JPS6282312A - Method and instrument for inspecting outer peripheral seal fitting of oil well tube - Google Patents

Abstract

PURPOSE:To perform inspection without using any seal fitting gauge by moving forth plural measuring instruments arranged on the outer peripheral side of a tube to be inspected synchronously from outside the tip of the tube to be inputted toward the tube to be inspected. CONSTITUTION:The tube 1 to be inspected is fixed at a specific position on the forward prolongation of a main base axis G. Then a moving table 16 is moved forward to a measurement position and then the main base 10 is connected and fixed to the tube 1. Then when the tube end detector 6 of a measuring instrument 5 detects the tube end of the tube 1 as a measuring base 13 moves forward, a measuring base movement extent measuring device 14 measures the quantity of forward movement of the measuring instrument 5 on the basis of the tube end detection point as an origin and a tube-diameter measuring instrument 7 measure the tube diameter simultaneously. This tube-diameter measurement is carried out at least two positions in the taper area of the outer peripheral seal surface and at least one position in the parallel area of the outer peripheral seal surface. Thus, the tube diameter is measured by each measuring instrument and the mean tube diameter at each position and the taper in the taper area are calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inspection method and apparatus for inspecting the fitting of an outer peripheral seal surface formed on the tip lip of an oil country tubular goods constituting a pipe joint for oil country tubular goods. .

[Prior Art] Conventionally, a method for inspecting the fit of the outer seal surface formed at the tip lip of an oil country tubular goods is to use a seal fitting gauge on the outer seal surface 1a of the pipe to be inspected 1, as shown in FIG. 2 was externally fitted with a predetermined fitting force, and the dimension E from the end surface 2a of the seal fitting gauge 2 to the tube end 1b of the tube to be inspected 1 was determined as a standoff value for inspection. Although this fitting inspection is mainly performed manually, there is a need to develop a similar inspection technique in order to improve inspection efficiency. As a mechanical inspection technique, it may be considered to apply and develop the oil country tubular screw fitting inspection technique described in Japanese Patent Publication No. 58-21203 or Japanese Patent Application Laid-Open No. 59-7242. That is,
As shown in Fig. 7, this screw fitting inspection technique involves mechanically bringing the screw fitting gauge 3 into contact with the threaded portion 1C of the pipe to be inspected 1 in an aligned state, and then tightening it to a specified level using torque. The dimension from the screw fitting gauge 3 to the tube end 1b is determined as the standoff value. It is possible to meet the above request by replacing the screw fitting gauge 3 in this screw fitting inspection technique with the seal fitting gauge 2.

[Problems to be Solved by the Invention] However, in the fitting inspection technique using the seal fitting gauge 2, it is difficult to completely align the axis of the pipe to be inspected 1 with the axis of the seal fitting gauge 2 immediately before starting fitting. It is extremely difficult to inspect the outer circumferential sealing surface 1a in an intact state while maintaining a non-contact state between the two, due to technical limitations not only in manual methods but also in mechanical methods. Therefore, in the fitting inspection technique using the seal fitting gauge 2, inspection scratches may occur on the outer peripheral seal surface 1a, which requires surface finish accuracy, and in the worst case, the tube 1 to be inspected may be damaged. This has the drawback of causing defective products and lowering yield.

SUMMARY OF THE INVENTION In order to solve the above-mentioned drawbacks, the present invention provides a fitting inspection method and an inspection apparatus for the outer peripheral seal surface of an oil country tubular goods pipe, which can be inspected without using a seal fitting gauge.

[Means for Solving Problems] The first invention, a fitting inspection method for the outer peripheral sealing surface of oil country tubular goods, is as shown in FIGS. 1 to 5.
A plurality of sets of measuring tools 5 equipped with a tube end detector 6 and a pipe diameter measuring device 7 are arranged at an appropriate circumferential pitch P on the outer circumferential side of the The measuring tools 5 are moved forward from the outside of the tip of the pipe 1 toward the pipe 1 to be inspected in a synchronous state, and the amount of forward movement of each measuring tool 5 is counted starting from the time when the tube end detector 6 in each measuring tool 5 detects the detection. The pipe diameter is measured with the pipe diameter measuring device 7, and based on the measured values of these pipe diameter measuring devices 7, 7... arbitrary points A and B of the outer peripheral sealing surface 1a formed on the tip lip of the pipe to be inspected 1 are measured. , C (see Figure 5).

Further, as shown in these figures, the inspection device which is the second invention includes a main base plate 10 which is freely swingably suspended from the other end of a balance rod 9 having a balance weight 8 at one end, and the main base plate 1.
The main base axis G that is provided near the center of 0 and runs along the front and back direction.
a centripetal device 12 equipped with a plurality of sets of tube inner circumferential surface pressers 11 that expand and contract in the radial direction relative to each other at an appropriate circumferential pitch Q;
10, a measurement base 13 that is movable back and forth; a measurement base moving port measuring device 14 that measures the longitudinal movement dimension of the measurement base 13; 13, and a plurality of sets of measuring tools 5 each having a tube end position detector 6 and a tube diameter measuring device 7.

[Function 1] The first invention, the fitting inspection method for the outer peripheral sealing surface of an oil country tubular goods country pipe, uses a plurality of sets of measuring tools 5.5 and 5.
... are advanced synchronously from the outside tip B of the tube 1 to be inspected toward the tube 1 to be inspected, so just by passing the measuring tool 5.5... - times, the outer seal surface of the tube to be measured is The pipe diameter and taper at arbitrary locations A, B, and C (see Figure 5) can be measured.

In addition, the second invention, the inspection device, includes a fixed pipe to be inspected 1
Since the movable main board 10 can be connected and fixed by the centripetal device f112, the measuring instruments 5.5... can be instantly made ready for measurement, and the detection time of the tube end detector 6 in each measuring instrument 5 can be detected. Measurement base moving layer measuring device 1 counted as a starting point
4 and the pipe diameter measured by the pipe diameter measuring device 7, the outer peripheral seal surface 1a formed at the tip lip of the pipe to be inspected 1
Any part A, B of.

An average outer diameter and taper of C (see FIG. 5) can be obtained.

[Explanation of Examples] Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

FIG. 1 is a longitudinal sectional side view showing an embodiment of an inspection device according to the second invention, and FIG. 2 is a front view thereof. In the following description, "front" means the right side in FIGS. 1, 3, and 4, and "rear" means the left side in these figures.

As shown in FIGS. 1 and 2, a movable table 16 is arranged on guide rails 15a, 15a of the base frame 15 so as to be movable back and forth. The moving table 16 is driven by a feed screw 17 provided on the base frame 15, and is moved to a standby position (see Fig. 1).
and stops at the measurement ready position M (see Figure 4). Mobile platform 1
A balance rod 9 is pivotally supported 19 on top of the balance rod 9, and the balance rod 9 is equipped with a balance weight 8 at its rear end, and a main base plate 10 is suspended from its front end via a ball joint 20 so as to be able to freely swing in almost all directions. It's lowered. Near the center of the main base 10,
A centripetal device 12 is provided for connecting and fixing the main board 10 to the tube 1 to be inspected. The centripetal device 12 includes four sets of pipe inner circumferential surface pressing tools 11 connected to the tip of an operating shaft 11b that moves back and forth on the front and rear ends of the bifold link 11a, and the main base 10 via a bottle, arranged at an appropriate circumferential pitch Q. Each pipe inner circumferential surface pressing tool 1 is pressed in the radial direction with respect to the main base axis G along the direction.
The first pressing surface is designed to expand and contract in a synchronous manner. Further, a measurement base 13 is disposed on the front side of the main base 10 so as to be movable back and forth. The measurement base 13 is driven by a feed screw 21 provided on the main base 10 and advances from a standby position (see FIG. 4) to a measurable position (not shown), and the amount of movement is determined by The measurement base movement amount measuring device 14 sequentially counts. Further, the measurement base 13 includes a measurement tool group 4 consisting of a plurality of sets of measurement tools 5 arranged on the outer periphery of the main base axis G at appropriate circumferential pitches P with this axis G as the center. Each measuring tool 5 is equipped with a tube end detector 6 and a tube diameter measuring device 7, as shown in FIG. 3, which is a detailed view thereof. The tube end detector 6 connects the detection end 6d of the bending link 6C, which is pivoted 6b in the casing 5a, with a compression spring 6.
e is biased forward, and a sensor 6f consisting of a differential transformer or the like is configured to emit a tube end detection signal. The pipe diameter measuring device 7 is constructed by attaching a sensor 7b such as a differential transformer or a magnetic scale to the tip of a piston rod 1a that moves from a standby position to a measurable position. Note that the pipe diameter measuring instrument 7 is not limited to the above-mentioned contact type, and may be a non-contact type that measures the pipe diameter by trigonometry using a laser spot light, although not shown.

Next, a procedure for inspecting the fit of the outer seal 1a of the tube to be inspected 1 using the inspection device will be described.

First, as shown in FIG.
is placed on standby, and the tube to be inspected 1 is fixed at a predetermined position on the forward extension of the main base axis G using a chuck device 22 (see FIG. 4). Next, after advancing the moving table 16 to the measurement position, the fourth
As shown in the figure, the operation shaft +1b of the centripetal device 12 is activated, and the main base plate 10, which is suspended so as to be freely swingable, is pressed against the pressure surface of each tube inner circumferential surface pressing tool 11 whose diameter has been expanded, and the pipe to be inspected is
Connect and fix. As a result, the tube axis F to be inspected and the main base axis G are naturally placed on a straight line. Subsequently, the measurement base 13 is advanced. As the measurement base 13 moves forward, the tube end detector 6 of the measurement tool 5 moves toward the tube to be inspected 1, as shown in FIG.
When the tube end is detected (the state shown in the lower part of the figure), the measurement base movement measuring device 14 (see FIG. 1) measures the measuring tool 5 starting from the detection by the tube end detector 6. The pipe diameter is measured with the pipe diameter measuring device 7 while counting the amount of forward movement. In this case, the detection end 6d of the tube end detector 6 when detecting the tube end
Since the dimension H from to the detection end IC of the tube end detector 6 is known from a pre-tested test, the tube diameter can be measured in relation to the longitudinal distance starting from the tube end of the tube to be inspected 1. can. This pipe diameter measurement is performed at a predetermined longitudinal distance from the pipe end at at least two locations (A and B in the figure in the case of the embodiment) in the tapered region of the outer seal surface 1a, and Measurement is performed at at least one location (C in the figure in the case of the example) in the parallel region of . After measuring the pipe diameter at each location with respect to each measurement tool 5, the average pipe diameter at each location and the taper king in the tapered region are calculated. If the axis F of the tube to be inspected is inclined at an intersection angle θ with respect to the main base axis G, each measuring instrument 5 detects the tube end at a different time, so the measuring instruments 5.5 and 5. The crossing angle θ can be determined based on the distance that the measurement base 13 has moved between the time when the pipe end is first detected and the time when the pipe end is last detected due to the synchronous advance of the pipes. Then, the pipe diameter measured in the inclined state is corrected based on the intersection angle θ obtained in advance, and each of the points A, B,
Obtain the average pipe diameter at C. In addition, measuring tool 5.5...
The process of determining the average outer diameter from the data obtained from the data can be performed not only by hand calculation but also by using an electronic computer or the like. By the way, the reason why the pipe diameter is evaluated using an average value is that even if the outer seal surface 1a of the pipe to be inspected 1 is not a perfect circle, it will elastically deform and become a perfect circle during actual use when connected to a coupling etc. This is because it can be made to correspond to a state that is close to the current state. Finally, when the measuring tools 5, 5... have advanced to the measurement end position and finished measuring the pipe diameter, the measurement base 13 is moved backward, the centripetal device 12 is set to the unconnected and fixed state, and the movable base 16 Retract to the standby position and complete the measurement.

The standoff S can be calculated from the obtained average outer diameter and taper T using the following formula.

S= (D-DIS)X (T-TIN)
l) a+ is the design value of the pipe diameter at the measurement location, and TI
is the design value taper at the measurement point, T-Tm
, DD+a, the standoff si obtained as a measurement result has zero deviation from the standard standoff value.

[Effects of the Invention] As detailed above, the present invention has the following excellent effects.

■ Since it is possible to inspect the fit of the outer seal surface of oil country tubular goods without using a seal fit gauge, there will be no inspection scratches on the outer seal surface, which requires surface finish accuracy, and the yield will be improved. Improvements can be made.

■ In normal measurement operations, the axes of the measuring tools and the axis of the tube to be inspected naturally match, but even if they do not match completely, the pipe diameter and taper can still be measured. Moreover, since the measurement can be completed by just passing the measuring instruments group once, the inspection can be carried out in a short time, and the inspection efficiency can be improved.

■ Since there is no need to store and manage seal fitting gauges, inspection work efficiency can be improved.

[Brief explanation of drawings]

1 to 5 show embodiments of the present invention,
FIG. 1 is a longitudinal side view showing an embodiment of the inspection device according to the second invention, FIG. 2 is a front view of the same, FIG. 3 is a longitudinal side view of the measuring tool, and FIG. A longitudinal side view showing a state in which it is connected and fixed to a pipe to be inspected, Fig. 5 is an enlarged side sectional view of the outer seal surface of the pipe to be inspected, and Fig. 6 is a main part of a conventional fitting inspection method for the outer seal surface of an oil country pipe. FIG. 7 is a cross-sectional side view of the main part of a conventional screw fitting inspection device. 1... Pipe to be inspected 4... Measuring tool group 5...
Measuring tool 6... Pipe end detector 7... Pipe diameter measuring device 8... Balance weight 9... Balance rod 1o... Main base 11... Pipe inner peripheral surface pressing tool 12... Centripetal device 13...Measuring base 14...Measuring base moving base Measuring head Figure 4 Figure 1 Figure 5 Figure 6 Figure 7

Claims (1)

[Scope of Claims] 1. A plurality of sets of measuring tools equipped with a pipe end detector and a pipe diameter measuring device are arranged at appropriate circumferential pitches on the outer circumferential side of a fixed pipe to be inspected, and the plurality of sets of measuring tools are are advanced in a synchronous manner from the outside of the tip of the tube to be inspected toward the tube to be inspected, and the amount of forward movement of each measuring instrument is counted starting from the time when the tube end detector of each measuring instrument detects the corresponding tube. The method is characterized in that the pipe diameter is measured with a diameter measuring device, and the average outer diameter and taper at any point on the outer seal surface formed at the tip lip of the pipe to be inspected are measured based on the measured values of the pipe diameter measuring device. A method for inspecting the fit of outer seal surfaces of oil country tubular goods. 2. A balance rod with a balance weight at one end, and a main base suspended from the other end so as to be freely swingable, and a scale installed near the center of the main base that expands and contracts in the radial direction with respect to the axis of the main base that runs in the front-rear direction. a centripetal device comprising a plurality of sets of pipe inner circumferential surface pressing tools arranged at an appropriate circumferential pitch, a measurement base provided on the main base that is movable back and forth, and a measurement base movement amount measurement device for measuring the back and forth movement dimension of the measurement base. An oil country tubular outer circumferential seal surface fitting comprising a device and a plurality of sets of measuring tools arranged on the measurement base at appropriate circumferential pitches on the outer periphery of the main base axis and equipped with a pipe end position detector and a pipe diameter measuring device. Inspection equipment.