An auxiliary structure for filling and grouting the internal corner of a turbine volute and a method for filling and grouting

Abstract

The present invention discloses an auxiliary structure for backfill grouting of the inner corner of a turbine volute and a backfill grouting method, which makes full use of the inner side of the stay ring as the construction space, optimizes the layout of the grouting pipelines, reduces the work of arranging the grouting pipes, reduces the grouting difficulty, and at the same time reduces the influence on other equipment pipelines, steel bars and concrete pouring construction. The structure includes temporary support seats, inner templates and grouting pipes. A number of temporary support seats and inner templates are arranged around the lower part of the stay ring. The inner templates are vertically arranged inside the temporary support seats. The grouting pipes extend from the inner side of the stay ring through the inner templates and the gaps between adjacent temporary support seats to the inner corner part of the volute. The method steps include installing inner templates inside the temporary support seats; opening holes in the inner templates to install grouting pipes; leading an exhaust pipe upward at the position of the exhaust hole of the stay ring; performing backfill grouting on the inner corner part 6 of the volute through the grouting pipes; cutting off the exposed parts of the grouting pipelines and the exhaust pipe.

Description

Technical Field

[0001] The present invention relates to the corner backfill grouting technology of hydropower stations and large pumping stations, and particularly to the technical field of the corner backfill grouting of the turbine volute. Background Art

[0002] For most power stations, the volute and the surrounding concrete need to jointly bear the internal water pressure of the volute. The dense pouring of the surrounding concrete is crucial for the structural safety. The corner part of the volute needs to be backfilled and grouted to ensure dense pouring. Generally, the requirements for the corner backfill grouting of the volute and the volute pressure relief are as follows: The backfill grouting can be carried out 28 days after the concrete below the installation elevation is poured. The volute can be depressurized 28 days after the pouring of the last bin of the entire surrounding concrete is completed and 7 days after the backfill grouting is completed. According to the statistical analysis of the corner backfill grouting methods of the recently built hydropower stations, especially the high-head pumped storage power stations that mostly adopt the volute pressure-maintaining pouring of the surrounding concrete, in many power stations, the corner backfill grouting of the volute is carried out by embedding grouting boxes on the surface of the corner of the volute and leading them to the turbine floor through grouting pipes. When the concrete is poured to the turbine floor, the grouting construction is carried out. This grouting method has a long grouting pipeline, is easy to be blocked, resulting in poor grouting effect; there are many grouting boxes and grouting pipes arranged, the construction is complex; and there are many intersections with other equipment pipelines and steel bar arrangements, resulting in many construction interferences. Summary of the Invention

[0003] The present invention is to solve the above deficiencies of the existing grouting methods, and provides an auxiliary structure for the corner backfill grouting of the turbine volute and a backfill grouting method based on this structure, which makes full use of the inner side of the stay ring as the construction space, optimizes the layout of the grouting pipeline, reduces the layout work of the grouting pipe, reduces the grouting difficulty, and at the same time reduces the influence on other equipment pipelines, steel bars and concrete pouring construction.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] An auxiliary structure for the corner backfill grouting of the turbine volute of the present invention, the structure is used for the backfill grouting of the corner part of the volute between the inner side of the volute and the stay ring, and includes a temporary support seat, an inner formwork and a grouting pipe. A number of temporary support seats and inner formworks are arranged around the lower part of the stay ring. The inner formwork is vertically arranged inside the temporary support seat. The grouting pipe extends from the inner side of the stay ring through the inner formwork and the gap between adjacent temporary support seats to the corner part of the volute in sequence.

[0006] Preferably, the inlet end of the grouting pipe is located inside the stay ring and bends upward, and the outlet end of the grouting pipe passes through the inner formwork and the gap between adjacent temporary support seats in sequence and inserts into the corner part of the volute.

[0007] Preferably, a number of exhaust holes are arranged equidistantly along the top of the stay ring. An exhaust pipe is provided at the inner side of the stay ring at the position of the exhaust holes. The inlet of the exhaust pipe is connected to the exhaust hole, and one end of the outlet of the exhaust pipe is bent upward.

[0008] Preferably, the inlet of the grouting pipe is higher than the outlet of the exhaust pipe, and the outlet of the exhaust pipe is higher than the highest point of the fillet part of the volute.

[0009] Preferably, the diameter of the grouting pipe is 50 mm, the interval distance of the grouting pipe along the circumferential direction of the stay ring is 1 m, and the distance from the end of the grouting pipe located inside the fillet part of the volute to the top of the fillet part of the volute is 100 mm.

[0010] Preferably, the interval distance of the exhaust holes along the circumferential direction of the stay ring is 1 m, and the diameter of the exhaust holes is 20 mm.

[0011] The present invention also provides a method for backfill grouting of the fillet of a turbine volute, which is characterized in that the method includes the following steps:

[0012] Step 1: Install the stay ring and the volute, and support the stay ring with a temporary support seat.

[0013] Step 2: After the installation of the steel bars and the mechanical and electrical pipelines is completed, install the inner formwork inside the temporary support seat.

[0014] Step 3: Open holes in the inner formwork to install the grouting pipe. The grouting pipe extends through the space between each temporary support seat to a position about 100 mm away from the top of the fillet part of the volute.

[0015] Step 4: Connect the exhaust pipe upward at the position of the exhaust hole of the stay ring.

[0016] Step 5: Pour the concrete below the installation elevation. After the pouring is completed, the concrete above the installation elevation can be constructed.

[0017] Step 6: After 28 days from the completion of the pouring of the concrete below the installation elevation, backfill grout the fillet part 6 of the volute through the grouting pipe. The grouting material is cement mortar.

[0018] Step 7: After 7 days from the completion of the backfill grouting, cut off the exposed parts of the grouting pipeline and the exhaust pipe.

[0019] Step 8: Plug the exhaust holes on the stay ring according to the requirements of the turbine manufacturer.

[0020] The beneficial effects of the present invention are as follows: The grouting pipe is arranged by utilizing the inner space of the stay ring, the length of the grouting pipe is short, and the layout of the grouting pipeline is simple; the grouting pressure is small, the grouting material is cement mortar, the grouting is easy, and the reliability of the grouting quality is improved; the interference between the grouting pipeline and other working surfaces during construction is less. Description of the Drawings

[0021] Figure 1 This is a schematic structural diagram of an auxiliary structure for backfill grouting at the inner corner of a turbine volute according to the present invention.

[0022] Figure 2 It is Figure 1 a partial enlarged schematic view at the "A" position of

[0023] The markings in the figure are as follows:

[0024] 1. Stay ring; 2. Volute; 3. Temporary support; 4. Inner formwork; 5. Grouting pipe; 6. Inner corner part of the volute; 7. Vent hole; 8. Vent pipe; 9. Lower part of concrete; 10. Upper part of concrete. Specific implementation mode

[0025] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation modes.

[0026] As Figure 1 shown, for an auxiliary structure for backfill grouting at the inner corner of a turbine volute according to the present invention, the structure is used for backfill grouting of the inner corner part 6 of the volute 2 between the inner side of the volute 2 and the stay ring 1. It is characterized in that it includes a temporary support seat 3, an inner formwork 4 and a grouting pipe 5. A number of temporary support seats 3 and inner formworks 4 are arranged around the lower part of the stay ring 1. The inner formwork 4 is vertically arranged inside the temporary support seat 3. The grouting pipe 5 extends from the inner side of the stay ring 1 through the inner formwork 4 and the gap between adjacent temporary support seats 3 to the inner corner part 6 of the volute.

[0027] The inlet end of the grouting pipe 5 is located inside the stay ring 1 and bends upward. The outlet end of the grouting pipe 5 passes through the inner formwork 4 and the gap between adjacent temporary support seats 3 in sequence and is inserted into the inner corner part 6 of the volute.

[0028] A number of vent holes 7 are arranged equidistantly along the top of the stay ring 1. An exhaust pipe 8 is provided inside the stay ring 1 at the position of the vent hole 7. The inlet of the exhaust pipe 8 is connected to the vent hole 7, and the outlet end of the exhaust pipe 8 bends upward.

[0029] The inlet of the grouting pipe 5 is higher than the outlet of the exhaust pipe 8, and the outlet of the exhaust pipe 8 is higher than the highest point of the inner corner part 6 of the volute.

[0030] The diameter of the grouting pipe 5 is 50 mm. The interval distance of the grouting pipe 5 along the circumferential direction of the stay ring 1 is 1 m. The end of the grouting pipe 5 located inside the inner corner part 6 of the volute is 100 mm away from the top of the inner corner part 6 of the volute.

[0031] The interval distance of the vent holes 7 along the circumferential direction of the stay ring 1 is 1 m, and the diameter of the vent holes 7 is 20 mm.

[0032] The present invention also provides a method for backfill grouting at the inner corner of a turbine volute. The method includes the following steps:

[0033] Step 1: Install the stay ring 1 and the volute 2, and support the stay ring 1 with the temporary support base 3.

[0034] Step 2: After the installation of steel bars and mechanical and electrical pipelines is completed, install the inner formwork 4 inside the temporary support base 3.

[0035] Step 3: Open holes in the inner formwork 4 to install the grouting pipe 5. The grouting pipe 5 extends through the space between each temporary support base 3 to a position about 100 mm above the top of the volute fillet part 6.

[0036] Step 4: Connect the exhaust pipe 8 upward at the position of the exhaust hole 7 of the stay ring 1.

[0037] Step 5: Pour the concrete 9 below the installation elevation. After the pouring is completed, the concrete 10 above the installation elevation can be constructed.

[0038] Step 6: 28 days after the pouring of the concrete 9 below the installation elevation is completed, backfill grout the volute fillet part 6 through the grouting pipe 5. The grouting material is cement mortar.

[0039] Step 7: 7 days after the completion of the backfill grouting, cut off the exposed parts of the grouting pipeline 5 and the exhaust pipe 8.

[0040] Step 8: Plug the exhaust hole 7 on the stay ring according to the requirements of the turbine manufacturer.

[0041] The technical solution of this application utilizes the inner space of the stay ring to arrange the grouting pipe. The grouting pipe is short, and the grouting pipeline layout is simple; the grouting pressure is small, the grouting material is cement mortar, the grouting is easy, and the reliability of the grouting quality is improved; the interference between the grouting pipeline and other working surfaces during construction is less.

[0042] The grouting layout and construction method of this application have the following advantages:

[0043] (1) Short grouting pipeline and simple layout: Utilize the inner space of the stay ring to arrange the grouting pipeline, avoiding the long pipeline and complex measures such as setting grouting boxes caused by leading the grouting pipeline to the turbine floor in the past.

[0044] (2) Easy grouting and improved reliability of grouting quality: Since the grouting pipeline is short and the bending is simple, a relatively small grouting pressure can be used to make the cement mortar enter the fillet part; the exhaust pipe is short, which is convenient for observing the grouting effect and improving the reliability of the grouting quality.

[0045] (3) Less construction interference: The grouting pipeline and the exhaust pipe are led to the outside of the concrete placement surface through the shortest path, reducing the layout interference between the pipeline and the steel bars and pipelines of other working surfaces. The grouting equipment is arranged inside the stay ring, reducing the interference with the construction of the turbine floor when arranged on the turbine floor.

Claims

1. A method for backfill grouting of the inner corner of a turbine volute, based on an auxiliary structure for backfill grouting of the inner corner of the turbine volute, which is used for backfill grouting of the inner corner part (6) between the inner side of the volute (2) and the stay ring (1). It is characterized in that, It includes temporary support seats (3), inner formwork (4) and grouting pipes (5). A number of temporary support seats (3) and inner formwork (4) are arranged below the surrounding stay ring (1). The inner formwork (4) is vertically arranged inside the temporary support seats (3). The grouting pipes (5) extend from the inside of the stay ring (1) through the inner formwork (4) and the gap between adjacent temporary support seats (3) to the volute fillet part (6). The inlet end of the grouting pipe (5) is located inside the stay ring (1) and bends upward. The outlet end of the grouting pipe (5) passes through the inner formwork (4) and the gap between adjacent temporary support seats (3) and is inserted into the volute fillet part (6). A number of exhaust holes (7) are arranged equidistantly along the top of the stay ring (1). An exhaust pipe (8) is provided inside the stay ring (1) at the position of the exhaust holes (7). The inlet of the exhaust pipe (8) is connected to the exhaust holes (7), and the outlet end of the exhaust pipe (8) bends upward. The method includes the following steps: Step 1, install the stay ring (1) and the volute (2), and support the stay ring (1) with the temporary support seats (3). Step 2, after the installation of steel bars and mechanical and electrical pipelines is completed, install the inner formwork (4) inside the temporary support seats (3). Step 3, open holes in the inner formwork (4) to install the grouting pipes (5). The grouting pipes (5) extend through the space between each temporary support seat (3) to a position 100 mm above the top of the volute fillet part (6). Step 4, lead the exhaust pipe (8) upward at the position of the exhaust holes (7) of the stay ring (1). Step 5, pour the concrete (9) below the installation elevation. After the pouring is completed, the concrete (10) above the installation elevation can be constructed. Step 6, 28 days after the pouring of the concrete (9) below the installation elevation is completed, backfill grout the volute fillet part (6) through the grouting pipes (5). The grouting material is cement mortar. Step 7, 7 days after the backfill grouting is completed, cut off the exposed parts of the grouting pipes (5) and the exhaust pipes (8). Step 8, plug the exhaust holes (7) on the stay ring according to the requirements of the turbine manufacturer.

2. The method for backfill grouting of the inner corner of a turbine volute according to claim 1, characterized in that, The inlet of the grouting pipe (5) is higher than the outlet of the exhaust pipe (8), and the outlet of the exhaust pipe (8) is higher than the highest point of the volute fillet part (6).

3. The method for backfill grouting of the inner corner of a turbine volute according to claim 1, characterized in that, The diameter of the grouting pipe (5) is 50 mm, and the interval distance of the grouting pipes (5) along the circumferential direction of the stay ring (1) is 1 m.

4. The method for backfill grouting of the inner corner of a turbine volute according to claim 1, characterized in that, The interval distance of the exhaust holes (7) along the circumferential direction of the stay ring (1) is 1 m, and the diameter of the exhaust holes (7) is 20 mm.

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