JP2022166345A - Leakage prevention device, water leakage prevention method, construction method for water leakage prevention device and valve - Google Patents

Abstract

A water leakage prevention device, a water leakage prevention method, a water leakage prevention device installation method, and a valve are provided, which enable repair of a valve due to water leakage from a shaft seal fixing portion of the valve without water interruption in a pipeline. A fixed portion water leakage prevention tool 30 includes a valve stem 14, a gland packing 20 disposed around the valve stem 14 and sealing the outer peripheral surface of the valve stem 14, a packing box 13 accommodating the gland packing 20, a gland In the geared gate valve 10 provided with a packing retainer 23 for pressing the packing 20 from above, a seal member 31 abutting on the upper surface 13d of the packing box 13 and the lower surface 23d of the packing box 23 over the entire circumference is attached to the packing box. 13 and the lower surface 23d of the packing retainer 23, water leakage from between the outer peripheral surface of the gland packing 20 and the inner peripheral surface of the packing box 13 is prevented. [Selection drawing] Fig. 1

Description

The present invention comprises a water leakage prevention device for preventing water leakage from a shaft seal fixing portion of a valve, a valve water leakage prevention method using the water leakage prevention device, a method for installing the water leakage prevention device to the valve, and the water leakage prevention device. Regarding valves.

Conventionally, there is a gate valve as shown in Patent Document 1, for example, as a valve for which this type of water leakage prevention tool is used. The sluice valve of Patent Document 1 is a sluice valve provided for each doorway of a water pipe, and is connected to the water pipe inside a valve housing. The sluice valve is mainly composed of a valve body, a packing box, and a packing retainer. In the gate valve, a valve stem, which is connected to a valve body in the valve body, is provided in a state of protruding from the valve body so as to be operated by being connected to an external operating means (for example, a rotating handle).

In the gate valve, the gland packing is accommodated in the packing box, and a fastening member (for example, a bolt and a nut) that connects the packing box and the packing retainer is tightened to press the gland packing from above by the packing retainer. Prevents water leakage between the valve stem and packing gland. In addition, in the above gate valve, if water leakage occurs from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box (fixed part of the shaft seal of the valve) due to deterioration of the gland packing over time, etc. Such leakage is prevented by further tightening the member to adjust the pressure exerted by the gland.

Japanese Patent Publication No. 5-67836

However, in the gate valve of Patent Document 1, if water leakage from the shaft seal fixing portion of the valve due to aged deterioration of the gland packing cannot be prevented by tightening the fastening member, the deteriorated gland packing can be replaced and the water leakage can be prevented. However, in order to replace the deteriorated gland packing, it is necessary to cut off the water supply to the pipeline. Therefore, there is a problem that the pipeline cannot be used while the valve is being repaired due to water leakage from the fixing portion of the shaft seal of the valve.

The present invention provides a leak preventive device, a leak preventive method, a method for installing the leak preventive device, and a valve that can repair a valve due to water leakage from a shaft seal fixing portion of the valve without water interruption in the pipeline. for the purpose.

In order to achieve the above object, the water leakage prevention tool of the present invention comprises a valve stem, a gland packing arranged around the valve stem and sealing the outer peripheral surface of the valve stem, a packing box accommodating the gland packing, a packing retainer for pressing the gland packing from above, wherein a sealing member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference is arranged on the upper surface of the packing box and the packing retainer. prevents water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box between the upper surface of the packing box and the lower surface of the packing retainer. It is.

According to this, by arranging the seal member between the upper surface of the packing box and the lower surface of the packing retainer, water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box is prevented. The leakage can be easily prevented without removing the Therefore, the water leakage can be prevented without shutting down the pipeline.

In the water leakage prevention tool of the present invention, in the valve provided with a plurality of fastening members that fasten the packing box and the packing retainer, the sealing member is configured to be divisible by the same number of split seal pieces as the fastening members, The split seal piece has a hole through which the fastening member can be inserted, and is fixed between the upper surface of the packing box and the lower surface of the packing retainer by the fastening member inserted through the hole. should be

According to this, the seal member is composed of the same number of split seal pieces as the fastening members, and the split seal pieces are fixed between the top surface of the packing box and the bottom surface of the packing retainer by fastening members inserted through the holes. Therefore, the split seal piece can be fixed or removed between the packing box and the packing presser for each fastening member that fastens the packing box and the packing presser. Therefore, the seal member can be attached and detached without releasing the pressure of the packing retainer on the gland packing while the packing retainer is attached.

In the water leakage preventive device of the present invention, the split seal piece tightens the packing box and the packing retainer by the fastening member inserted through the hole, so that the upper surface of the packing box and the lower surface of the packing retainer are separated. It is preferable that it is tightened between them.

According to this, it is possible to adjust the pressure of the packing presser on the gland packing and adjust the pressure of the packing presser on the seal member by tightening the fastening member.

In the water leakage prevention device of the present invention, the sealing member has a core metal and an elastic material lined on the core metal, and the elastic material contacts the upper surface of the packing box and the lower surface of the packing retainer. It should be in contact.

According to this, since the elastic material lined on the core metal contacts the top surface of the packing box and the bottom surface of the packing retainer, the outer peripheral surface of the gland packing can be and the inner peripheral surface of the packing box can be reliably prevented from leaking.

The water leakage prevention method of the present invention includes a valve stem, a gland packing arranged around the valve stem and sealing the outer peripheral surface of the valve stem, a packing box containing the gland packing, and pressing the gland packing from above. and a packing retainer for preventing water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box in a valve in which the packing box and the packing retainer are fastened by a plurality of fastening members. The water leakage prevention method includes a seal member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference, and the seal member is configured to be divisible by the same number of split seal pieces as the fastening members. The packing box and the packing retainer are tightened by the fastening member inserted through the hole of the split seal piece, using a water leakage prevention tool in which the split seal piece has a hole through which the fastening member can be inserted. By arranging the split seal pieces between and in a tightened state, water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box can be prevented from occurring between the upper surface of the packing box and the packing retainer. It is a method of preventing between the lower surface of the

According to this, since the split seal piece can be fixed or removed between the packing box and the packing retainer for each fastening member that fastens the packing box and the packing retainer, the pressing force on the gland packing by the packing retainer is released. The seal member can be partially replaced without having to Therefore, the water leakage can be prevented without shutting down the pipeline.

A method for installing a water leakage prevention device according to the present invention comprises: a valve stem; a gland packing arranged around the valve stem and sealing an outer peripheral surface of the valve stem; a packing box containing the gland packing; and a plurality of fastening members that fasten the packing box and the packing presser. A construction method for constructing a water leakage prevention device for preventing water leakage, wherein the water leakage prevention device includes a sealing member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference, and the sealing member The split seal pieces are configured to be divisible by the same number of split seal pieces as the fastening members, and the split seal pieces have holes through which the fastening members can be inserted, and one of the plurality of fastening members is used as the fastening member. A first step of removing from the packing box and the packing retainer, and a second step of placing the split seal piece between the upper surface of the packing box from which the fastening member has been removed in the first step and the lower surface of the packing retainer. a third step of inserting the fastening member into the hole of the split seal piece arranged in the second step; and tightening the packing box and the packing presser with the fastening member inserted in the third step. and a fourth step of pressing the split seal pieces by the packing retainer, wherein all the split seal pieces of the same number as the fastening members are arranged between the upper surface of the packing box and the lower surface of the packing retainer. A series of steps from the first step to the fourth step are repeated until the desired value is obtained.

According to this, since the split seal piece can be fixed between the packing box and the packing retainer for each fastening member that fastens the packing box and the packing retainer, the pressure of the packing retainer on the gland packing is not released. A water leakage prevention device can be provided between the upper surface of the packing box and the lower surface of the packing retainer. Therefore, water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box can be prevented without shutting off the water in the pipeline.

The valve of the present invention is to which the above water leakage prevention tool is attached.

According to this, water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box can be prevented without shutting off the water in the pipeline.

In the valve of the present invention, a moving portion water leakage prevention tool is attached to prevent water leakage from between the outer peripheral surface of the valve stem and the inner peripheral surface of the gland packing, which is arranged around the valve stem above the packing retainer. Good.

According to this, it is possible to prevent water leakage from between the outer peripheral surface of the valve stem and the inner peripheral surface of the gland packing (shaft sealing movement portion of the valve) without shutting off the water supply in the pipeline.

According to the leakage prevention device, the leakage prevention method, the method for installing the leakage prevention device, and the valve of the present invention, the sealing member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference is arranged to By arranging between the gland packing and the lower surface, water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box is prevented between the upper surface of the packing box and the lower surface of the packing retainer. It is possible to prevent water leakage from the shaft seal fixing portion of the valve without replacing the packing. Therefore, it is not necessary to cut off the water supply to the pipeline while the valve is being repaired due to water leakage from the shaft seal fixing portion of the valve.

FIG. 2 is a cross-sectional view showing a main part of a valve provided with a water leakage prevention tool of the present invention; (a) is a plan view of the water leakage prevention device of the present invention, (b) is a cross-sectional view along AA of (a), and (c) is a cross-sectional view along BB of (a). , (d) is a perspective view of a split seal piece constituting the seal member of the water leakage prevention tool of the present invention. (a) is a plan view of the exercise-portion leak prevention tool, and (b) is a bottom view of the exercise-portion leak prevention tool. FIG. 2 is a cross-sectional view showing a method of installing a water leakage prevention device to a valve of the present invention, (a) is a cross-sectional view near the upper part of the valve stem before installing the water leakage prevention device, and (b) is a fixed part water leakage prevention It is a cross-sectional view near the top of the valve stem of the valve with the stud bolt removed from the packing box and the packing retainer for mounting the tool, and (c) is a cross-sectional view near the top of the valve stem of the valve with the fixed part water leakage prevention tool installed. , and (d) is a cross-sectional view of the vicinity of the upper part of the valve stem of the valve to which the fixed part water leakage prevention tool and the moving part water leakage prevention tool are attached. FIG. 4 is a cross-sectional view showing a main part of another embodiment of the valve provided with the water leakage prevention tool of the present invention; (a) is a plan view of a water leakage prevention device of another embodiment of the present invention, (b) is a CC cross-sectional view of (a), and (c) is a DD cross section of (a) It is a diagram. FIG. 4 is a cross-sectional view showing a main part of a valve provided with a water leakage prevention tool according to another embodiment of the present invention; (a) is a plan view of a water leakage prevention tool of another embodiment of the present invention, (b) is a cross-sectional view of (a) EE, and (c) is a cross-sectional view of (a) FF. It is a diagram. FIG. 4 is a cross-sectional view showing a main part of a valve provided with a water leakage prevention tool according to another embodiment of the present invention;

Hereinafter, the water leakage preventive device of the present invention and the valve provided with the water leakage preventive device of the present invention will be described.

First, a valve provided with a water leakage prevention tool of the present invention will be described. The geared sluice valve 10, which is a valve equipped with a water leakage prevention device of the present invention, is a large-diameter sluice valve that is provided in, for example, a water supply pipeline (not shown) and used for a large-diameter pipe. As shown in FIG. 1, the gate valve 10 with a gear is an inner screw type gate valve, and is arranged in a valve body 11 and a flow path (not shown) of the valve body 11 so that the flow path can be opened and closed. a disk-shaped valve body 12, a packing box 13 provided on the upper portion of the valve body 11, and a valve stem 14 rotatably supported by the packing box 13 and extending upward to open and close the valve body 12; , and an auxiliary valve stem 15 provided auxiliary to the valve stem 14 .

A gear 16 is provided at the upper end of the valve stem 14 . A through hole 16a through which a stud bolt 24 and a first hexagonal nut 25, which will be described later, can pass is formed in a predetermined portion of the gear 16. As shown in FIG. The gear 16 is formed with through holes 16a equal to or more than the number of fastening members (three sets of stud bolts 24 and first hexagonal nuts 25) attached to the packing box 13 and a packing retainer 23, which will be described later. By forming the through hole 16a in the gear 16, the stud bolt 24 and the first hexagonal nut 25 can be attached to the packing box 13 and the packing retainer 23 through the through hole 16a.

A pinion 17 is provided on the lower end side of the auxiliary valve stem 15 . The pinion 17 is arranged at a position where it can mesh with the gear 16 . The upper end of the auxiliary valve stem 15 is provided with a cap 18 for connecting an operating means (for example, a rotary handle) for movably operating the valve stem 14 from the outside. An opening meter 19 is provided at the upper end of the auxiliary valve stem 15 and at the lower end of the cap 18 .

In the geared gate valve 10, the operation means is connected to the cap 18, and the pinion 17 is rotated by operating the operation means to rotate the auxiliary valve stem 15. As shown in FIG. Further, as the pinion 17 rotates, the gear 16 meshing with the pinion 17 rotates and the valve stem 14 rotates. That is, in the geared gate valve 10, the gear 16 and the pinion 17 are used to reduce the speed and increase the torque.

The geared gate valve 10 is provided with a gland packing 20 around the axis (outer peripheral surface) of the valve stem 14 where the valve stem 14 is supported by the packing box 13 . The gland packing 20 prevents water leakage from the portion where the valve stem 14 is supported by the packing box 13 . The gland packing 20 is configured by a ring-shaped member having a predetermined width so as to cover the outer peripheral surface of the valve stem 14 .

The packing box 13 has a holding portion 13a having a generally concave cross-sectional shape for holding the gland packing 20, and a first flange portion 13b extending outward from the upper portion of the holding portion 13a. A threaded hole 13c into which a stud bolt 24 is screwed is formed in the first flange portion 13b. A cover 21 is attached to the top of the packing box 13 . A cover 21 is attached to the packing box 13 so as to cover the upper portion of the valve stem 14, the gear 16, the pinion 17, and the like. The cover 21 holds the auxiliary valve stem 15 via bearings 22,22.

The geared gate valve 10 is provided with a packing retainer 23 that presses and holds the gland packing 20 against the packing box 13 . The packing retainer 23 includes a cylindrical portion 23a that presses the upper end surface of the gland packing 20, and a disk-shaped second flange portion 23b that extends laterally from one end of the cylindrical portion 23a. A first hole portion 23c through which the stud bolt 24 is inserted is formed in the second flange portion 23b. The packing retainer 23 is fixed to the upper portion of the packing box 13 by a fastening member consisting of a stud bolt 24 and a first hexagonal nut 25 . The packing retainer 23 is fixed to the packing box 13 by three fastening members (three sets of stud bolts 24 and first hexagonal nuts 25). The pressure of the packing retainer 23 against the gland packing 20 is adjusted by tightening the first hexagonal nut 25 against the stud bolt 24 and moving the first hexagonal nut 25 in the axial direction of the valve stem 14 .

In the geared gate valve 10, when water leaks from the shaft seal fixing portion K (between the outer peripheral surface of the gland packing 20 and the inner peripheral surface of the packing box 13) of the geared gate valve 10 due to aged deterioration of the gland packing 20. In such a case, by tightening the first hexagonal nut 25 against the stud bolt 24 and adjusting the pressure of the packing retainer 23 against the gland packing 20, the shaft seal fixing portion K Prevents water leakage from However, even if the pressure of the packing retainer 23 against the gland packing 20 is adjusted, there are cases where water leakage from the shaft seal fixing portion K of the geared gate valve 10 cannot be prevented. Therefore, in the geared gate valve 10, water leakage from the shaft seal fixing portion K of the geared gate valve 10 is prevented by using a fixed portion water leakage prevention device 30 (an example of a “water leakage prevention device”).

As shown in FIG. 1 , the fixed portion water leakage prevention tool 30 is arranged between the packing box 13 and the packing retainer 23 . The fixed portion water leakage prevention tool 30 is formed in a ring shape so as to contact the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23 over the entire circumference.

An arc-shaped rounded portion R is formed over the entire circumference at the corner portion between the outer peripheral surface of the cylindrical portion 23a of the packing retainer 23 and the lower surface 23d of the second flange portion 23b. The size of this rounded portion R may vary depending on the manufacturer of the geared gate valve 10 . Therefore, in the geared gate valve 10, in order to arrange the fixed part water leakage prevention tool 30 between the packing box 13 and the packing retainer 23 for the geared gate valve 10 of a different manufacturer, the fixed part water leakage prevention tool 30 By setting the inner diameter to be larger than the outer diameter of the rounded portion R of the packing retainer 23, a gap S is formed between the fixed portion water leakage prevention tool 30 and the cylindrical portion 23a of the packing retainer 23. .

As shown in FIG. 2, the fixed portion water leakage prevention device 30 includes a seal member 31 configured by three split seal pieces 31A, and a connecting member (bolt 32 and nut 33) for connecting the split seal pieces 31A. , consists of

The sealing member 31 is a member that contacts the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23 over the entire circumference. The seal member 31 is configured to be divisible by three split seal pieces 31A, and is formed into a ring shape by connecting the three split seal pieces 31A with bolts 32 and nuts 33. As shown in FIG. When the sealing member 31 is arranged between the packing box 13 and the packing retainer 23 , the lower surface of the sealing member 31 abuts the upper surface of the first flange portion 13 b of the packing box 13 over the entire circumference, and the upper surface of the sealing member 31 contacts the first flange portion 13 b of the packing box 13 . 2 It abuts on the lower surface of the flange portion 23b over the entire circumference.

The split seal piece 31A that constitutes the seal member 31 is an arc-shaped member that is formed by dividing the ring-shaped seal member 31 into three equal parts. Here, the number of split seal pieces 31A constituting the seal member 31 is set to the same number as the number of fastening members (stud bolts 24 and first hexagonal nuts 25) that fasten the packing box 13 and the packing retainer 23 together. That is, in the geared gate valve 10, the packing box 13 and the packing retainer 23 are fastened by three fastening members (three sets of stud bolts 24 and first hexagonal nuts 25). It is composed of a split seal piece 31A. 31 A of division|segmentation seal pieces are comprised by the arc-shaped core metal 31a and the rubber material 31b (an example of an "elastic material") with which the core metal 31a is lined.

A second hole 31c (an example of a “hole”) is formed in the central portion of the cored bar 31a. The stud bolt 24 is inserted through the second hole portion 31c. The second hole portion 31c overlaps the screw hole 13c of the packing box 13 and the first hole portion 23c of the packing retainer 23 in plan view when the sealing member 31 is arranged between the packing box 13 and the packing retainer 23. formed in Third flange portions 31d are formed at both ends of the cored bar 31a so as to protrude outward from both ends of the cored bar 31a. A third hole portion 31e is formed in the third flange portion 31d. A bolt 32 for connecting the adjacent split seal pieces 31A is inserted through the third hole 31e.

As shown in FIG. 2(b), the rubber material 31b is a plate-shaped member, and includes the upper surface, the inner peripheral side surface, the lower surface, and both end surfaces (surfaces where the adjacent split seal pieces 31A are in contact with each other) of the core metal 31a. The core bar 31a is lined in a substantially U-shaped vertical cross-section so as to cover the core metal 31a. By lining the core metal 31a with the rubber material 31b in this manner, the bonding strength of the rubber material 31b to the upper and lower surfaces of the core metal 31a can be increased. In addition, by lining the core metal 31a with a plate-like (surface-like) rubber material 31b to form a split seal piece 31A (seal member 31), the upper surface 13d of the packing box 13 and the second flange portion of the packing retainer 23 are formed. There is no need to demand strict dimensional tolerances for the surface roughness of the lower surface 23d of 23b.

As shown in FIG. 1, in the geared sluice valve 10, due to aged deterioration of the gland packing 20, etc., there is In such a case, by tightening the first hexagonal nut 25 against the stud bolt 24 and adjusting the pressure of the packing retainer 23 against the gland packing 20, the gate valve with gear Water leakage from the shaft seal movement portion U of 10 is prevented. However, even if the pressure of the packing retainer 23 against the gland packing 20 is adjusted, it may not be possible to prevent water leakage from the shaft sealing movement portion U of the geared gate valve 10 . Therefore, in the geared gate valve 10 , water leakage from the shaft sealing movement portion U of the geared gate valve 10 is prevented by using the moving portion water leakage prevention tool 40 .

The moving part water leakage prevention tool 40 is arranged on the upper surface of the packing retainer 23 . The moving portion water leakage prevention device 40 is composed of an O-ring 41 , an O-ring case 42 for holding the O-ring 41 , and a pressing plate 43 for pressing the O-ring case 42 .

The O-ring 41 is a string-like member that can be wound around the outer peripheral surface of the valve stem 14 . The O-ring 41 is wound around the outer peripheral surface of the valve stem 14 and then adhered to form an annular shape.

As shown in FIGS. 1 and 3B, the O-ring case 42 is configured to be divisible by two split concave pieces 42a, and by connecting the two split concave pieces 42a with a reamer bolt 42b and a nut 42c, The concave portions 42d of the split concave pieces 42a are connected to form a rectangular member having an annular triangular groove 42e capable of holding the O-ring 41. As shown in FIG. The O-ring case 42 is arranged to cover the O-ring 41 wound around the outer peripheral surface of the valve stem 14 from above, and holds the O-ring 41 in an annular triangular groove 42e.

As shown in FIGS. 1 and 3(a), the pressing plate 43 is configured to be divisible by two semi-circular pieces 43a, and the two semi-circular pieces 43a are connected by an O-ring case 42. and formed into a ring shape. The retainer plate 43 is formed with an elongated hole 43b through which the stud bolt 24 can be inserted. In the retainer plate 43 , a hole 43 c formed by connecting two split semicircular pieces 43 a is fitted to the valve stem 14 , and the lower surface of the peripheral edge of the hole 43 c is in contact with the O-ring case 42 . The O-ring case 42 is pressed from above. Pressing plate 43 against O-ring case 42 is adjusted by tightening second hexagonal nut 35 to stud bolt 24 and moving second hexagonal nut 35 in the axial direction of valve stem 14 .

Next, a method for installing the fixed portion water leakage prevention device 30 and the moving portion water leakage prevention device 40 to the geared gate valve 10 will be described. In the geared sluice valve 10, the water leakage prevention devices are constructed in the order of the fixed portion water leakage prevention device 30 and the moving portion water leakage prevention device 40. As shown in FIG.

FIG. 4(a) is a view of the shaft seal portion of the geared gate valve 10 without the fixed portion water leakage prevention device 30 and the moving portion water leakage prevention device 40 attached. When installing the fixed part water leakage prevention tool 30 and the moving part water leakage prevention tool 40, first, as shown in FIG. One set of stud bolts 24 and the first hexagonal nut 25 of the nuts 25 are removed from the packing box 13 and the packing retainer 23 ("first step"). At this time, the stud bolt 24 and the first hexagonal nut 25 are removed from the through hole 16 a of the gear 16 . Here, since the packing box 13 and the packing retainer 23 are fastened by the remaining two sets of stud bolts 24 and the first hexagonal nut 25, the gland packing 20 is held in a state of being pressed by the packing retainer 23, and the gland Excessive water leakage does not occur other than water leakage due to aged deterioration of the packing 20 or the like. Subsequently, the top surface 13d of the packing box 13 and the bottom surface 23d of the second flange portion 23b of the packing retainer 23, which are the mounting surfaces (abutment surfaces) of the seal member 31 of the fixed portion water leakage preventive device 30, are removed.

Next, as shown in FIG. 4(c), after cleaning the upper surface 13d of the packing box 13 from which the stud bolt 24 has been removed and the lower surface 23d of the second flange portion 23b of the packing retainer 23, the sealing member 31 One of the three split seal pieces 31A constituting the is installed (“second step”). At this time, the split seal piece 31A is arranged so that the screw hole 13c of the packing box 13 and the first hole portion 23c of the packing retainer 23 and the second hole portion 31c of the split seal piece 31A overlap in plan view. After installing the split seal piece 31A, a new stud bolt 24 is inserted through the screw hole 13c of the packing box 13, the first hole portion 23c of the packing retainer 23, and the second hole portion 31c of the split seal piece 31A ("third step ”). At this time, the stud bolt 24 is inserted through the through hole 16 a of the gear 16 . Then, the stud bolt 24 is screwed into the screw hole 13c and attached to the first flange portion 13b of the packing box 13, and the packing box 13 and the packing retainer 23 are tightened by the stud bolt 24 and the first hexagonal nut 25 that are inserted. Then, the split seal piece 31A is pressed by the packing retainer 23 ("fourth step"). Here, the packing box 13 and the packing retainer 23 are tightened by the stud bolt 24 and the first hexagonal nut 25 to the extent that water does not leak excessively from the shaft seal fixing portion K of the gate valve 10 with gear.

Further, from the first step until the remaining two split seal pieces 31A constituting the seal member 31 are arranged between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23, A series of steps up to the fourth step are repeated. By arranging the three split seal pieces 31A between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23, the adjacent split seal pieces 31A are separated from each other by the bolt 32 and the nut. 33. Furthermore, by sequentially tightening the packing box 13 and the packing retainer 23 with the three stud bolts 24 and the first hexagonal nut 25, water leakage from the shaft seal fixing portion K of the geared gate valve 10 due to aged deterioration of the gland packing 20 can be prevented. The three split seal pieces 31A are pressed in order by the packing retainer 23 to such an extent that a crack does not occur. As a result, the fixed portion water leakage prevention device 30 is arranged between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23, and the rubber material 31b vulcanized and bonded to the core metal 31a is compressed. As a result, water leakage from the shaft seal fixing portion K of the geared gate valve 10 is prevented between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23. prevented.

Subsequently, as shown in FIG. 4(d), in order to arrange the moving part water leakage prevention tool 40 on the upper surface of the packing retainer 23, the O-ring 41 is wound around the outer peripheral surface of the valve stem 14 and adhered in an annular shape. Furthermore, grease is applied to the inner and outer surfaces of the O-ring 41 to reduce the frictional force between the valve stem 14 and the O-ring 41 when the valve stem 14 rotates. By covering the O-ring 41 with the O-ring case 42 from above, the O-ring 41 is housed in the triangular groove 42 e of the O-ring case 42 .

Subsequently, the retainer plate 43 is arranged on the O-ring case 42 . At this time, the stud bolt 24 protruding from the packing retainer 23 is inserted through the long hole 43 b of the retainer plate 43 . Further, a second hexagonal nut 35 is attached to each of the three stud bolts 24 , and the attached second hexagonal nut 35 is tightened to press the O-ring case 42 with the pressing plate 43 . As a result, the O-ring 41 is compressed by the O-ring case 42, and exhibits waterproofing against water leakage from the shaft seal movement portion U of the geared gate valve 10, and also functions to open and close the geared gate valve 10. Guarantee. By providing the geared sluice valve 10 with the moving portion water leakage prevention device 40, the portion where the valve stem 14 and the O-ring case 42 contact in the vertical direction (the portion in the vertical direction of the O-ring case 42) and the packing retainer 23 and the O-ring case 42 in the horizontal direction (the horizontal portion of the O-ring case 42). By compressing the O-ring 41, the O-ring case 42 is able to exhibit waterproof performance against water leakage from the vertical portion of the O-ring case 42 and the horizontal portion of the O-ring case 42. As shown in FIG.

As described above, according to the present embodiment, the seal member 31 that abuts on the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23 over the entire circumference is positioned between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23. By arranging between the lower surface 23d of the second flange portion 23b of the packing retainer 23 and the upper surface 13d of the packing box 13, water leakage from between the outer peripheral surface of the gland packing 20 and the inner peripheral surface of the packing box 13 is prevented. Since leakage is prevented between the packing retainer 23 and the lower surface 23d of the second flange portion 23b, water leakage from the shaft seal fixing portion K of the geared gate valve 10 can be prevented without replacing the gland packing 20. Therefore, it is not necessary to cut off water supply to the pipeline while the geared gate valve 10 is being repaired due to water leakage from the shaft seal fixing portion K of the geared gate valve 10 .

Furthermore, according to the present embodiment, the fixed portion water leakage prevention tool 30 (seal member 31) is divided into the same number as the fastening members (stud bolts 24 and first hexagonal nuts 25) that fasten the packing box 13 and the packing retainer 23. The split seal piece 31A is fixed between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23 by the stud bolt 24 inserted through the second hole portion 31c. Therefore, the split seal piece 31A is fixed between the packing box 13 and the packing presser 23 for each fastening member (stud bolt 24 and first hexagonal nut 25) that fastens the packing box 13 and the packing presser 23, or can be removed. Therefore, the seal member 31 can be partially replaced without releasing the pressure of the gland packing 20 by the packing retainer 23 .

In the present embodiment, the gate valve with gear 10 is used as the valve for constructing the fixed portion water leakage prevention device 30 and the moving portion water leakage prevention device 40, but it is not limited to this. The stationary portion water leakage prevention device 30 and the moving portion water leakage prevention device 40 may be constructed on the sluice valve 10A as shown. As shown in FIG. 5, the gate valve 10A does not have the auxiliary valve stem 15, the gear 16, and the pinion 17 like the geared gate valve 10, and opens and closes the valve body 12 only with the valve stem 14. As shown in FIG. Therefore, a cap 18 is provided on the upper portion of the valve stem 14 . In the gate valve 10A, similarly to the geared gate valve 10, the fixed portion water leakage prevention tool 30 is arranged between the upper surface 13d of the packing box 13 and the lower surface 23d of the second flange portion 23b of the packing retainer 23, thereby Leakage from the shaft seal fixing portion K (between the outer peripheral surface of the gland packing 20 and the inner peripheral surface of the packing box 13) of the valve 10A prevent between Furthermore, in the gate valve 10A, as in the geared gate valve 10, by arranging the moving part water leakage prevention device 40 on the upper part of the packing retainer 23, the shaft sealing moving part U (the outer peripheral surface of the valve stem 14) of the gate valve 10A and the inner peripheral surface of the gland packing 20) is prevented by the upper portion of the packing retainer 23.

Further, in the present embodiment, the seal member 31 of the fixed portion water leakage prevention tool 30 is composed of three split seal pieces 31A, but is not limited to this. (That is, in the case of two sets of stud bolts 24 and first hexagonal nuts 25), the seal member 31 may be composed of two split seal pieces 31A, like the fixed part water leakage prevention tool 30A shown in FIG. . Alternatively, when the number of fastening members is four sets (that is, four sets of stud bolts 24 and first hexagonal nuts 25), the sealing member is formed by four split seal pieces 31A, as in the fixed part water leakage prevention tool 30B shown in FIG. 31 may be configured.

As shown in FIG. 7, the gate valve 10B on which the fixed part water leakage prevention device 30A is arranged has a stand 50 for supporting the valve stem 14 above the packing box 13. As shown in FIG. A leg portion 51 of the stand 50 is formed with an opening 52 for attaching the stud bolt 24, the first hexagonal nut 25, the fixed portion water leakage prevention device 30A, and the moving portion water leakage prevention device 40 to the packing box 13 and the packing retainer 23. ing. The sluice valve on which the fixed portion water leakage prevention device 30A is arranged is not limited to the sluice valve 10B having the stand 50, and the sluice valve without the stand 50 may be arranged.

As shown in FIG. 9, the geared gate valve 10C on which the fixed portion water leakage prevention device 30B is arranged has a gear 16 for rotating the valve stem 14. As shown in FIG. The gear 16 is formed with through holes 16a equal to or more than the number of fastening members (four sets of stud bolts 24 and first hexagon nuts 25) attached to the packing box 13 and the packing retainer 23. As shown in FIG. The gate valve on which the fixed portion water leakage prevention device 30B is arranged is not limited to the gate valve with gear 10C having the gear 16, and may be arranged on a gate valve without the gear 16.

In the present embodiment, an inner screw type gate valve (the geared gate valve 10) is used, but the present invention is not limited to this, and an outer screw type gate valve may be used. Further, the fixed portion water leakage prevention tool 30 may be applied to the shaft seal portion of a valve other than the gate valve.

In the present embodiment, the sealing member 31 has the core metal 31a and the rubber material 31b, but it is not limited to this. can be configured. In this case, the rubber member 31b corresponding to the metal core 31a may be made of hard rubber and the periphery thereof may be lined with soft rubber.

10 gate valve with gear (valve)
13 Packing box 14 Valve stem 20 Gland packing 23 Packing retainer 23c First hole (hole)
24 stud bolt (fastening member)
25 first hexagonal nut (fastening member)
30 Fixed part water leakage prevention tool (water leakage prevention tool)
31 seal member 31A split seal piece 40 motion part water leakage prevention device (water leakage prevention device)

Claims (8)

A valve stem, a gland packing that is arranged around the valve stem and seals the outer peripheral surface of the valve stem, a packing box that houses the gland packing, and a packing presser that presses the gland packing from above. at the valve,
By arranging a sealing member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference between the upper surface of the packing box and the lower surface of the packing retainer, the outer peripheral surface of the gland packing and the A water leakage prevention tool, characterized by preventing water leakage between the inner peripheral surface of the packing box and the upper surface of the packing box and the lower surface of the packing retainer. In the valve comprising a plurality of fastening members for fastening the packing box and the packing retainer,
The seal member is configured to be divisible by the same number of split seal pieces as the fastening member,
The split seal pieces are
having a hole through which the fastening member can be inserted;
The water leakage prevention tool according to claim 1, wherein the fastening member inserted through the hole is fixed between the upper surface of the packing box and the lower surface of the packing retainer. The split seal piece is tightened between the upper surface of the packing box and the lower surface of the packing presser by tightening the packing box and the packing presser with the fastening member inserted through the hole. The water leakage prevention tool according to claim 2. The sealing member has a core metal and an elastic material lined on the core metal,
The water leakage prevention tool according to any one of claims 1 to 3, wherein the elastic member abuts on the upper surface of the packing box and the lower surface of the packing retainer. A valve stem, a gland packing arranged around the valve stem and sealing the outer peripheral surface of the valve stem, a packing box containing the gland packing, and a packing retainer for pressing the gland packing from above. A water leakage prevention method for preventing water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box in a valve in which the packing box and the packing retainer are fastened by a plurality of fastening members, ,
A sealing member is provided that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference, and the sealing member is configured to be divisible by the same number of divided seal pieces as the fastening member, and the divided seal pieces are connected to the fastening member. Using a water leakage prevention tool having a hole through which the member can be inserted,
By arranging the split seal piece between the packing box and the packing retainer tightened by the fastening member inserted through the hole of the split seal piece, the outer circumference of the gland packing is tightened. A water leakage prevention method, comprising: preventing water leakage from between a surface and an inner peripheral surface of the packing box between an upper surface of the packing box and a lower surface of the packing retainer. A valve stem, a gland packing arranged around the valve stem and sealing the outer peripheral surface of the valve stem, a packing box containing the gland packing, a packing retainer for pressing the gland packing from above, and the packing A valve equipped with a plurality of fastening members that fasten a box and the packing retainer is constructed by installing a water leakage prevention tool for preventing water leakage from between the outer peripheral surface of the gland packing and the inner peripheral surface of the packing box. a method,
The water leakage prevention tool is
a sealing member that abuts on the upper surface of the packing box and the lower surface of the packing retainer over the entire circumference,
The seal member is configured to be divisible by the same number of split seal pieces as the fastening member,
The split seal piece has a hole through which the fastening member can be inserted,
a first step of removing one of the plurality of fastening members from the packing box and the packing gland;
a second step of arranging the split seal piece between the upper surface of the packing box from which the fastening member has been removed in the first step and the lower surface of the packing retainer;
a third step of inserting the fastening member into the hole of the split seal piece arranged in the second step;
a fourth step of pressing the split seal piece with the packing presser by tightening the packing box and the packing presser with the fastening member inserted in the third step;
with
Repeating the series of steps from the first step to the fourth step until all the split seal pieces equal in number to the fastening members are arranged between the top surface of the packing box and the bottom surface of the packing retainer. A construction method for a water leakage prevention tool characterized by: A valve to which the water leakage prevention tool according to any one of claims 1 to 4 is attached. A moving portion water leakage prevention tool is provided around the valve stem above the packing retainer to prevent water leakage from between the outer peripheral surface of the valve stem and the inner peripheral surface of the gland packing. 8. A valve according to claim 7.

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