Water pump water turbine water wheel chamber combined type protection noise reduction device

Abstract

The utility model provides a kind of water pump water turbine water cart room combined type protection noise reduction device, it is related to water conservancy power generation equipment technical field, including support frame, inspection pedal, protective rail, combined type protection sound insulation heat dissipation door, protective door, machine cover sound absorption mechanism and top cover sound absorption mechanism.Combined type protection sound insulation heat dissipation door includes sound lock fixed section, sound lock passage door and ventilation sound reduction system, adopts double sound insulation door structure, door spacing is 1.2 meters.Machine cover sound absorption mechanism and top cover sound absorption mechanism all include sound insulation layer, sound absorption layer and vacuum cavity, vacuum cavity adopts gradient vacuum design, outer layer, middle layer, inner layer cavity vacuum degree is 0.1Pa, 1Pa, 10Pa respectively.The utility model effectively solves the technical problems, such as low frequency noise control difficulty, heat accumulation is serious, maintenance is inconvenient.

Description

Technical Field

[0001] This utility model relates to the field of hydropower equipment technology, specifically to a combined protection and noise reduction device for water pump, turbine, and waterwheel chamber. Background Technology

[0002] Pumped storage power stations, as important peak-shaving, frequency regulation, and energy storage facilities in the power system, generate significant noise pollution during the operation of their core equipment, the pump-turbine. Pump-turbines are mainly classified into mixed-flow, diagonal-flow, and through-flow types, with mixed-flow pump-turbines being the most widely used in medium and large-sized pumped storage power stations due to their wide applicable head range and high efficiency. However, because pumped storage units have high heads, large outputs, and frequent operating condition changes, the noise pollution generated during unit operation is becoming increasingly prominent, seriously affecting the health and working environment of power station workers.

[0003] Pumped-storage power station generators are typically installed in large, enclosed underground tunnels within mountains. These tunnels are spacious and their surfaces are mostly made of concrete and cement mortar, materials with low sound absorption coefficients. In this unique acoustic environment, the noise generated by the generators undergoes multiple reflections within the tunnel, resulting in extremely slow sound attenuation and further exacerbating noise pollution. In particular, the 80-200Hz low-frequency noise generated by the turbines has strong penetrating power and poses a greater threat to human health. Power station workers exposed to prolonged high-noise environments are prone to occupational diseases such as hearing loss, tinnitus, and neurasthenia.

[0004] Currently, the main technical solutions for noise control in water pumps and turbines employ passive noise reduction measures. Traditional solutions often use in-ear earplugs for personal protection, but prolonged wear can cause discomfort for workers, and simple sound insulation materials can only reduce some high-frequency noise, offering unsatisfactory sound insulation for the low-frequency noise generated by the turbine generator set. Existing noise reduction devices have significant technical shortcomings: First, their low-frequency noise attenuation efficiency is extremely low; traditional sound insulation materials such as polyester fiberboard typically reduce noise in the 80-200Hz low-frequency range by less than 3dB, far from meeting practical needs. Second, enclosed sound insulation devices generally suffer from heat accumulation problems, with internal temperatures reaching 55-65℃, severely impacting equipment lifespan; statistics show that the failure rate increases by 15% for every 10℃ increase in equipment temperature. Furthermore, existing devices have significant deficiencies in maintenance access design, with an average maintenance time of 3.5 hours per visit, significantly higher than the 1.2 hours per visit for open structures, severely affecting equipment maintenance efficiency.

[0005] Patent document CN211397762U discloses a noise reduction device for a hydro-generator. This device installs the generator body inside a protective cover, utilizing sound-absorbing and sound-insulating layers to achieve noise reduction. However, this technical solution has significant drawbacks: firstly, the lack of an effective ventilation and heat dissipation system leads to an 8-12°C increase in temperature inside the cover, preventing the effective dissipation of heat generated by the generator unit and hindering long-term stable operation; secondly, the device lacks a dedicated maintenance access structure and walking platform, making it inconvenient for personnel to inspect and maintain the equipment internally, severely impacting the convenience and safety of equipment maintenance.

[0006] Patent document CN216198606U discloses a fully enclosed sound-absorbing and noise-reducing device for a water pump turbine waterwheel chamber, including a floor ladder walking plate, a floor ladder cover plate, a floor ladder sound-absorbing mechanism, and a pit wall sound-absorbing mechanism. This device places all components inside the waterwheel chamber, using a ring-shaped hollow box structure to house the sound-absorbing mechanism and achieve noise reduction. While this solution addresses the maintenance access issue to some extent, it still relies on traditional sound-absorbing materials and a single passive sound insulation method, resulting in limited control over low-frequency noise. Furthermore, it lacks effective heat dissipation, failing to address the problem of heat accumulation within the enclosed space. Utility Model Content

[0007] The purpose of this utility model is to provide a combined protection and noise reduction device for pump-turbine water turbine chambers, which integrates noise reduction, heat dissipation and protection functions. It can solve the key technical problems in the existing technology of pump-turbine noise control in pump-storage power stations, such as low efficiency of low-frequency noise attenuation, serious heat accumulation and inconvenient maintenance.

[0008] To achieve the above objectives, this utility model employs the following technical solution:

[0009] A combined protective noise reduction device for a water pump turbine waterwheel chamber includes: a support frame, an inspection tread, a guardrail, a combined protective soundproof heat dissipation door, a protective door, a hood sound absorption mechanism, and a top cover sound absorption mechanism;

[0010] The support frame is provided below the inspection pedal, and the guardrail is provided above the inspection pedal;

[0011] The combined protective soundproof and heat dissipation door includes a sound gate fixed section, a sound gate passage door and a ventilation and silencing system. The sound gate fixed section and the sound gate passage door form a closed soundproof body. The ventilation and silencing system includes sound-absorbing louvers and a fan.

[0012] The outer ends of the hood sound-absorbing mechanism and the top cover sound-absorbing mechanism are integrated. The hood sound-absorbing mechanism includes a hood, a sound insulation layer, a sound-absorbing layer, and a vacuum cavity. The top cover sound-absorbing mechanism includes a metal shell, a sound insulation layer, a sound-absorbing layer, and a vacuum cavity.

[0013] Furthermore, the vacuum cavity adopts a gradient vacuum design, including an outer cavity, a middle cavity, and an inner cavity, with the vacuum levels of the outer cavity, middle cavity, and inner cavity increasing sequentially.

[0014] Furthermore: the vacuum degree of the outer cavity is 0.05~0.2Pa, the vacuum degree of the middle cavity is 0.5~5Pa, and the vacuum degree of the inner cavity is 5~50Pa.

[0015] Furthermore, the sound-absorbing layer adopts a gradient sound-absorbing structure, including a centrifugal glass wool layer, a gradient density fiber layer, a micro-perforated plate layer, and a back cavity layer.

[0016] Furthermore, the combined protective soundproof heat dissipation door adopts a double soundproof door structure, with a distance of 1.2 meters between the two soundproof doors.

[0017] Furthermore, a magnetic fluid sealing strip is provided at the bottom of the protective door, which is used to achieve adaptive compensation of the door gap.

[0018] Furthermore, the sound insulation layer adopts a composite sound insulation structure, including a constraint damping layer, a sound insulation felt, and an elastic isolation layer.

[0019] Furthermore, the vacuum chamber is equipped with a vacuum maintenance system, which includes a molecular pump and a sputtering ion pump.

[0020] Furthermore: the inspection pedal adopts an aluminum alloy honeycomb panel structure, the guardrail adopts a stainless steel pipe structure, and a kick plate is provided at the bottom of the guardrail.

[0021] Furthermore, it also includes a ladder for accessing the inspection pedal.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] I. This utility model effectively solves the technical problem of low attenuation efficiency of low-frequency noise by using gradient vacuum cavity technology. The gradient vacuum cavity adopts a three-level vacuum design with an outer layer of 0.05~0.2Pa, a middle layer of 0.5~5Pa, and an inner layer of 5~50Pa. The sound wave energy is gradually attenuated during propagation, overcoming the technical defect of traditional sound insulation materials in controlling low-frequency noise of 80-200Hz.

[0024] II. This utility model effectively solves the technical problem of severe heat accumulation in enclosed soundproof devices through a combined protective soundproof and heat-dissipating door ventilation and silencing system. The fan, in conjunction with the sound-absorbing louvers, achieves forced ventilation and heat dissipation, avoiding the problem of excessively high internal temperature affecting equipment lifespan in existing technologies.

[0025] Third, this utility model effectively solves the technical problem of maintenance channel design defects through the reasonable design of maintenance channels such as inspection pedals, guardrails, and ladders, as well as the detachable structure of the combined protective door, which not only ensures the sound insulation effect but also significantly improves the convenience and safety of equipment maintenance.

[0026] Fourth, this utility model achieves comprehensive control of noise in different frequency bands through the combination of gradient sound-absorbing layer structure and double soundproof door sound gate design, especially the effective control of low-frequency noise of water turbines, providing a better working environment for power station operators. Attached Figure Description

[0027] Figure 1 A half-sectional view of a combined protection and noise reduction device for a water pump, water turbine, and waterwheel chamber provided by this utility model;

[0028] Figure 2 for Figure 1 A half-sectional view of the utility model in the vertical direction;

[0029] Figure 3 for Figure 1 and Figure 2 Plan view of AA;

[0030] Figure 4 for Figure 1 and Figure 2 BB floor plan;

[0031] Figure 5 for Figure 1 and Figure 2 Detailed map of area A in the middle;

[0032] Figure 6 for Figure 1 and Figure 2 Detailed map of area B in central China;

[0033] In the diagram: 1. High-strength, large-volume reinforced concrete; 1-1. Machine pier; 1-2. Drainage ditch; 2. Water pump and turbine; 2-1. Waterwheel room; 2-2. Upper frame; 3. Thick reinforced concrete slab; 3-1. Finishing layer; 4. Support frame; 5. Inspection board; 6. Guardrail; 7. Ladder; 8. Combined protective soundproof and heat-dissipating door; 8-1. Soundlock fixed section; 802. Sound-absorbing louvers; 803. Soundproofing channel; 804. Soundlock access door; 805. 9. Fan; 10. Protective door; 11. Door leaf; 12. Door frame; 13. Magnetic fluid sealing strip; 14. Machine cover sound absorption mechanism; 15. Machine cover; 16. Sound insulation layer; 17. Sound absorption layer; 18. Inner mounting layer; 19. Vacuum chamber; 10. Top cover sound absorption mechanism; 11. Metal shell; 11. Sound insulation layer; 11. Sound absorption layer; 12. Inner mounting layer; 13. Vacuum chamber; 14. Steel frame. Detailed Implementation

[0034] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0035] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] like Figure 1-6 As shown, the combined protection and noise reduction device for the pump-turbine waterwheel chamber provided by this utility model includes a support frame 4, an inspection pedal 5, a guardrail 6, a combined protective soundproof and heat dissipation door 8, a protective door 9, a hood sound absorption mechanism 10, and a top cover sound absorption mechanism 11. The entire device is installed inside the waterwheel chamber 2-1 of the pump-turbine 2 in a pumped storage power station, providing comprehensive noise protection and heat dissipation protection for the pump-turbine.

[0037] Specifically, the inspection platform 5 adopts an aluminum alloy honeycomb panel structure with a thickness of 30 mm. Its load standard is no less than 500 kg / m², and its deflection is controlled within one-three-hundredth of the support span. The honeycomb panel core layer density is 0.8 g / cm³, and the surface is anodized with a film thickness of no less than 15 micrometers. Anti-slip toothed strips are installed on the edges with a height of 5 mm to ensure the safety of personnel walking on it. A support frame 4 is installed below the inspection platform 5. The support frame 4 adopts a Q355B steel truss structure with a lateral span not exceeding 2 meters and a longitudinal spacing not exceeding 1.5 meters. To further improve seismic performance, the support frame 4 is equipped with a viscous damper with a damping coefficient of 1500 N / s / m. Seismic bracing is used at the connection nodes to effectively prevent deformation of the inspection platform 5.

[0038] A guardrail 6 is installed above the inspection platform 5. The guardrail 6 is made of 304 stainless steel tubing with a diameter of 50 mm, a wall thickness of 3 mm, and a height of 1.2 meters. The spacing between the posts does not exceed 1.5 meters. A kickboard is installed at the bottom of the guardrail 6. The kickboard is made of 2 mm thick galvanized steel plate and is at least 150 mm high to ensure the safety of personnel. The lower space is accessed via a ladder 7, which is made of non-slip aluminum-magnesium alloy with a width of at least 400 mm and a load-bearing capacity of at least 150 kg.

[0039] The combined protective soundproof and heat dissipation door 8 is an important component of this utility model. It adopts a double soundproof door structure, including a soundlock fixing section 8-1, a soundlock passage door 804, and a ventilation and silencing system. The soundlock fixing section 8-1 and the soundlock passage door 804 form a closed soundproof body, which is fixed to the passage wall. The distance between the two soundproof doors is 1.2 meters, which is the half-wavelength distance of the sound wave designed for the dominant frequency of 125 Hz noise, and can form an effective soundlock effect. On the right side of the soundproof door, there is a 1.0-meter-wide soundproof passage door for easy access for personnel and equipment. The door and the door frame adopt double-step sound insulation and are equipped with sealing strips, which makes the door easy to open and close without affecting the sound insulation performance.

[0040] The ventilation and noise reduction system includes sound-absorbing louvers 802 and a fan 805. The sound-absorbing louvers 802 employ a three-dimensional tapered flow channel design with a gradient change in blade spacing: 30 mm at the inlet and 15 mm at the outlet. The blade inclination angle is 15 degrees, the inlet velocity does not exceed 2 m / s, the outlet diffusion angle is 8 degrees, and the pressure drop loss is less than 50 Pascals. The fan 805 is an EC centrifugal low-noise type with an air volume of 800 cubic meters per hour, an error range of ±5%, and an operating noise level not exceeding 45 decibels. To ensure ventilation for personnel during maintenance in the water turbine room, sound-absorbing louvers 802 are installed on the sound damper, and an axial flow fan with enhanced ventilation is installed inside the sound damper. The sound damper is designed as a modular unit and is detachable to meet the needs of major overhauls.

[0041] The protective door 9 consists of a door frame 9-2 and a door leaf 9-1. The door leaf 9-1 is made of 1.5 mm thick high-quality cold-rolled steel plate, cold-formed, and filled with sound-absorbing, damping, and sound-insulating materials according to the sound insulation level. The door frame 9-2 is also made of 1.5 mm thick high-quality cold-rolled steel plate, cold-formed, and is a modular assembly type that does not require pre-embedding. The bottom of the protective door 9 is equipped with a magnetic fluid sealing strip 9-3, which contains iron oxide nanoparticles with a particle size of less than 50 nanometers. The sealing pressure is adjusted by an electromagnetic coil, with a pressure range of 0.1 to 0.5 MPa, to achieve adaptive compensation of door gaps, with a compensation range of 0.5 to 3 mm.

[0042] The outer ends of the hood sound-absorbing mechanism 10 and the top hood sound-absorbing mechanism 11 are integrated to form a complete enclosure of the water pump turbine 2. The hood sound-absorbing mechanism 10 includes a hood 10-1, a sound insulation layer 10-2, a sound-absorbing layer 10-3, and a vacuum chamber 10-5. The hood 10-1 is made of aluminum alloy with a yield strength of not less than 240 MPa, a thickness of 8 mm, and a surface treated with sandblasting and anodizing, with a roughness of not more than 3.2 micrometers. The hood 10-1 adopts a biomimetic streamlined curved surface design with a radius of curvature of not less than 500 mm, effectively eliminating standing wave effects and reducing turbulent noise.

[0043] Sound insulation layer 10-2 employs a composite sound insulation structure, including a restrained damping layer, sound insulation felt, and an elastic isolation layer. The restrained damping layer is made of butyl rubber, 2 mm thick, with a loss factor of 0.35. The sound insulation felt is made of lead fiber composite material, 10 mm thick, with a surface density of 8 kg / m² and a lead content of 60%. The elastic isolation layer is made of polyurethane foam, 20 mm thick, with a density of 80 kg / m³ and a porosity of 85%. The weighted sound insulation of this three-layer composite structure reaches 42 dB.

[0044] The sound-absorbing layer 10-3 employs a gradient sound-absorbing structure, comprising a centrifugal glass wool layer, a gradient-density fiber layer, a micro-perforated plate layer, and a back cavity layer. The centrifugal glass wool layer uses 32 kg / m³ material, is 50 mm thick, and has a noise reduction coefficient of 0.95. The gradient-density fiber layer uses gradient-density basalt fiber with a density of 40 kg / m³ and a thickness of 30 mm. The micro-perforated plate layer uses micro-perforated aluminum plates with a pore size of 0.8 mm, a perforation rate of 32%, and a plate thickness of 1.2 mm. The back cavity layer is a Helmholtz resonator with a depth of 80 mm and a volume ratio of 1:1.5. This four-layer gradient structure achieves a sound absorption coefficient of 0.82 at 125 Hz.

[0045] The core innovation of this invention is the vacuum chamber 10-5, which employs a gradient vacuum design, comprising an outer cavity, a middle cavity, and an inner cavity. The outer cavity has a vacuum level of 0.1 Pa and a thickness of 50 mm; the middle cavity has a vacuum level of 1 Pa and a thickness of 30 mm; and the inner cavity has a vacuum level of 10 Pa and a thickness of 20 mm. Vacuum chamber 10-5 utilizes vacuum brazing encapsulation technology, achieving a helium leak detection rate of less than or equal to 1 x 10⁻⁹ Pascals per second. Vacuum chamber 10-5 is equipped with a vacuum maintenance system, including a molecular pump and a sputtering ion pump. The molecular pump has a pumping speed of 300 liters per second, and the sputtering ion pump has an ultimate vacuum of 5 x 10⁻⁷ Pascals, ensuring long-term stable operation of the vacuum chamber.

[0046] The top-mounted sound-absorbing mechanism 11 includes a metal shell 11-1, a sound insulation layer 11-2, a sound-absorbing layer 11-3, and a vacuum chamber 11-5. The metal shell 11-1 is made of SUS304 stainless steel, 6 mm thick, and coated with a fluorocarbon coating, providing over 3000 hours of salt spray resistance. The metal shell 11-1 employs a two-way curved corrugated plate structure with a wave height of 15 mm and a wavelength of 60 mm, increasing rigidity by 30% compared to a flat plate structure. The top-mounted sound-absorbing mechanism 11 also includes a steel frame 11-6, a truss structure using Q420B H-beams with a cross-section of 200 mm x 200 mm x 8 mm x 12 mm. The joints are connected using friction-type high-strength bolts with a preload of 310 kN, achieving a seismic fortification intensity of level 8.

[0047] The sound insulation layer 11-2 of the top-mounted sound-absorbing mechanism 11 adopts a double-layer heterogeneous structure. The outer layer is a calcium silicate board with a thickness of 10 mm, a density of 1.2 g / cm³, and a thermal conductivity of 0.06 W / m Kelvin. The inner layer is a nanoporous aerogel felt with a thickness of 10 mm, a porosity of 98%, and a specific surface area of ​​800 m² / g. The sound-absorbing layer 11-3 also adopts a four-layer gradient structure, but the parameters are adjusted to suit the characteristics of top mounting. The design of the vacuum chamber 11-5 is the same as that of the machine cover sound-absorbing mechanism 10, also employing a gradient vacuum design and a vacuum maintenance system.

[0048] In terms of construction and installation, the sound-absorbing layer adopts a layered filling technology. The bottom layer is 32 kg / m³ glass wool, followed by gradient density sound-absorbing cotton, micro-perforated membrane, and back cavity layer. The glass wool filling compression rate is controlled at 10% to 15%, and a negative pressure suction positioning process is used to ensure construction quality. The vacuum cavity is manufactured using thermo-pressurization sealing technology to ensure sealing performance.

[0049] To prevent corrosion, all metal components undergo a three-layer protective treatment, including an 80-micron epoxy zinc-rich primer, a 120-micron micaceous iron oxide intermediate coat, and a 60-micron fluorocarbon topcoat, ensuring long-term stable operation of the equipment in the humid underground plant environment.

[0050] During unit maintenance, the detachable and modular protective door and soundproof lock fixed section are removed from the protective cover using a hydraulic lifting device. The load-bearing capacity is no less than 2 tons, and the entire process takes no more than 45 minutes, which greatly improves maintenance efficiency.

[0051] By implementing the above-mentioned technical solution, this utility model effectively solves the technical problems of low-frequency noise control, heat accumulation, and inconvenient maintenance in the operation of pump-turbines in pumped storage power stations, providing a reliable guarantee for the safe and efficient operation of the power station.

[0052] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent transformations or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. A combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber, characterized in that, include: Support frame, inspection pedal, guardrail, combined protective soundproof heat dissipation door, protective door, machine cover sound absorption mechanism and top cover sound absorption mechanism; The support frame is provided below the inspection pedal, and the guardrail is provided above the inspection pedal; The combined protective soundproof and heat dissipation door includes a sound gate fixed section, a sound gate passage door and a ventilation and silencing system. The sound gate fixed section and the sound gate passage door form a closed soundproof body. The ventilation and silencing system includes sound-absorbing louvers and a fan. The outer ends of the hood sound-absorbing mechanism and the top cover sound-absorbing mechanism are integrated. The hood sound-absorbing mechanism includes a hood, a sound insulation layer, a sound-absorbing layer, and a vacuum cavity. The top cover sound-absorbing mechanism includes a metal shell, a sound insulation layer, a sound-absorbing layer, and a vacuum cavity.

2. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The vacuum cavity adopts a gradient vacuum design, including an outer cavity, a middle cavity, and an inner cavity, with the vacuum levels of the outer cavity, middle cavity, and inner cavity increasing sequentially.

3. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 2, characterized in that, The vacuum level of the outer cavity is 0.05~0.2 Pa, the vacuum level of the middle cavity is 0.5~5 Pa, and the vacuum level of the inner cavity is 5~50 Pa.

4. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The sound-absorbing layer adopts a gradient sound-absorbing structure, including a centrifugal glass wool layer, a gradient density fiber layer, a micro-perforated plate layer, and a back cavity layer.

5. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The combined protective soundproof heat dissipation door adopts a double soundproof door structure, with a distance of 1.2 meters between the two soundproof doors.

6. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The bottom of the protective door is equipped with a magnetic fluid sealing strip, which is used to achieve adaptive compensation of the door gap.

7. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The sound insulation layer adopts a composite sound insulation structure, including a constraint damping layer, a sound insulation felt, and an elastic isolation layer.

8. The combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The vacuum chamber is equipped with a vacuum maintenance system, which includes a molecular pump and a sputtering ion pump.

9. A combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, The inspection pedal is made of aluminum alloy honeycomb panel structure, the guardrail is made of stainless steel pipe structure, and the bottom of the guardrail is equipped with a kick plate.

10. A combined protection and noise reduction device for a water pump, turbine, and waterwheel chamber according to claim 1, characterized in that, It also includes a ladder for accessing the inspection pedal.

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