CN114215110A

CN114215110A - Long-distance large-diameter pipeline reserved manhole and using method thereof

Info

Publication number: CN114215110A
Application number: CN202111597024.6A
Authority: CN
Inventors: 杨卫东; 李金楼; 钟向宏; 张远领; 成越; 李建亮; 赵启鹏; 杨令聚; 田立辉; 魏东英
Original assignee: Lianyungang Petrochemical Co Ltd
Current assignee: Lianyungang Petrochemical Co Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2022-03-22
Anticipated expiration: 2041-12-24
Also published as: CN114215110B

Abstract

The invention discloses a reserved manhole of a long-distance large-caliber pipeline and a using method thereof, belonging to the technical field of chemical equipment and comprising a manhole well, the enclosing cover and the pipeline with the flange, the upper portion of manhole well is equipped with the lower flange, through a set of fixed seal spare fixed connection between the upper portion of lower flange and the enclosing cover that has the flange, the centre of the enclosing cover that has the flange is equipped with the through-hole, put into the pressurization metal pole in the through-hole, the upper portion of pressurization metal pole is equipped with the screw thread, the pressurization metal pole locks through internal thread pressure regulating nut, the lower part and the pipeline fixed connection of manhole well, the centre of pressurization metal pole is equipped with symmetrical lug one, the lower part and the inner cup fixed connection of pressurization metal pole, the last circular fixed slot that has seted up of pipeline, be equipped with the inner cup on the circular fixed slot, the inner cup passes through fixing bolt to be fixed, install the graphite gasket between inner cup and the circular fixed slot. The technical problems that an existing long-distance pipeline is inconvenient to weld and poor in purging effect are solved, and the method is mainly applied to the aspect of chemical pipeline conveying.

Description

Long-distance large-diameter pipeline reserved manhole and using method thereof

Technical Field

The invention relates to the technical field of chemical equipment, in particular to a reserved manhole of a long-distance large-diameter pipeline and a using method thereof.

Background

With the rapid development of economy in China, people have higher and higher requirements on living quality and more severe requirements on chemical production, and the giant, energy-saving and environment-friendly effects become the era trend of chemical production. Therefore, the upgrading and upgrading of chemical equipment are performed in China, wherein the pipe diameter of a chemical transmission pipeline is increased, the pipeline distance is prolonged, the application difficulty of a long-distance large-caliber pipeline is high, the problems are troublesome, and the chemical transmission pipeline is not suitable for comprehensive popularization and application.

Firstly, welding is an important construction process of a long-distance large-diameter pipeline, wherein the quality problem of the last welding seam is difficult to guarantee, and the final confirmation of the internal welding seam cannot be carried out in the actual construction process; secondly, the purging effect before the long-distance large-diameter pipeline is put into use is difficult to guarantee, and the common passive method in China is to increase the pressure and the flow of the purging gas and perform long-time and multiple blasting purging, but the purging effect is not ideal for overlong pipelines without flange connections; precooling and preheating are difficult to realize before the pipelines with low-temperature or high-temperature media flowing through the long-distance large-caliber pipelines are put into use, the phenomenon of expansion with heat and contraction with cold of the long-distance large-caliber pipelines is multiplied along with the increase of the distance and the pipe diameter, the inlet sides of the precooling/preheating media enter the outlet sides and are completely gasified/condensed, the heat of the two ports is difficult to balance, and a larger amount of precooling media is filled to bring a large amount of material waste and even pollute the environment; certainly, dirt on the inner wall of a long-distance large-caliber buried pipeline needs manual cleaning operation, low-point liquid drainage operation, material filling and exhausting operation and the like during maintenance, and is difficult to realize or the realization cost is high. At present, no design and related data report for a reserved manhole of a long-distance large-caliber pipeline exist, and a brand new design is needed to solve the difficulty in the prior art.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a long-distance large-caliber pipeline reserved manhole and a using method thereof.

The core part of the invention is the design of a reserved manhole, and the reserved manhole for a long-distance large-caliber pipeline is characterized by comprising a manhole well, an outer cover with a flange and a conveying pipeline, wherein the flange is arranged at the upper part of the manhole well, the upper part of the flange is fixedly connected with the outer cover with the flange through a group of fixed sealing elements, each fixed sealing element comprises a double-nut screw rod, a nut and a sealing washer, and the sealing washer is positioned between the outer cover with the flange and the flange to form sealing, so that the sealing of the manhole is ensured, which is the first sealing. The centre of enclosing cover with flange be equipped with the through-hole, the through-hole in put into the pressurization metal pole, the upper portion of pressurization metal pole be equipped with the screw thread, the pressurization metal pole lock through interior silk pressure regulating nut, the lower part of interior silk pressure regulating nut be equipped with ring seal groove one, the upper portion of enclosing cover with flange on be equipped with ring seal groove two, ring seal groove one and ring seal groove two between be equipped with O shape sealing washer, this is that the second is sealed, mainly used for ensuring the manhole is sealed, prevents that the material in the pipeline from leaking from the manhole, the lower part and the pipeline 23 fixed connection of manhole well, the enclosing cover with flange on be equipped with respectively and sweep gas pipeline and tail gas discharge pipeline, the upper portion of sweeping gas pipeline be equipped with stop valve one, the upper portion and the screwed pipe fixed connection of stop valve one, the upper portion of tail gas emission pipeline be equipped with stop valve two, the upper portion and the screwed pipe two fixed connection of stop valve two, the centre of pressurization metal pole be equipped with the lug of symmetry one, here the lug can cooperate with the crane when installation or maintenance, the lower part and the inner cup fixed connection of pressurization metal pole, pipeline on seted up circular fixed slot, circular fixed slot on be equipped with the inner cup, the inner cup pass through fixing bolt and circular fixed slot fixed, inner cup and circular fixed slot between install the graphite gasket.

Preferably: in order to increase the connection strength, the connection part of the lower part of the manhole shaft and the conveying pipeline is reinforced and fixed through a reinforcing plate.

Preferably: in order to ensure the sealing in the manhole and prevent the leakage of materials in the conveying pipeline, inert gas is filled between the inner cover and the outer cover with the flange. The inert gas communicated in the manhole can be nitrogen, the nitrogen can be connected with a public engineering station in a device area through a threaded pipe in a hose connection or formal connection pipe, the nitrogen can be determined according to the pressure of an internal medium of a long-distance large pipe diameter and is generally slightly lower than the pressure of the internal medium of the long-distance large pipe diameter by 0.05-0.1 MPa, the nitrogen can intermittently flow through the threaded pipe to isolate the cold and heat diffusion of the medium in the long-distance large pipe diameter, and the nitrogen can continuously flow through the threaded pipe to eliminate the accumulation of trace leakage of the medium in the manhole through the connection part of an inner cover of the long-distance large pipe diameter; the gas that leads to in the manhole well can be the air, accessible screwed pipe carries out hose connection or formal takeover connection with the public engineering station in the device district to discharge through sweeping the gas pipeline, but the discharge port threaded connection hose to the safe position, treat that the gas oxygen content of sweeping 19 ~ 22 vol%, can further the people overhaul or install, need carry out abundant analysis to the gas in the well before further logical air and need guarantee combustible gas 0 ~ 0.2 vol%, need to accomplish abundant replacement to the medium that circulates in the big pipeline of long distance before further logical air, its medium oxygen content 18 ~ 22 vol%.

Preferably: in order to periodically detect the pressure change in the manhole, the exhaust gas discharge pipeline on the outer cover with the flange is connected with a pressure gauge.

Preferably, for the convenience of overhauling of personnel, a vertical ladder is arranged in the manhole shaft along the inner shaft wall.

Preferably: in order to increase the contact area between the pressurizing metal rod and the inner cover, a reinforcing rib is arranged at the joint of the pressurizing metal rod and the inner cover.

The manhole is arranged on a long-distance large-diameter conveying pipeline, the device passes through the manhole, material sealing isolation is carried out on an inner cover and an outer cover with a flange and a medium in the pipeline, two symmetrical lifting lugs II are arranged on the outer cover with the flange, the inner cover and the long-distance large-diameter pipeline are in bolt positioning connection, a graphite gasket is arranged on a contact surface, and inert gas filling is carried out between the inner cover and the outer cover with the flange, so that internal corrosion is prevented. Inner cup inner wall flush with the pipeline inner wall and keep smooth, further inner cup is the single-end bolt with long distance heavy-calibre pipeline junction bolt, the nut is located the manhole well, but the length of the single-end bolt of here needs strict control and accurate calculation, must not be longer than long distance heavy-calibre pipeline wall thickness, and inner cup and long distance heavy-calibre pipeline junction pack sealedly, this department connection gap machining precision should be not more than 100 microns, the kinetic energy loss of carrying to the material in the long distance heavy-calibre pipeline under to operating condition of this device of reduction that can be the biggest like this.

Preferably: the lower part of the flange of the long-distance large-diameter manhole device can be provided with a support hanger according to the field condition so as to reduce the stress on the long-distance large-diameter pipeline, and the support hanger at the position needs to fully consider the displacement caused by expansion with heat and contraction with cold of the working condition before and after use.

Preferably: the joint of the pressurizing metal rod and the inner cover is provided with reinforcing ribs, the pressurizing metal rod keeps the central position of the inner cover, and the pressurizing metal rod is vertical to the tangent line of the vertex of the inner cover, on the premise, the number of the reinforcing ribs is not less than three, the reinforcing ribs are symmetrically distributed at an angle between every two reinforcing ribs, and the reinforcing ribs are high-strength reinforcing ribs which can realize supporting and lifting in a fin type or other types;

preferably: the pressure metal rod is connected with the outer cover with the flange through a smooth wall, the machining precision between the metal rod and the outer cover with the flange is within 100 micrometers, graphite powder is required to be supplemented during installation, further, the metal rod positioned on the outer cover with the flange is connected with an inner wire pressure regulating nut, an O-shaped ring is additionally arranged between the inner wire pressure regulating nut and the outer cover with the flange, the pressure metal rod is subjected to vertical downward force through the rotation of the inner wire pressure regulating nut, further, the vertical downward force is uniformly distributed on the inner cover through reinforcing ribs and is conducted to the contact surface of the inner cover and a pipeline, the contact surface gap is further reduced, the strength of the pressure regulating nut is implemented by a hydraulic wrench, and the outer cover with the flange before the pressure regulating nut formally regulates the pressure, and the outer cover with the flange is fastened with a manhole well bolt;

preferably: inner cup, the enclosing cover that has the flange and pressurization metal pole and subsidiary annex can be demolishd, carry out the transformation of cross-over connection pipeline on the basis of flange, can easily realize the material cross-over connection of a plurality of long distance heavy-calibre pipelines of no fire and transport, so the precooling can be connected more easily in the pipeline precooling stage and the medium is preheated or the facility of emptying to the temporary, can realize the segmentation precooling and preheat, increases the precooling and preheats the overall speed and the quality is guaranteed. The installation position of the device is required to be positioned in a factory boundary area, the device cannot be independently arranged at an open and long-term unattended outdoor position, and if the inside of a pipeline is flammable and explosive or toxic and harmful media with serious risk types, regular personnel inspection, timing sampling analysis, real-time gas detection and alarm mechanisms and other safety requirements higher than national regulations are required.

Compared with the prior art, the invention has the beneficial effects that: according to the multi-seal reserved manhole device for the long-distance large-diameter pipeline, provided by the invention, the manual inspection and the pipeline cleaning can be realized after personnel enter the conveying pipeline, and the garbage in the conveying pipeline is directly taken out, so that the safety of upstream and downstream equipment is ensured; the pipeline can be bridged without fire, and the material intercommunication and interconnection among long-distance large-caliber pipelines can be adjusted; the multi-section purging and multi-section pre-cooling preheating can be carried out simultaneously; can realize that the last welding seam operation personnel of long distance big pipe diameter do not have the worry welding inside the pipeline with the outside, personnel withdraw from the convenience to increase the device quantity in appropriate position and can realize the multistage simultaneously construction easily, promote construction quality when improving the construction progress, accord with the needs of modernization construction, be suitable for comprehensive popularization and application.

Drawings

FIG. 1 is an internal structural view of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1A;

FIG. 3 is a partial enlarged view of FIG. 1B;

FIG. 4 is a first top view of the present invention;

FIG. 5 is a second top view of the present invention;

FIG. 6 is a partial enlarged view of FIG. 5C;

fig. 7 is a bottom view of the female wire pressure regulating nut of the present invention.

In the figure: 1, a first threaded pipe; 2, a first stop valve; 3 purging the gas line; 4 pressing the metal rod; 5, internally threading a pressure regulating nut; 6 outer cover with flange; 7, a second threaded pipe; 8, a second stop valve; 9 a tail gas discharge pipeline; 10 double-nut screw rods; 11 a nut; 12 sealing the gasket; 13, a flange; 14, a vertical ladder; 15 manhole wells; 16 reinforcing plates; 17 reinforcing ribs; 18 an inner lid; 19, packing and sealing; 20 fixing the bolt; 21, a circular fixing groove; a 22O-shaped seal ring; 23 conveying a pipeline; 24, lifting a first lug; and 25, lifting a second lifting lug.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Please refer to fig. 1-7:

the utility model provides a manhole is reserved to long distance heavy-calibre pipeline which characterized in that, includes manhole well 15, the enclosing cover 6 and the pipeline 23 that have the flange, the upper portion of manhole well 15 be equipped with flange 13, the upper portion of flange 13 and the enclosing cover 6 that has the flange between through a set of fixed seal spare fixed connection, fixed seal spare include two nut screw rods 10, nut 11 and seal ring 12, wherein seal ring 12 is located the centre formation of the enclosing cover 6 that has the flange and flange 13 and seals, the centre of the enclosing cover 6 that has the flange be equipped with through-hole 6-2, through-hole 6-2 in put into pressurization metal pole 4, the upper portion of pressurization metal pole 4 be equipped with the screw thread, pressurization metal pole 4 lock through interior screw pressure regulating nut 5, the lower part of interior screw nut 5 be equipped with annular seal groove one 5-1, the upper portion of enclosing cover 6 with the flange on be equipped with annular seal groove two 6-1, annular seal groove one 5-1 and annular seal groove two 6-1 between be equipped with O shape sealing washer 22, the lower part and pipeline 23 fixed connection of manhole wall of a well 15, enclosing cover 6 with the flange on be equipped with purge gas pipeline 3 and exhaust emission pipeline 9 respectively, the upper portion of purge gas pipeline 3 be equipped with stop valve one 2, the upper portion and the screwed pipe one 1 fixed connection of stop valve one 2, the upper portion of exhaust emission pipeline 9 be equipped with stop valve two 8, the upper portion and the screwed pipe two 7 fixed connection of stop valve two 8, the centre of pressurization metal pole 4 be equipped with lug 24, the lower part and the inner cup 18 fixed connection of pressurization metal pole 4, pipeline 23 on seted up circular fixed slot 21, circular fixed slot 21 on be equipped with inner cup 18, inner cup 18 fixed with circular fixed slot 21 through fixing bolt 20, inner cup 18 and circular fixed slot 21 between install graphite gasket 19, the junction of manhole well 15 lower part and pipeline 23 strengthen fixedly through reinforcing plate 16, inner cup 18 and the enclosing cover 6 that has the flange between carry out inert gas and fill, the exhaust emission pipeline 9 on the enclosing cover 6 that has the flange connect the manometer, manhole well 15 in set up along interior well wall companion ladder 14, pressurization metal pole and inner cup junction set up the strengthening rib.

The working principle of the invention is as follows: installing a reserved manhole of a long-distance large-diameter pipeline on a conveying pipeline; when the last welding seam of the conveying pipeline 23 needs to be welded, people can enter the conveying pipeline through the manhole well 15 at the moment, the internal thread pressure regulating nut 5 on the outer cover 6 with the flange is taken down by a wrench before entering the conveying pipeline, then the nuts 11 are taken down one by the wrench, then the outer cover 6 with the flange is separated from the flange 13 by pulling the lifting lug II 25 by a crane, then the fixing bolt 20 on the inner cover 18 is taken down, the lifting lug I24 is pulled by the crane, then the pressurizing metal rod 4 and the inner cover 18 are taken out together, then constructors are lowered into the conveying pipeline 23 through a shaft wall vertical ladder to weld the inside and the outside simultaneously, and the welding seam is accurately confirmed. When the conveying pipeline 23 needs to be purged, the design of the reserved manhole can be passed at the moment, and the multi-section purging can be carried out simultaneously, so that the purging quality is guaranteed while the working efficiency is improved, and the material waste is reduced while the purging quality is guaranteed.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides a manhole is reserved to long distance heavy-calibre pipeline, its characterized in that, includes manhole well (15), has enclosing cover (6) and pipeline (23) of flange, the upper portion of manhole well (15) be equipped with flange (13), flange (13) and enclosing cover (6) that have the flange between through a set of fixed seal fixed connection, fixed seal include two nut screw (10), nut (11) and seal ring (12), wherein seal ring (12) are located the centre that has enclosing cover (6) and flange (13) of flange and form sealedly, the centre that has enclosing cover (6) of flange be equipped with through-hole (6-2), through-hole (6-2) in put into pressurization metal pole (4), the upper portion of pressurization metal pole (4) be equipped with the screw thread, pressurization metal pole (4) lock through internal thread pressure regulating nut (5), the lower part of the internal thread pressure regulating nut (5) is provided with a first annular sealing groove (5-1), the upper part of the outer cover (6) with the flange is provided with a second annular sealing groove (6-1), an O-shaped sealing ring (22) is arranged between the first annular sealing groove (5-1) and the second annular sealing groove (6-1), the lower part of the manhole well (15) is fixedly connected with a conveying pipeline (23), the outer cover (6) with the flange is respectively provided with a purging gas pipeline (3) and a tail gas discharge pipeline (9), the upper part of the purging gas pipeline (3) is provided with a first stop valve (2), the upper part of the first stop valve (2) is fixedly connected with the first threaded pipe (1), the upper part of the tail gas discharge pipeline (9) is provided with a second stop valve (8), and the upper part of the second stop valve (8) is fixedly connected with the second threaded pipe (7), the middle of the pressurizing metal rod (4) is provided with symmetrical lifting lugs I (24), the lower portion of the pressurizing metal rod (4) is fixedly connected with the inner cover (18), the conveying pipeline (23) is provided with a circular fixing groove (21), the circular fixing groove (21) is provided with the inner cover (18), the inner cover (18) is fixed with the circular fixing groove (21) through a fixing bolt (20), and a graphite gasket (19) is arranged between the inner cover (18) and the circular fixing groove (21).

2. A long-distance large-diameter pipe reserved manhole according to claim 1, wherein the joint of the lower part of the manhole (15) and the conveying pipeline (23) is reinforced and fixed by a reinforcing plate (16).

3. A long distance large diameter pipe manhole according to claim 1, wherein the inner cover (18) and the outer cover (6) with flange are filled with inert gas.

4. A long-distance large-diameter pipe reserved manhole according to claim 1, wherein the exhaust gas discharge pipeline (9) on the outer cover (6) with the flange is connected with a pressure gauge.

5. A long-distance large-diameter pipe reserved manhole according to claim 1, wherein a vertical ladder (14) is arranged in the manhole (15) along the inner wall of the manhole.

6. A long-distance large-diameter pipe preformed manhole according to claim 1, wherein a reinforcing rib (17) is arranged at the joint of the pressurizing metal rod (4) and the inner cover.

7. A use method of a reserved manhole of a long-distance large-caliber pipeline comprises the following steps:

step (1): installing a long distance large diameter pipe reserve manhole according to claims 1 to 3 on a conveying pipe (23);

step (2): when the last welding seam of the conveying pipeline (23) needs to be welded, people can enter the conveying pipeline through the manhole shaft (15), then go down to the conveying pipeline (23) through the well wall vertical ladder (14) to weld the inside and the outside simultaneously, and accurately confirm the welding seam.

And (3): when the conveying pipeline needs to be purged, the multi-section purging can be simultaneously performed through the design of the reserved manhole.