Tube protection devices and methods

A tube protector device includes a first cap member, the first cap member being configured to fit over and substantially seal a first end of a tube; a second cap member, the second cap member being configured to fit over and substantially seal a second end of the tube; and a fastening device adapted to resiliently bias the first cap member toward the second cap member. At least the first cap member includes a collar configured to surround a portion of an outer surface of the tube and an angled tube support member configured to fit within the internal diameter of the tube, the collar and the angled support being configured to receive the first end of the tube therebetween. The first cap member further includes a sealing member, a particle barrier and/or a shock absorber between the collar and the angled support member. The tube protector may be used to protect, for example, quartz vacuum tubes from being contaminated by particulate matter, as well as from scratches and chips that may form in its surface during insertion and withdrawal from e.g., semiconductor manufacturing equipment, such as diffusion furnaces.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to tube protection devices and methods. More 
particularly, the present invention relates to devices and methods to 
protect vacuum tubes, such as diffusion furnace tubes used in 
semiconductor manufacturing equipment, during their installation in and 
removal from diffusion furnaces, and the like. 
2. Description of the Related Art 
Conventionally, diffusion furnace vacuum tubes are installed by sliding the 
unprotected tube through a particulate laden vestibule block and onto and 
through the heating elements of the furnace, and then though another 
vestibule block. However, as the tube is slid through the vestibule blocks 
of the furnace, the edge of the tube tends to shave particles off the 
blocks, which particles collect within and around the vacuum tube. As the 
vacuum tube must be maintained in as pristine a state as possible during 
installation, the particles shaved from the vestibule blocks necessarily 
degrade the performance of the tube. 
However, the vestibule blocks are not the only source of undesirable 
particulate matter within and around the tubes. Indeed, the heating 
elements of the diffusion furnace are also a contaminant source. The 
heating element coils of the diffusion furnace are separated by 
insulators. Once the tube has been inserted through the first vestibule 
block, it must slide past the heating element coils. As the tube is slid 
through the heating element coils of the furnace, its sealing surface is 
pushed, shoved, dragged and scrapped across the insulators of the heating 
elements. This pushing, shoving, dragging and scrapping across the 
insulators of the heating elements scratches and may actually chip the 
vacuum tube. Such scratches and chips may and often do cause undesirable 
vacuum leaks. 
Therefore, the tube accumulates particles and other contaminants as it 
passes through the first vestibule block, may acquire scrapes or chips as 
it is dragged past the heating coil insulators, and accumulates additional 
contaminants and particulate matter as it is slid past the second 
vestibule block. Such scratches, chips and particle contamination degrade 
the performance of the tube, and cause vacuum leaks. When such 
contamination or damage to the tube occurs, the tube must be removed, 
cleaned and repaired, if possible. Such damage may lead to failed product 
runs, costly down time and the immobilization of a furnace or production 
line until a replacement tube can be found and installed without excessive 
damage thereto. 
When the tube is removed from the diffusion furnace, the above-described 
steps are performed in reverse order. However, since the tube is now 
pulled back through the second vestibule block, the tube occasionally 
slips out too quickly and drops onto the heating element. As the 
vestibule's internal diameter is smaller than the internal diameter of the 
heating elements, they are now on the same plane. Such a drop may, and 
frequently does, result in a broken tube. Such broken tubes must 
thereafter be replaced, again immobilizing the furnace, and possibly the 
entire line until a replacement tube can be located and installed. 
Moreover, such tubes are costly to replace, both in terms of the value of 
the tube itself as well as in terms of unproductive down time. 
There has been a long felt need, therefore, for devices and methods of 
protecting such tubes during insertion into and withdrawal from furnaces. 
In particular, what is needed is a device and a method to prevent 
particulate matter from contaminating interior and exterior surfaces of 
such tubes during installation. What is also needed is a device and a 
method to prevent such tubes from becoming scratched and chipped as they 
are inserted through and removed from the furnace, past the heating and 
other internal elements of the furnace. 
SUMMARY OF THE INVENTION 
It is, therefore, an object of the present invention to provide devices and 
methods of protecting such tubes during insertion into and withdrawal from 
furnaces. In particular, it is an object of the present invention to 
provide devices and methods of preventing particulate and other foreign 
matter from contaminating interior and exterior surfaces of such tubes 
during installation and removal thereof. It is a further object of the 
present invention to provide devices and methods to prevent such tubes 
from becoming scratched and chipped as they are inserted through the 
furnace, past the heating and other internal elements of the furnace. 
In accordance with the above-described objects and those that will be 
mentioned and will become apparent below, a tube protector device, 
according to an embodiment of the present invention, comprises: 
a first cap member, the first cap member being configured to fit over and 
substantially seal a first end of a tube; 
a second cap member, the second cap member being configured to fit over and 
substantially seal a second end of the tube; and 
a fastening device adapted to resiliently bias the first cap member toward 
the second cap member. 
According to other illustrative embodiments, the first cap member may 
include a collar configured to surround a portion of an outer surface of 
the tube and an angled tube support member configured to fit within an 
internal diameter of the tube, the collar and the angled support being 
configured to receive the first end of the tube therebetween. The first 
cap member may further comprise a sealing member, a particle barrier 
and/or a shock absorber between the collar and the angled support member. 
The sealing member may include one or more O-rings. 
Similarly, the second cap member may include a collar configured to 
surround a portion of an outer surface of the tube and an angled tube 
support member configured to fit within an internal diameter of the tube, 
the collar and the angled support being configured to receive the second 
end of the tube therebetween. The second cap member may further comprise a 
sealing member, a particle barrier and/or a shock absorber between the 
collar and the angled support member. The sealing member may include one 
or more O-rings. 
According to still further embodiments, the second cap member may comprise 
a substantially flat plate. The substantially flat plate may include a 
sealing member, a particle barrier and/or a shock absorber mounted 
thereon. The flat plate may include one or more O-rings mounted thereon. 
One or both of the first and second caps may include a centrally disposed 
hook to which the fastening device is attachable. The fastening device, 
for example, may include a rubber band or other resilient device. The 
fastening device, in use, may be stretched within the interior of the 
tube. 
The present invention may also be viewed as a method of protecting a tube, 
comprising the steps of: 
placing a first protective cap over a first end of the tube; 
attaching a resilient fastening device to the first protective cap; 
stretching the fastening device and attaching the fastening device to a 
second protective cap configured to fit over a second end of the tube; and 
releasing tension on the fastening device and covering the second end of 
the tube with the second protective cap. 
According to other preferred embodiments, one or both of the first and 
second protective caps may include an O-ring mounted therein and the 
method further may comprise the step of selecting the size of the O-ring 
according to the size of the tube. The stretching step may include a step 
of inserting a hook rod into the tube to catch the fastening device and 
retracting the rod to stretch the fastening device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The structure of the present tube protector device and method will be 
described with reference to FIGS. 1 through 7. The tube protector device 
according to the present invention includes a first cap member 110. The 
first cap member 110 is configured to fit over and substantially seal a 
first end of a tube, such as, for example, a quartz vacuum tube 170 of a 
diffusion furnace for a semiconductor manufacturing operation. A second 
cap member 120 (shown in FIG. 6) is disposed on the second end of the tube 
170. A fastening device 150 (FIGS. 4 and 6) is attached to both the first 
and the second cap members 110, 120 and resiliently biases the first cap 
member 110 toward the second cap member 120. When the first and second 
caps 110, 120 are in place on the first and second ends, respectively, of 
the tube 170, the tube 170 may be inserted through the furnace vestibule 
and slid past the heating elements of the furnace and through the second 
vestibule without gathering particulate matter or other contaminants 
inside the tube 170 and without being scratched or chipped. 
The first cap member 110 may include a collar 145 configured to surround a 
portion of an outer surface of the tube 170. As shown in FIG. 1, the first 
cap 110 may also include an angled tube support 125 configured to fit 
within the inner diameter of the tube 170, the collar 145 and the angled 
support 125 being configured to receive the first end of the tube 170 
therebetween. The angled tube support 125 may form, for example, an angle 
of about 75 degrees with respect to the surface of the first cap member 
110 that is perpendicular to the longitudinal axis of cap member. Also as 
shown in FIG. 1, the first cap member 110 may include a sealing member, a 
particle barrier and/or a shock absorber 175 between the collar 145 and 
the angled tube support 125. This sealing member, particle barrier and/or 
shock absorber 175 may be, as shown in FIG. 1, an O-ring sized to the tube 
170 to be protected. 
The second cap member 120 may be similar to the first cap member 110, or 
may have a structure that differs from that of the first cap member 110. 
For example, if the tube 170 includes a smaller end, as shown in FIG. 6, 
the second cap member 120 may include a substantially flat plate 120 
(shown in FIG. 5) configured to fit over the smaller end of the tube 170. 
The substantially flat plate 120 may also include a sealing member, a 
particle barrier and/or a shock absorber similar to that referenced by 
numeral 175 mounted thereon. Such a sealing member, a particle barrier 
and/or a shock absorber may include an O-ring. The first and second caps 
110, 120 each may include a centrally disposed hook 140 to which the 
fastening device 150 may be attached. The hook 140 may be a hooked bolt 
and may be attached to the first and second cap members 110, 120 along 
with a washer and nut assembly 135, 142, as shown in FIGS. 1, and 3. A 
handle 130 facilitates placement and removal of the first cap member 110 
onto the first end of the tube 170. The fastening device 150 may include a 
rubber band, as shown in FIG. 4. 
The present invention prevents expensive tubes, such as quartz tubes used 
in conjunction with semiconductor diffusion chambers, from being scratched 
to the point of failure, chipped beyond use and needlessly contaminated by 
particulate matter. The device according to the present invention provides 
caps to seal over the sealing surface and large open end of such tubes as 
they are installed into and removed from diffusion furnaces and/or other 
devices and machines. Thanks to the present invention, the sealing surface 
of such tubes is protected from scratches, chips and breakage and prevents 
the clean tube from being soiled prior to its insertion into the heating 
system or other machine. The device may be installed in a few minutes 
(e.g., about 3) and has the potential of saving a great deal of money, 
maintenance efforts and down time. The tube protector device, moreover, 
may be constructed in various sizes to enable its use with most any tube 
used for most any purpose. For example, the tube protector device 
according to the present invention may also be advantageously used to 
protect the tube 170 during shipping thereof. 
To use the tube protector according to the present invention, the hook rod 
155 is equipped with a sufficient number of extension rod units 160, and 
passed through, e.g., the second or small end of the tube 170. An O-ring 
175 of a suitable size for the tube 170 being used may then be placed 
inside the first cap member 110, as shown in FIG. 1. The O-ring 175 acts 
as a particle barrier, a sealing member and a shock absorber between the 
collar 145 of the first cap member 110 and the angled tube support 125. 
Next, one end of the fastening device 150, which may be, for example, a 
thick rubber band, is attached to the hook 140. The other end of the 
fastening device 150 is then hooked onto the hook rod 155. The loose 
excess portion of the fastening device 150 is then placed inside the tube 
170. The first cap member 110 is then gently placed over the first end of 
the tube 170. The hook rod 155 (with all necessary extension rods 160) and 
the fastening device 150 are then pulled through the second (e.g., small) 
end of the tube 170. Once the rod 155, 160 has cleared the second end of 
the tube 170, the fastening device 150 is removed from the hook rod 155, 
160 and the second cap member 120 (e.g. substantially flat plate) is 
attached to the fastening device 150. Releasing the tension on the 
fastening device 150, the second cap member 120 is gently disposed over 
and on the second (e.g., small) end of the tube 170. The tube protector 
device is now installed on the tube 170. 
To install the tube and protector device assembly into the manufacturing 
equipment (e.g., a diffusion furnace, not shown), the first and second 
ends of the tube 170 are cleaned, to remove any contaminants that may have 
accumulated thereon during the above-described installation procedure. The 
tube 170 and protector device assembly is then inserted into the furnace 
and the second cap member 120 is removed from the second end of the tube 
170. The hook rod 155, 160 is then re-attached to the fastening device 150 
and extended into the tube 170, up to the first cap member 110. The first 
cap member 110 is then removed from the tube 170 and the fastening member 
150 removed from the hook rod 155, 160. The hook rod 155,160 is then 
removed from within the tube 170. In this manner, a clean, scratch and 
chip free tube 170 has been installed into the furnace. When removing the 
tube 170 from the furnace, the above-detailed steps may be carried out in 
reverse order to remove the tube without damage or contamination. 
The tube protector device according to the present invention may be made of 
any hard and rigid material, such as steel, plastics, carbon fiber 
composites, etc. 
While those of skill in this art will readily recognize that the tube 
protection device disclosed herewith may be scaled to various dimensions, 
the following illustrative approximate dimensions of the constituent 
components of the inventive device are given. However, it is to be 
understood that the following approximate preferred, lower and upper 
dimensions are given only for illustrative purposes and to disclose the 
relative dimensions of the constituent elements. The present invention, 
therefore, should in no way be considered to be limited to the dimensions 
given herewith. 
TABLE 1 
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Dimensions for FIG. 1 
Dimension 
reference Preferred Lower Upper 
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D111 6" 2.5" 15" 
D112 1" 0.25" 1.5" 
D113 11/2" 0.375 2" 
D114 20 angle 0 angle 60 angle 
D115/117 75 angle 15 angle 85 angle 
D116 9.3" 4.2" 20" 
D118 4" 1" 10" 
D119 1/2" 0.125" 2" 
D120 3/4" 1/16" 1" 
D121 15" 3.5" 60" 
D122 4" 1" 16" 
D123 1/8" 1/32" 1/2" 
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TABLE 2 
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Dimensions for FIG. 2 
Dimension 
reference Preferred Lower Upper 
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D211 9.55" 2.5" 30" 
D212 6" 1.5" 24" 
D213 3" 0.75" 12" 
D214 1/4" 1/16" 1" 
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TABLE 3 
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Dimensions for FIG. 3 
Dimension 
reference Preferred Lower Upper 
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D311 75 15 85 
D312 1/8" 1/32" 1/2" 
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TABLE 4 
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Dimensions for FIG. 5 
Dimension 
reference Preferred Lower Upper 
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D511 3/8" 3/32" 1.5" 
D512 6" 1.5" 24" 
D513 5" 1.25 20" 
D514 1" 1/4" 4" 
D515 1/2" 1/8" 2" 
D516 3 ft. 9" 12 ft. 
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While the foregoing detailed description has described preferred 
embodiments of the present invention, it is to be understood that the 
above description is illustrative only and not limiting of the disclosed 
invention. For example, the dimensions given may vary from the 
illustrative examples given. Details in the structure of the protector 
device may be varied without, however, departing from the present 
invention as defined by the claims. The tube protector may be made of 
materials other than those specifically disclosed without, however, 
departing from the scope and spirit of the present invention. Thus, the 
present invention to be limited only by the claims as set forth below.