1 Foreword At present, the development trend of foreign insulation technology is the pursuit of structural integrity and strict and seamless, light weight, thermal conductivity is small. The thermal insulation of horizontal containers currently used in Jibei Oilfield mainly adopts P855 perlite block structure. The insulation of storage tanks mainly adopts rock wool board (or glass wool board) structure, and manual construction and bundling methods are used, resulting in high labor intensity and poor overall tightness. (with seams) Large heat loss. According to investigations, after the P855 perlite insulation structure is applied for one to three years, cracking and slumping often occur. The non-fluorinated and temperature-resistant polyurethane spray foam insulation technology is characterized by its light weight and excellent thermal insulation performance. At present, it has been applied in the heat preservation of domestic metal containers, storage tanks, etc., and its closed cell rate is as high as 90%. The highest safe use temperature is 150 thermal conductivity of 0. 019 ~ 0.030W/mk, compressive strength of 0.15 ~ 0.45MPa, suitable for container insulation. In 2000, the electric dehydrator in Jibei Oilfield was field tested using a non-fluorinated, temperature-resistant polyurethane spray foam insulation technology. 2 Test site and the status of the insulation layer of the container The original insulation structure of Jibei Oilfield Electric Dehydrator: P855 perlite insulation structure, waterproof layer of glass silk cloth coating paint, internal water intrusion, strengthen steel strip rust and break, some P855 perlite block shedding , the iron leakage part of the corrosion. After the original insulation structure was removed, many loose rust layers and a large amount of white alkaline precipitates were found on the outer surface of the middle part of the 3 electric dehydrators. After sand blasting, a total of 20-30 pitting pits of 1cm2 to 10cm2 were found. According to the inspection by the Bureau of Pot Inspection, the maximum pit depth is 5.9mm (the original thickness of the steel plate is 14mm). Through the safety evaluation, the electric dehydrator can continue to be used. Etch pits were also found on the outer surfaces of the other 2 electric dehydrators, but the pit depth was small and the number was small. Analysis of insulation layer damage and corrosion: P855 perlite has a high water absorption rate (200%~900%). After absorbing water, it increases the load on the steel strip and the corrosion speed. The pearlite block is bonded to the container due to the material of the adhesive or construction. Insufficient; width, thickness of steel strip is not enough, easy to break after corrosion; glass fiber cloth brush waterproof coating outer sheath is poor in anti-aging properties, easy to crack, peeling; original anti-corrosion layer anti-corrosion performance is poor. Jibei Oilfield 3 Electric Dehydrators: D518 Temperature Resistant Epoxy (2 lanes, total thickness: 80um) + polyurethane foam sprayed layer (2 sprays, total thickness 30mm) + Aluminium-plastic composite panel (0. Sand blasting brush Anti-corrosion coating - spray fluorine-free polyurethane hard foam surface finishing ※ Outer protective layer to control the quality of the polyurethane foam spray layer, the indoor and in-situ ratio optimization test, preliminary identified a more appropriate formula of polyurethane foam, construction will be A The components (fluorine-free combination polyol) and the component B (non-fluorinated combined isocyanate) are mixed and sprayed in a certain proportion with a high-pressure foaming machine. The foaming is rapidly cured in 2 to 15 seconds into a fluorine-free polyurethane rigid foam. The foam is fully compliant with the "Montreal International Convention" which does not contain Freon which is destructive to the atmospheric ozone layer. Auxiliaries A and B are newly developed polyurethane additives for Daming Chemical Anticorrosive & Insulating Materials Engineering Co., Ltd. and do not contain organic tin. Harmful chemicals. The main properties of the thermal spray coating after optimization of the formulation are shown in Table 1. Table 1 Performance Index of Fluorine-Free Polyurethane Foam Appearance Density Thermal Conductivity Compression Strength Flame Retardant Performance Water Absorption (Volume) Light Yellow Hard Foam Surface Smoothness Fire self-extinguishing During the spraying process, the following advantages of the spraying construction process are discovered: Spraying construction of non-fluorine rigid polyurethane foam, integrating heat preservation, sealing, and waterproofing in one; complete work efficiency; thickness of insulation layer is generally 35mm, divided into 2 ~ 3 sprays up to the specified thickness, about 3 people per shift, about 500 sprays per day; good integrity, dense and seamless; the disadvantages of the spray construction process is that the construction environment temperature can not be lower than 20 °C, 3 wind above and In rainy days, construction is not possible; surface roughness is not ideal (but does not affect any other properties). It takes a certain amount of time to clear and level the surface. Control of the surface roughness needs further testing. Through field tests and preliminary technical and economic analysis over the past year, it has been preliminarily assumed that polyurethane foam spraying technology is technically economically viable as an overhaul technology for the P855 thermal insulation structure. Construction technology has been initially supported. Through indoor and field optimization tests, the material composition, proportioning, and construction process of the polyurethane foam spray integral molding and heat preservation technology were preliminarily determined. Excellent insulation performance, thermal insulation effect than P855 insulation structure is about 1 times higher. See Table 2, Table 3. Table 2 Insulation Material Site Sampling Test Results Comparison Compressive Strength (MPa) Water Absorption Thermal Conductivity (W, /m0K) Heat Resistance No. Insulation Material Apparent Density Sampling Site Size Change Rate Weight Change Rate, % Intensity Growth Rate, % Polyurethane Foam Field Spraying Jibei Oilfield Perlite Thermal Insulation Board Jibei Oilfield Polyethylene Foam Baoji North Oilfield Fiber Spraying Table 3 Insulation Performance Field Tracking Test Results Heat Insulation Structure Ambient Temperature (C) Container External Surface Temperature ( C) Insulation layer outer wall temperature (C) Heat flux density (WVm2) GB4272 standard allows maximum heat loss (WVm2) polyurethane foam spray layer (30mm 4mm thick aluminum-plastic composite panel (continued on page 28)) to suppress insulating parts or formed glass steel products Because the molecular structure of the resin is linear, it is not resistant to solvent corrosion. 3. Viscosity influence on the quality of graphite impregnation The porous electrode plate graphite is impregnated with low-viscosity phenolic resin, generally impregnated twice, and the micropore plug can be densely packed up to three times. The porosity of graphite is generally about 20% ~ 25%, the highest weight gain for the first impregnation is up to about 14%, and the second and third weight gain rate is only 2% ~ 3%, and the total weight gain rate is up to 17%. Most of the pores are filled by the first impregnation. It is very important to ensure the quality of the first impregnation. If the resin is not qualified for the first immersion, the immersion depth of the viscosities of the ambassadors is not enough, and the immersed depth cannot be increased after the second and third immersions after polymerization. If the phenomenon of overflow, blistering, etc. occurs after the first pass of polymerization, it is also difficult to eliminate it in the second third impregnation. When the general resin viscosity is measured with a 5 mm aperture funnel viscometer, 100 ml of resin flows out from the viscometer at 20° C. for 30 to 60 seconds. This viscosity has a good resin impregnation effect and can achieve an impregnation depth of more than 20 mm. High resin viscosity, impregnation depth is not enough, some microporous immersion does not get into the resin, the surface of the graphite pieces is too many resin liquids, and cleaning is not convenient. Through years of actual production, it has been shown that the phenolic resin and graphite impregnation of the joint production device and the production process are rationally designed, the investment is low, and the efficiency is high, saving a lot of manufacturing, maintenance and replacement costs. The floor space of the equipment is reduced by half, the process flow is simple, and the operation is convenient. The labor intensity of the workers is reduced, and the phenomenon of running, running, dripping and leaking is eliminated, so that the quality and output of the products are greatly improved.
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Connection: fit coupling 20mm(1/2"), male thread 1/4"
Body Material: PVC
Sealing Material: EPDM
Design pressure:1.0Mpa(PN10 bar)