JPH062137Y2 - Water immersion type ultrasonic flaw detection jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is used for inspecting a workpiece having a welded portion on a shaft portion, for example, an internal defect of the welded portion in an engine valve by a water immersion ultrasonic flaw detection method. For jigs used in.

[Conventional technology]

The shaft end of the valve stem portion of the engine valve is subjected to a strong force by the cam and rocker arm during intake and exhaust, so it must be subjected to heat treatment such as induction hardening to increase the hardness and have excellent wear resistance.

As one means for increasing the hardness, it is possible to weld a martensite type chip, which has high hardness in a quenched state and is excellent in wear resistance, to the shaft end.

The engine valve thus obtained is usually inspected by an ultrasonic flaw detector for the presence of internal defects in the weld.

Generally, for this inspection, a jig including a probe holder that holds a probe in an ultrasonic flaw detector and a work holder that holds a work, that is, a shaft portion of an engine valve is used. In this case, if the center of the probe is deviated from the center of the work shaft portion, or if the distance between the probe and the work shaft end is improper, the flaw detection accuracy is adversely affected.

Therefore, in the above jig, in order to facilitate centering and adjustment of dimensions, the probe holder and the work holder are
The probe is mounted on an appropriate base so that it can be moved horizontally, and the center of the probe and the axis of the shaft of the workpiece are in a horizontal state.

[Problems to be solved by the device]

Engine valves require particularly strict quality, so
For the ultrasonic flaw detection, a water-immersion flaw detection method with high flaw detection accuracy is often adopted.

In the water-immersion type flaw detection method, the probe and the work shaft part to be inspected are submerged in the work. Therefore, if the above-mentioned conventional jig is used, most of the jig and the work will be submerged in water. It will be.

Therefore, each time the work is replaced or the jig is adjusted, the hand must be put in the water, and the holding shaft hole (insertion hole) of the work shaft part of the work holder should also be immersed in the water. It becomes invisible and the workability at the time of work replacement is significantly reduced, and the inspection becomes inefficient.

The present invention has been made in order to solve the above problems, and provides a water immersion type ultrasonic flaw detection jig which has good workability when exchanging a work and can improve work efficiency. Has an aim.

[Means for Solving the Problems]

In order to achieve the above object, the jig of the present invention is a jig for water immersion type ultrasonic flaw detection which is performed by immersing an inspected portion of a work in water as a probe. A probe holder having a shaft hole for holding and a work holder having a shaft hole for holding the shaft part of the work are formed such that the axis lines of the shaft holes are obliquely aligned vertically and are aligned with each other. It is characterized in that at least the upper end of the shaft hole of the work holder is exposed from the water surface and at least one of them can be moved so as to be provided on an appropriate base.

[Action]

According to the present invention, the work holder is tilted so that the axis of the shaft hole is directed obliquely upward and downward, and the upper end of the shaft hole is exposed from the water surface. , It can be easily inserted from the obliquely upper side, and it is not necessary to put the hand in the water each time the work is replaced, and workability is greatly improved.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a jig (1) used for water immersion ultrasonic flaw detection in a partially cutaway manner. When inspecting, the non-inspection side of the workpiece and a part of the jig (1) are shown. The work is performed by exposing the water tank (2) from the water surface (2a) and immersing almost all other parts in the water.

The base (3) of the jig (1) is attached to the bottom of the base (3).
It is supported almost horizontally by bolts (4).

A probe holder (6) holding a probe (5) connected to an ultrasonic flaw detector (not shown) is provided on the upper surface of the front part of the base (3), and also in the center part, at the front part. A support block (7) having a downward sloping surface (7a) of approximately 45 ° is provided so as to be slidable in the front-rear direction.

As for the attachment part (6a) of the probe (5) in the probe holder (6), the central axis of the probe (5) is an inclined surface in the support block (7).
It is slightly tilted forward so that it is parallel to (7a).

As shown in FIG. 3, the support block (7) has a prismatic ridge (7b) formed in the center of its bottom surface and directed in the front-rear direction, and a front-rear direction formed on the upper surface of the base (3). The close fitting with the groove (3a) restricts the movement in the left-right direction, and long holes (8) are formed in the left and right sides of the base (3) and are long in the front and rear.
By loosening a pair of left and right fixing bolts (9) screwed into the bottom surface of the support block (7) from below (8), the above-mentioned concave groove is formed.
Guided by (3a), it can slide in the front-back direction.

A work holder (10) is attached to the inclined surface (7a) of the support block (7).

As shown in FIG. 2, the work holder (10) has a ridge (10a) formed in the central portion of the bottom surface and directed in the front-rear direction, and the inclined surface (7
It is slidable in the front-rear direction by tightly fitting the groove (11) provided in a) facing the front-rear direction.

As described above, by restricting the support block (7) and the work holder (10) in the left-right direction with the protrusions (7b) (10a) and the concave grooves (3a) (11), respectively, If the central axis of the probe (5) and the central axis of the shaft portion of the work to be described later are made to coincide with each other, even when the support block (7) and the work holder (10) are moved, the It is possible to prevent the central axis line from shifting in the left-right direction.

Insert the bolts (12) inserted from above the long holes (13) in the front-rear direction provided in the sideward-facing flanges (10b) (10b) that are connected to the lower part of the work holder (10) into the support block (7). The work holder (10) is fixed by screwing it onto the inclined surface (7a) of FIG.

The upper part of the work holder (10) is provided with a downwardly inclined shaft hole (14) concentric with the shaft hole (6b) formed in the mounting portion (6a) of the probe holder (6). Has been done.

A cylindrical work guide (15) having a guide hole (15a) in the center is fitted into the shaft hole (14), and the bolts (16) and (16) inserted from the upper surface of the work holder (10) pull it out. It has been stopped.

The upper open end of the guide hole (15a) is chamfered in a tapered shape to facilitate insertion of the shaft portion (17a) of the engine valve (17), which is a work.

A female screw hole (18) whose central axis intersects with the central axis of the work guide (15) above is formed in the intermediate portion of the work holder (10), that is, immediately below the shaft hole (14). A stopper bolt (19) is inserted through the female screw hole (18).

Insert the stopper bolt (19) into the shaft (17) of the engine valve (17).
The reason for being inclined with respect to a) is as follows.

That is, the valve face (F) formed on the umbrella portion (17b) has an important function of closing the intake / exhaust port and sealing the gas, so that the surface thereof has good adhesion to the valve seat. Therefore, various surface treatments and precision processing have been performed.

If the stopper bolt (19) is provided parallel to the shaft portion (17a), when the size of the umbrella portion (17b) is changed by the engine valve (17), the stopper bolt (19) abuts against the back of the umbrella. The position is not constant, and particularly when the umbrella diameter is small, there is a risk of contact with the valve face (F) and causing dents or scratches.

However, when the stopper bolt (19) is tilted, the protrusion length of the stopper bolt (19) or the position of the work holder (10) is changed, so that the stopper bolt (19) can be moved within a certain range of the umbrella diameter.
The upper end of (19) can be brought into constant contact with the neck portion (N) that has not been surface-treated.

The engine valve (17) inserted into the guide hole (15a) of the work guide (15) from above is fixed and held by contacting the lower surface of the umbrella portion (17b) with the upper end of the stopper bolt (19).

In this case, the dimension between the tip surface of the shaft portion (17a), that is, the tip surface of the tip (17c) of the martensite system welded to the shaft end and the probe (5) is set to a predetermined dimension. There is a need to. For this adjustment, first, the work holder (10) may be slid to obtain its approximate size, and then the protruding length of the stopper bolt (19) may be adjusted.

Next, the centering procedure of the jig will be described with reference to FIG.

As mentioned above, support block (7) and work holder (10)
Is blocked from moving in the left-right direction.
Since the central axes of (5) and the shaft portion (17a) of the workpiece coincide with each other in the left-right direction, it is only necessary to align the centers in the front-back direction.

After temporarily fixing the work holder (10) to an appropriate position on the support block (7), remove the work guide (15) and the stopper bolt (19) from the work holder (10), and from the probe holder (6). Remove the probe (5).

Next, loosen the fixing bolt (9) of the support block (7), and then
Shaft (20) that can be closely fitted with the shaft hole (14) of the work guide (15)
a) and a shaft part (20b) of a slightly smaller diameter that is connected to the tip part of the shaft part (20a) and that can fit tightly into the shaft hole (6a) of the probe holder (6).
The centering rod (20) having the above is inserted into the shaft hole (14) obliquely above the work holder (10).

At the same time, slide the support block (7) back and forth to align the shaft (20b) with the shaft hole (6a), and then until the shaft (20b) penetrates the shaft hole (6a). insert.

In this state, the support block (7) is fixed and the centering rod (20) is pulled out.

Finally, when the probe (5), the work guide (15) and the stopper bolt (19) are attached, the centering work is completed.

As a result, the shaft center (17a) of the engine valve (17) set in the work guide (15) and the axial center of the probe (5) are exactly aligned, and the shaft for the probe (5) is aligned. The squareness of the end face of the part (17a) is maintained. Therefore, with high flaw detection accuracy,
It is possible to measure the internal defect of the welded portion (W) in the tip (17c).

Once centered according to the above procedure, the work guide (15) can be used even if the shaft diameter changes depending on the type of work.
It is not necessary to perform centering again only by replacing the work piece, and by moving the work holder (10) or the stopper bolt (19), the distance between the probe (5) and the shaft part (17a) can be reduced. Even when adjusted to a predetermined size, there is no risk of misalignment with each other.

As described above, in this embodiment, the work holder (1
(0) is provided on the inclined surface (7a) of the support block (7) in an inclined manner, so that the shaft end of the probe (5) and the engine valve (17) can be submerged in the water tank (2). When water is sprinkled on the upper surface of the guide hole (15a), the non-inspection side of the work, and the upper end side of the stopper bolt (19) are exposed from the water surface (2a).

Therefore, the replacement work of the engine valve (17) and the adjustment of the protruding length of the stopper bolt (19) can be performed easily and quickly without wetting with a hand.

The present invention is not limited to the above embodiment, but can take various forms.

For example, when the diameter of the shaft portion (17a) of the work is constant, the work holder (10) is directly provided with a guide hole for holding the shaft portion (17a), and the work guide (15) is omitted. There are also things to do.

If the dimension between the probe (5) and the workpiece shaft end can be adjusted to the specified dimension by adjusting only the stopper bolt (19), remove the support block (7) and place the workpiece on the base (3). Holder (10)
May be slidably mounted.

The inclination angle of the work holder (10) is arbitrary except vertical. The reason why it is not vertical is that bubbles generated by the ultrasonic waves from the probe (5) may adhere to the shaft end of the probe or the work and adversely affect the flaw detection accuracy.

[Effect of the Invention] According to the present invention, the operator does not have to put his / her hand in the water when exchanging the work, and since the exchanging work can be performed while visually checking the holding hole, the workability is improved and the inspection work is efficiently performed. To be the target.

If the work holder is attached to the support block so as to be vertically movable, the range of adjustment of the dimension between the probe and the work shaft end is expanded, and the length of the work shaft portion can be accommodated.

When the work guide is provided in the work holder, only the work guide needs to be replaced when the shaft diameter of the work is changed, and at this time, there is no risk of misalignment between the probe and the work shaft portion.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of the present invention, FIG. 2 is a vertical sectional front view of a main part taken along line XX in FIG. 1, and FIG. FIG. 4 is a side elevational view showing a centering state of the jig of the present invention, and FIG. (1) jig, (2) water tank (3) base, (3a) (11) groove (4) (9) (12) (16) bolt, (5) probe (6) probe Holder, (6b) (14) Shaft hole (7) Support block, (7a) Inclined surface (7b) (10a) Ridge, (8) (13) Long hole (10) Work holder, (10b) Flange ( 15) Work guide, (15a) Guide hole (17) Engine valve, (17a) Shaft part (17b) Umbrella part, (17c) Tip (18) Female screw hole, (19) Stopper bolt (20) Centering rod, (20a) (20b) Shaft (F) Valve face, (N) Neck (W) Weld

Claims (3)

[Scope of utility model registration request] 1. A jig for water immersion type ultrasonic flaw detection performed by immersing a portion to be inspected of a probe and a work in water, the probe having a shaft hole for holding the probe. The child holder and the work holder having a shaft hole for holding the shaft portion of the work are arranged such that the axis lines of the shaft holes are obliquely aligned vertically and are aligned with each other, and at least the upper end of the shaft hole of the work holder. Is provided on a proper base so that at least one of them is exposed from the water surface and can be moved, and a water immersion type ultrasonic flaw detection jig. 2. The work holder shaft hole is provided in a work guide detachably provided in the work holder.
The water immersion type ultrasonic flaw detection jig described in (1). 3. A work holder is provided on a downwardly inclined surface parallel to an axial hole in a support block provided movably on a base,
The device is mounted so that it can move in an obliquely vertical direction.
The water immersion type ultrasonic flaw detection jig according to (1) or (2).