US2336524A - Combination straightener and tester for pipes - Google Patents

Description

Dec. 14, 1943. B, BANNISTER 2,335,524

COMBINATION STRAIGHTENER AND TESTER FOR PIPES Filed Nov. 1, 1940 I z? ,2 L 'fi 7 y m /z 14 1: 1 Fl E. 4. 20 J? [mm d022- Patented Dec. 14, 1943 aaeaszi COMBINATION STRAIGHTENER AND- TESTER FOR PIPES Bryant Bannister, Mount Lebanon, 1%., assignor to National Tube Company,

New Jersey a corporation of Application November 1, 1940, Serial No. 363,932

2.- Claims. This invention relates to the manufacture of pipes and tubes and more particularly to the axial straightening and hydraulic pressure test-- ing thereof.

In the conventional manufacture of pipes and tubes they ar straightened as they leave the cooling table, subsequent to which the ends are cropped and beveled or threaded as desired. The usual equipment for performing the straightening. operation comprises ,a series of rolls set in opposed planes, or cross rolls with special profiles. Following the straightening operation, the pipe or tube is transferred to a test pump where it is filled with water and subjected to high pressure in order to determine whether or not there is leakage. The foregoing operations require a crew of workmen at the' straightening machine and another crew at the test pump. Usually. two test pumps spaced at substantial distances are re-' quired to handle the product of one pipe mill.

From the foregoing, it will be seen that considerable conveying and handling equipment is required to. straighten and test the pipe.

when a pipe or tube is su jected to tension,

there is an initial tendency for it to align itself with the direction of pull, provided, of course, the

tension is capable of stretching the material beyond its elastic limit. It is, accordingly, among the objects of the present invention to take advantage of this tendency while at the same time, or at least while in the same apparatus, subjecting the interior of the workpiece to the application of a suitable test fluid. It will, of course, be understood that when pipes and tubes may be straightened and tested in the same machine there will result a reduction in cost of labor and handling over that required of conventional practice.

Another object is to accomplish the foregoing ends by the provision of simple and relativ ly inexpensive instrumentalities.

The foregoing and other apparent after referring to the drawing, in which:

Figure 1 is a fragmentary plan of an apparatus embodying the teachings of the present invention; v

Figure 2 is an enlarged fragmentary plan of the left-hand portion of Figure 1 referred to hereinbefore;

Figure 3 is a side elevation of the showingof Figure 2, certainof the parts thereof being shown in section;

Figure 4 is an enlarged fragmentary elevation of the means for sealing the ends of thepipe to be straightened and tested:

objects will be more Figure 5 is a view on the line V-V of Figure 4;

I and,

Figure -6-is a sectional view on the line VI--VI of Figure 3.

Referring more particularly to the drawing, the numeral 2 generally designates a bed or base upon which there is received pipes or tubes to be tested, the latter, referred to hereinafter at X, being conveyed over a suitable skidway or other conveying device 3 preferably disposed at the discharge end of a cooling table (not shown).

Disposed at either end of the bed'or base 2 is a hydraulic cylinder 4 each containing a suitable piston (not shown) and having the piston rod 5 thereof extending inwardly and, therefore, in opposed relationship one with respect to the other. Carried on the inner and therefore the most adjacent ends of each-of the piston rods 5 is a clevis 6 to which there is pivotally connected as at! the converging inner ends of apair of toggle links 9, the latter carrying on their outer ends pivot pins l0 which are connected to the rearward ends of a pair of pliers, the latter being pivotally interconnected intermediate their ends as shown at 12. The gripping, ends of the pliers ll, designated at l3, are transversely concaved and provided with serrated edges l4. Disposed between the gripping ends l3 of each of the pairs of pliers II is a cylindrical plug l8 which carries on its outer end an exterior-1y screw threaded cylindrical portion 20 of reduced diameter. Connected to this cylindrical portion 20 is a coniform nozzle portion 22 having at the base thereof an interiorly threaded cylindrical recess 24. Referring more particularly to Figure 4 of the drawings, it will be perceived that while the rearward portion of the base of the nozzle 22 abuts the correspondingly adjacent surface of the plug I8,

there is provided between the said nozzle and the said plug an annular recess '26 which accommodates an annular, expansible tube 28 of suitable high strength resilient material. The plug I8 and nozzle 22 .are centrally bored as shown at 30 and the expansible annular tube 28 communicates therewith at diametrically opposite points, by way of being provided with tubes 32 which extend at least partially through radial passageways 34 which are conjointly formed from the forward andrearward portions of the plug I8 and nozzle 22, respectively. As shown most clearly in Figure 3, the central bore 30 through the plug l8 and nozzle 22 communicates adjacent the rear of the said plug with a right angularly extending aperture 35 which communicates with a suitable source of fluid under pressure (not shown). Ac-

- II and the conii'orm nozzle the overbalancing line when it is turned on.

cordingto the foregoing construction and arrangement, it will be seen that when fluid under pressure is applied to either one or'both of the right angular apertures 35 in the plugs d8, it will move through the central bore 30 in the plug 22, and completely flll the interior of the pipe or tube X to be tested. When the test fluid completely fills the pipe x some 01' the fluid will flow through the radial passageways 3!, tubes 32, and annular expansibie tubes 28, and cause the latter to expand outwardly. Accordingly, the ends of the test piece are disposed over th nozzles 22 and plugs l8 and within the gripp ends l3 of the pliers ll. As clearly shown in Figure 3, the plug ll serves as an internal support for the test piece, thus preventing the jaws l3 from causing it to collapse. As soon as fluid tight connections are maintained at either end or the test piece x and the interior of the latter supplied with test fluidunder the required pressure, fluid is admitted tovthe ad- Jacent ends of the cylinders 4, the pistons of which (not shown) are madeto draw the piston rods I in opposite directions. The drawing apart of the piston rods is continued sufliciently to stretch the test piece x beyond its elastic limit,' whereby it is straightened.

For supplying fluid under pressure through the apertures 35 at the rearward ends 01' the plugs I, a one-way valve 31 is provided in the low pressure line; and this is automatically closed by pressure of the higher pressure In order to accommodate test pieces X which vary as to length, one or both of the cylinders l is made adiustable in any-suitable manner (not shown) on the base or bed 2.

While I have shown and described a specific '1. Apparatus for straightening and pressuretesting a metallic tubular article, comprising.

combinedgripping and sealing means for each of the ends of the metallic tubular article, at least one or said means including a movable drawhead, gripping means carried by said movable drawhead for engaging the exterior of one end of said article, a sealing plug carried by said gripping means and adapted to sealfihe adjacent end 01 said article, said plug serving as an internal support for said article while it is being gripped, means operating through said sealing plug to admit test fluid to the interior of said article, and "means for moving said drawhead relative to the other combined gripping and sealing means suiliciently to stretch said article beyond its elastic limit.

2. Apparatus for straightening and pressuretesting a metallic tubular article, comprising combined gripping and sealing means for each 01' the ends of said article, each of said means including means for-gripping the exterior of one end of said article, a plug adapted to seal the adjacent 0 end of said article and toserve as an internal support for said article while it is being gripped, means operating through one of said plugs to admit test fluid to the interior of said article and means for moving said combined means relative to each other sufliciently to stretch said article beyond its elastic limit.

BRYANT nanms'ma.

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