JPH0583396U - Sealing structure of shaft seal part in pump - Google Patents

Abstract

(57) [Summary] [Purpose] The durability of the oil seal is improved, and the maintenance cost of the pump can be reduced and the transportation efficiency can be improved.
To provide a seal structure for a shaft seal portion in a pump. [Structure] A rotary shaft rotatably supported by a bearing is passed through an opening hole of the housing, a blade is connected to an end of the rotary shaft located in the housing, and the rotary shaft is provided between the rear surface of the housing and the bearing. In a pump in which a plurality of oil seals are provided to form a shaft seal portion and a blade is rotated to suck and discharge a slurry-like material into the housing, an annular packing is attached around the opening hole, and It is characterized in that the peripheral surface is pressed against the peripheral surface of the rotary shaft to close the gap between the opening hole of the housing and the peripheral surface of the rotary shaft.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a seal structure of a shaft sealing portion in a pump that pumps at high pressure such as a slurry pump.

[0002]

[Prior Art]

 Pumps used for the transportation of slurries such as soil and ore require higher pumping power as the transportation distance increases. In this type of slurry pump, since it is necessary to protect the bearing that supports the rotating shaft, the sealing performance of the shaft sealing portion where the rotating shaft penetrates the pump housing is important. As a sealing means of the shaft sealing portion, a method of using a special oil seal that is a combination of a special oil (grease or the like) and an oil seal is known. This special oil seal is composed of an oil seal that forms an annular sealed space with the peripheral surface of the rotating shaft, and an injection device seal that pressurizes grease into the oil seal. An oil film is formed between the oil seal and the peripheral surface of the rotating shaft to ensure high water resistance.

[0003]

[Problems to be solved by the present invention]

 The above-described conventional bearing sealing technology has the following problems. <a> Since the transport pressure is high, it is technically difficult to completely seal between the pump housing and the rotary shaft, and some leakage of slurry is allowed. As a result, the leaked slurry-like material enters between the oil seal and the peripheral surface of the rotating shaft, causing problems such as grease leakage and damage to the rotating shaft due to wear of the oil seal. It has also been pointed out that the higher the discharge pressure of the pump, the shorter the replacement period of the special oil seal. <B> Special oil seals are extremely expensive (about several hundred thousand yen to one million). The maintenance cost of the pump is extremely high because the expensive special oil seal must be replaced frequently. <C> Pump operation must be frequently interrupted to replace the special oil seal, and the efficiency of transporting slurry-like substances is low.

[0004]

[Purpose of the present invention]

 The present invention has been made in view of the above points, and its purpose is to improve the durability of the oil seal, reduce the maintenance cost of the pump, and improve the transportation efficiency. It is to provide a seal structure for a shaft seal portion.

[0005]

[Means for solving problems]

 That is, according to the present invention, the rotary shaft supported by the bearing is passed through the opening hole of the housing, the blade is connected to the end of the rotary shaft located in the housing, and the rotary shaft is provided between the rear surface of the housing and the bearing. In this pump, a plurality of oil seals are provided to form a shaft-sealing portion, and the blades are rotated to suck and discharge the slurry-like material into the housing, and an annular packing is attached around the opening hole. A seal structure of a shaft seal portion in a pump, characterized in that an inner peripheral surface of the packing is brought into pressure contact with a peripheral surface of the rotary shaft to close a gap between an opening hole of the housing and the peripheral surface of the rotary shaft.

[0006]

First Embodiment The present invention will be described below with reference to the drawings. <B> Overall Description of Pump FIG. 1 shows an example of a slurry pump. The slurry pump has blades 20 housed in a housing 10, and the blades 20 are connected to one end of a rotary shaft 30 that penetrates the housing 10. The blade 20 has fins of different diameters on its front and rear surfaces. A suction port 11 is formed in a part of the housing 10 in the same direction as the rotary shaft 30, and a discharge port 12 is formed in a direction orthogonal to the rotary shaft 30. The middle and end of the rotary shaft 30 are rotatably supported by bearings 40 and 41. A slinger 31 having an L-shaped cross section, a replaceable sleeve 32, and an umbrella-shaped draining ring 33 are fixed to the peripheral surface of the rotary shaft 30 in this order from the blade 20 side, and these members rotate together with the rotary shaft 20. To do.

<B> Shaft Sealing Part FIG. 2 shows an enlarged view of the shaft sealing part. The shaft sealing portion includes a stuffing box 50, an annular packing 60 interposed between the stuffing box 50 and the rear surface of the housing 10, a seal box 52, and a plurality of oil seals 53 accommodated in the seal box 52. , The seal cover 54 are the basic components.

<C> Combination of other sealing means Stop rings 55 and 56 are provided in stages between the slinger 31 and the seal box 52 facing each other, and both rings 55 are passed through a water injection path 57 of the seal box 52. , 56 form a seal structure by sending pressurized water into the space defined between the 56 and 56. Incidentally, the sealing means by the stop rings 55 and 56 may be omitted.

<D> Annular packing In the present invention, a mechanical seal is provided by an annular packing 60, which is arranged for the purpose of sealing the opening 13 of the housing 10 through which the rotary shaft 30 penetrates, and an oil passage 58 is introduced into the oil seal 53. The feature is that it is used together with a special oil seal that injects special oil under pressure. The ring-shaped packing 60 is formed into a disc shape with rubber or resin having excellent wear resistance, and its inner diameter is set smaller than the inner diameter of the opening hole 13 of the housing 10 so as to be crimped to the outer diameter of the slinger 31. . The annular packing 60 is fixed by sandwiching its outer peripheral portion between the back surface of the housing 10 and the side surface of the stuffing box 50, or by adhering it to the back surface of the housing 10. It is important that the annular packing 60 be set by inclining the lip 61 thereof toward the blade 20.

<E> Oil Seal The oil seal 53 is a known seal member having a hook-shaped cross section, and an annular sealed space is formed between the seals 53. A lantern ring 51 having a plurality of openings on the peripheral surface is interposed in the center of the row of oil seals 53, and the lantern ring 51 has a function of supplying the special oil injected from the oil passage 58 into each oil seal 53. Is a member having.

[0011]

[Action]

 Next, the sealing action during operation of the pump will be described. <A> In operation In FIG. 1, when the rotary shaft 30 is rotated in a specific direction, the blade 20 at the end of the rotary shaft 30 starts to rotate. At the same time, pressure feeding of high-pressure water or special oil to the water injection passage 57 and the oil injection passage 58 is started. Negative pressure is generated in the housing 10 by the rotation of the blades 20, and the slurry-like material such as soil and ore sucked from the suction hole 11 side is transferred to the discharge port 12. Due to the operation of the pump, the internal pressure of the housing 10 accommodating the blades 20 increases, and a part of the slurry-like material tries to leak from the space between the opening hole 13 of the housing 10 and the slinger 31 shown in FIG. Up to now, it is a matter of course that a gap is provided between the opening hole 13 and the slinger 31 in order to rotate the rotary shaft 30, and the slurry-like substance leaked from this gap may be blocked by the stop rings 55 and 56. Was the idea. The present invention does not deal with the problem by adding a seal portion in a short period of time, but suppresses leakage at the initial stage and copes with the problem. That is, as shown in the enlarged view of FIG. The whole 61 is bent and the restoring force F1 is accumulated inside. Further, a part of the pressure of the slurry-like material acting on the inclined surface of the lip portion 61 located in the opening hole 13 acts as the pressure force F2 of the slinger 31 in the circumferential surface direction. As a result, the pressure force between the lip portion 61 and the slinger 31 is increased in place of these two forces F1 and F2, and the leakage of the slurry-like material is effectively suppressed. Should the slurry-like material leak due to wear of the annular packing 60, the stop rings 55 and 56 seal. As a result, the replacement period of the oil seal 53 becomes longer than in the conventional case.

<B> Replacement of Annular Packing Wear of the annular packing 60 is unavoidable. Therefore, when the annular packing 60 reaches the limit of the rule function, it is replaced with a new annular packing 60 when the pump is stopped (set as a constant operation time of the slurry pump).

[0013]

Second Embodiment FIG. 4 shows another annular packing 60a. In the present embodiment, the rigidity of the reinforcing plate 62 can be increased by attaching the reinforcing plates 62 such as steel plates to both surfaces of the annular packing 60 of the above embodiment.

[0014]

[Effect of the device]

 Since the present invention is as described above, the following effects can be obtained. <A> By arranging the annular packing around the opening hole of the housing through which the rotary shaft penetrates, it is possible to effectively prevent the slurry-like substance from leaking from the gap between the opening holes at the initial stage. As a result, the replacement period of the oil seal can be greatly extended.

<B> As described above, the maintenance cost can be reduced and the operating time can be extended at the same time as the replacement period of the expensive oil seal is extended.

<C> There are few additional parts, and it is easy to apply to existing pumps.

[Brief description of drawings]

FIG. 1 is an explanatory view of the entire pump in an explanatory view according to the present invention.

[Fig. 2] Enlarged view of the shaft seal part

FIG. 3 is an enlarged view of a lip portion of the annular packing.

FIG. 4 is a partial sectional view of an annular packing according to a second embodiment.

Claims (1)

[Scope of utility model registration request] 1. A rotary shaft rotatably supported by a bearing is passed through an opening hole of the housing, and a blade is connected to an end of the rotary shaft located in the housing, and the rotary shaft is provided between the rear surface of the housing and the bearing. In a pump that is provided with a plurality of oil seals to form a shaft sealing portion and rotates a blade to suck and discharge the slurry-like material into the housing, an annular packing is attached around the opening hole. A seal structure for a shaft seal portion of a pump, characterized in that the inner peripheral surface of the shaft is pressed against the peripheral surface of the rotary shaft to close the gap between the opening hole of the housing and the peripheral surface of the rotary shaft.