U.S. patent application number 09/776468 was filed with the patent office on 2002-08-08 for controlled slow descent bailer.
Invention is credited to Pratt, David W..
Application Number | 20020104648 09/776468 |
Document ID | / |
Family ID | 25107456 |
Filed Date | 2002-08-08 |
United States Patent
Application |
20020104648 |
Kind Code |
A1 |
Pratt, David W. |
August 8, 2002 |
CONTROLLED SLOW DESCENT BAILER
Abstract
A bailer having a slow rate of descent into a liquid body to
minimize agitation. In a first embodiment, a plug closes the upper
end of the bailer and a perforation is formed in the plug. Air in
the hollow interior of the tubular main body of the bailer is
constrained to flow through the perforation as the bailer fills. A
back pressure created by the air prevents rapid descent of the
bailer and thus prevents rapid filling of the bailer. When the
bailer is being emptied, the perforation prevents a vacuum from
forming in the space below the plug and above the liquid level, but
it provides a partial vacuum and therefore slows down the rate of
flow of the liquid as it exits the bailer. Covering the perforation
with a thumb creates a vacuum above the liquid level and stops the
flow of liquid from the bailer. This eliminates the need for a tool
that unseats the valve of the bailer from its valve seat. In
another embodiment, the perforation is eliminated and rings are
secured to the tubular main body of the bailer to slow its rate of
descent. Additional embodiments include a baffle wall for slowing
bailer descent and a stabilizer tube at the lowermost end of the
bailer for maintaining the bailer in an upright configuration
during its descent.
Inventors: |
Pratt, David W.;
(Clearwater, FL) |
Correspondence
Address: |
SMITH & HOPEN PA
15950 BAY VISTA DRIVE
SUITE 220
CLEARWATER
FL
33760
|
Family ID: |
25107456 |
Appl. No.: |
09/776468 |
Filed: |
February 2, 2001 |
Current U.S.
Class: |
166/165 ;
166/168 |
Current CPC
Class: |
E21B 49/082 20130101;
G01N 1/12 20130101 |
Class at
Publication: |
166/165 ;
166/168 |
International
Class: |
E21B 027/00 |
Claims
What is claimed is:
1. A bailer, comprising: an elongate, tubular main body having a
hollow interior; said elongate, tubular main body having an open
upper end and a lower end; a plug for closing said open upper end;
a perforation of predetermined size formed in said plug; a check
ball and a check ball seat disposed at said lower end of said
bailer, said check ball lifting from said check ball seat, when
said bailer is lowered into a body of liquid fluid, in response to
an inflow of liquid fluid into said hollow interior; said open
lower end having a diameter substantially larger than a diameter of
said perforation; whereby air in said hollow interior is
constrained to flow out of said hollow interior through said
perforation as said liquid fluid flows into said hollow interior;
whereby a back pressure is created by said air because said air
cannot flow through said perforation at a rate of flow that exceeds
the rate of flow of said liquid fluid into said hollow interior;
whereby liquid fluid flows slowly into said hollow interior;
whereby said bailer descends into said liquid body at a slow rate
of speed; and whereby agitation of said liquid fluid is
reduced.
2. The bailer of claim 1, further comprising: a boss means formed
on said plug; a throughbore formed in said boss means; and said
throughbore being in open fluid communication with said
perforation.
3. The bailer of claim 1, further comprising; a first weight means
secured to said elongate, tubular main body near a lowermost end
thereof.
4. The bailer of claim 3, further comprising: a second weight means
secured to said elongate, tubular main body near an uppermost end
thereof.
5. The bailer of claim of claim 3, wherein said perforation has a
diameter between about 0.030 to 0.10 inches.
6. A bailer, comprising: an elongate, tubular main body having a
hollow interior; said elongate, tubular main body having an open
upper end and a lower end; a check ball and a check ball seat
disposed at a lower end of said bailer, said check ball lifting
from said check ball seat, when said bailer is lowered into a body
of liquid fluid, in response to an inflow of liquid fluid into said
hollow interior; at least one annular baffle wall mounted to an
external wall of said elongate, tubular member at a preselected
location thereon; whereby said bailer descends into said liquid
body at a slow rate of speed; whereby liquid fluid flows slowly
into said hollow interior; whereby agitation of said liquid fluid
is reduced.
7. The bailer of claim 6, wherein said at least one annular baffle
wall is flat, extending radially outwardly from said external wall
in normal relation thereto.
8. The bailer of claim 7, wherein said annular baffle wall includes
a downwardly opening concavity.
9. The bailer of claim 1, further comprising a tubular stabilizer
secured to said lower end of said elongate main body, said tubular
stabilizer extending in leading relation to said lower end.
10. The bailer of claim 6, further comprising a tubular stabilizer
secured to said lower end of said elongate main body, said tubular
stabilizer extending in leading relation to said lower end.
11. The bailer of claim 6, further comprising: a plug for closing
said open upper end; and a perforation of predetermined size formed
in said plug; whereby air in said hollow interior is constrained to
flow out of said hollow interior through said perforation as said
liquid fluid flows into said hollow interior; whereby a back
pressure is created by said air because said air cannot flow
through said perforation at a rate of flow that exceeds the rate of
flow of said liquid fluid into said hollow interior.
12. The bailer of claim 11, wherein said at least one annular
baffle wall is flat, extending radially outwardly from said
external wall in normal relation thereto.
13. The bailer of claim 12, wherein said annular baffle wall
includes a downwardly opening concavity.
14. The bailer of claim 11, further comprising: a boss means formed
on said plug; a throughbore formed in said boss means; and said
throughbore being in open fluid communication with said
perforation.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates, generally, to bailers. More
particularly, it relates to a bailer having a construction that
controls and slows the rate of descent of the bailer into a liquid
fluid to a speed sufficiently slow to substantially avoid agitation
of the liquid fluid from which a sample is being taken.
[0003] 2. Description of the Prior Art
[0004] One of the problems confronting the bailer industry is the
speed with which samples are normally taken. The people in the
field who take samples from wells or other bodies of liquid are
generally interested in taking as many samples per day as possible.
Accordingly, many developments in the industry have been designed
to increase the speed of bailer insertion into a well. For example,
there are a number of bailer designs that add weights to a bailer
to increase its insertion speed. Unfortunately, this also increases
the agitation of the liquid.
[0005] Moreover, various environmental protection agencies at the
state level are reporting an unacceptably high rate of bad sample
data attributed largely to the speed of sample collection.
Apparently, a fast-traveling bailer increases agitation and causes
turbidity by stirring up sediment and the like that would remain
undisturbed if the bailer were entering into and traveling through
the liquid fluid at a slower rate. Thus, pollutants are collected
that would not have been collected if the bailer had descended and
filled at a slower rate. Agitation can also increase the oxygen
content of the liquid, thereby generating false data.
[0006] There are two relatively obvious solutions to the problem.
The first solution, not favored by state agencies, is to provide
better training to those who work with bailers in the field so that
they will collect the samples at a slower rate. The time and
expense that would be required to educate such workers is thought
to be prohibitive. Nor do such agencies trust the efficacy of such
training.
[0007] The second solution, favored by some experts in the field
and some governmental authorities, is to ban the use of bailers and
to mandate that pumps be employed to collect samples. There are
several problems with that solution. Most importantly, perhaps, is
the fact that pumps have moving parts capable of stirring up
sediment and their use will therefore not solve the agitation and
turbidity problems. Moreover, pumps are much more expensive than
bailers. A disposable bailer may cost no more than a few dollars
but a pumping system can cost from fifteen hundred dollars to
triple that amount. It follows that pumps of such expense cannot be
used one time and discarded as are bailers. Instead, to avoid
cross-contamination between various wells, a pumping system must be
thoroughly cleaned after each use. This consumes large quantities
of pure water and time.
[0008] It has also been proposed that to avoid the cross
contamination problem and the time and expense of cleaning a pump
after each use, a pump could be permanently installed at each
sample collection site, such as a well. This solution is
impractical in view of the extremely large number of collection
sites. For example, there may be a hundred wells just in one small
area near a known source of contamination.
[0009] Moreover, pumps require electrical power which is often
unavailable in remote collection sites. A portable generator would
have to be brought to such locations, thereby driving up the cost
of sample collection even higher.
[0010] Pumps, then, are clearly not the answer to the problem.
[0011] In view of the prior art, considered as a whole, at the time
the present invention was made, it was not obvious to those of
ordinary skill in the pertinent arts how the problems associated
with poor samples based upon excessive bailer speed insertion could
be resolved.
SUMMARY OF THE INVENTION
[0012] The longstanding but heretofore unfulfilled need for a
bailer that descends slowly into a body of liquid and which fills
slowly to reduce agitation is now met by a new, useful, and
nonobvious invention. The novel bailer includes an elongate,
tubular main body having a hollow interior and having an open upper
end. A plug closes said upper end and a small perforation of
predetermined size is formed in the plug. A check ball and a check
ball seat are disposed at a lower end of the bailer and the check
ball lifts from the check ball seat when the bailer is lowered into
a body of liquid fluid, in response to an inflow of liquid fluid
into the elongate, tubular main body. In this way, air positioned
below the plug and above the liquid fluid is constrained to flow
out of the elongate, tubular main body through the perforation as
liquid fluid flows into the elongate, tubular main body.
Accordingly, a back pressure is created by the air because the air
cannot flow through the perforation at a rate of flow that exceeds
the rate of flow of the liquid fluid into the elongate, tubular
main body. Thus, the bailer descends slowly into the liquid fluid
and the liquid fluid flows slowly into the elongate, tubular main
body and agitation of the liquid fluid is reduced.
[0013] When the bailer is being emptied, the presence of the plug
and the small perforation creates a near vacuum in the space below
the plug and above the liquid level because ambient air cannot flow
through the perforation into the space as quickly as the liquid
fluid can flow from the bailer. This near vacuum thus provides a
braking action that prevents rapid outflow of the liquid sample,
again reducing agitation.
[0014] In a first embodiment, the perforation is formed in the plug
and in a boss means that projects upwardly therefrom. The
perforation is perhaps more accurately described as a throughbore
in that it extends through the boss means and the plug. In a second
embodiment, the boss means is eliminated and the throughbore is
formed in the plug only.
[0015] In a third embodiment, one or more flat baffle walls are
mounted to the external wall of the elongate, tubular main body to
slow the rate of descent of the bailer. The plug and the
perforation formed therein may be eliminated so that the elongate,
main tubular body is open at its uppermost end or the plug and
perforation formed therein may be maintained and used in
conjunction with the baffle wall.
[0016] In a fourth embodiment, the baffle wall defines a downwardly
opening cavity.
[0017] A fifth embodiment includes a stabilizer means in the form
of a hollow tube that is secured to the lowermost end of the bailer
in leading relation thereto.
[0018] A primary object of the invention is to provide a bailer
that descends slowly into a body of liquid fluid to reduce
agitation and turbidity.
[0019] A closely related object is to provide such a bailer that
does not require training or educating workers in the field as to
their proper use.
[0020] Another object is to provide a bailer which may also be
emptied slowly.
[0021] These and other important objects, advantages, and features
of the invention will become clear as this description
proceeds.
[0022] The invention accordingly comprises the features of
construction, combination of elements, and arrangement of parts
that will be exemplified in the description set forth hereinafter
and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] For a fuller understanding of the nature and objects of the
invention, reference should be made to the following detailed
description, taken in connection with the accompanying drawings, in
which:
[0024] FIG. 1 is a side elevational view of a first embodiment of
the novel bailer;
[0025] FIG. 1A is a top plan view thereof;
[0026] FIG. 2 is a side elevational view of a second embodiment of
the novel bailer;
[0027] FIG. 2A is top plan view of said second embodiment;
[0028] FIG. 3 is a side elevational view of a third embodiment;
[0029] FIG. 3A is top plan view of said third embodiment;
[0030] FIG. 3B is a bottom plan view of said third embodiment;
[0031] FIG. 4 is a side elevational view of a fourth
embodiment;
[0032] FIG. 4A is a top plan view of said fourth embodiment;
[0033] FIG. 4B is a bottom plan view of said fourth embodiment;
[0034] FIG. 5 is a side elevational view of a fifth embodiment;
and
[0035] FIG. 5A is a bottom plan view of said fifth embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] Referring to FIGS. 1 and 1A, it will there be seen that the
reference numeral 10 denotes an illustrative embodiment of the
present invention. It should be understood from the outset that the
invention to be disclosed has utility with bailers of all types and
sizes. The bailer denoted 10 is merely one type of bailer and the
invention is not restricted to bailers of the type depicted. Bailer
10 includes a handle 12 at its uppermost end to which is secured a
rope, not depicted, or other suitable connection means to enable
the lowering and lifting of a bailer into and from a liquid body. A
weight housing 14 is slidingly received within tubular main body 16
of the bailer and provides a means for holding top weight members,
collectively denoted 18. A spider assembly 20 is positioned near
the lower end of tubular main body 16 and serves to guide
hemispherical valve body 22, known in the industry as a check ball,
as it rises and falls with respect to valve seat 24. Valve stem 26
is slidingly received within an aperture formed in the center of
spider assembly 20 so that check ball 22 rises and separates from
check ball seat 24 when liquid fluid flows into the hollow interior
of tubular main body 16 and so that said check ball returns to its
seated position against said check ball seat 24 when said liquid
fluid has ceased flowing into said tubular main body. A lower set
of weights, collectively denoted 28, is provided near the lowermost
end of bailer 10. A tubular fluid entry/discharge downspout 30
depends from check ball seat 24.
[0037] As perhaps best understood in connection with FIG. 1A, the
uppermost end of weight housing 14 (or the uppermost end of tubular
main body 16 if said weight housing is not provided), is closed
with a plug 32 having a vent opening or perforation 34 formed
therethrough. In this particular embodiment, vent opening 34 is
formed in a boss 36 that is formed integrally with plug 32. In an
illustrative embodiment of the invention, perforation 34 is formed
by a needle or pin of common size and has a diameter of about 0.060
inch. The range of diameters is from about 0.030 inch to about 0.10
inch. This diameter of perforation 34, when used in connection with
a one (1) liter bailer having two ounces (2 oz.) of weights and
having a downspout 30 that is 0.730 inches in diameter, results in
a fill rate of about fifty seconds. It follows that the same
opening in a half liter bailer of the same size and similarly
weighted would produce a fill time of about twenty five
seconds.
[0038] There are three primary factors that influence how fast
bailer 10 will fill: 1) the diameter of downspout 30; 2) the
combined mass of weights 18 and 28, and the diameter of perforation
34. Based upon the perforation and downspout sizes and weights
disclosed herein, the optimal size of perforations for bailers
having differing weights and downspouts of differing sizes may be
empirically determined.
[0039] Another problem in the bailer industry is caused by the
rapid emptying of bailers after a sample has been collected. A
too-rapid emptying can also create agitation in the sample, thereby
skewing laboratory test results. It has been observed that the
provision of perforation 34 slows the emptying flow rate by about
twenty five per cent (25%), thereby further alleviating the
agitation problem.
[0040] Another advantage of the novel structure is its reduction of
a need for a VOC device (not depicted). Such devices are used in
the industry to momentarily unseat a valve such as check ball 22
from check ball seat 24 when the sample is being deposited into a
plurality of vials. For example, where the collected sample is to
be distributed into ten (10) vials, a VOC is used to momentarily
lift check ball 22 from seat 24 to enable about one tenth
({fraction (1/10)}.sup.th) of the sample to flow from the bailer
into a first vial. The process is then repeated until all vials
have been filled.
[0041] Provision of perforation 34 reduces the need for a VOC,
especially in those cases where the bailer is less than half
filled. In such a case, the bailer user merely covers perforation
34 with a thumb until downspout 30 is in proper alignment with the
mouth of a vial. This creates a vacuum in the space below the
perforation and above the liquid level. The thumb is then lifted
and the desired amount of sample is allowed to flow into the vial.
Perforation 34 is then covered again and the process is repeated.
This not only eliminates the need for a VOC when the bailer is
about half full or less, it also prevents contamination of the
sample as often happens when a VCO is used and the sample contacts
the user's hand as it flows out of the bailer into the vial.
[0042] When the bailer is more than half full, closing perforation
34 with a thumb will slow the flow rate of the liquid from the
bailer but may not stop it. In such cases, a VOC may still be
used.
[0043] FIG. 2 and FIG. 2A are like FIGS. 1 and 1A with the
exception that boss 36 is eliminated and perforation 34 is formed
in plug 32 only. The use of boss 36 is preferred because it helps
the user locate perforation 34.
[0044] FIGS. 3, 3A, and 3B depict a third embodiment. At least one
baffle wall 40 is secured to tubular main body 16 by suitable means
to provide a braking means that prevents rapid sinking and thus
rapid filling of the bailer. Baffle wall 40 could have a flat
profile as depicted in FIG. 3, where it extends radially outwardly
from the external wall of tubular main body 16 in normal relation
thereto, or it could have a parachute profile 42, including a
downward facing concavity 44, as depicted in FIGS. 4, 4A, and 4B,
for example. The rate of descent is affected by the amount of
weights 18, 28, as in the earlier embodiments, as well as the
diameter and number of rings and their shape. Empirical testing
would be required to determine optimal ring diameters and shapes to
achieve various desired rates of descent. In both the third and
fourth embodiments, the baffle wall or walls may be used with or
without plug 32 and perforation 34.
[0045] FIGS. 5 and 5A depict a fifth embodiment where a tubular
stabilizer 46 is secured by suitable means to a lower end of bailer
main body 16, in leading relation thereto. Stabilizer 44 must fill
with liquid before check ball 22 is unseated. This structure
inhibits tilting of the bailer as it slowly descends into the
liquid being sampled, i.e., it helps maintain the bailer in an
upright configuration as it descends into the liquid being sampled.
As in the third and fourth embodiments, stabilizer 46 may be used
with or without the plug and perforation of the first two
embodiments.
[0046] It will thus be seen that the objects set forth above, and
those made apparent from the foregoing description, are efficiently
attained. Since certain changes may be made in the above
construction without departing from the scope of the invention, it
is intended that all matters contained in the foregoing description
or shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
[0047] It is also to be understood that the following claims are
intended to cover all of the generic and specific features of the
invention herein described, and all statements of the scope of the
invention which, as a matter of language, might be said to fall
therebetween.
[0048] Now that the invention has been described,
* * * * *