Sealing piece for efficient sealing of inner floating disc and manufacturing method of sealing piece

Abstract

The invention relates to a sealing brush and a manufacturing method, in particular to a sealing piece for efficient sealing of an inner floating disc and a manufacturing method of the sealing piece, and solves the problems that a sealing structure arranged between an existing inner floating disc and a tank wall cannot meet the requirements for low emission of VOCs and efficient sealing, and the service life is short. The sealing piece for efficient sealing of the inner floating disc comprises a brush body, a brush handle, an upward guide part, N oil scraping brushes, M sealing brushes and a downward guide part. The ascending guide part is used for guiding the inner floating disc in the oil tank in the ascending process. The descending guide part is used for guiding the descending process of the inner floating disc in the oil tank; the oil scraping brush is in transition fit with the tank wall of the oil tank and is used for scraping and gathering residual oil on the tank wall of the oil tank in the descending process of the inner floating disc in the oil tank; the sealing brush is in interference fit with the tank wall of the oil tank and is used for being in interference contact with the tank wall of the oil tank in the running or static process of the inner floating disc in the oil tank, so that emission of volatile organic compounds is reduced. According to the manufacturing method, the service life of the product can reach 18 years.

Description

Technical Field

[0001] The invention relates to a sealing brush and a manufacturing method thereof, in particular to a sealing element for efficient sealing of an inner floating disc and a manufacturing method thereof. Background Art

[0002] To reduce volatilization and loss of stored oil within oil tanks, internal floats are typically installed. These floats rise and fall as the liquid surface within the tank changes due to changes in buoyancy, remaining above the surface of the stored oil. To prevent oil from leaking or seeping through the gap between the float and the tank wall, a seal is typically installed between the float and the tank wall, further minimizing oil loss.

[0003] With the increasing demand for environmental protection, the emission of volatile organic compounds (VOCs) is becoming increasingly stringent. Traditional internal float sealing structures, such as mechanical, liquid-filled bladder, air-filled bladder, sponge bladder, and scraper-type sealing structures, are no longer able to meet these low VOC emission requirements, and their service life is also short. To meet these low VOC emission requirements and improve the sealing efficiency and service life of the sealing structure, it is necessary to optimize the existing internal float sealing structure. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that the sealing structure provided between the existing inner floating plate and the tank wall is difficult to meet the requirements of low VOCs emission and high efficiency sealing, and has a short service life, and to provide a seal for high efficiency sealing of the inner floating plate and a manufacturing method thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A seal for efficiently sealing an inner floating plate, disposed between the inner floating plate and the tank wall and connected to the outer edge of the inner floating plate. The seal comprises a brush body, a brush handle connected to the side of the brush body near the inner floating plate, an upward guide portion, N scraping brushes, M sealing brushes, and a downward guide portion, disposed in order from top to bottom along the axial direction of the tank near the tank wall; N ≥ 1, M ≥ 1; the brush handle, upward guide portion, N scraping brushes, M sealing brushes, downward guide portion, and brush body are integrally formed, all made of rubber.

[0007] The inner side of the brush handle is used to connect with the inner float;

[0008] The upward guide portion is used to guide the inner floating plate during its upward movement in the oil tank. The angle between its outer side wall and the horizontal plane is the first guide angle, and the value range of the first guide angle is 40° to 65°.

[0009] The downward guiding part is used for guiding the inner floating roof during its descent in the oil tank. The angle between its outer sidewall and the horizontal plane is the second guiding angle, and the value range of the second guiding angle is 20° to 35°;

[0010] The outer edge size of the oil scraping brush is set according to the following rules: the outer edge of the oil scraping brush has an interference fit with the tank wall of the oil tank, and is used for scraping and gathering the residual oil on the tank wall of the oil tank during the descent of the inner floating roof in the oil tank;

[0011] The outer edge size of the sealing brush is set according to the following rules: the outer edge of the sealing brush has an interference fit with the tank wall of the oil tank, and is used for making an interference contact with the tank wall of the oil tank during the operation or still state of the inner floating roof in the oil tank, so as to reduce the emission of volatile organic compounds;

[0012] The upward guiding part is smoothly connected to the sidewall of the uppermost one of the N oil scraping brushes; the downward guiding part is smoothly connected to the sidewall of the lowermost one of the M sealing brushes.

[0013] Furthermore, the transition amount between the outer edges of the N oil scraping brushes and the tank wall of the oil tank is equal or gradually changes from top to bottom; the interference amount between the M sealing brushes and the tank wall of the oil tank is equal or gradually changes from top to bottom.

[0014] Furthermore, the value range of the first guiding angle is 45° to 60°; the value range of the second guiding angle is 22.5° to 30°; the transition amount between the outer edge of the oil scraping brush and the tank wall of the oil tank is 0 to 0.1; the interference amount between the outer edge of the sealing brush and the tank wall of the oil tank is 0.5 to 1.5 mm; the value of N is 2.

[0015] Furthermore, the brush handle is a U-shaped structure with an opening facing the brush body. The U-shaped bottom is used for connecting to the inner floating roof, and any one sidewall of the U-shaped structure is connected to the brush body; the brush handle, the upward guiding part, the oil scraping brush, the sealing brush, and the downward guiding part are an integral ring-shaped structure.

[0016] Furthermore, the length of the brush teeth of the oil scraping brush is 7 to 8 mm, the angle between the upper sidewall and the lower sidewall of the inclination angle of the brush teeth is 20° to 25°, the top is arc-shaped transition, the root width of the brush teeth is 4 to 5 mm, and the spacing between adjacent brush teeth is 6 to 7 mm; the length of the brush teeth of the sealing brush is 7 to 8 mm, the angle between the upper sidewall and the lower sidewall of the inclination angle of the brush teeth is 20° to 25°, the top is arc-shaped transition, the root width of the brush teeth is 4 to 5 mm, and the spacing between adjacent brush teeth is 6 to 7 mm; the brush tooth spacing between the lowermost one of the N oil scraping brushes and the uppermost one of the M sealing brushes is 6 to 7 mm.

[0017] Meanwhile, the present invention also provides a manufacturing method for the seal for the efficient sealing of the above-mentioned inner floating roof, which is characterized in that it includes the following steps:

[0018] S1. Weigh the required rubber raw materials by weight parts;

[0019] S2. Knead and continuously vulcanize the weighed rubber raw materials to form a seal matrix;

[0020] S3. After surface cleaning the vulcanized seal matrix, spray a coating and cure it in a drying oven;

[0021] S4. After treating the two ends of the cured seal matrix and applying an adhesive, cold bond it into an annular seal to complete the manufacture of the seal for high-efficiency sealing of the internal floating roof.

[0022] Furthermore, in step S1, the rubber raw materials include raw rubber, filler, crosslinking agent, crosslinking aid and plasticizer; the raw rubber is a rubber compound containing -CH2CH(CN)- bonds.

[0023] Furthermore, step S1 is specifically as follows:

[0024] Weigh 100 parts by weight of raw rubber, 1 - 50 parts of carbon black, 1 - 40 parts of conductive filler, 1 - 30 parts of flame retardant filler, 1 - 5 parts of crosslinking agent, 1 - 20 parts of crosslinking aid, and 1 - 50 parts of plasticizer;

[0025] The raw rubber is hydrogenated nitrile rubber, the acrylonitrile content of the hydrogenated nitrile rubber is 15 - 50 wt%, the residual double bond content ≤ 5 wt%, and the Mooney viscosity at 121°C, ML1+10min is 65 - 75 MU; where M represents Mooney, L represents using a large rotor, 1 represents preheating for 1 minute, and 10 represents testing for 10 minutes;

[0026] The filler includes carbon black and functional filler; the carbon black is any one of high abrasion furnace black N330 series, cement mortar carbon black, thermal cracking carbon black N990 series and semi-reinforcing carbon black N550 series; the functional filler includes conductive filler and flame retardant filler; the conductive filler is any one or a combination of conductive carbon black, graphite, carbon fiber and metal powder; the flame retardant filler is any one or a combination of aluminum hydroxide, silica, chlorinated paraffin and perchlorocyclopentane;

[0027] The crosslinking agent is any one or a combination of sulfur, dicumyl peroxide and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane;

[0028] The crosslinking aid includes any one or a combination of calcium oxide, zinc oxide and stearic acid;

[0029] The plasticizer includes dioctyl phthalate vulcanizing agent.

[0030] Furthermore, step S2 is specifically as follows:

[0031] S21. Set the initial mixing temperature of the internal mixer to 65 - 75 °C and the rotor speed to 50 - 70 r / min. After the internal mixer reaches the initial temperature, place the weighed raw materials into the mixing chamber of the internal mixer and mix them evenly.

[0032] S22. Set the discharge temperature of the internal mixer ≤ 120 °C. After mixing the raw materials evenly in the internal mixer for 5 - 15 min, pass them thinly through the open mill 5 - 10 times and cut into sheets to obtain the mixed rubber.

[0033] S23. Set the traction speed of the extruder to 1 - 3 m / min and the extrusion pressure to 15 - 20 MPa. Place the mixed rubber into the extruder for continuous vulcanization at a vulcanization temperature of 160 - 180 °C to form the seal body.

[0034] Step S3 is specifically as follows:

[0035] After surface cleaning the vulcanized seal body, spray a coating with a concentration of 5 - 15 wt% and cure it in a hot air drying oven at 50 - 70 °C; the coating is any one or a combination of polytetrafluoroethylene, polyurethane, polyurea, and silicone.

[0036] Step S4 is specifically as follows:

[0037] Sand the two ends of the cured seal body. After sanding, apply an adhesive to the two ends and press firmly for 30 - 60 s, then cure at room temperature for 4 - 8 h to cold - bond it into an annular seal, completing the manufacture of the seal for high - efficiency sealing of the internal floating roof.

[0038] In addition, for the seal for high - efficiency sealing of the internal floating roof and the back plate of the internal floating roof in the present invention, the special feature is:

[0039] The back plate is in an S shape, with the S - shaped back plate horizontally inverted. One side is connected to the U - shaped structure, and the other side is used to connect to the corresponding structure arranged on the outer edge of the internal floating roof; the inner side of the brush handle is connected to the internal floating roof through the S - shaped back plate. The back plate is used to provide support for the oil - scraping brush and the sealing brush to achieve transitional and interference contact with the tank wall of the oil tank.

[0040] The beneficial effects of the present invention:

[0041] 1. For the seal for high - efficiency sealing of the internal floating roof in the present invention, the upward - guiding part improves the ability to pass through the uneven welds of the tank wall during upward movement; the downward - guiding part improves the ability to pass through the uneven welds of the tank wall during downward movement; the oil - scraping brush makes transitional contact with the tank wall of the oil tank during the downward movement in the oil tank to achieve the aggregation of residual oil products; the sealing brush makes interference contact with the tank wall of the oil tank during the operation or still state in the oil tank to achieve high - efficiency sealing; the present invention can integrate the functions of guiding, sealing, and oil - scraping, enabling the VOCs emission during the oil storage process to be controlled within 400 mg / m 3During operation, the VOC emission index can be controlled below 500 mg / m 3 below.

[0042] 2. For the seal for efficient sealing of the internal floating roof of the present invention, the two oil scraping brushes and two sealing brushes provided reduce the overall weight of the product by 20%, and the installation is simple and the maintainability is more reliable.

[0043] 3. For the seal for efficient sealing of the internal floating roof of the present invention, the transition amount between the outer edges of the two oil scraping brushes and the oil tank wall is equal or gradually changes from top to bottom; the interference amount between the two sealing brushes and the oil tank wall is equal or gradually changes from top to bottom, which can achieve a better sealing effect and reduce the emission of volatile organic compounds.

[0044] 4. In the seal for efficient sealing of the internal floating roof of the present invention, the value range of the first guiding angle is 45° to 60°, which facilitates the internal floating roof to pass through the circumferential weld of the tank wall during the ascending process; the value range of the second guiding angle is 22.5° to 30°, which facilitates the internal floating roof to pass through the circumferential weld of the tank wall during the descending process; the first guiding angle and the second guiding angle directly reduce the obstacle-crossing ability of the oil scraping brush and the sealing brush.

[0045] 5. For the seal for efficient sealing of the internal floating roof of the present invention, the transition amount between the outer edge of the oil scraping brush and the oil tank wall is 0 to 0.1, and the interference amount between the sealing brush and the oil tank wall is 0.5 to 1.5 mm, which can minimize the frictional force while ensuring the sealing effect.

[0046] 6. For the seal for efficient sealing of the internal floating roof of the present invention, the brush handle, the upward guiding part, the oil scraping brush, the sealing brush, and the downward guiding part are an integrated annular structure, and the product size can be determined according to actual needs. The integrated strip structure only retains one joint, making the production simpler.

[0047] 7. For the manufacturing method of the seal for efficient sealing of the internal floating roof of the present invention, it is manufactured using the raw rubber of a rubber compound containing -CH2CH(CN)- bonds, and its surface is sprayed with a wear-resistant coating, so that the service life of the product can reach 18 years.

[0048] 8. For the manufacturing method of the seal for efficient sealing of the internal floating roof of the present invention, the seal obtained by continuous vulcanization only retains one joint, improving the reliability.

[0049] 9. For the manufacturing method of the seal for efficient sealing of the internal floating roof of the present invention, the strength of the bonded seal can reach 80% of the strength of the main body by using the cold bonding process, and the bonding process is simple and reliable.

[0050] 10. In the present invention, a back plate of a seal for efficient sealing of an internal floating roof can provide support for an oil scraping brush and a sealing brush to achieve transitional and interference contact with the tank wall of the oil tank. Under a stress of 14 N, its maximum deformation can reach 1.5 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 FIG. is a schematic structural diagram of an embodiment of a seal for efficient sealing of an internal floating roof according to the present invention.

[0052] DESCRIPTION OF THE REFERENCE NUMERALS:

[0053] 1 - brush handle, 2 - upward guiding part, 3 - oil scraping brush, 4 - sealing brush, 5 - downward guiding part, 6 - brush body. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] Embodiment 1

[0055] As Figure 1 shown, a seal for efficient sealing of an internal floating roof is provided between the internal floating roof and the tank wall of the oil tank and is connected to the outer edge of the internal floating roof. It includes a back plate, a brush body 6, a brush handle 1 connected to the side of the brush body 6 close to the internal floating roof, an upward guiding part 2, N oil scraping brushes 3, M sealing brushes 4, and a downward guiding part 5 arranged in sequence along the axial direction of the oil tank from top to bottom on the side of the brush body 6 close to the tank wall of the oil tank. The brush handle 1, the upward guiding part (2), N oil scraping brushes 3, M sealing brushes 4, the downward guiding part 5, and the brush body 6 are integrally provided, and their materials are all rubber materials; N ≥ 1, M ≥ 1.

[0056] The inner side of the brush handle 1 is used to connect to the internal floating roof. The brush handle 1 is a U-shaped structure with an opening facing the brush body 6. The bottom of the U-shaped structure is used to connect to the internal floating roof, and any one side wall of the U-shaped structure is connected to the brush body 6. The U-shaped structure is composed of 4 - 6 mm of rubber, with a 1 mm gap and a 4 mm diameter round hole left in the middle. This U-shaped structure can strengthen the connection with the internal floating roof.

[0057] The upward guiding part 2 is used for guiding the inner floating roof during the rising process in the oil tank, improving the ability to pass through the uneven welds of the tank wall during upward movement; the angle between the outer side wall of the upward guiding part 2 and the horizontal plane is the first guiding angle, and the value range of the first guiding angle is 40° to 65°. The downward guiding part 5 is used for guiding the inner floating roof during the descending process in the oil tank, improving the ability to pass through the uneven welds of the tank wall during downward movement; the angle between the outer side wall of the downward guiding part 5 and the horizontal plane is the second guiding angle, and the value range of the second guiding angle is 20° to 35°. The outer edge size of the oil scraping brush 3 is set according to the following rule: the outer edge of the oil scraping brush 3 has an interference fit with the tank wall of the oil tank, and is used for scraping and gathering the residual oil products on the tank wall of the oil tank during the descending process of the inner floating roof in the oil tank; the outer edge size of the sealing brush 4 is set according to the following rule: the outer edge of the sealing brush 4 has an interference fit with the tank wall of the oil tank, and is used for making an interference contact with the tank wall of the oil tank during the running or static process of the inner floating roof in the oil tank, so as to reduce the emission of volatile organic compounds; the upward guiding part 2 is smoothly connected to the side wall of the uppermost oil scraping brush among the N oil scraping brushes 3; the downward guiding part 5 is smoothly connected to the side wall of the lowermost sealing brush among the M sealing brushes 4. The sealing member for efficient sealing of the inner floating roof of the present invention reduces the emission of volatile organic compounds (VOCs) through scraping and sealing.

[0058] The interference amount between the outer edges of the N oil scraping brushes 3 and the tank wall of the oil tank is equal or gradually changes from top to bottom; the interference amount between the M sealing brushes 4 and the tank wall of the oil tank is equal or gradually changes from top to bottom; preferably, the interference amount between the outer edges of the N oil scraping brushes 3 and the tank wall of the oil tank gradually increases from top to bottom; the interference amount between the outer edges of the M sealing brushes 4 and the tank wall of the oil tank gradually increases from top to bottom, which can better achieve the sealing effect and reduce the emission of volatile organic compounds. The value range of the first guiding angle is 45° to 60°, which makes it convenient for the inner floating roof to pass through the circumferential weld of the tank wall during the rising process; the value range of the second guiding angle is 22.5° to 30°, which makes it convenient for the inner floating roof to pass through the circumferential weld of the tank wall during the descending process; the sizes of the chamfers (i.e., the first guiding angle and the second guiding angle) of the upward guiding part 2 and the downward guiding part 5 affect the obstacle-crossing ability of the oil scraping brush 3 and the sealing brush 4. The value of N is 2, and the value of M is 2, which can make the weight of the sealing member for efficient sealing of the inner floating roof lighter and the sealing more reliable.

[0059] In this embodiment, the length of the brush teeth of the oil scraping brush 3 (the radial length along the inner floating roof) is 7-8 mm, the angle between the upper side wall and the lower side wall of the inclination angle of the brush teeth is 20°-25°, the top is arc transition, the root width of the brush teeth is 4-5 mm, and the distance between adjacent brush teeth is 6-7 mm; during the downward movement of the inner floating roof, the oil scraping brush 3 has a transition fit with the tank wall of the oil tank, and the transition amount is 0-0.1. The outer edge of the oil scraping brush 3 can scrape and gather the oil remaining on the tank wall of the oil tank and transfer it to the inside of the storage tank at an appropriate time. The length of the brush teeth of the sealing brush 4 is 7-8 mm, the angle between the upper side wall and the lower side wall of the inclination angle of the brush teeth is 20°-25°, the top is arc transition, the root width of the brush teeth is 4-5 mm, and the distance between adjacent brush teeth is 6-7 mm. The distance between the lowest one of the N oil scraping brushes 3 and the uppermost one of the M sealing brushes 4 is 6-7 mm. During the operation and static state of the inner floating roof, the outer edge of the sealing brush 4 has an interference fit with the tank wall of the oil tank to achieve efficient sealing, and the interference amount is 0.5-1.5 mm, which can minimize the frictional force on the premise of ensuring the sealing effect.

[0060] Preferably, the brush handle 1, the upward guiding part 2, the oil scraping brush 3, the sealing brush 4, and the downward guiding part 5 are of an integral ring structure. The product size is determined according to actual needs. The integral strip structure only retains one joint to improve reliability.

[0061] In the present invention, a sealing member for efficient sealing of an inner floating roof and the back plate of the inner floating roof, the back plate is of S shape, the S-shaped back plate is horizontally inverted, one side of which is connected to a U-shaped structure, and the other side is used to be connected to a corresponding structure arranged on the outer edge of the inner floating roof; the inner side of the brush handle 1 is connected to the inner floating roof through the S-shaped back plate. The back plate is used to provide a supporting force for the oil scraping brush 3 and the sealing brush 4 to achieve transition and interference contact with the tank wall of the oil tank. Under a stress of 14 N, its maximum deformation can reach 1.5 mm.

[0062] At the same time, the present invention also provides a manufacturing method of the above-mentioned sealing member for efficient sealing of an inner floating roof, including the following steps:

[0063] S1. Weigh the required rubber raw materials by weight; the rubber raw materials are 100 parts of raw rubber, 1-50 parts of carbon black, 1-40 parts of conductive filler, 1-30 parts of flame retardant filler, 1-5 parts of cross-linking agent, 1-20 parts of cross-linking auxiliary agent, and 1-50 parts of plasticizer; the raw rubber is a rubber compound containing -CH2CH(CN)- bonds, and its chemical structural formula is as follows:

[0064]

[0065] Among them, both x and y are positive integers;

[0066] In the present invention, the rubber compound containing -CH2CH(CN)- bonds has excellent mechanical properties, antistatic properties and flame retardant properties, and has at least one of the following properties: (a) Under the test conditions of GB / T528-1998, the tensile strength is not less than 16 MPa; the elongation at break is not less than 400%; (b) Under the test conditions of GB / T529-2008, the tear strength is not less than 35 N / mm; (c) Under the test conditions of GB / T11210-2014, the resistance is not higher than 10 8 ohms; (d) Under the test conditions of GB / T10707-2008, the combustion rating is not higher than FV-2 rating.

[0067] In this embodiment, the raw rubber is hydrogenated nitrile rubber, which is obtained by selectively hydrogenating the double bonds in the main chain of nitrile rubber. The specific rubber compound containing -CH2CH(CN)- bonds can be selected according to the molecular weight of the hydrogenated nitrile rubber. The wear resistance of the hydrogenated nitrile rubber is positively correlated with the acrylonitrile content. The higher the acrylonitrile content, the better the wear resistance of the material, but the worse the low temperature resistance of the material. Therefore, the acrylonitrile content needs to be determined according to the use requirements.

[0068] The acrylonitrile content of the hydrogenated nitrile rubber is 15-50 wt%, and the residual double bond content ≤ 5 wt%; the Mooney viscosity at 121 °C, ML1+10min is 65-75 MU, where M represents Mooney, L represents using the large rotor, 1 represents preheating for 1 minute, and 10 represents the test for 10 minutes; that is, at 121 °C, using the large rotor to rotate the hydrogenated nitrile rubber, preheating for 1 min, and the rotation test time is 10 min, the Mooney viscosity of the hydrogenated nitrile rubber can be obtained as 65-75 MU; the Mooney viscosity is used to reflect the processing performance of the rubber compound, the high and low molecular weight and the width of the distribution range. The larger the Mooney value, the greater the viscosity and the lower its plasticity.

[0069] The filler includes carbon black and functional filler; the carbon black is any one of high abrasion furnace black N330 series, cement mortar carbon black, thermal cracking carbon black N990 series and semi-reinforcing furnace black N550 series; the carbon black is the carbon black that can endow the product with special performance requirements, such as high abrasion furnace black, which can endow the product with better wear resistance; selecting different types of carbon black additives can play a reinforcing and filling role to improve the comprehensive performance of the rubber compound containing -CH2CH(CN)- bonds, such as mechanical properties, etc.

[0070] The functional filler includes conductive filler and flame retardant filler; the conductive filler is any one or a combination of conductive carbon black, graphite, carbon fiber and metal powder; selecting different types of conductive filler additives can play a conductive performance to improve the antistatic performance of the rubber compound containing -CH2CH(CN)- bonds.

[0071] The flame retardant filler is any one or a combination of more than one of aluminum hydroxide, silica, chlorinated paraffin, and perchlorocyclopentane; selecting different types of flame retardant fillers can improve the flame retardant performance of the compound, so as to improve the flame retardant performance of the rubber compound containing -CH2CH(CN)- bonds.

[0072] The crosslinking agent is any one or a combination of more than one of sulfur (vulcanizing agent), dicumyl peroxide, and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane; the crosslinking agent can form bridging bonds, such as vulcanization bonds, between the molecular chains of the same or different rubber compounds, and then crosslink the rubber compound containing -CH2CH(CN)- bonds to form a three-dimensional network structure with larger molecular chains, so as to improve the mechanical properties of the rubber compound.

[0073] The crosslinking aid includes any one or a combination of more than one of calcium oxide, zinc oxide, and stearic acid; the crosslinking aid can provide more reactive sites, and the types of functional groups, the number of functional groups, the polarity of the molecule, and the molecular weight of the crosslinking aid will all affect the crosslinking efficiency or vulcanization efficiency of the rubber compound containing -CH2CH(CN)- bonds; at the same time, the polarity of the crosslinking aid will also affect its solubility in the rubber compound containing -CH2CH(CN)- bonds, and then affect the crosslinking degree of the rubber compound containing -CH2CH(CN)- bonds. The plasticizer includes dioctyl phthalate vulcanizing agent. In the present invention, hydrogenated nitrile rubber, carbon black, conductive carbon black, flame retardant, crosslinking agent, crosslinking aid, and plasticizer are selected, and certain physical and chemical combinations can occur between the substances, and then a seal for the inner floating roof with high efficiency is formed, which has good sealing performance and mechanical properties.

[0074] S2. Knead and vulcanize the weighed raw materials to form a seal matrix, specifically:

[0075] S21. Set the initial kneading temperature of the internal mixer to 65 - 75°C and the rotor speed to 50 - 70 r / min. After the internal mixer reaches the initial temperature, place the weighed raw materials in the kneading chamber of the internal mixer and mix them evenly.

[0076] S22. Set the discharge temperature of the internal mixer ≤120°C, and knead the raw materials evenly mixed in the internal mixer for 5 - 15 min, then pass them through the two-roll mill thinly for 5 - 10 times, and cut into sheets to obtain the kneaded rubber.

[0077] S23. Set the traction speed of the extruder to 1 - 3 m / min and the extrusion pressure to 15 - 20 MPa. Place the kneaded rubber in the extruder for continuous vulcanization, and the vulcanization temperature is 160 - 180°C to form a seal matrix.

[0078] S3. After surface cleaning the vulcanized seal matrix, spray a coating with a concentration of 5 - 15 wt%, and cure it in a hot air duct at 50 - 70°C; the coating is any one or a combination of polytetrafluoroethylene, polyurethane, polyurea, and silicone. Spraying different types of coatings can improve the wear resistance and lubricity of the sealing brush 4;

[0079] S4. Sand the two ends of the cured seal matrix. After sanding, apply an adhesive to the two ends, and cold-bond it into an annular seal, thus completing the manufacturing of the seal for the high-efficiency seal of the internal floating roof. Among them, after applying the adhesive, press it firmly for 30 - 60 s, and then cure it at room temperature for 4 - 8 h. The two ends are strongly bonded into an annular seal, and the bonding strength is not less than 80% of the strength of the main body.

[0080] In the first embodiment, the manufacturing method of the seal for the high-efficiency seal of the internal floating roof includes the following steps:

[0081] S1. Weigh the required rubber raw materials by weight: 100 parts of hydrogenated nitrile rubber (acrylonitrile content is 43 wt%, residual double bond content is 2.0 wt%), 40 parts of high-abrasion carbon black N330 series, 10 parts of conductive carbon black, 30 parts of aluminum hydroxide, 10 parts of calcium oxide, 5 parts of zinc oxide, 1 part of stearic acid, 50 parts of dioctyl phthalate, and 3 parts of vulcanizing agent; in the first embodiment, sulfur is selected as the cross-linking agent, which has a relatively high cross-linking degree, thereby improving the sealing performance and mechanical properties, and enabling it to have a long service life in a harsh environment.

[0082] S21. Set the starting temperature of the internal mixer to 70°C and the rotor speed to 60 r / min. After the internal mixer reaches the starting temperature, put the raw materials weighed in step S1 into the mixing chamber of the internal mixer and mix them evenly;

[0083] S22. Set the discharge temperature of the internal mixer to 110°C, and knead the raw materials evenly mixed in the internal mixer for 10 min, then pass them thinly through the open mill 5 times, and take off the sheet to obtain the kneaded rubber;

[0084] S23. Place the kneaded rubber in an extruder for continuous vulcanization to form a seal matrix; the vulcanization temperature is 180°C, the traction speed of the extruder is 3 m / min, and the extrusion pressure is 20 MPa;

[0085] S3. Perform surface treatment on the vulcanized seal matrix, and spray a polyurethane coating solution with a concentration of 10 wt% on its surface. After spraying, put the sealing brush 4 into a hot air duct at 60°C for high-temperature curing;

[0086] S4. Sand the two cut ends of the cured seal matrix with sandpaper. After sanding, apply an adhesive to the two cut ends, press firmly for 30 s, and then cure at room temperature for 4 h to cold-bond it into a No. 1 annular seal, thus completing the manufacturing of the seal for high-efficiency sealing of the internal floating roof.

[0087] Example 2

[0088] S1. Weigh the required rubber raw materials by weight: 100 parts of hydrogenated nitrile rubber (acrylonitrile content is 15 wt%, residual double bond content is 3.0 wt%), 30 parts of semi-reinforcing carbon black N550 series, 20 parts of metal powder, 30 parts of perchlorocyclopentane, 10 parts of calcium oxide, 5 parts of zinc oxide, 1 part of stearic acid, 50 parts of dioctyl phthalate, and 3 parts of diisopropylbenzene peroxide and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane;

[0089] S21. Set the starting temperature of the internal mixer to 65 °C and the rotor speed to 50 r / min. After the internal mixer reaches the starting temperature, put the raw materials weighed in step S1 into the mixing chamber of the internal mixer and mix evenly;

[0090] S22. Set the discharge temperature of the internal mixer to 100 °C, and after kneading the raw materials evenly mixed in the internal mixer for 9 min, pass them thinly through the open mill 6 times and take off the sheet to obtain the kneaded rubber;

[0091] S23. Place the kneaded rubber in an extruder for continuous vulcanization to form a seal matrix; the vulcanization temperature is 160 °C, the traction speed of the extruder is 1 m / min, and the extrusion pressure is 15 MPa;

[0092] S3. Perform surface treatment on the vulcanized seal matrix, spray a polytetrafluoroethylene coating solution with a concentration of 5 wt% on its surface, and after spraying, put the sealing brush 4 into a hot air drying oven at 50 °C for high-temperature curing;

[0093] S4. Sand the two cut ends of the cured seal matrix with sandpaper. After sanding, apply an adhesive to the two cut ends, press firmly for 40 s, and then cure at room temperature for 3 h to cold-bond it into a No. 2 annular seal, thus completing the manufacturing of the seal for high-efficiency sealing of the internal floating roof.

[0094] Example 3

[0095] S1. Weigh the required rubber raw materials by weight: 100 parts of hydrogenated nitrile rubber (acrylonitrile content is 50 wt%, residual double bond content is 4.0 wt%), 20 parts of cement mortar carbon black, 30 parts of graphite, 30 parts of silica, 10 parts of calcium oxide, 5 parts of zinc oxide, 1 part of stearic acid, 50 parts of dioctyl phthalate, and 3 parts of sulfur;

[0096] S21. Set the starting temperature of the internal mixer to 75 °C and the rotor speed to 55 r / min. After the internal mixer reaches the starting temperature, put the raw materials weighed in step S1 into the mixing chamber of the internal mixer and mix them evenly.

[0097] S22. Set the discharging temperature of the internal mixer to 115 °C. After mixing the raw materials evenly in the internal mixer for 6 min, pass them thinly through the open mill 8 times and take off the sheet to obtain the mixed rubber.

[0098] S23. Place the mixed rubber in an extruder for continuous vulcanization to form a seal matrix. The vulcanization temperature is 175 °C, the traction speed of the extruder is 2 m / min, and the extrusion pressure is 20 MPa.

[0099] S3. Perform surface treatment on the vulcanized seal matrix and spray a polyurea coating solution with a concentration of 15 wt% on its surface. After spraying, put the sealing brush 4 into a hot drying channel at 70 °C for high-temperature curing.

[0100] S4. Grind the two end fracture surfaces of the cured seal matrix with sandpaper. After grinding, apply an adhesive to the two end fracture surfaces, press firmly for 50 s, and then cure at room temperature for 5 h to cold-bond it into a No. 3 annular seal, completing the manufacture of the seal for high-efficiency sealing of the internal floating roof.

[0101] Example 4

[0102] S1. Weigh the required rubber raw materials by weight: 100 parts of hydrogenated nitrile rubber (acrylonitrile content is 15 wt%, residual double bond content is 5.0 wt%), 10 parts of thermal cracking carbon black N990 series, 40 parts of carbon fiber, 30 parts of chlorinated paraffin, 10 parts of calcium oxide, 5 parts of zinc oxide, 1 part of stearic acid, 50 parts of dioctyl phthalate, and 3 parts of sulfur.

[0103] S21. Set the starting temperature of the internal mixer to 60 °C and the rotor speed to 70 r / min. After the internal mixer reaches the starting temperature, put the raw materials weighed in step S1 into the mixing chamber of the internal mixer and mix them evenly.

[0104] S22. Set the discharging temperature of the internal mixer to 105 °C. After mixing the raw materials evenly in the internal mixer for 8 min, pass them thinly through the open mill 7 times and take off the sheet to obtain the mixed rubber.

[0105] S23. Place the mixed rubber in an extruder for continuous vulcanization to form a seal matrix. The vulcanization temperature is 165 °C, the traction speed of the extruder is 3 m / min, and the extrusion pressure is 16 MPa.

[0106] S3. Surface-treat the vulcanized seal base body, spray an organosilicon coating solution with a concentration of 10 wt% on its surface. After spraying, put the sealing brush 4 into a hot air drying oven at 55 °C for high-temperature curing;

[0107] S4. Grind the two ends of the cured seal base body with sandpaper. After grinding, apply an adhesive to the two ends. After pressing firmly for 60 s, cure at room temperature for 8 h to cold-bond it into a No. 4 ring seal, thus completing the manufacture of the seal for high-efficiency sealing of the internal floating roof.

[0108] It should be noted that the raw rubber in the present invention is the matrix material for manufacturing the seal, referring to the unvulcanized rubber compound, and its internal structure is generally a linear chain structure. "wt%" represents mass percentage or weight percentage; "parts by weight" refers to the basic measurement unit of the weight ratio relationship of multiple components. 1 part can represent any unit mass. For example, 1 part can be expressed as 1 g, can be expressed as 1.8 g, or can also be expressed as 5 g, etc. Part is a mass unit of "parts per 100 grams", indicating the content added per 100 parts by weight.

[0109] Test Example

[0110] Test the mechanical properties, antistatic properties and flame retardant properties of the No. 1 ring seal, No. 2 ring seal, No. 3 ring seal and No. 4 ring seal obtained in Example 1, Example 2, Example 3 and Example 4 respectively according to the methods listed in Table 2 at a test temperature of 23 °C. The test results are shown in Table 2:

[0111] Table 2

[0112]

[0113]

[0114] It can be seen from Table 2 that the flame retardancy of the four examples all reaches the FV-2 level, meeting the flame retardant requirements; the hardness, tensile strength at break and tear strength of Example 1 are better than those of Example 2, Example 3 and Example 4; the elongation at break and antistatic properties of Example 4 are better than those of Example 1, Example 2 and Example 3. Among them, the comprehensive performance of Example 3 is the best, which can meet (a) under the test conditions of GB / T528-1998, the tensile strength at break is not less than 16 MPa; the elongation at break is not less than 400%; (b) under the test conditions of GB / T529-2008, the tear strength is not less than 35 N / mm; (c) under the test conditions of GB / T11210-2014, the resistance is not higher than 10 8 ohms; (d) under the test conditions of GB / T10707-2008, the combustion grade is not higher than the requirements of the FV-2 level.

Claims

1. A seal for efficient sealing of an internal floating roof, which is arranged between the internal floating roof and the tank wall of the oil tank and is connected to the outer edge of the internal floating roof; characterized in that: It includes a brush body (6), a brush handle (1) connected to the side of the brush body (6) close to the inner floating roof, an upward guiding part (2), N scraping brushes (3), M sealing brushes (4), and a downward guiding part (5) which are arranged on the side of the brush body (6) close to the oil tank wall in sequence from top to bottom along the axial direction of the oil tank; N≥1, M≥1; the brush handle (1), the upward guiding part (2), the N scraping brushes (3), the M sealing brushes (4), the downward guiding part (5) and the brush body (6) are integrally arranged, and their materials are all rubber materials; The inner side of the brush handle (1) is used for connecting with the inner floating roof; The upward guiding part (2) is used for guiding the inner floating roof during its rising process in the oil tank, and the included angle between its outer side wall and the horizontal plane is the first guiding angle, and the value range of the first guiding angle is 40° - 65°; The downward guiding part (5) is used for guiding the inner floating roof during its descending process in the oil tank, and the included angle between its outer side wall and the horizontal plane is the second guiding angle, and the value range of the second guiding angle is 20° - 35°; The outer edge size of the scraping brush (3) is set according to the following rule: the outer edge of the scraping brush (3) has an interference fit with the oil tank wall, and is used for scraping and gathering the residual oil on the oil tank wall during the descending process of the inner floating roof in the oil tank; The outer edge size of the sealing brush (4) is set according to the following rule: the outer edge of the sealing brush (4) has an interference fit with the oil tank wall, and is used for the interference contact with the oil tank wall during the running or static process of the inner floating roof in the oil tank to reduce the emission of volatile organic compounds; The upward guiding part (2) is smoothly connected to the side wall of the uppermost scraping brush (3) among the N scraping brushes (3); the downward guiding part (5) is smoothly connected to the side wall of the lowermost sealing brush (4) among the M sealing brushes (4).

2. The seal for high - efficiency sealing of an inner floating roof according to claim 1, wherein: The interference amount between the outer edges of the N scraping brushes (3) and the oil tank wall is equal or gradually changes from top to bottom; The interference amount between the M sealing brushes (4) and the oil tank wall is equal or gradually changes from top to bottom.

3. The seal for high - efficiency sealing of an inner floating roof according to claim 1 or 2, wherein: The value range of the first guiding angle is 45° - 60°; The value range of the second guiding angle is 22.5° - 30°; The interference amount between the outer edge of the scraping brush (3) and the oil tank wall is 0 - 0.1; The interference amount between the outer edge of the sealing brush (4) and the oil tank wall is 0.5 - 1.5 mm; The value of N is 2.

4. The seal for high - efficiency sealing of an inner floating roof according to claim 3, wherein: The brush handle (1) is a U - shaped structure with an opening facing the brush body (6), the U - shaped bottom is used for connecting with the inner floating roof, and any one side wall of the U - shaped structure is connected to the brush body (6); The brush handle (1), the upward guiding part (2), the scraping brush (3), the sealing brush (4), and the downward guiding part (5) are an integral ring - shaped structure.

5. The seal for high - efficiency sealing of an inner floating roof according to claim 4, wherein: The brush teeth of the oil scraping brush (3) have a length of 7 - 8 mm, the included angle between the upper side wall and the lower side wall of the brush tooth inclination angle is 20° - 25°, the top is arc-shaped transition, the root width of the brush teeth is 4 - 5 mm, and the spacing between adjacent brush teeth is 6 - 7 mm; The brush teeth of the sealing brush (4) have a length of 7 - 8 mm, the included angle between the upper side wall and the lower side wall of the brush tooth inclination angle is 20° - 25°, the top is arc-shaped transition, the root width of the brush teeth is 4 - 5 mm, and the spacing between adjacent brush teeth is 6 - 7 mm; The brush tooth spacing between the lowermost one of the N oil scraping brushes (3) and the uppermost one of the M sealing brushes (4) is 6 - 7 mm.

6. A manufacturing method of a seal for highly efficient sealing of an internal floating roof according to any one of claims 1 to 5, characterized in that, It includes the following steps: S1. Weigh the required rubber raw materials by weight parts; S2. Knead and continuously vulcanize the weighed rubber raw materials to form a sealing member matrix; S3. After surface cleaning the vulcanized sealing member matrix, spray a coating and cure it in a baking tunnel; S4. After treating the two ends of the cured sealing member matrix and applying an adhesive, cold bond it into an annular sealing member to complete the manufacturing of the sealing member for high-efficiency sealing of the internal floating roof.

7. The manufacturing method of the sealing member for high-efficiency sealing of the internal floating roof according to claim 6, characterized in that: In step S1, the rubber raw materials include raw rubber, filler, cross-linking agent, cross-linking assistant and plasticizer; the raw rubber is a rubber compound containing -CH2CH(CN)- bonds.

8. The manufacturing method of a seal for efficient sealing of an internal floating roof according to claim 7, characterized in that, Step S1 is specifically: Weigh 100 parts of raw rubber, 1 - 50 parts of carbon black, 1 - 40 parts of conductive filler, 1 - 30 parts of flame retardant filler, 1 - 5 parts of cross-linking agent, 1 - 20 parts of cross-linking assistant, and 1 - 50 parts of plasticizer by weight parts; The raw rubber is hydrogenated nitrile rubber, the acrylonitrile content of the hydrogenated nitrile rubber is 15 - 50 wt%, the residual double bond content ≤ 5 wt%, and the Mooney viscosity at 121 °C, ML1+10min is 65 - 75 MU; where M represents Mooney, L represents using a large rotor, 1 represents preheating for 1 minute, and 10 represents testing for 10 minutes; The filler includes carbon black and functional filler; the carbon black is any one of high abrasion furnace black N330 series, cement mortar carbon black, thermal cracking carbon black N990 series and semi-reinforcing carbon black N550 series; the functional filler includes conductive filler and flame retardant filler; the conductive filler is any one or a combination of conductive carbon black, graphite, carbon fiber and metal powder; the flame retardant filler is any one or a combination of aluminum hydroxide, silica, chlorinated paraffin and perchlorocyclopentane; The cross-linking agent is any one or a combination of sulfur, dicumyl peroxide and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane; The cross-linking assistant includes any one or a combination of calcium oxide, zinc oxide and stearic acid; The plasticizer includes dioctyl phthalate vulcanizing agent.

9. The manufacturing method of a seal for efficient sealing of an internal floating roof according to claim 8, characterized in that, Step S2 is specifically: S21. Set the initial mixing temperature of the internal mixer to 65 - 75 °C, the rotor speed to 50 - 70 r / min. After the internal mixer reaches the initial temperature, place the weighed raw materials in the mixing chamber of the internal mixer and mix them evenly; S22. Set the discharge temperature of the internal mixer ≤ 120 °C. After kneading the uniformly mixed raw materials in the internal mixer for 5 - 15 min, pass them thinly through the open mill 5 - 10 times, and cut into sheets to obtain the kneaded rubber. S23. Set the traction speed of the extruder at 1 - 3 m / min and the extrusion pressure at 15 - 20 MPa. Place the kneaded rubber in the extruder for continuous vulcanization at a vulcanization temperature of 160 - 180 °C to form the seal base. Step S3 specifically includes: After surface cleaning the vulcanized seal base, spray a coating with a concentration of 5 - 15 wt%, and cure it in a hot air drying oven at 50 - 70 °C; the coating is any one or a combination of polytetrafluoroethylene, polyurethane, polyurea, and silicone. Step S4 specifically includes: Sand the two ends of the cured seal base. After sanding, apply an adhesive to the two ends, press firmly for 30 - 60 s, and then cure at room temperature for 4 - 8 h to cold - bond it into an annular seal, completing the manufacture of the seal for high - efficiency sealing of the internal floating roof.

10. A back plate for the seal for high - efficiency sealing of the internal floating roof according to any one of claims 1 to 5 and the internal floating roof, characterized in that: The back plate is of S - shape, the S - shaped back plate is horizontally inverted, one side of which is connected to the U - shaped structure, and the other side is used to be connected to the corresponding structure provided at the outer edge of the internal floating roof. The inner side of the brush handle (1) is connected to the internal floating roof through the S - shaped back plate. The back plate is used to provide a supporting force for the oil scraping brush (3) and the sealing brush (4) to achieve transitional and interference contact with the tank wall of the oil tank.

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