JP2012127658A - Flaw detection method of motor fixing bolt of jet fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that it is necessary to periodically perform inspection such as the existence of cracks on a motor fixing bolt for a jet fan arranged on the ceiling of a road tunnel, capable of rotating at a high speed and subjected to exhaust gas of automobiles or the like, and a snow melting agent or the like, but the inspection work of the large-sized jet fan arranged on the ceiling of the tunnel is extremely difficult.SOLUTION: A method capable of surely and quickly inspecting the motor fixing bolt in a state that the jet fan is attached to the ceiling of the tunnel is provided. In the method, a bolt polishing tool 5a composed of a rod-like trunk part 1, a milling machine 2a attached to the tip of the trunk part 1 and an operation lever 4 attached to the other end is used. The bolt polishing tool 5a is inserted from an outlet or a suction port of the jet fan, the operation lever 4 is operated on the outlet or the suction port to plane the head of the motor fixing bolt, and then flaw detection operation is performed.

Description

  The present invention relates to a flaw detection method for a motor fixing bolt of a jet fan attached to a ceiling inside a tunnel.

  Metallic bolts that have been used for a long period of time may cause problems due to corrosion in the form of use. In particular, for a jet fan that is provided on the ceiling inside the tunnel, rotates at a high speed, and is exposed to an exhaust gas or a snow melting agent of an automobile or the like, it is necessary to periodically check the motor fixing bolt. The structure of such a jet fan will be described with reference to FIG. The jet fan 101 includes a cylindrical main body 102 having a total length of several meters, an electric motor 103 provided at the center thereof, and an axial flow type impeller 104. In FIG. 4, the electric motor 103 is a double-shaft type so that air can be blown to either the front or rear side of the jet fan 101, and an axial-flow impeller 104 is attached to both of them. The two impellers 104 are mounted in opposite directions so that the jet fan 101 can obtain the same performance in both the front and rear directions. The main body 102 of the jet fan 101 is supported by several front and rear supports (not shown) at the center in the axial direction, and the front and rear silencing cylinders 102a having the silencing cylinder hub 107 for adjusting the air path and the motor 103 are fixed. It is comprised by the cylinder 102b. The electric motor 103 is assembled by a motor fixing bolt 106 to a pedestal 105 fixed inside the blower cylinder 102b.

  In the inspection of the electric motor fixing bolt 106, the jet fan 101 attached to the ceiling inside the tunnel is lowered by a lifter or the like, moved to a work place, and the muffler cylinder 102a is further removed. As for flaw detection of the motor fixing bolt 106, as described in Patent Document 1 below, the probe surface of the ultrasonic probe must be brought into close contact with the surface of the object to be measured.

JP 2004-77234 A

  In such a method of checking the motor fixing bolt of the jet fan 101, there is a problem that the jet fan 101 having a total length of several meters fixed to the ceiling inside the tunnel must be taken down from the ceiling and disassembled. In addition, there is a problem that on-site inspections are surely performed in a period determined by traffic restrictions.

  Accordingly, the present invention solves such a conventional problem, and in the method for inspecting the motor fixing bolt of a jet fan used in a tunnel, the motor fixing bolt is inspected while the jet fan is attached to the ceiling inside the tunnel. An object of the present invention is to provide a method capable of reliably performing the process in a short time.

  In order to achieve this object, the present invention relates to a method for flaw detection of an electric motor fixing bolt of a jet fan provided with a blower cylinder and a muffler cylinder, a rod-shaped body, a milling machine provided at the tip thereof, and the like. Using a bolt polishing jig composed of an operation part provided at the end, this bolt polishing jig is inserted from the outlet or suction port of the jet fan, and the operation part is operated at the outlet or suction port to fix the motor. This is a method for flaw detection of an electric motor fixing bolt of a jet fan that performs flaw detection after the bolt head is flattened, thereby achieving the intended purpose.

  According to the present invention, in a flaw detection method for an electric motor fixing bolt of a jet fan provided with a blower cylinder and a muffler cylinder, a rod-shaped body part, a milling machine provided at the tip thereof, and an operation part provided at the other end After using the configured bolt polishing jig, the bolt polishing jig is inserted from the outlet or suction port of the jet fan, and the operation unit is operated at the outlet or suction port to flatten the head of the motor fixing bolt. By the flaw detection method of the motor fixing bolt of the jet fan that performs the flaw detection work, the bolt head can be made flat by operating it from a remote position, and the probe of the ultrasonic flaw detector can be brought into close contact with the bolt head. In addition, it is possible to obtain an effect that the internal fracture state can be diagnosed in a short time.

Schematic of the bolt grinding jig of Embodiment 1 of the present invention Schematic of bolt grinding jig using the counterbore machine Schematic diagram of the flaw detection jig (A) Overall view, (B) Cross section of the probe Sectional view showing configuration of jet fan

  According to a first aspect of the present invention, there is provided a method for flaw detection of an electric motor fixing bolt for a jet fan, comprising: a rod-shaped body portion; a milling machine provided at a tip thereof; A bolt polishing jig composed of an operating part provided, and the bolt polishing jig is inserted from an outlet or a suction port of the jet fan, and the operation part is operated at the outlet or the suction port to fix the electric motor fixing bolt. This is a method for flaw detection of motor fixing bolts for jet fans that perform flaw detection after the head is flattened, and even if the jet fan with a total length of several meters is taken down from the tunnel and not disassembled, inspection of the motor fixing bolts is ensured. In addition, the flaw detection work can be realized in a short time.

  In addition, the particle size of the milling machine can be changed so that inspection of the motor fixing bolts can be performed in a short period of time without having to take down a jet fan with a total length of several meters from the tunnel and disassemble it. It has the effect of being possible.

  In addition, a bolt polishing jig composed of a rod-shaped body, a counterbore processing machine provided at the tip thereof, and an operation part provided at the other end is used, and the bolt polishing jig is connected to the jet fan outlet or suction port. After inserting from the mouth and operating the operation section at the blowout or suction port to flatten the head of the motor fixing bolt only on the surface where the probe of the ultrasonic flaw detector contacts, Even if the jet fan having a total length of several meters is taken down from the tunnel and not disassembled, the inspection of the electric motor fixing bolt can be surely performed in a short time.

  In addition, after flattening the bolt head, a gel sealant is applied to the bolt head, and an ultrasonic flaw detector is used to search for scratches in the bolt. A jet fan with a total length of several meters is lowered from the tunnel and disassembled. Even if it is not, it has the effect that the flaw detection work can be realized in a short time surely checking the motor fixing bolt.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
As shown in the prior art (FIG. 4), the jet fan 101 is composed of a cylindrical main body 102 having a total length of several meters, an electric motor 103 provided at the center thereof, and an axial flow type impeller 104. The This jet fan 101 is provided with a double-shaft type electric motor 103 so that air can be blown to both the front and rear sides, and an axial flow type impeller 104 is attached to both ends of the shaft. The two impellers 104 are mounted in opposite directions so that the jet fan 101 can obtain the same performance in both the front and rear directions. The main body 102 of the jet fan 101 includes a blower cylinder 102b to which the electric motor 103 is fixed, and a silencer cylinder 102a that is provided at the front and rear of the blower cylinder 102b and has a silencer cylinder hub 107 supported by several supports at the center of the shaft. ing. The electric motor 103 is assembled to a pedestal 105 fixed inside the blower cylinder 102b with an electric motor fixing bolt 106 and a nut. The electric motor fixing bolt 106 that requires flaw detection work is located at the center of the long silencer cylinder 102a. For the flaw detection of the motor fixing bolt 106, it is first necessary to flatten the head of the motor fixing bolt 106. In order to flatten the head of the motor fixing bolt 106 without disassembling the jet fan 101, a bolt polishing jig 5a as shown in FIG. 1 is used. The bolt polishing jig 5a is composed of a rod-shaped body portion 1, a milling machine 2a provided at the tip thereof, and an operation lever 4 serving as an operation portion provided at the other end. The power cord 3 of the milling machine 2 a is housed in the body 1. Next, a method of using the bolt polishing jig 5a will be described.

  As described above, the motor fixing bolt 106 that is to be examined for the presence or absence of scratches is located in the central portion away from the end opening of the jet fan 101. First, the tip of the bolt grinding jig 5a on the milling machine 2a side is passed between the inner surface of the muffler cylinder 102a and the muffler cylinder hub 107 and the gap of the impeller 104, and the milling machine 2a is placed on the head of the motor fixing bolt 106. Try to apply. At that time, the position is determined so that the milling machine 2a is in contact with the head surface of the motor fixing bolt 106 in parallel. In this state, the operation lever 4 is operated to process the head of the motor fixing bolt 106 into a flat surface. That is, by such a method, the head of the motor fixing bolt 106 can be polished in a short time without disassembling the jet fan 101.

  In addition, the milling machine 2a changes the grain size of the milling machine 2a according to the corrosion of the bolt head of the motor fixing bolt 106 and the state of deposits, selects an appropriate grain size, and makes the motor fixing bolt head flat. Can be checked reliably in a short time.

  Moreover, as shown in FIG. 2, it is good also as the bolt grinding | polishing jig | tool 5b which used the counterbore processing machine 2b at the front-end | tip. In the counterbore machine 2b, the tip has a flat cutting surface with a tip angle of 180 °, and the body has a spiral groove so that chips are discharged to the outside. According to the counterbore machine 2b, when the head of the motor fixing bolt 106 is cut, only a part of the bolt head of the motor fixing bolt 106 that is in contact with the probe 13a of the ultrasonic flaw detector 13 can be planarized. It becomes. Therefore, the motor fixing bolt 106 can be inspected reliably in a short time.

  Next, a flaw detection operation is actually performed using the flaw detection jig 11 shown in FIG. This flaw detection jig 11 is composed of a rod-shaped body 12 and an arm divided into two at the tip. One of the arms is a probe arm 14 to which the probe 13a of the ultrasonic flaw detector 13 is attached. The other arm is a support arm 15 for pressing the measurement location of the object to be measured (fixing bolt) with the probe arm 14. The tip of the probe arm 14 can be rotated by providing an axis perpendicular to the body 12. A probe 13a is provided at the rotating portion. The probe 13 a has its contact surface facing the arm 15. The probe arm 14 and the support arm 15 are provided on the proximal side of the body 12 so as to sandwich the object to be measured in order to press the probe 13a against the measurement position of the object to be measured (the motor fixing bolt 106). The operation lever 16 can be opened and closed.

  A method for flaw detection of the motor fixing bolt 106 by the flaw detection jig 11 having such a configuration will be described.

  The tip of the flaw detection jig 11 is applied to the motor fixing bolt 106 to be checked for the presence of scratches, the probe arm 14 is applied to the head side of the motor fixing bolt 106, and the support arm 15 is applied to the screw portion side or the nut side. . Next, the operation lever 16 is operated to close the probe arm 14 so that the motor fixing bolt 106 is grasped. The tip of the probe arm 14 is pivotably provided, and when the contact surface of the probe 13a contacts the head of the motor fixing bolt 106, the operation lever 16 is completely closed. Since the gel-like sealing agent 21 is applied to the contact surface of the probe 13a, the gel-like sealing agent 21 comes into close contact with the head of the motor fixing bolt 106. Accordingly, the gel-like sealant 21 is kept in a state where a slight uneven portion on the surface of the head of the motor fixing bolt 106 is filled, and it is easy for the probe 13a and the head of the motor fixing bolt 106 to contact each other vertically. Become.

  In this state, by operating the ultrasonic flaw detector 13 to perform the flaw detection inspection of the motor fixing bolt 106, the inspection of the motor fixing bolt 106 that is out of reach can be surely performed in a short time. .

  According to the present invention, in a flaw detection method for an electric motor fixing bolt of a jet fan provided with a blower cylinder and a muffler cylinder, a rod-shaped body part, a milling machine provided at the tip thereof, and an operation part provided at the other end After using the configured bolt polishing jig, the bolt polishing jig is inserted from the outlet or suction port of the jet fan, and the operation unit is operated at the outlet or suction port to flatten the head of the motor fixing bolt. By the flaw detection method of the motor fixing bolt of the jet fan that performs the flaw detection work, the bolt head can be made flat by operating it from a remote position, and the probe of the ultrasonic flaw detector can be brought into close contact with the bolt head. In addition, it is possible to obtain an effect that the internal fracture state can be diagnosed in a short time. Therefore, it is useful for inspection of a jet fan provided on the ceiling inside the tunnel, that is, for flaw detection of a fixing bolt for fixing an electric motor.

DESCRIPTION OF SYMBOLS 1 Body part 2a Milling machine 2b Counterbore processing machine 3 Power supply cord 4 Operation lever 5a Bolt grinding jig 5b Bolt grinding jig 11 Flaw detection jig 12 Body 13 Ultrasonic flaw detector 13a Probe 14 Probe arm 15 Support arm 16 Operation lever 21 Sealing agent 101 Jet fan 102 Main body 102a Muffler cylinder 102b Blower cylinder 103 Electric motor 104 Impeller 105 Base 106 Motor fixing bolt 107 Muffler hub

Claims (4)

In the flaw detection method of the motor fixing bolt of the jet fan equipped with the blower cylinder and the muffler cylinder,
Using a bolt grinding tool composed of a rod-shaped body, a milling machine provided at the tip, and an operation part provided at the other end, the bolt grinding tool is inserted from the jet fan outlet or suction port. A method for flaw detection of a motor fixing bolt of a jet fan in which flaw detection is performed after the operation unit is operated at the air outlet or suction port to flatten the head of the motor fixing bolt. The method for flaw detection of an electric motor fixing bolt of a jet fan according to claim 1, wherein a particle size of the milling machine can be changed. In a flaw detection method for an electric motor fixing bolt of a jet fan equipped with a blower cylinder and a muffler cylinder, a bolt polishing composed of a rod-shaped body, a counterbore machine provided at the tip thereof, and an operation part provided at the other end Using a jig, insert the bolt polishing jig from the blower outlet or suction port of the jet fan, and operate the operation unit at the blowout port or suction port to connect the head of the motor fixing bolt to the probe of the ultrasonic flaw detector. A method for flaw detection of a motor fixing bolt for a jet fan in which only the contact surface is flattened with a spot facing machine and then flaw detection is performed. After making the bolt head flat, apply a gel sealant to the bolt head,
The flaw detection method for a motor fixing bolt for a jet fan according to any one of claims 1 to 3, wherein a flaw in the bolt is searched with an ultrasonic flaw detector.

Images