanism with three single link large doors.

7. The high volume high capacity lightweight Aluminum construction bottom discharge type hopper wagon as claimed in claim 1 wherein a better braking distance is achieved by incorporating a cost effective and improved braking system with better braking and a lower cost of installation and maintenance.