CN219345240U

CN219345240U - Top cover connecting device of pumped storage unit

Info

Publication number: CN219345240U
Application number: CN202223014311.2U
Authority: CN
Inventors: 赵毅锋; 赵强; 于姗; 曹佳丽; 周攀; 唐拥军; 董阳伟; 徐亚鹏; 章亮
Original assignee: Pumped Storage Technology And Economy Research Institute Of State Grid Xinyuan Holding Co ltd; State Grid Xinyuan Co Ltd
Current assignee: Pumped Storage Technology And Economy Research Institute Of State Grid Xinyuan Holding Co ltd; State Grid Xinyuan Co Ltd
Priority date: 2022-11-11
Filing date: 2022-11-11
Publication date: 2023-07-14
Anticipated expiration: 2032-11-11

Abstract

The utility model provides a top cover connecting device of a pumped storage unit, wherein a top cover is connected with a seat ring through bolts and nuts, a buffer gasket is arranged between the nuts and the top cover, the sectional area of the buffer gasket is larger than that of the nuts, and the strength of the buffer gasket is larger than that of the top cover. When the pretightening force is applied to the bolt, the total load borne by the bolt acts on the top cover through the nut and the buffer gasket, the acting area is increased from the sectional area of the nut to the sectional area of the buffer gasket, and the stress borne by the top cover is reduced by increasing the acting area, so that the damage caused by overlarge local stress of the top cover can be avoided, and the use requirement is met.

Description

Top cover connecting device of pumped storage unit

Technical Field

The utility model relates to the technical field of pumped storage, in particular to a top cover connecting device of a pumped storage unit.

Background

When the pumped storage unit operates, the top cover bears larger water pressure dynamic load, if the top cover connecting piece is not fastened, bolt breakage can possibly occur after long-time operation, and the top cover is lifted, so that the unit is damaged, even serious accidents of a water flooding factory building occur, and huge life and property losses are caused. According to the requirements of related technical specifications, the top cover connecting piece should meet certain pretightening force requirements, however, for some old units, as the strength of the top cover is lower, if pretightening force is improved, the risk of collapse due to overlarge local load can occur.

Disclosure of Invention

Therefore, the utility model aims to provide a top cover connecting device of a pumped storage unit, which can reduce the stress on the top cover and avoid the damage of the top cover.

Based on the above purpose, the utility model provides a top cover connecting device of a pumped storage unit, wherein the top cover is connected with a seat ring through bolts and nuts, a buffer gasket is arranged between the nuts and the top cover, and the sectional area of the buffer gasket is larger than that of the nuts.

Optionally, the strength of the buffer pad is greater than the strength of the top cover.

Optionally, the top cover is provided with a plurality of first screw holes, the seat ring is provided with a plurality of second screw holes corresponding to the first screw holes, and each group of corresponding first screw holes and second screw holes are connected through the nuts, the buffer gaskets and the bolts.

Optionally, each group of corresponding first screw holes and second screw holes are connected with one buffer pad, and two buffer pads of adjacent groups are not contacted.

Optionally, the buffer gasket is an integral annular gasket which is adapted to the shape of the top cover, and connecting holes are respectively arranged on the buffer gasket at positions corresponding to the first screw holes on the top cover.

Optionally, the thickness of the cushion pad is 20 mm.

Optionally, the buffer gasket is made of Q345 steel.

From the above, the top cover connecting device of the pumped storage unit provided by the utility model is characterized in that the top cover is connected with the seat ring through the bolts and the nuts, the buffer gasket is arranged between the nuts and the top cover, the sectional area of the buffer gasket is larger than that of the nuts, and the strength of the buffer gasket is larger than that of the top cover. When the pretightening force is applied to the bolt, the total load borne by the bolt acts on the top cover through the nut and the buffer gasket, the acting area is increased from the sectional area of the nut to the sectional area of the buffer gasket, and the stress borne by the top cover is reduced by increasing the acting area, so that the damage caused by overlarge local stress of the top cover can be avoided, and the use requirement is met.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a portion of a top cover of some embodiments;

FIG. 2 is a schematic view of a connection structure between a top cover and a seat ring according to some embodiments;

FIG. 3 is a schematic view of a connecting device according to an embodiment of the present utility model;

fig. 4 is a schematic view of a bearing area of a nut and a bearing area of a cushion plate according to an embodiment of the present utility model.

Detailed Description

The present utility model will be further described in detail below with reference to specific embodiments and with reference to the accompanying drawings, in order to make the objects, technical solutions and advantages of the present utility model more apparent.

It should be noted that unless otherwise defined, technical or scientific terms used in the embodiments of the present utility model should be given the ordinary meaning as understood by one of ordinary skill in the art to which the present disclosure pertains. The terms "first," "second," and the like, as used in this disclosure, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.

As shown in fig. 1 and 2, the pumped storage unit comprises a top cover 10 and a seat ring 20, wherein the top cover 10 and the seat ring 20 are connected through nuts 40 and bolts 30, and in order to ensure the connection tightness of the top cover 10 and the seat ring 20, the pretightening force applied to the bolts 30 should meet the requirements of relevant technical specifications. When the bolt 30 is fastened, the total load applied to the bolt 30 is a tensile force, the top cover 10 is also subjected to the load of the same magnitude by the nut 40, and the acting area is the sectional area of the nut 40. For some old units, the top cover is generally made of low-carbon steel or low-alloy steel with lower strength, and the top cover has better weldability but lower strength, so that when the bolt pretightening force is improved, the top cover may have excessive local load and collapse risk.

In view of this, this application embodiment is to not high and appear the too big problem of local load easily to top cap intensity in the old unit, proposes a pumped storage unit top cap connecting device, can reduce the top cap and receive the load, avoids the top cap damage.

As shown in fig. 3, in the pumped storage unit top cover connecting device provided in the embodiment of the present application, the top cover 10 is connected with the seat ring 20 through the bolts 30 and the nuts 40, and the buffer gasket 50 is disposed between the nuts 40 and the top cover 10, and the cross-sectional area of the buffer gasket 50 is larger than that of the nuts 40. When the pretightening force is applied to the bolt 30, the total load borne by the bolt 30 acts on the top cover 10 through the nut 40 and the buffer gasket 50, the acting area is increased from the sectional area of the nut 40 to the sectional area of the buffer gasket 50, and under the condition that the total load is unchanged, the stress borne by the top cover is reduced by increasing the acting area, so that the top cover is prevented from being damaged due to overlarge local stress.

In some embodiments, the strength of the cushion 50 is greater than that of the top cover 10, and the cushion 50 with higher strength can effectively protect the top cover 10 by dispersing the stress applied to the top cover 10 by the cushion 50.

By force analysis, the total tension F borne by the bolt ₂ The method comprises the following steps:

wherein F is the working load of the bolt during working, F ₀ C, pretightening force applied to the bolt after the bolt is screwed _b For the rigidity of the bolt C _m For the rigidity of the top cover,

the relative rigidity of the bolt is shown, and the value range of the relative rigidity of the bolt is 0.2-0.3 when the buffer gasket is not arranged or is made of metal.

According to the requirements of the related technical specifications, when the pre-tightening force is increased (the increasing amplitude is generally not more than 30%), the increasing amplitude of the total load borne by the bolts 30 does not exceed the increasing amplitude of the pre-tightening force, the strength of the buffer backing plate 50 is greater than that of the top cover 10, and the difference of the strength of the buffer backing plate and the pre-tightening force is greater than the increasing amplitude of the pre-tightening force, so that the force acting on the top cover can be effectively reduced. In some modes, considering the welding requirement of the top cover, the yield strength of the material of the top cover generally does not exceed 235Mpa, the material of the buffer backing plate can be Q345 steel, the yield strength of the material is more than or equal to 345Mpa, and the strength of the buffer backing plate is more than 46% higher than that of the top cover.

In one embodiment, the yield strength of the top cover of the pumped storage unit is greater than or equal to 195Mpa, and if the pre-tightening force is increased when the buffer backing plate is not added, the top cover is easy to locally deform. To avoid deformation of the top cover, a cushion plate 50 of a predetermined thickness (for example, 20 mm) is added between the nut 40 and the top cover 10, and the yield strength of the cushion plate 50 is 345Mpa or more. As shown in fig. 4, the stress area 51 of the cushion plate 50 is 2.4 times that of the stress area 41 of the nut 40, the total load acts on the top cover 10 through the cushion plate 50, the stress on the top cover 10 is 127.5Mpa, which is smaller than the yield strength of the top cover, and compared with the stress which is reduced by 40% when the cushion plate is not arranged, the stress on the top cover is effectively reduced by increasing the stress area, the top cover is effectively prevented from being damaged, and meanwhile, the use requirement is met.

As shown in fig. 1 and 3, in some embodiments, a plurality of first screw holes 11 are formed in the top cover 10, a plurality of second screw holes corresponding to the first screw holes 11 are formed in the seat ring 20, and each group of corresponding first screw holes 11 and second screw holes are connected through nuts 40, buffer gaskets 50 and bolts 30.

In some embodiments, each corresponding first screw hole 11 and second screw hole are connected to one buffer pad, and two buffer pads of adjacent groups are not in contact. Namely, a plurality of corresponding first screw holes 11 and second screw holes are formed in the peripheral side of the ring top cover 10 and the peripheral side of the seat ring 20, each group of the first screw holes and the second screw holes are respectively connected through a group of nuts 40, a buffer gasket and bolts 30, the buffer gasket is a discrete component, one buffer gasket is installed in each group of the first screw holes 11 and the second screw holes, the size of each buffer gasket is determined according to the distance between the adjacent screw holes, and two buffer gaskets of the adjacent two groups of screw holes are required to be prevented from being contacted, so that mutual influence is avoided. The discrete buffer gasket has simple structure and convenient replacement and maintenance.

In other modes, the buffer gasket is an integrated annular gasket which is matched with the shape of the top cover 10, and connecting holes are respectively arranged on the buffer gasket at positions corresponding to the first screw holes 11 on the top cover. That is, the buffer gasket may be an integral part, the shape of the integral buffer gasket is an annular gasket corresponding to the shape of the peripheral side of the top cover 10, the annular gasket is provided with connecting holes corresponding to the first screw holes 11, and the integral buffer gasket is directly mounted on the top cover during mounting, and then each bolt and each nut are sequentially mounted, so that the mounting is convenient.

Those of ordinary skill in the art will appreciate that: the discussion of any of the embodiments above is merely exemplary and is not intended to suggest that the scope of the disclosure, including the claims, is limited to these examples; the technical features of the above embodiments or in the different embodiments may also be combined within the idea of the utility model, the steps may be implemented in any order and there are many other variations of the different aspects of the utility model as described above, which are not provided in detail for the sake of brevity.

The embodiments of the utility model are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omission, modification, equivalent replacement, improvement, etc. of the present utility model should be included in the scope of the present utility model.

Claims

1. The utility model provides a pumped storage unit top cap connecting device which characterized in that:

the top cover is connected with the seat ring through bolts and nuts, a buffer gasket is arranged between the nuts and the top cover, and the sectional area of the buffer gasket is larger than that of the nuts.

2. The device of claim 1, wherein the strength of the bumper is greater than the strength of the top cover.

3. The device according to claim 2, wherein the top cover is provided with a plurality of first screw holes, the seat ring is provided with a plurality of second screw holes corresponding to the first screw holes, and each group of corresponding first screw holes and second screw holes are connected through the nuts, the buffer gaskets and the bolts.

4. A device according to claim 3, wherein each corresponding set of first and second screw holes is connected to one buffer pad, and two buffer pads of adjacent sets are not in contact.

5. The device of claim 3, wherein the buffer pad is an integral annular pad which is adapted to the shape of the top cover, and the buffer pad is provided with connecting holes at positions corresponding to the first screw holes on the top cover.

6. The device of claim 1, wherein the cushioning pad has a thickness of 20 millimeters.

7. The apparatus of claim 2 wherein said buffer pad is formed of Q345 steel.