CN106197487A - A kind of sensor of miter gate's crackle on-line detecting system and preparation method thereof - Google Patents

Abstract

The invention discloses a sensor of an on-line crack detection system for a miter door and a manufacturing method thereof. The sensor includes two rigid protection boxes and optical fibers. There are multiple optical fibers arranged between the two rigid protection boxes. ; The rigid protection box is circular, and a plurality of circular small optical fiber discs with a diameter of m distributed around it and a large circular optical fiber disc with a diameter of n at the center are fixed inside it, and the large optical fiber disc is used for auxiliary Fix the fiber. The present invention can realize crack detection in one area by using multiple sensors and one OTDR module, which greatly reduces the number of channels of the OTDR module, thereby reducing the complexity and cost of building the entire detection system. The sensor designed by the present invention effectively utilizes optical fiber resources, so that multi-point detection of cracks can be realized through one optical fiber, which is not only efficient and fast, but also saves space occupation compared with the conventional detection method of laying optical fibers.

Description

A sensor for an online detection system for cracks in a miter door and its manufacturing method

technical field

The invention relates to the technical field of health detection of hydraulic metal structures, in particular to a sensor manufacturing method of an online crack detection system for a miter door.

Background technique

The structural robustness of the miter gate of the ship lock is always faced with challenges during its working process, among which the huge water pressure difference on both sides of the miter gate, the extrusion of the water flow during the opening and closing of the miter gate will cause structural damage and deformation of the gate body, etc. The problem will cause cracks in the stress concentration area of the door body under long-term action, and affect the long-term reliable operation of the ship lock.

The traditional crack detection method is to use an optical time domain reflectometer (OTDR) to arrange an optical fiber at a certain angle to the expected crack. It can detect a crack. When testing a large area, there are disadvantages such as occupying space and wasting fiber resources, and the crack-prone areas on the miter gate are relatively scattered. Using this method to build a system requires an additional increase in the number of channels of the OTDR module , which greatly increases the complexity and cost of system construction, and brings difficulties to subsequent signal processing.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the present invention designs a sensor for an online detection system for miter gate cracks and a manufacturing method thereof that can save optical fiber resources and reduce the complexity and cost of system construction.

In order to achieve the above object, the technical solution of the present invention is as follows: a sensor of an online detection system for miter door cracks, including two rigid protective boxes and optical fibers, and there are multiple optical fibers arranged between the two rigid protective boxes ; The rigid protective box is circular and has a diameter of d, and a plurality of windows are opened on the side, and a plurality of circular small optical fiber discs with a diameter of m distributed around and a circle with a diameter of n at the center are fixed inside it Shaped large optical fiber tray, the large optical fiber tray is used to assist in fixing the optical fiber;

The diameter d of the rigid protective box, the diameter m of the small optical fiber disc, and the diameter n of the large optical fiber disc satisfy the following formula:

d=n+2m+a, where a is a constant, the value is 6-8cm;

The structure and size of the two rigid protective boxes are exactly the same, namely the rigid protective box A and the rigid protective box B.

Further, the two rigid protective boxes and the optical fiber are fixed on the surface of the miter gate.

A method for manufacturing a sensor for an on-line crack detection system for a miter door, comprising the following steps:

A. On both sides of the crack detection area of the miter door, respectively fix the rigid protection box A and the rigid protection box B, introduce the optical fiber into the rigid protection box A, and wind several turns on the large optical fiber disc of the rigid protection box A and fix it;

B. Lead the optical fiber into a small optical fiber reel in the rigid protective box A and wind it around i circles, where the value of i satisfies the following formula:

$\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; N</span>}\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; p</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; )</span>$

Wherein, p is the size of the event dead zone in order to demodulate the OTDR module, and m is the diameter of the small optical fiber dish;

Then lay the optical fiber on the crack detection area, and temporarily install a cylindrical base to assist in fixing the optical fiber, and then introduce the optical fiber into the rigid protection box B; the direction of the optical fiber in the crack detection area is oblique to the crack occurrence direction at an angle of 60 to 70 degrees;

C. First wrap i circles on the small fiber optic disc in rigid protection box B, then introduce it to the large fiber optic disc in rigid protection box B and wind several turns and fix it, and then pass through another small fiber optic disc in rigid protection box B Wrap i circles on the top, and finally lay the optical fiber on the crack detection area, and temporarily install a cylindrical base to assist in fixing the optical fiber, and then reintroduce the optical fiber into the rigid protection box A; the direction of the optical fiber in the crack detection area is parallel to the previous optical fiber;

D. Repeat steps B to C several times according to the layout requirements of the crack detection area, and lead the optical fiber out of the rigid protection box A.

Compared with prior art, the beneficial effect of the present invention is:

1. Compared with the traditional crack detection method, the present invention can detect cracks in an area by using multiple optical fiber crack sensors and one OTDR module, which greatly reduces the number of channels of the OTDR module, thus reducing the cost of building the entire detection system. complexity and cost.

2. The optical fiber crack sensor designed by the present invention effectively utilizes optical fiber resources, so that multi-point detection of cracks can be realized through a single optical fiber. Compared with the conventional detection method of laying optical fibers, it is not only efficient and fast, but also saves space. occupy.

Description of drawings

The present invention has 1 accompanying drawing, wherein:

Figure 1 is a schematic diagram of the internal structure of an optical fiber crack detection sensor.

In the figure: 1. Rigid protection box A, 2. Rigid protection box B, 3. Large fiber optic disk A, 4. Large fiber optic disk B, 5. Small fiber optic disk A, 6. Small fiber optic disk B, 7. Small fiber optic disk C, 8, small optical fiber disc D, 9, cylindrical base A, 10, cylindrical base B, 11, cylindrical base C, 12, cylindrical base D, 13, optical fiber input end, 14, optical fiber output end.

detailed description

The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings: It should be understood that the preferred embodiments are only for illustrating the present invention, rather than limiting the protection scope of the present invention.

The technical scheme adopted by the present invention is: the interior of the rigid protection box is composed of a large optical fiber disc located at the center of the circle and a small optical fiber disc located near the circumference, and there are multiple windows on the side, the large optical fiber disc plays a preliminary fixing role, and the small optical fiber disc is used for Wind and lead out the optical fiber, fix a rigid protective box on both sides of the crack detection area, and use the following method to lay out the optical fiber at a specific angle.

As shown in Figure 1, the sensor of the online detection system for miter door cracks includes two circular rigid protection boxes A1 with multiple windows on the sides, rigid protection box B2 and optical fibers. A small fiber optic disk with a minimum inner diameter of 3cm and a large fiber optic disk with a minimum inner diameter of 6cm located in the center. The large fiber optic disk is used to assist in fixing the optical fiber. The diameter d of the rigid protective box is calculated by the formula d=n+2m+a, where If a is selected as 8cm, d=20cm can be obtained.

A sensor manufacturing method for an online detection system for miter door cracks, the steps are:

A. On both sides of the crack detection area, fix the rigid protection box A1 and the rigid protection box B2 respectively, introduce the optical fiber from the optical fiber input end 13 into the rigid protection box A1 and wind several turns on the large optical fiber disk A3 and fix it;

B. Lead the optical fiber into the small optical fiber reel A5 and wind it around i circles, where i is calculated by the following formula:

$\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; N</span>}\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; p</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; )</span>$

Among them, p is selected as 6m according to the actual situation, m is selected as 3cm, and i=63 is obtained through calculation; then the optical fiber is laid on the crack detection area, and the cylindrical base A9 and cylindrical base B10 are temporarily installed to assist in fixing the optical fiber, and then the The optical fiber is introduced into the rigid protective box B2;

C. First wind 63 turns on the small fiber optic reel C7, then pull it to the large fiber optic reel B4 and wrap several turns and fix it, then wind 63 turns on the small fiber optic reel D8, and then lay the optical fiber on the crack detection area, and temporarily Install the cylindrical base C11 and the cylindrical base D12 to assist in fixing the optical fiber, and introduce the optical fiber into the rigid protective box A1; wrap 63 turns on the small optical fiber reel B6, then pull it to the large optical fiber reel A3, wind several turns and fix it;

D. Repeat steps B to C several times according to the layout requirements of the detection area, and lead the optical fiber out of the rigid protection box A1 from the optical fiber output end 14 .

In addition, the optical fiber between the rigid protection box A1 and the rigid protection box B2 is obliquely fixed at an angle of 60-70 degrees to the crack occurrence direction in the crack detection area.

The present invention is not limited to this embodiment, and any equivalent ideas or changes within the technical scope disclosed in the present invention are listed in the protection scope of the present invention.

Claims (3)

1. The sensor of a miter gate crack on-line detection system is characterized in that: it comprises two rigid protective boxes and optical fibers, and said optical fiber has many, is arranged between two rigid protective boxes; said rigid protective box The box is circular with a diameter of d, and multiple windows are opened on the side, and a plurality of circular small optical fiber disks with a diameter of m distributed around and a large circular optical fiber disk with a diameter of n in the center are fixed inside the box. The optical fiber tray is used to assist in fixing the optical fiber; The diameter d of the rigid protective box, the diameter m of the small optical fiber disc, and the diameter n of the large optical fiber disc satisfy the following formula: d=n+2m+a, where a is a constant, the value is 6-8cm; The structure and size of the two rigid protective boxes are exactly the same, namely the rigid protective box A (1) and the rigid protective box B (2). 2. The sensor of an on-line crack detection system for a miter door according to claim 1, wherein the two rigid protective boxes and optical fibers are fixed on the surface of the miter door. 3. A method for making a sensor of a miter gate crack on-line detection system, characterized in that: comprising the following steps: A. Fix the rigid protection box A (1) and the rigid protection box B (2) on both sides of the crack detection area of the miter door respectively, lead the optical fiber into the rigid protection box A (1), and insert the optical fiber into the rigid protection box A (1) ) on a large optical fiber disc and fix it by winding several circles; B. Lead the optical fiber into a small optical fiber disc in the rigid protective box A (1) and wind it around i circles, where the value of i satisfies the following formula: $\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; I</span>}\mathrm{<span\; class="notranslate">\; N</span>}\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; p</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; )</span>$ Wherein, p is the size of the event dead zone in order to demodulate the OTDR module, and m is the diameter of the small optical fiber dish; Then lay the optical fiber on the crack detection area, and temporarily install a cylindrical base to assist in fixing the optical fiber, and then introduce the optical fiber into the rigid protection box B (2); the direction of the optical fiber in the crack detection area is at an angle of 60 to 70 degrees to the crack occurrence direction oblique; C. First wrap i circles on the small optical fiber disc in the rigid protection box B (2), then introduce it into the rigid protection box B (2) and wind several circles on the large optical fiber disc and fix it, and then pass through the rigid protection box B ( 2) Wrap i circles on another small optical fiber reel, and finally lay the optical fiber on the crack detection area, and temporarily install a cylindrical base to assist in fixing the optical fiber, and then reintroduce the optical fiber into the rigid protection box A (1); the optical fiber The direction in the crack detection area is parallel to the previous optical fiber; D. Repeat steps B to C several times according to the layout requirements of the crack detection area, and lead the optical fiber out of the rigid protection box A (1).