Polyurethane foam foam dimensional stability: cold storage polyurethane foam in severe temperature changes or at a relatively low temperature will appear dimensional changes (as contraction), the size changes often reflect bubble cracking or falling off, and these will inevitably affect the normal use of cold storage. In addition to regular simulation of performance testing, more emphasis is placed on the selection of high quality materials: special energy polyether compound use so that the foam body mesh structure, greatly improving the foam low temperature resistance. At present, 4110 polyether commonly used in spraying materials contains a large number of functional components, and a large number of linear structures formed after reaction are difficult to be stable at low temperature; The use of the energy crosslinking agent also greatly improved the dimensional stability of the foam. The selected polyether adopts catalysis in the production stage, and the reaction is complete, so that the polyether maintains a high reaction rate (that is, it can react completely with black material); Some manufacturers in order to achieve foam appearance does not produce deformation phenomenon and add a hole component to foam material, reduce the bubble closed hole rate, achieve the effect of stable size,Trentay attemptHow much is the installation of cold storage, but it has sacrificed the thermal insulation performance of polyurethane cold storage insulation material foam.
Airtight construction of quick freezing storehouse: the modified atmosphere fresh-keeping storehouse is developed on the basis of the traditional high-temperature fresh-keeping storehouse, long-term cold storage installation, cold storage installation, cold storage construction, fruit fresh-keeping cold storage, medical cold storage, complete products, excellent quality and favorable price. There are also & ldquo; Air conditioning & rdquo; Function; However, the quick freezing storehouse is not a simple superposition of ordinary high temperature storehouse and air conditioning equipment. In order to adjust the gas composition in the storehouse quickly, it is necessary to ensure that the quick freezing storehouse has good air tightness. This has been confirmed by the theoretical research and a large number of practical experience of quick freezing warehouse.
Trentay attempt.The gap between the cooling fan and the storage plate shall be greater than the thickness of the cooling fan.
Some cold bridge prevention measures shall be taken at the joints between polyurethane insulation boards.
.The structure of contemporary cold storage is in the development trend of prefabricated building cold storage. It is made into prefabricated components of cold storage including steam barrier and heat insulation plate to ensure on-site assembly. Its advantage is that the project construction is convenient, rapid and movable, but the project cost is relatively high.
There are many kinds of cold storage. According to the material, it can be divided into color steel plate, stainless steel plate and salted steel. Among them, color steel plate has strong anti rust ability, but stainless steel plate has strong anti rust ability, while salted steel has both beautiful appearance and anti rust ability. According to the layout, it is divided into flat plate and wave plate. The former is flat after the surface material is formed, the thickness of stainless steel is 0.5mm and 0mm, without color requirements; The thickness of salted steel plate is 0.5mm without color requirements; The thickness of PE paint baking board is 0.5mm, 0.8mm ivory white, titanium white and white gray. The most important thing for the cold storage is the applicable temperature of the cold storage. It is divided according to the insulation thickness of the storage plate. The thickness of the sky floor of the 150 mm storage plate is 150 mm,Trentay attemptCold storage board cold storage installation, and the thickness of the vertical plate is 160 mm and 100 mm, which is suitable for the insulation conditions of - 25 ℃ ~ - 45 ℃; 100mm storage plate: the thickness of the ceiling plate is 100mm and the thickness of the vertical plate is 110mm, which is suitable for the thermal insulation conditions of 0 ℃ ~ - 25 ℃. The thickness of the ceiling plate and the vertical plate of 60mm storage plate is 60mm, which is suitable for the thermal insulation conditions above 0 ℃. In fact, there are many other classification methods of cold storage. Determined by the current processing technology, it can be divided into standard plate and non-standard plate according to the width and size range of warehouse plate, including standard plate vertical plate width wa = 900mm, heaven and earth plate width WB = 980mm, vertical angle plate W1 = 790mm, W2 = 840mm, W3 = 740mm and W4 = 880. The dimensions of non-standard plates are different from those of Wa, WB and W4.
The combined cold storage does not cool or the cooling effect is poor. Check whether the condenser of the refrigerator is dirty. Whether frost is too thick on the evaporator in the warehouse. Check whether the refrigerant is leaking (apply soapy water to the pipeline connection, and if bubbles are generated, it indicates that the refrigerant is leaking). And ask the combined cold storage engineering personnel to supplement the refrigerant and deal with the leakage. Check whether the sealing of the combined cold storage door is intact and eliminate it. Whether the refrigerator of the combined cold storage works. Whether the parameter setting of the computer controller of the cold storage is correct, and reassemble the cold storage door for installation. Check whether the cooler in the cold storage fails and replace it. Whether there is enough clearance for stacking articles in the warehouse and dredge them.
During the use of the goods yard medical cold storage project, the stored goods must be in strict accordance with the relevant regulations. The goods should have a certain distance from the ground and wall of the cold storage. When stacking, the distance between the goods and the goods must be cm. At the same time the distance between the goods and the cold fan should also be 100 cm. No goods can be stored within this range, This is also an important content in the use of medical cold storage engineering.
The suction pressure of fresh-keeping storehouse remains unchanged, and when the exhaust pressure increases, when the suction pressure decreases, the exhaust temperature also increases. Both cases are caused by the increase of compression ratio of fresh-keeping warehouse. Too high condensation temperature and exhaust temperature of fresh-keeping warehouse are unfavorable to the operation of compressor, which should be prevented. Too high exhaust temperature will dilute the oil and even carbonize and coke which will worsen the compressor conditions of the fresh-keeping warehouse.
The temperature and humidity in the warehouse shall be kept uniform without movement; Try to finish the food in the warehouse at one time.
manufacturer.Reasonable space: the power consumption of the cold storage is calculated according to the cold consumption of the cold storage, which usually includes two parts: the cold consumption during cargo cooling and refrigeration; It is the cooling consumption of the refrigeration room itself and operation management.
Requirements for the cold storage time of the device: the cold storage of the refrigeration system using ammonia as refrigerant shall be supported in the place with low population density around.
The construction structure of structural cold storage can be brick concrete structure or steel structure, which can be determined according to their own budget and actual needs. At present, most cold storages are constructed with single-layer steel structure, and are equipped with combined thermal insulation storage body, unloading platform, system, pipeline system, etc. according to the actual needs of cold storage circulation.
The temperature is too high, the condenser is blocked in the cold storage,Trentay attemptHow much does it cost to install a small cold storage, the compressor is overloaded, there is a lack of refrigerant, the air intake is too large, and the compressor is stuck.
Test conclusion.The common phenomenon of quick freezing storehouse is that the temperature of quick freezing storehouse can't drop down or drops slowly. Now, a simple analysis is made on the reasons for the slow drop of temperature: the cold capacity loss of quick freezing storehouse is large due to poor thermal insulation or sealing performance; the poor thermal insulation performance is due to insufficient thickness of thermal insulation layer of pipeline and warehouse thermal insulation wall, It is mainly caused by improper selection of insulation layer thickness in design or poor quality of insulation materials in construction.
Establish a perfect computer network to realize the scientization of refrigeration supply chain distribution and traceability. In the European Union, the United States and Japan, all members of the food supply chain have the legal responsibility to implement traceability.
Step of cold storage design: selection and laying of cold storage thermal insulation materials. The use of cold storage thermal insulation materials must be adjusted to the time, which not only has excellent fire resistance, but also has high cost performance. There are several types of cold storage insulation materials. One is the plate produced and processed into a fixed shape and specification, with fixed length, total width and thickness. The cold storage plate with relative specification and model can be selected according to the installation of the warehouse body. The high and medium temperature cold storage generally adopts 10cm thick cold storage plate, 12cm or 15cm thick cold storage board is generally used for ultra-low temperature cold storage and freeze-cleaning cold storage; Another kind of cold storage can be sprayed with polyurethane spray paint and polyurethane foam, and the raw materials can be sprayed into the brick or concrete warehouse of the cold storage to be built immediately. After shaping, it is both waterproof and thermal insulation. Thermal insulation materials include polyurethane, polystyrene grease, etc. Polyurethane is non hygroscopic and has good fire resistance but the cost is high; Polystyrene resin has strong water absorption capacity and weak fire resistance, but the cost is low.
Trentay attempt.After being stored in the medical cold storage project, ventilating medical products may also emit some odors. Once these odors are stored in a certain quantity, they will also have a certain impact on other products. Therefore, we must carry out regular ventilation in the process of daily use, so as to effectively reduce the storage time of products. If the medical cold storage project uses row tube refrigeration, the image of frosting may appear after use for a period of time. If we do not defrost in time, it will also affect the effect of. Therefore, I hope you must pay attention to defrosting.
Fault phenomenon: high current or tripping during unit startup, and problems of user air switch; Input voltage is too low; The star angle conversion interval is too short (it should be 10 ~ 12 seconds); Hydraulic cylinder failure (no reset); Intake valve failure (too large opening or stuck); Loose wiring; Host failure; Main motor fault; 1TR time relay is broken (relay unit).
However, long-term continuous operation will inevitably lead to equipment aging, so reasonable maintenance is particularly important.