The present invention is related in general to cost effective, efficient systems and methods to size and shape pipe, particularly for applications with critical dimensional tolerances and/or irregular configurations.
Conventional continuous tube rolling mills are extremely complex installations requiring large capital investments that can only be paid back if high capacities are well utilized. There is a rising demand world-wide, however, for smaller capacity plants with a correspondingly lower investment burden. This is particularly true in the specialty pipe business, where manufacturing specialty pipe from long hollow tubes may be cost prohibitive.
Specialty pipe (or tubing) refers to a wide variety of high-quality, custom-made tubular products requiring critical tolerances, precise dimensional control and special metallurgical properties. Specialty pipe is typically used in the manufacture of automotive, construction and agricultural equipment, oil country tubular good (OCTG) applications, petrochemical applications, and industrial applications such as hydraulic cylinders, machine parts and printing rollers. OCTG is a label typically applied to the pipe products used by petroleum exploration and production customers, such as tubing, casing, pup joints, risers and couplings.
In order to produce specialty pipe that meets more stringent standards, pipe produced from traditional methods, such as electric resistant welding (ERW) technology, is then worked to form specialty pipe with more exacting qualities. Often, specialty pipe needs to be sized in order to meet customer standards. Typical methods to decrease an outer diameter of a pipe involve using rollers or drawing through a die. Using rollers typically is disadvantageous because roller systems often cannot produce pipe with tight tolerances. Many specialty pipes, such as stabilizer bars in the automotive industry, require precise tolerances of 9/1000's of an inch.
Other methods of sizing pipe, such as drawing through a die, may produce pipes with tight tolerances. However, drawing systems have disadvantages as well. Drawing a pipe through a die typically requires auxiliary pre-treatment and post-treatment operations. For example, required pre-treatment operations include pickling and lubricating the pipe as well as swaging one end of the pipe (thereby creating about a 12% material loss). Drawn pipes also typically require post-treatment operations to straighten and stress relieve the tube. Stress relieving is often necessary because typical drawing systems use mandrels that cause the pipe to lose a significant portion of the pipe's fracture toughness when drawn through an associated die.
In accordance with teachings of the present invention, a system and method are described for sizing pipe that substantially reduce disadvantages and problems associated with previous systems and methods of sizing pipe. In one embodiment, a pipe sizing system includes a die having an opening operable to size the pipe, a hydraulic cylinder having at least one rod attached thereto, the hydraulic cylinder and the at least one rod cooperating with each other to push the pipe through the die, and a receiver to guide the pipe as the pipe exits from the die.
In another aspect of the invention, a push bench system for sizing a pipe includes a die having an opening operable to size the pipe, a hydraulic cylinder having at least one rod attached thereto, the hydraulic cylinder and the at least one rod cooperating with each other to push the pipe through the die to form a sized pipe, a receiver to guide the sized pipe as the sized pipe exits from the die. The receiver is operable to manipulate the sized pipe to form a specific shape or configuration.
In one embodiment of the present invention, a push bench system for sizing at least two pipes includes at least two dies having openings operable to size the at least two pipes, a hydraulic cylinder having at least two rods attached thereto, the hydraulic cylinder and the at least two rods cooperating with each other to push the at least two pipes through the at least two dies, and at least two receivers to guide the at least two pipes as the at least two pipes exit from the at least two dies. In a particular embodiment, the at least two dies comprise three dies, the at least two rods comprise three rods, and the at least two receivers comprise three receivers.
In another embodiment of the present invention, a method of reducing an outside diameter of a pipe includes positioning the pipe to pass through a die having a longitudinal axis, pushing the pipe through the die using at least one hydraulic cylinder, and controlling movement of the pipe vertically (x direction) and laterally (y direction) relative to the longitudinal axis as the pipe exits from the die. In one embodiment, the method further includes simultaneously pushing a second pipe and a third pipe through a second die and a third die using the at least one hydraulic cylinder. In another embodiment, the method further includes pushing the pipe through a die without the use of a mandrel.
In one embodiment of the present invention, a method of reducing an outside diameter of a pipe includes positioning the pipe to pass through a die having a longitudinal axis, pushing the pipe through the die using at least one hydraulic cylinder, controlling movement of the pipe vertically (x direction) and laterally (y direction) relative to the longitudinal axis as the pipe exits from the die, and performing at least one post-die operation as the pipe exits from the die. In certain exemplary embodiments, the at least one post-die operation includes treating the pipe. In other exemplary embodiments, the at least one post-die operation includes inspecting the pipe.
In another embodiment of the present invention, a method for forming a push bench operable to size a pipe includes installing a die having a longitudinal axis and an opening operable to size the pipe, installing a hydraulic cylinder having at least one rod attached thereto along the longitudinal axis, and installing a receiver along the longitudinal axis.
Teachings of the present invention may be used to size portions of pipe used in automotive, construction and agricultural equipment as well as OCTG, petrochemical, and other industrial applications.
A more complete and thorough understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:
Preferred embodiments of the invention and its advantages are best understood by reference to
As shown in
Hydraulic cylinder 14 may be attached to rod 16. Rod 16 releasably engages pipe 18 and serves to move pipe 18 into die assembly 70. In order to push pipe 18 through die 12, rod 16 preferably includes coupling 19 with inside diameter 108 that is greater than outside diameter 104 of pipe 18. (See
Rod 16 may be associated to pipe 18 through the use of coupling 19. Coupling 19 may be a hollow cylinder that is operable to releasably attach rod 16 to pipe 18.
Pipe 18 may generally include, but not be limited to, welded steel pipe or ERW pipe. Welded pipe is often manufactured from coiled steel or plate steel through a pipe-making method such as an ERW (electric-resistance-welding) pipe-making method, a TIG (Tungsten Inert Gas) welding pipe-making method, or a laser welding pipe-making method, to thereby obtain pipe 18. In certain embodiments of the present invention, pipe 18 has outside diameter 104 of about one inch to about five and one-half inches prior to sizing. (See
For the purposes of this application, pipe 18 may refer to any of the following: a pipe, a tube, pipes, tubes or combinations thereof. Different industries may differentiate between the terms pipe and tube. For example, some industries may refer to a pipe as a finished product and a tube as an unfinished product. The difference between the terms pipe and tube may also encompass the difference in dimensional control. For example, a tube may have dimensional control over the inside diameter, outside diameter and wall thickness. Rather, a pipe may only have dimensional control over the inside diameter and wall thickness. For the above reasons, the term pipe 18 should be read to include pipe, tube, pipes, tubes, related structures and/or combinations thereof.
In optional embodiments of the present invention, push bench section 40 may include support 24. Support 24 may brace pipe 18 and prevent pipe 18 from buckling while being pushed through die 12. Support 24 may also help guide pipe 18 through die 12. Support 24 preferably supports about a midpoint of pipe 18. In some embodiments, support 24 may be a movable support. As shown in
Pipe sizing system 20 includes die assembly 70. Die assembly 70 may include die housing 11 and die 12. Die 12 reduces outside diameter 104 of pipe 18 to form outside diameter 106. (See
In one embodiment of the present invention, once pipe 18 exits die 12, pipe 18 enters receiver section 80. In certain embodiments, receiver section 80 may include receiver 22, receiving guide 27, rails 29a and 29b, receiver table 62, and rail stop 32. Receiver 22 couples to pipe 18 and guides pipe 18.
In certain embodiments of the present invention, pipe sizing system 20 may include a variety of post-die operations.
Once pipe 18 has been positioned, the method proceeds to step 124 where an operator must decide if pipe 18 needs support 24. Factors such as the length and diameter of pipe 18 may determine if the operator decides to use support 24. If the operator decides not to use support 24, then the method continues to step 128. If the operator decides to use support 24, then the method proceeds to step 126 where support 24 is added to brace pipe 18. In certain exemplary embodiments, support 24 braces pipe 18 at about the midpoint of pipe 18. After pipe 18 has been braced by support 24, the method proceeds to step 128.
At step 128, at least one hydraulic cylinder 14 pushes pipe 18 through die 12. During this process outside diameter 104 of pipe 18 is reduced to outside diameter 106. (See
Embodiments of the present invention include pushing pipe 18 through die 12 without the use of a mandrel. By not using a mandrel, pipe 18 may lose less fracture toughness than if a mandrel was used.
Once a portion of pipe 18 exits die 12, the method moves to step 130, where the movement of pipe 18 is controlled vertically and horizontally relative to longitudinal axis 43.
At step 130, an operator may decide to produce a straight pipe by using receiver 22 in pipe sizing system (See
Once pipe 18 has passed through die 12, the method proceeds to step 132. At step 132, an operator may optionally decide whether to perform a post-die operation on pipe 18. One post-die operation an operator may decide to perform is to treat pipe 18. If the operator decides not to treat pipe 18, the method proceeds to step 136. If the operator decides to treat pipe 18, the method proceeds to step 134, where pipe 18 may be treated by at least one pipe treatment device. Pipe treatment devices may include austenizing coil 80, water quenching coil 82, tempering coil 84, coating and/or phosphating machine 86, dryer 88, drill 90 and combinations thereof. Once pipe 18 has been treated, the method proceeds to step 136.
At step 136 an operator may optionally decide to inspect pipe 18. If the operator decides not to inspect pipe 18, the method proceeds to step 140 where pipe 18 is ready for use. If the operator decides to inspect pipe 18, the method proceeds to step 138 where inspection device 94 inspects pipe 18. In certain embodiments, inspection device 94 may be an ultrasonic inspection device. Once pipe 18 has been inspected the method proceeds to step 140 where pipe 18 is ready for use.
The previous methods and systems may be used to produce pipe for use in portions of automotive, construction and agricultural equipment and in industrial applications such as hydraulic cylinders, machine parts and printing rollers. Such examples of automotive industry pipe include, but are not limited to, stabilizer tubes.
The previous methods and systems may also be used to produce line pipe, casing and tubing as well as other applications. Line pipe is typically used in the surface transmission of oil, natural gas and other fluids. Casing or well casing, is typically used as a structural retainer for oil and gas wells. Casing is used to prevent contamination of both the surrounding water table and the well itself. Casing preferably lasts the life of a well and is not usually removed when a well is plugged and abandoned. Tubing may refer to OCTG applications and petrochemical applications. When referring to OCTG, tubing is a separate pipe used within the casing to conduct the oil or gas to the surface. Depending on conditions and well life, tubing may have to be replaced during the operational life of a well. When referring to petrochemical applications, tubing may refer to tubes used to transport chemical substances within a petrochemical plant. All the above applications list potential uses for pipe 18 sized according to methods and systems of the present invention. This list does not limit the other potential applications of pipe 18 formed in accordance with teachings of the present invention.
Embodiments of the present invention also include methods for forming a push bench operable to size pipe 18. The methods include installing die 12 having longitudinal axis 43 and opening 41 able to size pipe 18; installing hydraulic cylinder 14 having at least one rod 16 attached thereto along longitudinal axis 43; and installing a receiver (22 or 50) along the longitudinal axis 43.
Optionally the method may include installing at least one support 24 along longitudinal axis 43 to brace pipe 18 before entering die 12 and/or installing at least one coupling 19 to releasably secure pipe 18 to rod 16. Optionally, the method of forming a push bench may include installing at least one pipe treatment device and/or at least one pipe inspection device.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the following claims.
This patent application is a continuation of U.S. patent application entitled Push Bench and Method of Manufacturing Small Diameter Tubing, Ser. No. 11/038,807, filed Jan. 19, 2005, now U.S. Pat. No. ______, which claims the benefit, under 35 U.S.C. §119(e), of previously filed provisional patent application entitled Push Bench and Method of Manufacturing Small Diameter Tubing, Ser. No. 60/610,308, filed Sep. 16, 2004. The contents of these applications are incorporated herein in their entirety by this reference.
Number | Date | Country | |
---|---|---|---|
60610308 | Sep 2004 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11871653 | Oct 2007 | US |
Child | 12623168 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11038807 | Jan 2005 | US |
Child | 11871653 | US |