Combined installation method for embedded parts of water turbine

Abstract

The invention discloses a combined installation method for embedded parts of a water turbine, and relates to the technical field of hydroelectric power stations. The water turbine embedded part combined installation method comprises the following steps that S1, a pressure steel pipe is installed; s2, mounting and fixing the seat ring; s3, a volute is correspondingly installed between the seat ring and the pressure steel pipe; s4, the adjusters are installed, the pressure steel pipe and the adjusters are subjected to full welding, the adjusters and the volute are welded, and welding circular seams are reserved; s5, fixing of the seat ring is relieved, and welding closing is conducted on a welding circular seam at the connecting position of the adjuster and the volute; s6, after the installation elevation and the horizontal deviation of the seat ring are determined and fine adjustment is carried out, the ring seat is fixedly installed; and S7, outer cladding reinforced concrete is poured. According to the combined mounting method for the embedded parts of the water turbine, the problem that the residual stress of the folding seam is large and cannot be effectively released during mounting of the adjuster can be effectively solved, the connecting quality after mounting of the adjuster is guaranteed, and potential safety hazards caused by mounting of the adjuster in the operation process of a power station are eliminated.

Description

Technical Field

[0001] The invention relates to the technical field of hydroelectric power stations, and in particular to a combined installation method for embedded parts of a water turbine. Background Art

[0002] When installing embedded parts of turbines in hydropower stations, the seat ring, volute, pressure steel pipe and joint are often installed independently, and the joint is installed as the last component of the turbine embedded parts. There are three installation methods according to different installation processes.

[0003] Method 1: First, install and weld the pressure steel pipe and pour the outer layer of reinforced concrete, then install and weld the seat ring and volute and pour the outer layer of reinforced concrete, reserve a space for the joint installation and welding operation (phase II concrete pit), and wait for the seat ring and volute outer layer concrete solidification period to expire before installing and welding the joint in the phase II pit, and then pour the reinforced concrete of the phase II pit to fill it up; Method 2: First, install and weld the pressure steel pipe and pour the outer layer of reinforced concrete, and then install the seat ring, volute and joint in sequence at the same time, do not reserve the phase II concrete pit, reserve the last closing seam between the joint and the volute without welding, and wait for the embedded parts After all the concrete pouring is completed and rises to the generator layer, the welding of the weld can be started; Method three: First carry out the installation welding of the pressure steel pipe and pour the outer layer of reinforced concrete, and then install the seat ring, volute and joint in order at the same time, leaving the last closing seam between the joint and the volute without welding, wait for the seat ring and volute to be installed and tighten the foundation anchor bolts, and add strong steel structure support at multiple locations around the seat ring and volute, and weld and tighten them with the foundation concrete steel bars, ground anchors, etc., until the seat ring, volute and the ground foundation concrete steel bars, ground anchors, etc. form an integral and strongly fixed state, and finally weld the closing seam between the volute and the joint.

[0004] However, in the above methods, the welding of the last closing seam during the installation of the joint is carried out under strong restraint conditions. The residual stress of the weld is large and cannot be effectively released. Conventional manual hammering can only be used to eliminate the stress, but the effect is limited and unsatisfactory. After welding, the welding residual stress is still very large after testing, and some welding residual stress points are close to or reach the yield point stress. Welding cracks are prone to occur during the welding process, and the processing workload is large. After the unit is put into operation and the flow is flowing, the weld is prone to cracks again under the action of the alternating force of the water flow, which poses a great hidden danger to the safe operation of the power station, and the maintenance and processing are relatively troublesome. Summary of the invention

[0005] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0006] To this end, an embodiment of the present invention proposes a method for jointly installing embedded parts of a turbine, which can effectively solve the problem that the residual stress of the closing seam is large and cannot be effectively released during the installation of the joint, avoid cracks and post-cracks in the weld of the joint, ensure the connection quality after the installation of the joint, and eliminate the safety hazards caused by the installation of the joint during the operation of the power station.

[0007] The method for jointly installing embedded parts of a water turbine according to an embodiment of the present invention comprises the following steps:

[0008] S1: Install the penstock and pour the outer layer of reinforced concrete outside the penstock;

[0009] S2: Cast the seat ring foundation and install and fix the seat ring;

[0010] S3: Install the volute between the seat ring and the pressure steel pipe, and reserve installation space between the volute and the pressure steel pipe;

[0011] S4: Install a joint between the volute and the pressure steel pipe, fully weld the pressure steel pipe and the joint, weld the joint to the volute, and reserve a welding annular seam at the connection position between the joint and the volute;

[0012] S5: Release the fixation of the seat ring, so that the seat ring is in a free stress state, and weld the welding annular seam at the connection position between the joint and the volute to close;

[0013] S6: After determining the installation elevation and horizontal deviation of the seat ring and making fine adjustments, re-fix and install the ring seat;

[0014] S7: Pour the outer layer reinforced concrete at the seat ring position, the volute position, and the joint position between the volute and the pressure steel pipe, monitor the deformation of relevant parts, and dynamically adjust the concrete pouring plan until the overall pouring is completed.

[0015] The combined installation method of embedded parts of a turbine according to an embodiment of the present invention can effectively solve the problem that the residual stress of the closing seam is large and cannot be effectively released during the installation of the joint, avoid the problem of cracks and post-cracks in the weld of the joint, ensure the connection quality after the installation of the joint, and eliminate the safety hazards caused by the installation of the joint during the operation of the power station.

[0016] In some embodiments, in step S1, the penstock is installed in the lower flat section or the inclined section plus the lower flat section of the water diversion tunnel of the hydropower station and is located on the upstream side of the turbine volute. After the penstock is installed in place, the outer casing concrete is poured and contact grouting is performed.

[0017] In some embodiments, in step S1, the penstock includes multiple pipe sections, and the multiple pipe sections need to be welded separately to complete the pre-processing of the penstock. When the penstock is transported to the plant water diversion tunnel for assembly, the penstock and the water diversion tunnel are circumferentially welded and inspected, and the internal support of the penstock is installed.

[0018] In some embodiments, in step S2, the seat ring is configured to be multi-petal, which is assembled and welded into a whole and then hoisted into the machine pit for installation. A seat ring installation platform is set up, and the elevation, level, center and other dimensions are adjusted according to the requirements of the drawings, and radial displacement is reserved for the seat ring.

[0019] In some embodiments, in step S2, the second phase concrete of the seat ring foundation anchor bolts is poured, and after the concrete solidifies, the anchor bolt nuts are tightened to fix the seat ring. In step S5, multiple anchor bolt nuts are loosened one by one to release the tightening of the seat ring.

[0020] In some embodiments, the anchor bolts are arranged in pairs, and when the nuts of the multiple anchor bolts are tightened or loosened one by one, they are screwed one by one in a symmetrical pattern.

[0021] In some embodiments, in step S4, the joint is cut into equal parts, the joint petals are installed and welded in sequence, the annular seam between the joint and the pressure steel pipe is welded, and a welding annular seam is reserved between the joint and the volute.

[0022] In some embodiments, in step S5, when the welding annular seam is closed, a measure for monitoring the displacement and deformation of the seat ring is added, and deformation monitoring is performed on relevant parts of the seat ring until the installation is completed.

[0023] In some embodiments, in step S5, the installation gap of the closed welded annular seam is controlled by using a welding process and assisted by manual hammering to eliminate stress.

[0024] In some embodiments, in step S5, during the closing seam welding process, the distance and orientation between the X and Y marks on the upper and lower ring surfaces of the seat ring and the X and Y reference lines of the unit are monitored, and dial indicators are installed on the upper and lower ring parts of the seat ring to monitor the deformation value of the seat ring, and the closing seam welding process is dynamically adjusted according to the monitored deformation value. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the connection of a pressure steel pipe, a seat ring, a volute and a joint in a method for joint installation of embedded parts of a water turbine according to an embodiment of the present invention.

[0026] Figure 2 It is a schematic diagram of adjusting the installation positions of a seat ring and a volute in a combined installation method for embedded parts of a water turbine according to an embodiment of the present invention.

[0027] Figure 3 It is a cross-sectional schematic diagram of the installation positions of a seat ring, anchor bolts and a volute in a combined installation method for embedded parts of a turbine according to an embodiment of the present invention.

[0028] Reference numerals:

[0029] Penstock 1; seat ring 2; volute 3; joint 4; welded annular seam 5; anchor bolt 6; anchor bolt nut 7. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0031] like Figure 1 , Figure 2 and Figure 3 As shown, the method for combined installation of embedded parts of a water turbine according to an embodiment of the present invention comprises the following steps:

[0032] S1: Install the penstock 1 and pour the outer layer of reinforced concrete outside the penstock 1;

[0033] S2: pouring the seat ring foundation and installing and fixing the seat ring 2;

[0034] S3: Install the volute 3 between the seat ring 2 and the pressure steel pipe 1, and reserve installation space between the volute 3 and the pressure steel pipe 1;

[0035] S4: Install the joint 4 between the volute 3 and the pressure steel pipe 1, fully weld the pressure steel pipe 1 and the joint 4, weld the joint 4 to the volute 3, and reserve a welding annular seam 5 at the connection position between the joint 4 and the volute 3;

[0036] S5: releasing the fixation of the seat ring 2, so that the seat ring 2 is in a free stress state, and welding and closing the welding annular seam 5 at the connection position between the joint 4 and the volute 3;

[0037] S6: After determining the installation elevation and horizontal deviation of the seat ring 2 and making fine adjustments, the ring seat is re-fixed and installed;

[0038] S7: Cast the outer layer reinforced concrete at the position of the seat ring 2, the volute 3 and the joint 4 between the volute 3 and the pressure steel pipe 1, monitor the deformation of the relevant parts, and dynamically adjust the concrete casting plan until the overall casting is completed.

[0039] The method for combined installation of embedded parts of a water turbine according to an embodiment of the present invention performs preliminary fixing of the seat ring 2 and releases the fixation of the seat ring 2 during the installation of the fitting section 4. When the fitting section 4 is installed, the stress at the connection position of the fitting section 4 can drive the seat ring 2 and the volute 3 to move relative to the pressure steel pipe 1, thereby releasing the stress at the position of the fitting section 4. Figure 2 As described above, the dotted line part is a schematic diagram of the position of the seat ring 2 and the volute 3 before the installation of the fitting section 4, and the solid line part is a schematic diagram of the position of the seat ring 2 and the volute 3 after the welding annular seam 5 is welded together. This can effectively solve the problem that the residual stress in the closing seam is large and cannot be effectively released when the fitting section 4 is installed, avoid cracks and post-cracks in the weld of the fitting section 4, ensure the connection quality after the installation of the fitting section 4, eliminate the safety hazards caused by the installation of the fitting section 4 during the operation of the power station, and help to achieve long-term safe and stable operation of the power station.

[0040] In some embodiments, Figure 1 As shown, in step S1, when the pressure steel pipe 1 is installed in the water diversion tunnel, the pressure steel pipe 1 is installed in the lower flat section or the inclined section plus the lower flat section of the water diversion tunnel of the hydropower station, and is located on the upstream side of the turbine volute 3. The cross-section of the pressure steel pipe 1 is circular and the diameter is 4 to 10 meters. The pressure steel pipe 1 is used to connect with the volute 3 through the joint 4. After the pressure steel pipe 1 is installed in place, the outer concrete is poured and contact grouting is performed. By first grouting the pressure steel pipe 1, it is convenient to provide positioning and support for the installation of the volute 3 and the seat ring 2.

[0041] In some embodiments, in step S1, the pressure steel pipe 1 includes N pipe sections, N is an integer not less than 2, the length of a single pipe section is 2 to 4 meters, and the total length is M meters. Multiple pipe sections need to be welded separately to complete the pre-processing of the pressure steel pipe 1. When the pressure steel pipe 1 is transported to the factory water diversion tunnel for assembly, the installation efficiency of the pressure steel pipe 1 is ensured, the pressure steel pipe 1 and the water diversion tunnel are subjected to circumferential welding and circumferential flaw detection, and the pressure steel pipe 1 is internally supported and installed to ensure the connection firmness, installation stability and connectivity sealing of the pressure steel pipe 1.

[0042] In some embodiments, Figure 2 As shown, in step S2, the seat ring 2 is set to be multi-petal, and the multi-petal seat ring 2 is assembled and welded into a whole, then hoisted into the machine pit for installation, and a seat ring 2 installation platform is set up. The elevation, level and center and other dimensions are adjusted according to the requirements of the drawing, and a radial displacement is reserved for the seat ring 2. By setting the radial displacement, when the welding annular seam 5 reserved at the connection position of the joint 4 and the volute 3 is welded and closed, the center of the seat ring 2 can be adjusted by releasing the fixation of the seat ring 2, so as to release the stress at the connection position of the joint 4 and the volute 3 and then the pressure steel pipe 1.

[0043] Optionally, the radial displacement is 3 to 4 mm.

[0044] Optionally, the seat ring 2 is provided with 2 to 6 petals.

[0045] In some embodiments, in step S2, the second phase concrete of the seat ring foundation anchor bolts is poured, and after the concrete solidifies, the anchor bolt nuts 7 are tightened to fix the seat ring 2. In step S5, multiple anchor bolt nuts 7 are loosened one by one to release the fastening of the seat ring 2. The fixed state of the seat ring 2 is adjusted by loosening and tightening the anchor bolt nuts 7 to facilitate operation. In step S6, the nuts of the corresponding multiple anchor bolts 6 are tightened one by one to put the seat ring 2 in a fixed stress state.

[0046] Optionally, a through hole matching the anchor bolt 6 is provided on the bottom plate of the seat ring 2 corresponding to the anchor bolt 6, and the diameter of the through hole is 8 to 10 mm larger than the diameter of the anchor bolt 6. The difference between the radius of the through hole of the bottom plate of the seat ring and the radius of the anchor bolt is the radial displacement reserved for the seat ring 2. To ensure the fixation of the anchor bolt nut 7 to the seat ring 2, the diameter of the inscribed circle corresponding to the outer contour of the horizontal cross-section of the anchor bolt nut 7 is larger than the diameter of the through hole, or a fixing gasket is provided on the side of the anchor bolt nut 7 close to the through hole, and the outer diameter of the fixing gasket is larger than the diameter of the through hole.

[0047] Optionally, when loosening the anchor bolt nut 7, the anchor bolt nut 7 may be adjusted by 2 to 3 threads to ensure that the seat ring 2 can move radially relative to the anchor bolt 6.

[0048] In some embodiments, the anchor bolts 6 are arranged in pairs, and there are 4 to 8 pairs of anchor bolts 6. When tightening or loosening multiple anchor bolt nuts 7 one by one, they are screwed one by one in a symmetrical pattern. By arranging the anchor bolts 6 in pairs, it is convenient to fix the seat ring 2, avoid an unbalanced connection when the anchor bolts 6 and the seat ring 2 are fixed, and ensure operational safety.

[0049] In some embodiments, in step S4, the fitting section 4 is divided into equal parts into Z petals with a length of L meters. The petals of the fitting section 4 are installed and welded in sequence, and then the annular seam between the fitting section 4 and the pressure steel pipe 1 is welded, and the last welded annular seam 5, that is, the closing seam between the fitting section 4 and the volute 3 is reserved without welding, so as to avoid stress concentration at the weld position and cracks at the weld position during welding, ensure the welding quality of the weld, and provide driving force for the position adjustment of the seat ring 2 and the volute 3.

[0050] In some embodiments, in step S5, when the welding annular seam 5 is closed and welded, additional measures are taken to monitor the displacement and deformation of the seat ring 2, and deformation monitoring is performed on relevant parts of the seat ring 2 until the installation is completed to avoid excessive displacement or deformation affecting the connection stability of the seat ring 2; the installation gap of the closed and closed welding annular seam 5 is controlled, and the installation gap range is 1 to 3 mm. The welding process formulated and provided by the turbine equipment manufacturer is adopted, and conventional manual hammering is used to assist in stress relief to further reduce stress concentration at the connection position of the joint 4; during the closing seam welding process, the distance and orientation between the X and Y marks on the upper and lower ring surfaces of the seat ring 2 and the X and Y reference lines of the unit are monitored, and at the same time, dial indicators are installed on the upper and lower ring parts of the seat ring 2 to monitor the deformation value of the seat ring 2, and the closing seam welding process is dynamically adjusted according to the monitored deformation value.

[0051] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0053] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0055] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0056] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for joint installation of embedded parts of a water turbine, characterized in that: The following steps are involved: S1: Install the penstock and pour the outer layer of reinforced concrete outside the penstock; S2: Cast the seat ring foundation and install and fix the seat ring; S3: Install the volute between the seat ring and the pressure steel pipe, and reserve installation space between the volute and the pressure steel pipe; S4: Install a joint between the volute and the pressure steel pipe, fully weld the pressure steel pipe and the joint, weld the joint to the volute, and reserve a welding annular seam at the connection position between the joint and the volute; S5: Release the fixation of the seat ring, so that the seat ring is in a free stress state, and weld the welding annular seam at the connection position between the joint and the volute to close; S6: After determining the installation elevation and horizontal deviation of the seat ring and making fine adjustments, re-fix and install the ring seat; S7: Pour the outer layer reinforced concrete at the seat ring position, the volute position, and the joint position between the volute and the pressure steel pipe, monitor the deformation of relevant parts, and dynamically adjust the concrete pouring plan until the overall pouring is completed.

2. The method for combined installation of embedded parts of a water turbine according to claim 1, characterized in that: In step S1, the penstock is installed in the lower flat section or the inclined section plus the lower flat section of the diversion tunnel of the hydropower station and is located on the upstream side of the turbine volute. After the penstock is installed in place, the outer casing concrete is poured and contact grouting is performed.

3. The method for combined installation of embedded parts of a water turbine according to claim 2, characterized in that: In step S1, the penstock includes a plurality of pipe sections, which need to be welded separately to complete the pre-processing of the penstock. When the penstock is transported to the water diversion tunnel of the plant for assembly, the penstock and the water diversion tunnel are subjected to circumferential welding and circumferential flaw detection, and the internal support of the penstock is installed.

4. The method for combined installation of embedded parts of a water turbine according to claim 1, characterized in that: In step S2, the seat ring is set to be multi-petal, and the multi-petal seat ring is assembled and welded into a whole, then hoisted into the machine pit for installation, and a seat ring installation platform is set up. The elevation, level and center dimensions are adjusted according to the requirements of the drawings, and radial displacement is reserved for the seat ring.

5. The method for combined installation of embedded parts of a water turbine according to claim 4, characterized in that: In step S2, pour the second phase concrete of the seat ring foundation anchor bolts, tighten the anchor bolt nuts after the concrete solidifies to fix the seat ring, and in step S5, loosen the multiple anchor bolt nuts one by one to release the fastening of the seat ring.

6. The method for combined installation of embedded parts of a water turbine according to claim 5, characterized in that: The anchor bolts are arranged in pairs, and when tightening or loosening a plurality of anchor bolt nuts one by one, they are screwed one by one in a symmetrical pattern.

7. The method for combined installation of embedded parts of a water turbine according to claim 1, characterized in that: In step S4, the joint section is divided into equal parts and cut into pieces, the joint section petals are installed and welded in sequence, the annular seam between the joint section and the pressure steel pipe is welded, and a welding annular seam is reserved between the joint section and the volute.

8. The method for combined installation of embedded parts of a water turbine according to claim 7, characterized in that: In step S5, when the welding annular seam is closed, a measure for monitoring the displacement and deformation of the seat ring is added, and deformation monitoring is performed on relevant parts of the seat ring until the installation is completed.

9. The method for combined installation of embedded parts of a water turbine according to claim 8, characterized in that: In step S5, the installation gap of the closed welded annular seam is controlled by using a welding process and supplemented by artificial hammering to eliminate stress.

10. The method for combined installation of embedded parts of a water turbine according to claim 8, characterized in that: In step S5, during the closing seam welding process, the distance and orientation between the X, Y marks on the upper and lower ring surfaces of the seat ring and the X, Y reference lines of the unit are monitored. At the same time, dial indicators are installed on the upper and lower ring parts of the seat ring to monitor the deformation value of the seat ring, and the closing seam welding process is dynamically adjusted according to the monitored deformation value.

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