Internal drainage system for hollow member structural assembly and method

An internal water drainage system for an interconnected hollow structural assembly within a railroad pressure discharge hopper car or the like is disclosed. To facilitate water drainage throughout the interconnected hollow structural assembly following hydrostatic pressure testing of the car, water draining passageways are provided in the hollow structural members in an area of juncture between the members, at least along a lowermost extent of each of the hollow structural members. The water drainage passageways are constructed to communicate with a water drain opening provided in the shell of the railroad car, in order to afford gravity flow of water through the hollow structural members and evacuation from the railroad car. A method for hydrostatic pressure testing of a railroad car is also disclosed in which gravity flow evacuation of water through the hollow structural members is achieved by utilizing gravity flow of water throughout. In both the aforementioned assembly and method, water deterioration, corrosion, and the like after hydrostatic pressure testing are substantially minimized or totally eliminated.

BACKGROUND OF THE INVENTION 
This invention relates to internal water drainage of a hollow member 
structural assembly in a railroad pressure discharge hopper car or the 
like, including a method for drainage of the hollow member structural 
assembly after hydrostatic testing of the railroad car. 
Powdered, bulk commodities (i.e., flour, starch and talc) as oftentimes 
transported in pressure differential covered hopper cars. These cars are 
constructed to accommodate a predetermined internal pressure in order to 
allow pressure discharge unloading of the bulk commodity from within the 
railroad car. Fast and efficient unloading of the commodity to remote 
receiving bins of a customer is thus possible. For example, unloading 
rates of up to 100,000 pounds per hour may be achieved where the internal 
pressure of the car is operated at about 14.5 psi. This means that the 
hopper car must accommodate that amount of internal pressure (with an 
adequate safety factor) during unloading without causing damage to any of 
the structural components of the car. 
In order to verify the structural integrity of each such pressure discharge 
rail car manufactured, each such car is subjected a predetermined internal 
pressure. For such testing, hydrostatic pressure testing is used, 
following construction of the car. This method requires the hopper car to 
be filled with water and then to be pressurized to a predetermined 
pressure in order to verify the structural integrity of the railroad 
hopper car and its structural components. 
In some cases, such pressure discharge hopper cars are provided with a 
number of adjacent hoppers or compartments which are separated by 
compartment partition walls or bulkheads. These partition walls or 
bulkheads terminate short of the top or upper end of the hopper car in 
order to permit the powdered bulk commodities to fill up each compartment 
and then flow into an adjacent compartment through large openings between 
the top of the compartment walls or bulkheads and the top of the hopper 
car. Typically, interconnected hollow structural members are provided for 
internally supporting and reinforcing the compartment walls or the 
bulkheads relative to the elongated shell which forms the hopper car. 
Since these hollow structural members may not be airtight during pressure 
testing of the car, these hollow structural members oftentimes become 
filled with water during the hydrostatic pressure testing of the hopper 
car. While the water used in hydrostatic testing each of the railcars 
manufactured can be easily removed through bottom outlets associated with 
each compartment or hopper, it has been found that some residual water 
remains trapped in the interconnected hollow structural members. 
Unfortunately, this results in water deterioration and corrosion of the 
internal surfaces along the compartment walls or bulkheads and other 
internal surfaces within the compartments or hoppers. Also over time, this 
entrapped water, often having a high concentration of rust, seeps out of 
the hollow members and discolors the interior of the car and the lining 
and may partially contaminate a lading. Because customers demand purity in 
the powdered bulk commodities, any rust from the inside of the 
compartments, caused by water deterioration, can create substantial 
problems. Therefore, when residual water remains inside the interconnected 
hollow structural members and causes damage to inside surfaces of the 
hopper car, it is necessary to rework such surfaces and remove all 
corrosion and other debris. This often means that the lining for the car 
must be repaired. As can be appreciated, this is not only costly, but is a 
time consuming process requiring inspection and subsequent repair of any 
deteriorated surfaces in the hopper car. 
SUMMARY OF THE INVENTION 
Among the several objects and features of this invention may be noted: 
The provision of an internal water drainage system for an interconnected 
hollow structural assembly within a railroad hopper car or the like, in 
which the interconnected hollow structural assembly is constructed to 
provide internal water drainage therethrough for the ready evacuation of 
the water after hydrostatic testing and before lining the car; 
The provision of such an internal water drainage system which provides 
gravity flow evacuation of water from the hollow structural assembly; 
The provision of such an internal water drainage system which substantially 
minimizes and/or eliminates any subsequent water deterioration problems, 
as well as the time and expense of repairing such problems; and 
The provision of such an internal water drainage system which retains the 
structural integrity of the hollow structural assembly while affording 
water drainage throughout the assembly, which effectively utilizes gravity 
in removing water throughout the assembly, which is really incorporated in 
the design of such a railway car without substantial additional cost, 
which results in substantial labor savings during fabrication and lining 
of such a railway car, and which provides substantial economic savings by 
not requiring any subsequent repairing or resurfacing of the internal 
surfaces of the hopper car. 
Briefly stated, an internal water drainage system of the present invention 
for a hollow structural assembly may be used in a railroad car (or other 
such structure) having a shell. The hollow structural assembly includes 
interconnected hollow structural members for internal support of the shell 
or other structural members. At least one of the hollow structural members 
is positioned at least partially below another hollow structural member. A 
water draining passageway is formed in such hollow structural members in 
an area of juncture between the members, and a water drain opening is 
formed in the shell which communicates and cooperates with the water 
drainage passageway provided in the hollow structural members in order to 
facilitate gravity flow of water through the hollow structural members for 
evacuation and removal from the shell via the drain opening. In addition 
to the aforesaid internal water drainage hollow structural assembly, a 
method for hydrostatic pressure testing of a railroad car is disclosed 
which employs gravity flow evacuation of water from the shell of a 
railroad car including interconnected hollow structural members therein, 
by utilizing gravity flow removal of water throughout for evacuation from 
the tank car. Following removal of the water from the railroad car 
including the associated interconnected hollow structural members, the 
water draining openings in the tank car are sealed off. 
Other objects and features of this invention will become apparent from the 
ensuing description.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A pressure differential railroad hopper car 1, as shown in FIG. 1 of the 
drawings, is designed to handle powdered or other dry, fluent bulk 
commodities, such as flour, starch, talc and the like. Car 1 includes an 
undercarriage wheel structure 3 which rollingly supports an elongated and 
unitary car body or shell 5 on rails 6. Within the shell 5, there are a 
plurality of compartments or hoppers 7 which are separated from one 
another by generally vertically directed compartment partition walls or 
bulkheads 9. In FIG. 1, the bulkheads 9 are shown in broken lines and are 
connected at their lower ends to downwardly and inwardly tapering sloping 
walls or slope sheets 11 which converge toward an outlet opening 0 for 
unloading the contents for each hopper 7. Connected to each product 
discharge outlet opening 0 is a product discharge system 13 having a pipe 
or piping 15 connected to each of the hoppers 7 in order to allow internal 
pressurization of the car. Product discharge system 13 further includes a 
discharge pipe 16 connected to each outlet 0 for pneumatically conveying 
the lading from the car. Loading hatches 17 are provided on the car body 
roof are for loading a lading into the hoppers 7. When hatches 17 are 
closed, the lading is maintained in a dry and sanitary condition. Hatches 
17 are so constructed as to permit internal pressurization of car body 5. 
Unloading rates up to 100,000 pounds per hour may be achieved, depending on 
the type of commodity, and the length, size and configuration of the 
conveying lines. In order to achieve fast and efficient unloading from the 
hopper car 1, it is necessary that hopper car 1 be internally pressurized 
to a predetermined internal pressure without damage to the car. It has 
been found that unloading rates of up to 100,000 pounds per hour may be 
achieved where the car is operated at about 14.5 PSI. Other cars may be 
operated at lower or higher levels of internal pressurization. 
Hydrostatic pressure testing of the hopper car 1, after construction, is 
the typical method of establishing and verifying the predetermined 
internal pressure desired for the hopper car 1. The hopper car 1 is filled 
with water and pressurized to a predetermined level, e.g., 22.5 PSI, to 
determine the structural integrity of shell 5, as well any other 
structural components within the railroad car 1 which are subjected to 
this pressure loading. As will be discussed in detail below, bulkheads 9 
may be reinforced, as generally indicated at R, with interconnected hollow 
structural members (as will appear) at the upper end thereof for 
reinforcing and supporting the upper portions of bulkheads 9 proximate the 
roof of hopper car 1. 
Following hydrostatic pressure testing of the hopper car 1, the water is 
drained therefrom. However, since in normal operation, the hollow 
structural members may not be airtight, during hydrostatic testing, water 
may seep in to these hollow structural members and become entrapped 
therewithin. This entrapped water will, in many instances, cause the inner 
surfaces of the hollow structural members to rust or to otherwise corrode. 
The entrapped water may thus become laden with rust. If this rusty water 
leaks from within the hollow members (which it often does), it will stain, 
damage, or contaminate the inside of the car or the lading. It should also 
be realized that such testing is performed before painting and lining of 
the car. Oftentimes, this rusty water will leak out of the hollow members 
after painting or lining of the car and will be quite visible. This 
requires substantial reworking of the interior surfaces of the hopper car 
1 in order to remove all corrosion and other debris caused by water 
deterioration, and may require a costly repair of the lining or paint. The 
present invention is directed toward solving this problem in order to 
minimize or to substaintially eliminate the need for expensive and time 
consuming re-working or repair of the interior surfaces of the hopper car 
1. 
While, within the broad aspects of the present invention, the water 
drainage system and method of the present invention may be utilized in 
connection with interconnected hollow structural members used for any 
purpose, it is particularly useful in the fabrication of railroad cars or 
the like. 
Specifically, and as shown in FIGS. 2-6 of the drawings, the reinforcement 
system R of the present invention comprises an interconnected hollow 
structural members assembly 21 which is secured to the upper ends of at 
least certain of the bulkheads 9 and to the inner face of the car body 5 
roof proximate the upper ends of the bulkheads 9. While the shape and 
orientation of the interconnected hollow structural assembly 21 may be 
varied to suit the particulars required, in the illustrated and disclosed 
embodiment, as will presently be described, they preferably include 
generally vertically extending, generally horizontally extending, and 
generally curvilinearly extending hollow structural members. 
As best seen in FIG. 3 of the drawings, a curvilinear channel-shaped member 
23, which has a shape corresponding to the curvature of the roof of shell 
5, has its channel opening 25 positioned toward the roof. Since FIG. 3 
represents approximately one half of the interconnecting hollow structural 
member assembly 21, the curvilinear channel shaped member 23 extends 
equidistantly downwardly from the center line shown in FIG. 3 on opposite 
side of the shell. 
An opening 24 is provided in the upper central margin of partition sheet 9 
adjacent the roof. The inner connected hollow structural member assembly 
21 further includes a generally vertically oriented, hollow structural 
member 27 having a square tube configuration, as shown in FIG. 6 of the 
drawings. The upper end of the hollow structural member 27 is connected to 
channel member 23, with the channel opening 25 of the channel-shaped 
member 23 in communication with the interior 29 of the generally 
vertically oriented hollow structural member 27. Since the FIG. 3 
representation illustrates approximately one-half of the interconnected 
hollow structural member assembly 21, there is preferably provided a 
corresponding vertically oriented structural members 27 on opposite sides 
of the center line as shown in FIG. 3. 
The lower end of each generally vertically oriented hollow structural 
member 27 is attached to a generally horizontally extending hollow 
structural member 31. It is to be noted that the portions of bulkhead 9 
defining opening 24 extend through the horizontally extending hollow 
structural member 31 and the vertically oriented hollow structural member 
27. Further, the upper margins of partition sheet 9 abut the downwardly 
facing closed face of the curvilinear channel-shaped member 23, to provide 
a structurally integrated support or reinforcement for the bulkhead 9 in 
conjunction with the upper inner wall of shell 5. The area bounded by the 
spaced vertically oriented hollow structural members 27, the horizontally 
extending member 31 and the curvilinear channel-shaped member 23, at the 
top of each bulkhead 9, defines opening 24 through which a powdered bulk 
commodity (lading) can be transferred between the hoppers or compartments 
during the loading process. In this manner two or more hoppers 7 may be 
simultaneously loaded using a singe hatch 17. 
This just described interconnected hollow structural member assembly 21 is 
typically used in providing internal reinforcing support for bulkheads 9 
at the upper ends thereof and for the upper portion of shell 5. Such 
structure, when subjected to hydrostatic pressure testing, oftentimes 
allows water to run (leak) into the channel opening 25 of the 
channel-shaped member 23 and into the interior 29 of the hollow structural 
members 27 and 31. Following the hydrostatic pressure testing, the water 
within the hopper car 1 can be removed from the hoppers, by way of the 
sloping surfaces or sheets 11 through the discharge outlets (not shown). 
However, some water may remain trapped within the hollow structural member 
assembly 21 and may not begin to leak from the hollow members for some 
time after hydrostatic testing. 
In accordance with the present invention, appropriately placed water 
draining passageways P may be are provided in the interconnected hollow 
structural member assembly 21 for communication with a water drain opening 
DO (see FIG. 3) provided in shell 5 at an appropriate location for the 
prompt and substantially complete draining of such entrapped water from 
within the hollow members of assembly 21. Specifically, it will be seen 
that the channel opening 25 of the channel-shaped member 23 is in 
communication with the interior 29, as indicated at 33, of the vertically 
oriented hollow structural member 27 so that water may readily be drained 
therefrom after hydrostatic pressure testing. In order to enable water to 
be removed following the hydrostatic pressure testing, internal water 
draining passageways 41 are provided in the areas of juncture between the 
generally vertically oriented hollow structural member 27 and the 
horizontally extending hollow structural member 31, as best seen in FIGS. 
4 and 5 of the drawings. A water draining passageway 41 is located on each 
side of bulkhead 9 which extends substantially upwardly throughout the 
entire extent of the horizontally extending hollow structural member 31, 
and at least partially through the vertically extending hollow structural 
member 27 thereby to permit water to drain from curvilinear member 23 and 
vertical structural member 27 into the lower positioned horizontally 
extending hollow structural member 31. 
At opposite ends of the horizontally extending hollow structure member 31, 
in the area of juncture with the channel-shaped member 23, at least along 
the lowermost extent thereof, internal water draining passageways 43 are 
provided in order to allow water to flow from the horizontally extending 
hollow structural member 31 into that portion of the channel-shaped member 
23 which is positioned therebelow, as shown in FIG. 3. Water is thus able 
to drain from the channel-shaped member 23 through a water drain opening 
DO provided in the elongated shell 5, adjacent the lower juncture with the 
channel-shaped member 23. 
Thus, gravity flow evacuation of water from within the interconnected 
hollow structural member assembly 21 is made possible by the water 
draining passageways 41 between the vertically oriented and horizontally 
extending hollow structural members 27, 31, respectively, and the water 
draining passageways 43 at the opposite ends of horizontally extending 
member 31 in the area of juncture with the channel-shaped member 23. From 
there, the water is drained out of the interconnected hollow structural 
member assembly 21 through the water drain opening DO in the elongated 
shell 5. Drain opening DO is preferably a threaded opening 45 in shell 5 
in communication with the lowermost reaches of channel opening 25 of 
channel 23. A drain plug 47 is threaded into water drain opening 45 to 
seal off the aforesaid openings and passageways after entrapped water is 
drained therefrom so as to ensure that shell 5 is leak free. 
The hydrostatic pressure testing method of the present invention, as herein 
described, permits filling the elongated shell 5 with water and 
pressurized to a predetermined pressure level (e.g., 22.5 PSI) so as to 
verify the structural integrity of the car, and then enables gravity flow 
evacuation of water from the elongated shell 5 including any water that 
may have entered the interconnected hollow structural assembly 23 or the 
like. Following removal of the water, the water drain openings 45 in the 
elongated shell 5 may be sealed off by the insertion of plugs 47 to 
prevent leakage from the car during internal pressurization. 
By removing all or substantially all of the water from the interconnected 
hollow structural member assembly 21, entrappment of substantial 
quantities of water within the hollow members is eliminated (or 
substaintially reduced), and substantial savings in both time and 
materials to repair and/or rework the inside surfaces of the elongated 
shell 5 are realized. 
As heretofore noted, the hollow members of assembly 21 may not be water 
tight. It is, however, preferred that such hollow members be water tight 
or seal so that lading particles or the like are prevented from 
accumulating therein inasmuch as these accumulated particles may lead to 
contamination of a lading or require expensive cleaning procedures. In 
accordance with this invention, if upon removing plugs 47 after 
hydrostatic testing water is found in assembly 21, air under pressure may 
be introduced into hollow assembly 21 via opening 45 and a bubble solution 
may be applied to the welds and joints of assembly 21 so as to aid in 
locating any air leak and to permit the ready sealing of such leaks, as by 
welding them closed. 
In view of the above, it will be seen that the several objects of the 
invention are achieved, and other advantageous results are obtained. 
As various changes could be made in the above constructions and methods 
without departing from the scope of the invention, it is intended that all 
matter contained the above description are shown in the accompanying 
drawings shall be interpreted as illustrative and not in a limiting sense.