阅读说明：本技术 一种抗土质沉降的出户埋地管的施工方法 (Construction method of anti-soil-settlement underground pipe for going out of home ) 是由 李生兵 杨毅鸥 王丽芳 廖卫超 詹皓淇 李雅倩 郑婷 陈洁 胡军 陈忠 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种抗土质沉降的出户埋地管的施工方法,包括标注出户埋地管的标高及铸铁伸缩管件的高度；第一铸铁管连接第一鸭嘴弯头和防水套管后与第二鸭嘴弯头和第一柔性管件连接头连接；第一柔性管件连接头与铸铁伸缩管件连接并安装限位装置；铸铁伸缩管件的另一端与第二柔性管件连接头连接；第二柔性管件连接头与第三鸭嘴弯头连接；第三鸭嘴弯头的另一端与第三柔性管件连接头连接；第三柔性管件连接头与第二铸铁管连接；第二铸铁管的另一端与第四柔性管件连接头连接；第四柔性管件连接头与第三铸铁管连接,第三铸铁管的另一端连到雨废水井中。本发明的施工方法能大大提高出户埋地铸铁管的抗土质沉降能力,减少因土质沉降导致的断管问题。(The invention discloses a construction method of an out-of-home buried pipe with soil settlement resistance, which comprises the steps of marking the elevation of the out-of-home buried pipe and the height of a cast iron telescopic pipe fitting; the first cast iron pipe is connected with the first duckbill elbow and the waterproof casing pipe and then connected with the second duckbill elbow and the first flexible pipe connector; the first flexible pipe fitting connector is connected with the cast iron telescopic pipe fitting and is provided with a limiting device; the other end of the cast iron telescopic pipe fitting is connected with a second flexible pipe fitting connector; the second flexible pipe fitting connector is connected with the third duckbill elbow; the other end of the third duck-bill elbow is connected with a third flexible pipe connector; the third flexible pipe fitting connector is connected with the second cast iron pipe; the other end of the second cast iron pipe is connected with a fourth flexible pipe connector; and the fourth flexible pipe fitting connector is connected with a third cast iron pipe, and the other end of the third cast iron pipe is connected into the rainwater wastewater well. The construction method can greatly improve the soil sedimentation resistance of the household buried cast iron pipe and reduce the problem of pipe breakage caused by soil sedimentation.)

1. A construction method of an out-of-home buried pipe with soil settlement resistance is characterized by comprising the following steps:

s1, calculating the height of the indoor and outdoor walls to be adjusted according to the elevation of the underground pipes marked out of the house on the drawing and the height of the cast iron telescopic pipe fittings, and adjusting the height of the waterproof casing pipe when embedding;

s2, connecting a first vertical cast iron pipe with a first duckbill elbow, connecting the first duckbill elbow with a second duckbill elbow after the first duckbill elbow is out of an outer wall through a waterproof sleeve, and connecting the second duckbill elbow with a first flexible pipe connector which is vertically arranged in the vertical direction;

s3, connecting the other end of the first flexible pipe fitting connector with a cast iron telescopic pipe fitting, and connecting the other end of the cast iron telescopic pipe fitting with a second flexible pipe fitting connector which is vertically arranged; the cast iron telescopic pipe fitting comprises an outer cast iron pipe and an inner cast iron pipe which is in sliding connection with the outer cast iron pipe through lubricating oil;

a first rubber sealing ring at the joint between the flange gland bearing pipe of the first flexible pipe fitting connector and the front end flange gland of the first flexible pipe fitting connector is connected with the vertical pipe of the second duckbill elbow, and a second rubber sealing ring at the joint between the flange gland bearing pipe of the first flexible pipe fitting connector and the rear end flange gland of the first flexible pipe fitting connector is connected with the upper end of the outer cast iron pipe; a third rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the front end flange gland of the second flexible pipe connector is connected with the lower end of the inner side cast iron pipe; when soil settlement occurs in a certain range, the cast iron telescopic pipe fitting can play a certain telescopic space, and the longitudinal shearing force of the soil settlement on the cast iron telescopic pipe fitting is reduced;

s4, a fourth rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the rear flange gland of the second flexible pipe connector is connected with a third duckbill elbow;

s5, connecting the other end of the third duckbill elbow with a fifth rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally placed third flexible pipe connector and a flange gland at the front end of the third flexible pipe connector;

s6, a sixth rubber sealing ring at the joint between the flange gland bearing pipe of the third flexible pipe connector and the rear flange gland of the third flexible pipe connector is connected with a horizontal second cast iron pipe;

s7, connecting the other end of the second cast iron pipe with a seventh rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally-placed fourth flexible pipe connector and a flange gland at the front end of the fourth flexible pipe connector;

s8, an eighth rubber sealing ring at the joint between a flange gland bearing pipe of a fourth flexible pipe connector and a flange gland at the rear end of the fourth flexible pipe connector is connected with a horizontal third cast iron pipe, and the other end of the third cast iron pipe is connected into the rainwater wastewater well;

the flange gland bearing pipe of the third flexible pipe connector and the flange gland bearing pipe of the fourth flexible pipe connector are provided with upwards-protruding groove cavities at two ends close to the rubber sealing ring, and the straight pipe connected with the third flexible pipe connector and the fourth flexible pipe connector is formed to have larger expansion and inclination movable space with an angle in the groove cavities.

2. The method as claimed in claim 1, wherein a stopper is further installed between the first flexible pipe connector and the second flexible pipe connector to prevent the outer cast iron pipe and the inner cast iron pipe of the cast iron telescopic pipe from being pulled apart in step S3.

3. The construction method of the out-of-home buried pipe with the soil sedimentation resistance, according to claim 2, wherein the limiting device comprises a limiting rod, a first limiting fixing lug formed on a rear end flange gland of the first flexible pipe fitting connector, and a second limiting fixing lug formed on a front end flange gland of the second flexible pipe fitting connector, the limiting rod penetrates through a through hole in the first limiting fixing lug and is in sliding connection with the first limiting fixing lug, and the lower end of the limiting rod is in threaded connection with the second limiting fixing lug and is fixed by a nut;

the top of the limiting rod is provided with a limiting circular plate with the diameter larger than that of the through hole.

4. The method as claimed in claim 3, wherein a distance between the limiting circular plate and the through hole of the first limiting fixing lug is smaller than a distance between the upper end of the inner cast iron pipe and the lower end of the outer cast iron pipe.

5. The method as claimed in claim 1, wherein the inner cast iron pipe has an outer diameter smaller than that of the outer cast iron pipe, and the inner diameter of the second rubber packing at the joint between the flange cover bearing pipe of the first flexible pipe connector and the rear flange cover of the first flexible pipe connector is larger than that of the third rubber packing at the joint between the flange cover bearing pipe of the second flexible pipe connector and the front flange cover of the second flexible pipe connector.

6. The construction method of the out-of-home buried pipe with resistance to soil sedimentation according to any one of claims 1 to 5, wherein the flange gland bearing pipe of each flexible pipe connector and the front end flange gland and the rear end flange gland of each flexible pipe connector are connected and locked through bolts.

Technical Field

The invention relates to the technical field of building construction, in particular to a construction method of an out-of-home buried pipe with soil settlement resistance.

Background

At present, as the number of large public buildings is increased day by day and more energy supply systems are provided, the pipelines of the water supply and drainage system of the large public buildings are abundant, and most of rain waste water systems are made of durable cast iron pipes, so that the rain waste water systems are low in price and strong in corrosion resistance, and are widely accepted and used in the industry for a long time after entering the international market in the 60 s. However, the disadvantages of cast iron pipes are also apparent, brittle, heavy, etc.

The construction schematic diagram of the traditional underground pipe for going out of home is shown in figure 1, after the underground pipe reaches the ground along an indoor vertical pipe and an outdoor vertical pipe, the waterproof casing pipe goes out of home, a B-type direct pipe connection is added, and a long straight pipe section is connected to a rainwater wastewater well.

Although the construction process has links of tamping, sand bedding and the like, in actual construction, soil settlement in later period within one or two years is still serious because of reasons of easy neglect in construction period, improper tamping and the like, and cast iron pipes buried outdoors are easily broken directly as shown in figure 2, so that rework maintenance has to be carried out, and a large amount of labor and materials are wasted.

Disclosure of Invention

Aiming at the situation that the outdoor buried cast iron pipe is broken frequently due to soil settlement, the invention aims to solve the technical problem of providing the construction method of the outdoor buried pipe with the function of soil settlement resistance, greatly eliminating the destructive force of longitudinal shearing force caused by soil settlement on the whole section of the transverse cast iron straight pipe section, improving the soil settlement resistance of the outdoor buried cast iron pipe and reducing the problem of pipe breakage caused by soil settlement.

In order to achieve the purpose, the invention adopts the following technical measures:

a construction method of an out-of-home buried pipe resistant to soil settlement comprises the following steps:

s1, calculating the height of the indoor and outdoor walls to be adjusted according to the elevation of the underground pipes marked out of the house on the drawing and the height of the cast iron telescopic pipe fittings, and adjusting the height of the waterproof casing pipe when embedding;

s2, connecting a first vertical cast iron pipe with a first duckbill elbow, connecting the first duckbill elbow with a second duckbill elbow after the first duckbill elbow is out of an outer wall through a waterproof sleeve, and connecting the second duckbill elbow with a first flexible pipe connector which is vertically arranged in the vertical direction;

s3, connecting the other end of the first flexible pipe fitting connector with a cast iron telescopic pipe fitting, and connecting the other end of the cast iron telescopic pipe fitting with a second flexible pipe fitting connector which is vertically arranged; the cast iron telescopic pipe fitting comprises an outer cast iron pipe and an inner cast iron pipe which is in sliding connection with the outer cast iron pipe through lubricating oil; a first rubber sealing ring at the joint between the flange gland bearing pipe of the first flexible pipe fitting connector and the front end flange gland of the first flexible pipe fitting connector is connected with the vertical pipe of the second duckbill elbow, and a second rubber sealing ring at the joint between the flange gland bearing pipe of the first flexible pipe fitting connector and the rear end flange gland of the first flexible pipe fitting connector is connected with the upper end of the outer cast iron pipe; a third rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the front end flange gland of the second flexible pipe connector is connected with the lower end of the inner side cast iron pipe; when soil settlement occurs in a certain range, the cast iron telescopic pipe fitting can play a certain telescopic space, and the longitudinal shearing force of the soil settlement on the cast iron telescopic pipe fitting is reduced;

s4, a fourth rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the rear flange gland of the second flexible pipe connector is connected with a third duckbill elbow;

s5, connecting the other end of the third duckbill elbow with a fifth rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally placed third flexible pipe connector and a flange gland at the front end of the third flexible pipe connector;

s6, a sixth rubber sealing ring at the joint between the flange gland bearing pipe of the third flexible pipe connector and the rear flange gland of the third flexible pipe connector is connected with a horizontal second cast iron pipe;

s7, connecting the other end of the second cast iron pipe with a seventh rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally-placed fourth flexible pipe connector and a flange gland at the front end of the fourth flexible pipe connector;

s8, an eighth rubber sealing ring at the joint between a flange gland bearing pipe of a fourth flexible pipe connector and a flange gland at the rear end of the fourth flexible pipe connector is connected with a horizontal third cast iron pipe, and the other end of the third cast iron pipe is connected into the rainwater wastewater well; the flange gland bearing pipe of the third flexible pipe connector and the flange gland bearing pipe of the fourth flexible pipe connector are provided with upwards-protruding groove cavities at two ends close to the rubber sealing ring, and the straight pipe connected with the third flexible pipe connector and the fourth flexible pipe connector is formed to have larger expansion and inclination movable space with an angle in the groove cavities.

Further, in step S3, a limiting device is further installed between the first flexible pipe connector and the second flexible pipe connector to ensure that the outer cast iron pipe and the inner cast iron pipe of the cast iron telescopic pipe are not pulled apart.

Preferably, the limiting device comprises a limiting rod, a first limiting fixing lug formed on a rear flange gland of the first flexible pipe fitting connector, and a second limiting fixing lug formed on a front flange gland of the second flexible pipe fitting connector, the limiting rod passes through a through hole in the first limiting fixing lug and is in sliding connection with the first limiting fixing lug, and the lower end of the limiting rod is in threaded connection with the second limiting fixing lug and is fixed by a nut; the top of the limiting rod is provided with a limiting circular plate with the diameter larger than that of the through hole.

Preferably, the distance between the limiting circular plate and the through hole on the first limiting fixing lug is smaller than the distance between the upper end of the inner cast iron pipe and the lower end of the outer cast iron pipe.

Furthermore, the outer diameter of the inner cast iron pipe is smaller than that of the outer cast iron pipe, and the inner diameter of a second rubber sealing ring at the joint between the flange gland bearing pipe of the first flexible pipe connector and the rear end flange gland of the first flexible pipe connector is larger than that of a third rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the front end flange gland of the second flexible pipe connector.

Furthermore, the flange gland bearing pipe of each flexible pipe connector and the front end flange gland and the rear end flange gland of each flexible pipe connector are connected and locked through bolts.

Compared with the traditional method, the construction method of the anti-soil-settlement underground pipe for the household has the advantages that:

1. the problem of soil settlement always exists, and the new city is more serious, the invention greatly enhances the soil settlement resistance of the cast iron pipe when the cast iron pipe is buried outdoors, and reduces the possibility of pipe breakage caused by soil settlement.

2. Compared with the traditional process, the construction of the buried pipeline for going out of home is carried out by using the invention, and although pipe fittings such as the cast iron extension pipe, the duckbill elbow and the like are added, the possibility of repairing the broken pipe caused by soil settlement is greatly reduced, and the labor and the construction period are also saved.

3. The flexible pipe fitting connector further enhances the bending resistance of the connector, and the flexible cast iron pipe fitting, the flexible limiting device thereof and the flexible pipe fitting connector are combined together to realize the maximum soil settlement resistance.

Drawings

Fig. 1 is a construction schematic diagram of a conventional outdoor buried pipe;

fig. 2 is a schematic view of a settlement fracture of a conventional underground pipe for home use;

fig. 3 is a construction schematic diagram of the outdoor buried pipe of the present invention;

FIG. 4 is a graph showing the effect of soil sedimentation;

fig. 5 is a schematic view of the anti-soil subsidence of the underground pipe for household use of the present invention;

FIG. 6 is a schematic view of the connection of the cast iron extension tube of the present invention with a first flexible tube connector and a second flexible tube connector;

FIG. 7 is a schematic structural view of a rear flange gland of a first flexible pipe coupling and a front flange gland of a second flexible pipe coupling of the present invention;

FIG. 8 is a schematic structural view of a front flange gland of a first flexible pipe connector, a rear flange gland of a second flexible pipe connector, and respective flange glands of third and fourth flexible pipe connectors of the present invention;

fig. 9 is a schematic structural diagram of the flexible pipe joint of the present invention.

Detailed Description

As shown in fig. 3-9, the buried pipe for house going out of the invention for resisting soil settlement comprises a first cast iron pipe a, a floor penetrating sleeve D1, a first duckbill elbow B, a waterproof sleeve D2, a cast iron telescopic pipe fitting E and a limiting device F thereof, a flexible pipe fitting connector C, and an improved flange gland of the flexible pipe fitting connector C. The invention relates to a construction method of an out-of-home buried pipe with soil settlement resistance, which comprises the following steps:

step 1, calculating the height of an indoor and outdoor wall needing to be adjusted according to the elevation of an outdoor buried pipe and the height of a cast iron telescopic pipe fitting marked on a drawing, and adjusting the height of a waterproof casing pipe when embedding, wherein in the specific embodiment, a DN100 cast iron pipe is taken as an example, the height of the cast iron telescopic pipe fitting E is about 260mm, and the height difference of two duckbill elbows is about 760 mm.

And 2, connecting the first cast iron pipe A with a first duckbill elbow B after passing through a floor slab sleeve D1, connecting the first duckbill elbow B with a second duckbill elbow after passing out of the outer wall through a waterproof sleeve D2, and connecting the second duckbill elbow with a vertically-arranged first flexible pipe connector in the vertical direction.

Step 3, connecting the other end of the first flexible pipe fitting connector with a cast iron telescopic pipe fitting E, and connecting the other end of the cast iron telescopic pipe fitting E with a second flexible pipe fitting connector which is vertically arranged; the cast iron telescopic tube member E comprises an outer cast iron tube G1 and an inner cast iron tube G2 slidably connected to said outer cast iron tube G1 by means of a lubricating oil.

A first rubber sealing ring at the joint between the flange gland bearing pipe E1 of the first flexible pipe connector and the flange gland E2 at the front end of the first flexible pipe connector is connected with a vertical pipe of the second duckbilled elbow, and a second rubber sealing ring E6 at the joint between the flange gland bearing pipe E1 of the first flexible pipe connector and the flange gland E3 at the rear end of the first flexible pipe connector is connected with the upper end of the outer cast iron pipe G1; a third rubber sealing ring E7 at the joint between the flange gland bearing pipe of the second flexible pipe joint and the front end flange gland of the second flexible pipe joint is connected with the lower end of the inner side cast iron pipe G2; when soil settlement in a certain range occurs, the cast iron telescopic pipe fitting E can play a certain telescopic space, and longitudinal shearing force of the soil settlement on the cast iron telescopic pipe fitting E is reduced. The front flange gland of the second flexible pipe connector and the rear flange gland E3 of the first flexible pipe connector have the same structure. The flange gland bearing pipe of each flexible pipe connector is the same as the flange gland bearing pipe E1 of the first flexible pipe connector in structure. The rubber sealing ring of each flexible pipe fitting connector has the same structure as the second rubber sealing ring E6 at the joint between the flange gland bearing pipe E1 of the first flexible pipe fitting connector and the rear end flange gland E3 of the first flexible pipe fitting connector.

As shown in fig. 6, the cast iron telescopic tube E is a longitudinal telescopic cast iron tube section, and the straight tube of the duckbill elbow at the upper end thereof is connected with the first rubber sealing ring. The first flexible pipe connector and the second flexible pipe connector are respectively locked with the front flange gland and the rear flange gland through the flange gland bearing pipe E1.

And a limiting device F is further arranged between the first flexible pipe fitting connector and the second flexible pipe fitting connector and is used for ensuring that the outer cast iron pipe G1 and the inner cast iron pipe G2 of the cast iron telescopic pipe fitting E are not pulled away. Stop device includes gag lever post 10, form the first spacing fixed ear 20 on the rear end flange gland E3 of first flexible pipe fitting connector, form the spacing fixed ear of second on the front end flange gland of the flexible pipe fitting connector of second, gag lever post 10 pass the through-hole on the first spacing fixed ear 20 and with first spacing fixed ear sliding connection, the lower extreme of gag lever post 10 and the spacing fixed ear threaded connection of second are fixed with the nut. The top of the limiting rod 10 is provided with a limiting circular plate with the diameter larger than that of the through hole. The distance F1 between the limiting circular plate and the through hole on the first limiting fixing lug is smaller than the distance F2 (the length of the limit movement of the cast iron telescopic pipe fitting) between the upper end of the inner cast iron pipe G2 and the lower end of the outer cast iron pipe G1, namely F1< F2, so that the maximum telescopic amount of the cast iron telescopic pipe fitting can be ensured not to exceed the limit to cause pull-out. When soil settlement in a certain range occurs, the cast iron telescopic pipe fitting E can play a certain telescopic space, and direct longitudinal shearing force of the soil settlement on the long straight pipe is reduced.

As shown in fig. 7 and 8, 3 limiting fixing lugs 20 are symmetrically added to the flange pressing cover E3 compared with the flange pressing cover E2, the limiting fixing lugs 20 on the second flexible pipe connector are provided with threaded holes E5, the flange pressing cover on each flexible pipe connector is provided with 3 threaded holes E4, and the flange pressing cover bearing pipe of each flexible pipe connector and the respective front end flange pressing cover and rear end flange pressing cover are connected through the threaded holes E4 by bolts 40.

Solid butter or other solid lubricating oil is filled between the outer cast iron pipe G1 and the inner cast iron pipe G2 to play a role in lubricating the extension pipe. The outer diameter of the inner cast iron pipe G2 is smaller than that of the outer cast iron pipe G1, the inner diameter of a second rubber sealing ring E6 at the joint between the flange gland bearing pipe of the first flexible pipe connector and the rear end flange gland of the first flexible pipe connector is larger than that of a third rubber sealing ring E7 at the joint between the flange gland bearing pipe of the second flexible pipe connector and the front end flange gland of the second flexible pipe connector, and water leakage is prevented.

And 4, connecting a fourth rubber sealing ring at the joint between the flange gland bearing pipe of the second flexible pipe connector and the rear end flange gland of the second flexible pipe connector with a third duckbill elbow. The rear end flange gland of the second flexible pipe connector has the same structure as the front end flange gland E2 of the first flexible pipe connector.

And 5, connecting the other end of the third duckbill elbow with a fifth rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally placed third flexible pipe connector and a front end flange gland of the third flexible pipe connector.

And 6, connecting a sixth rubber sealing ring at the joint between the flange gland bearing pipe of the third flexible pipe connector and the rear flange gland of the third flexible pipe connector with the horizontal second cast iron pipe.

And 7, connecting the other end of the second cast iron pipe with a seventh rubber sealing ring at the joint between a flange gland bearing pipe of a horizontally-arranged fourth flexible pipe connector and a front-end flange gland of the fourth flexible pipe connector.

And 8, connecting an eighth rubber sealing ring at the joint between the flange gland bearing pipe of the fourth flexible pipe connector and the rear flange gland of the fourth flexible pipe connector with a horizontal third cast iron pipe, wherein the other end of the third cast iron pipe is connected into the rainwater wastewater well.

As shown in fig. 9, the two ends of the flange gland bearing pipe of the third flexible pipe connector and the flange gland bearing pipe of the fourth flexible pipe connector, which are close to the rubber sealing ring, are provided with groove cavities 30 protruding upwards, so that the straight pipe connected with the third flexible pipe connector and the fourth flexible pipe connector has larger telescopic and inclined movement spaces with angles in the groove cavities. The groove cavity body increases the space of the straight pipe at the flexible pipe connector, greatly increases the movable space of the cast iron straight pipe with an angle, ensures that the cast iron straight pipe has certain angle movement and adjustment in the flexible pipe connector, and enhances the flexible range of the cast iron straight pipe and the flexible pipe connector. In a similar way, the flange gland bearing pipe of the first flexible pipe connector and the flange gland bearing pipe of the second flexible pipe connector have the same structure.

Because the third flexible pipe fitting connector and the fourth flexible pipe fitting connector are not provided with limiting devices, the front flange gland and the rear flange gland on the two flexible pipe fitting connectors are not provided with limiting fixing lugs, and therefore, the structures of the front flange gland and the rear flange gland on the third flexible pipe fitting connector and the fourth flexible pipe fitting connector are the same as the structure of the front flange gland E2 of the first flexible pipe fitting connector.

The construction method of the invention improves the cast iron pipe with the length of 6 meters as shown in figures 1 and 2, but adopts two short pipes for connection, and the flexible pipe connector is added in the middle, thus greatly improving the anti-settling capacity of the straight pipe section. As shown in fig. 4 and 5, when soil subsidence occurs within a certain range, most of subsidence damage can be eliminated by the cast iron telescopic pipe fitting E close to the wall, most of shearing force of longitudinal subsidence of the soil can be eliminated by the cast iron telescopic pipe fitting, and synchronous subsidence of the buried cast iron pipe along with the soil within a certain range can be ensured; secondly, 4 flexible pipe fittings connectors also allow the cast iron pipe to settle unevenly within a small angle range of 1-3 degrees, so that the uneven settlement of soil can be eliminated, the original cast iron pipe with a straight pipe section of nearly 6 meters in length is changed into a short straight pipe, a longitudinal pipe fitting and a straight pipe with nearly 3 meters in length, and the uneven settlement of soil within a certain range can be borne.

In the construction method, the processes of soil compaction, sand bedding and the like in the original construction process are also reserved, and the scale of soil settlement is reduced. The construction method provided by the invention is a construction method for further improving the soil sedimentation resistance of the household buried cast iron pipe.

On the basis of the traditional outdoor buried cast iron pipe, the invention provides the cast iron telescopic pipe fitting and the limiting device thereof, and the destructive force of longitudinal shearing force caused by soil settlement to the whole section of the transverse cast iron straight pipe section is greatly eliminated. The construction method of the invention increases the space of the pipe fitting cavity of the flexible pipe fitting connector on the basis of adding one cast iron telescopic pipe fitting, improves the moving angle and range of the cast iron pipe, improves the flexibility, greatly improves the soil sedimentation resistance of the household buried cast iron pipe by matching with the cast iron telescopic pipe fitting, and reduces the problem of pipe breakage caused by soil sedimentation.

The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can understand that the modifications or substitutions within the technical scope of the present invention should be included in the scope of the present invention.