Railways – Tubular way
Reexamination Certificate
2001-07-02
2002-08-06
Morano, S. Joseph (Department: 3617)
Railways
Tubular way
C104S138200, C105S365000
Reexamination Certificate
active
06427602
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to inspection apparatuses known in the industry as pipe crawlers. Pipe crawlers are used to inspect the interior of pipes and similar passageways associated with water and sewage systems, industrial piping such as chemical or gas conduits, and piping used within nuclear reactors or related caustic or high stress environments. Pipe crawlers are frequently used to deploy monitoring equipment including sensors and/or cameras, to monitor the pipe integrity, and to help diagnose needed repairs or maintenance.
BACKGROUND OF THE INVENTION
Pipe crawlers, pipe inspection “rabbits” and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks, and process vessels for damaged or flawed structural features. Typically, such devices include a testing probe, sensor, or camera carried by a support structure that travels through the piping system being inspected.
Many of the remote inspection devices have been designed for pipes having a six-inch or greater inner diameter. However, there remains a need for the inspection of smaller diameter pipes. While current advances in miniaturization technology have made cameras and sensors small enough to fit within a small diameter pipe, there have been few advances in the design of a delivery vehicle having adequate motive forces to deploy a small diameter inspection vehicle through a pipe system. For example, miniature electric motors do not provide enough motive force to pull extensive length tethers behind the crawler. Similarly, miniature air cylinders do not have the capacity to generate enough pushing force directly against the inner-walled pipe as is required for inch-worm motion.
The art teaches a variety of pipe inspection apparatuses. Two such apparatuses are taught in U.S. Pat. Nos. 5,770,800 and 5,398,560, assigned to the U.S. Department of Energy and incorporated herein by reference. These pipe inspection apparatuses move through the use of differential hydraulic pressure or the use of a pipe pig to carry the apparatus.
U.S. Pat. No. 4,460,920 to Weber describes a remote controlled pipe crawler having front and rear stepping bodies interconnected by a gimbal joint. U.S. Pat. No. 4,601,204 Fournot et al teaches a duct crawler having pneumatically or hydraulically operated pivot arms and rubber gripping feet used in a pull-pusher combination mode. However, there are limitations to the size and motive force capable of being exerted by the prior art devices as set forth above.
In particular, there is a need for a pipe inspection apparatus delivery vehicle that will provide the necessary motive force for small diameter pipes. The apparatus should be dimensioned to pass through various sizes of piping and be able to readily negotiate bends in the piping. In addition, the pipe crawler should be able to generate a sufficient motive force that can propel inspection equipment and the resulting physical and electronic tether through extended lengths of piping.
Accordingly, there remains room for variation and improvement within the art.
SUMMARY OF THE INVENTION
One aspect of the present invention is to provide a flexible pipe crawler having sufficient motive force to successfully traverse small diameter pipes while attached to remote monitoring equipment and sensors.
It is yet another aspect of the present invention to provide a pipe crawler apparatus in which a pneumatic piston is used to actuate a plurality of pivoting grip members, each grip member being used to engage the interior of a pipe.
It is an additional aspect of the present invention to provide a pipe crawler capable of negotiating 3 inch and 4 inch inner diameter pipe using the selective, intermittent pushing and pulling action of an air cylinder. The air cylinder is operatively connected on opposite ends to a respective first gripping unit and a second gripping unit. The first and the second gripping units are used to selectively engage and disengage the pipe crawler with respect to the interior of the pipe while the intervening air cylinder proceeds to move the non-engaged gripping unit within the pipe.
It is yet another aspect of the present invention to provide an improved gripping unit for use in a pipe crawler apparatus. The gripping unit translates the linear motion of a piston rod to bring about the pivoting action of multiple support posts. Each post carries on a non-pivoting end a gripping member adapted for engaging an inner pipe surface.
The gripping pneumatic unit provides a stronger interengagement with the pipe interior than the direct application of a piston rod against the interior surface of a pipe. Accordingly, the gripping unit of the present invention enables a pipe crawler apparatus that can operate carrying a greater weight load than a conventionally constructed pipe crawler.
Further, the present invention allows a compact design having sufficient motive force capability such that small diameter pipes may be accessed and surveyed using the pipe crawler constructed according to the present invention.
These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims.
REFERENCES:
patent: 3298399 (1967-01-01), Slade
patent: 3642032 (1972-02-01), Cook et al.
patent: 3665187 (1972-05-01), Stein
patent: 4006359 (1977-02-01), Sullins et al.
patent: 4252152 (1981-02-01), Martin et al.
patent: 4601204 (1986-07-01), Fournot et al.
patent: 4919223 (1990-04-01), Egger et al.
patent: 4991651 (1991-02-01), Campbell
patent: 5018451 (1991-05-01), Hapstack
patent: 5121694 (1992-06-01), Zollinger
patent: 5309844 (1994-05-01), Zollinger
patent: 5375530 (1994-12-01), Zollinger et al.
patent: 5944326 (1999-08-01), Ishibashi et al.
patent: 6031371 (2000-02-01), Smart
Blackmon Bruce L.
Erickson Scott A.
Hovis Gregory L.
Dority & Manning PA
Jules Frantz F.
Morano S. Joseph
Westinghouse Savannah River Company LLC
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