Lockable well cap

A lockable well cap for capping the upper end of a well casing. A base member, which has an upwardly and inwardly interior surface with tapered upwardly directed serrations formed thereon, frictionally engages a portion of the well casing. The outside surface of the base member has a lock tab which aligns with a lock tab on the cover to receive a locking padlock. The cover also includes pins which contact inclined grooves in the base member when properly engaged. A first fluid impervious gasket is seated between the well casing and the base member, and a second fluid impervious gasket is seated between the base member and the cover, both to provide a watertight and waterproof seal.

TECHNICAL FIELD 
This invention relates to caps for pipes, and more particularly to lockable 
well caps. 
BACKGROUND ART 
Numerous devices are known for capping the end of a pipe. None of these 
devices, however, are suitable for use as a protective cover for monitor, 
sniffer and/or recovery wells. These wells, when properly installed, 
require a waterproof and watertight cap to aid in sealing off any surface 
run-off and potential contamination. A watertight and weatherproof cap is 
essential in maintaining the integrity of an aquafer of interest during 
the monitoring process. No known cap provides a lockable, watertight, and 
weatherproof seal. 
Also, in the monitoring well industry, the well casing is often cut with a 
hand saw. This procedure results in an uneven and often jagged finish on 
the top of the well casing. No known well cap will provide a watertight 
and weatherproof seal at the top of the well casing when the finish is 
uneven and jagged. 
Those concerned with these and other problems recognize the need for an 
improved lockable well cap. 
DISCLOSURE OF THE INVENTION 
The present invention provides a lockable well cap for capping the upper 
end of a well casing. A base member, which has an upwardly and inwardly 
interior surface with tapered upwardly directed serrations formed thereon, 
frictionally engages a portion of the well casing. The outside surface of 
the base member has a lock tab which aligns with a lock tab on the cover 
to receive a locking padlock. The cover also includes pins which contact 
inclined grooves in the base member when properly engaged. A first fluid 
impervious gasket is seated between the well casing and the base member, 
and a second fluid impervious gasket is seated between the base member and 
the cover, both to provide a watertight and waterproof seal. 
An object of the present invention is the provision of an improved lockable 
well cap that is easy to install. 
Another object of the present invention is to provide a lockable well cap 
that will provide a watertight and waterproof seal to avoid contaminants 
from entering the well. 
A further object of the invention is the provision of a lockable well cap 
that will provide a watertight and waterproof seal on the jagged cut top 
edge of a well casing. 
Still another object of the present invention is to provide a lockable well 
cap that allows for easy access to the locking padlock. 
A still further object of the present invention is the provision of a 
lockable well cap that is inexpensive to manufacture.

BEST MODE FOR CARRYING OUT THE INVENTION 
Referring now to the drawings, wherein like reference numerals designate 
identical or corresponding parts throughout the several views, FIG. 1 
shows the lockable well cap (10) of the present invention. The lockable 
well cap (10) is designed to cap the upper end of a well casing (20). The 
well casing (20) may be formed of various materials including unthreaded 
PVC plastic pipe having an uneven jagged upper edge (22). 
As best shown in FIGS. 2 and 4, the well cap (10) includes a base member 
(30), a cover (50), and O-rings (60 and 70). The base member (30) includes 
a body section (32) that is formed of an open cylinder. The body section 
(32) has an interior surface that is upwardly and inwardly tapered to 
frictionally receive the upper end of a well casing (20). A number of 
axially spaced rings (34) are milled into the interior surface and include 
upwardly directed pointed edges (36) that form serrations to secure the 
base member (30) in position. An annular seat (38) is also milled into the 
interior surface to receive an O-ring (70). 
The exterior surface of the body section (32) includes an annular shoulder 
(40) and a radially extending first lock tab (42) having an oblong opening 
(43). A lip (46) extends up from the shoulder (40) and carries a pair of 
inclined grooves (48). 
The cover (50) includes a knurled rim (52) and a downwardly extending 
flange (54) that carries a pair of radially extending pins (56) on its 
interior surface. A second lock tab (58) extends radially outward from the 
flange (54) and has an oblong opening (59). An O-ring (60) is used to 
provide a sealed connection between the base member (30) and the cover 
(50). The O-rings (60 and 70) are fluid impervious gaskets having a 
circular cross section. It is to be understood that the O-rings (60 and 
70) may be formed of various suitable materials including rubber, 
neoprene, nylon and Teflon. 
In use, the first O-ring (70) is positioned in the annular seat (38) in the 
interior surface of the body section (32). The base member (30) is then 
positioned over the upper end of the well casing (20) and a hammer or 
mallet is used to force the tapered interior surface of the base member 
(30) down on the well casing (20). The interior surface is sized such that 
the upper edge (22) of the unthreaded well casing (20) will be disposed 
above the O-ring (70) when the base member (30) is in the full down 
position. The O-ring (70) thus provides a seal between the exterior 
sidewall of the well casing (20) and the interior surface of the body 
section (32). The upwardly directed pointed edges (36) of the rings (34) 
prevent removal of the base member (30) once it is securely attached to 
the well casing (20). 
With the base member (30) secured in position, the second O-ring (60) is 
positioned to rest on the horizontal shoulder (40) adjcent the vertical 
lip (46). The cover (50) is then positioned so that the pins (56) align 
with the top of the inclined slots (48). By turning the cover (50) about 
90 degrees, or one-quarter turn, the cover (50) compresses the second 
O-ring (60) to provide a seal between the base member (30) and the cover 
(50), and simultaneously aligns the openings (43 and 59) in the first and 
second lock tabs (42 and 58). The link (80) of a padlock (82) is then 
inserted through the openings (43 and 59) and the padlock (82) is closed. 
Since the oblong openings (43 and 59) are larger than the link (80) of the 
padlock (82), the padlock (82) may be rotated and inverted to provide 
convenient access to the keyway when the access to the area surrounding 
the lockable well cap (10) is limited. 
Thus, it can be seen that at least all of the stated objectives have been 
achieved. 
Obviously, many modifications and variations of the present invention are 
possible in light of the above teachings. It is therefore to be understood 
that, within the scope of the appended claims, the invention may be 
practised otherwise than as specifically described.