Sound absorption and noise reduction device for intermediate frequency furnace

Abstract

The utility model discloses an intermediate frequency furnace sound absorption and noise reduction device which comprises a left clamping sleeve and a right clamping sleeve which are arranged in a half mode, and the left clamping sleeve and the right clamping sleeve are fixedly connected with an intermediate frequency furnace shell through a plurality of first fixing holes formed in the bottoms of the clamping sleeves and a plurality of second fixing holes formed in the side walls of the clamping sleeves respectively. The left clamping sleeve and the right clamping sleeve are both filled with superfine mineral fiber spraying cotton, and a plurality of sound absorption holes are formed in the inner walls of the clamping sleeves. A first heat dissipation hole and a second heat dissipation hole are reserved in the left clamping sleeve and the right clamping sleeve respectively, and the first heat dissipation hole and the second heat dissipation hole correspond to heat dissipation holes in a shell of the intermediate frequency furnace respectively. The device can absorb most noise generated by the intermediate frequency furnace from the source, and is low in cost, simple, practical, safe and environment-friendly.

Description

Technical Field

[0001] This utility model belongs to the field of pyrometallurgical technology, specifically relating to a sound-absorbing and noise-reducing device for a medium-frequency furnace. Background Technology

[0002] An intermediate frequency furnace is a power supply device that converts 50Hz AC power into intermediate frequency (300Hz to 1000Hz). It rectifies the three-phase AC power into DC power, then converts the DC power into an adjustable intermediate frequency current, which is supplied to the intermediate frequency alternating current flowing through the capacitor and induction coil. This generates high-density magnetic lines of force in the induction coil, cutting through the metal material inside and generating large eddy currents, thus heating the metal using electromagnetic induction. However, the intermediate frequency furnace produces noise due to both the excitation of the induction coil by the alternating electromagnetic force and the fact that the induction coil is a resonant sound generator. This creates a continuous and annoying hissing sound, which can silently damage the hearing, nervous system, cardiovascular system, digestive system, immune system, and endocrine system of workers, causing symptoms such as chest tightness, shortness of breath, palpitations, and discomfort in the precordial region. Improvements are urgently needed.

[0003] Currently, the industry generally adopts simple measures to control noise from medium-frequency furnaces, such as installing soundproof doors, laying sound-absorbing materials inside the factory, and requiring workers to wear earplugs. However, these methods do not address the root cause of the problem. The first two methods only reduce noise within the factory premises; noise from the operating tables increases rather than decreases due to the obstructed noise flow caused by the sealed factory. Wearing earplugs only temporarily blocks noise transmission, but it severely affects communication among workers, which is detrimental to quality and safety. Utility Model Content

[0004] In view of the problems existing in the above-mentioned background technology, this utility model discloses a simple and practical sound absorption and noise reduction device for medium frequency furnaces, which absorbs most of the noise generated by medium frequency furnaces at the source. It is low in cost, simple and practical, safe and environmentally friendly.

[0005] Therefore, the present invention adopts the following technical solution:

[0006] A sound-absorbing and noise-reducing device for an intermediate frequency furnace includes a left jacket and a right jacket arranged in two halves. The left jacket and the right jacket are respectively fixedly connected to the outer shell of the intermediate frequency furnace through several first fixing holes provided at the bottom of the jacket and several second fixing holes provided on the side wall of the jacket. The interior of the left jacket and the right jacket are filled with ultra-fine mineral fiber sprayed cotton, and multiple sound-absorbing holes are opened on the inner wall of the jacket. The left jacket and the right jacket are also respectively reserved with a first heat dissipation hole and a second heat dissipation hole, which correspond to the heat dissipation holes on the outer shell of the intermediate frequency furnace.

[0007] Compared with the prior art, the present invention has the following beneficial effects:

[0008] During production, the noise generated by the induction furnace coil passes through several furnace shell holes and acoustic holes in the inner walls of the left and right jackets, transmitting to the left and right jackets. These jackets are filled with ultra-fine mineral fiber sprayed cotton. Most of the noise is absorbed within this cotton, rather than diffused into the factory, effectively cutting off the propagation path at its origin. Measurements show that the continuous hissing noise in the space where one induction furnace is installed reaches at least 100 dB. The sound absorption and noise reduction effect primarily depends on the thickness of the inorganic fiber sprayed cotton within the jackets. Actual testing after installation showed that filling the factory with 100 mm of ultra-fine mineral fiber sprayed cotton can reduce the noise generated by one induction furnace from 100 dB to below 55 dB. In practical applications, the thickness of the inorganic fiber sprayed cotton can be adjusted according to the noise level at the site. According to national noise classification standards, 100 dB of noise at the site is already considered environmental pollution. Long-term exposure to noise levels above 90 dB can seriously affect hearing and lead to other diseases. After installing sound-absorbing and noise-reducing devices, the noise level can be reduced to at least 55 decibels, which meets the national noise standards for industrial parks, namely 65 decibels during the day and 55 decibels at night. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of this utility model.

[0010] Figure 2 This is a diagram showing the usage state of this utility model.

[0011] In the figure, 1-left jacket, 2-right jacket, 3-first fixing hole, 4-second fixing hole, 5-sound absorption hole, 6-first heat dissipation hole, 7-second heat dissipation hole, 8-ultra-fine mineral fiber sprayed cotton layer, 9-hole in the outer shell of the medium frequency furnace, 10-fixing bolt, 11-rotating shaft of the medium frequency furnace, 12-coil of the medium frequency furnace, and 13-heat dissipation hole in the outer shell of the medium frequency furnace. Detailed Implementation

[0012] The present invention will be further explained below with reference to the accompanying drawings.

[0013] like Figure 1As shown, a sound-absorbing and noise-reducing device for an intermediate frequency furnace consists of two symmetrical left jackets 1 and right jackets 2. The shells of the jackets are welded from 310S stainless steel plates and filled with ultra-fine mineral fiber sprayed cotton. The left and right jackets are connected to the outer shell of the intermediate frequency furnace through several first fixing holes 3 on the jacket base plate and several second fixing holes 4 on the jacket sidewalls. The radius of the inner wall of the jacket is equal to the radius of the outer shell of the intermediate frequency furnace, and the inner wall of the jacket fits tightly against the outer shell of the intermediate frequency furnace. The jackets act like an "outer garment" for the intermediate frequency furnace, wrapping around it. The left and right jackets have first heat dissipation holes 6 and second heat dissipation holes 7, respectively. The size of the heat dissipation holes is similar to the heat dissipation holes 13 on the outer shell of the intermediate frequency furnace, which is intended to prevent the temperature of the outer shell and jackets from becoming too high. Several sound-absorbing holes 5 are provided on the inner walls of the left and right jackets, which are used to transmit the noise generated by the intermediate frequency furnace to the ultra-fine mineral fiber sprayed cotton through the sound holes, thereby absorbing and reducing noise.

[0014] The most crucial aspect of this device is the selection of the sound-absorbing material for the jacket filling. Inorganic fiber sprayed cotton is the preferred choice because it meets three key requirements for sound absorption: a large number of internal voids; and the voids extending deep into the material and being interconnected. Ultra-fine mineral fiber sprayed cotton contains numerous interconnected micropores and cavities, allowing noise to enter the material through these voids. This causes the air molecules within the voids to vibrate. Due to the viscous resistance of the air and the friction between the air molecules and the void walls, sound energy is converted into frictional heat energy, resulting in sound absorption. It has excellent sound absorption effects for mid-frequency sounds at 1000Hz. Ultra-fine mineral fiber sprayed cotton has a noise reduction coefficient (30mm) NRC≥0.80, sound insulation (30mm)≥20dB(A), thermal conductivity ≤0.04w / m℃, and temperature resistance of 600-800℃, making it an ideal sound-absorbing and noise-reducing material. This cotton is A1 non-combustible grade, lightweight, odorless, and has good weather resistance; it is also a new type of safe and environmentally friendly material.

[0015] The second important aspect of this device is the selection of the jacket shell material. The jacket shell should ideally be made of heat-resistant stainless steel, typically 310S stainless steel plate welded together. 310S belongs to the 25Cr-20Ni series of high-alloy stainless steel, possessing excellent high-temperature oxidation resistance, a maximum temperature of 1200℃, and a continuous operating temperature of 1150℃. It is suitable for manufacturing various furnace components and is a commonly used furnace material. Generally, due to the radiant heat from the coils, the temperature of the medium-frequency furnace shell and jacket can reach 300-350℃. Using 310S heat-resistant stainless steel plate for the jacket shell meets the temperature requirements of the process and also has an aesthetically pleasing, simple, and elegant appearance.

[0016] like Figure 2As shown, during the production process, the noise generated by the intermediate frequency furnace coil passes sequentially through several holes 9 in the outer shell of the intermediate frequency furnace and sound-absorbing holes 5 on the inner walls of the left and right jackets, and is transmitted to the left jacket 1 and right jacket 2. The jackets are filled with ultra-fine mineral fiber sprayed cotton. Most of the noise is absorbed in the ultra-fine mineral fiber sprayed cotton, rather than diffused into the factory, thus cutting off the propagation path at the source of the noise. It has been measured that the continuous "hissing" noise in the space where an intermediate frequency furnace is installed reaches at least 100 dB. The sound absorption and noise reduction effect mainly depends on the thickness of the inorganic fiber sprayed cotton in the jacket. After actual testing after installation, filling with 100 mm of ultra-fine mineral fiber sprayed cotton can reduce the noise in the factory generated by an intermediate frequency furnace from 100 dB to below 55 dB. In practical applications, the thickness of the inorganic fiber sprayed cotton can be adjusted according to the noise level on site. According to the national noise classification, 100 dB of noise on site is already considered environmental pollution. Long-term work in a noise environment above 90 dB will seriously affect hearing and lead to other diseases. After installing sound-absorbing and noise-reducing devices, the noise level can be reduced to at least 55 decibels, which meets the national noise standards for industrial parks, namely 65 decibels during the day and 55 decibels at night.

[0017] In summary, this medium-frequency furnace sound absorption and noise reduction device is simple, practical, safe, environmentally friendly, and easy to manufacture, making it a practical patented technology worthy of promotion.

Claims

1. A sound-absorbing and noise-reducing device for a medium-frequency furnace, characterized in that, It includes a left jacket (1) and a right jacket (2) that are set in two halves. Both the left jacket (1) and the right jacket (2) are fixedly connected to the outer shell of the medium frequency furnace through several first fixing holes (3) set at the bottom of the jacket and several second fixing holes (4) set on the side wall of the jacket. The interior of both the left jacket (1) and the right jacket (2) is filled with ultra-fine mineral fiber sprayed cotton, and multiple sound-absorbing holes (5) are opened on the inner wall of the jacket. The left jacket (1) and the right jacket (2) are also reserved with a first heat dissipation hole (6) and a second heat dissipation hole (7), respectively. The first heat dissipation hole (6) and the second heat dissipation hole (7) correspond to the heat dissipation holes on the outer shell of the medium frequency furnace.

2. The sound absorption and noise reduction device for a medium-frequency furnace as described in claim 1, characterized in that, The dimensions of the first heat dissipation hole (6) and the second heat dissipation hole (7) are comparable to the dimensions of the heat dissipation holes on the outer shell of the medium frequency furnace.

Images