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Jindong recommended to buy heat transfer oil

  Heat transfer oil is widely used in petroleum, chemical, chemical fiber, building materials, textile printing and dyeing, food processing, medicine and other industries. The market demand for heat transfer oil is increasing, but the heat transfer oil manufacturers are mixed, and the quality of the heat transfer oil produced is uneven. The heat transfer oil that you can use with confidence is the key. Jindong shares the relevant purchasing skills with you. I hope you can help. Heat transfer oil (also known as heat transfer fluid) has a range of physical properties such as viscosity, vapor pressure, boiling range, initial boiling point, flash point, flash point, and flow point. The viscosity index of the heat transfer oil is directly related to the heat transfer effect, and the smaller the viscosity of the heat transfer oil, the faster the flow. Its heat transfer efficiency is higher. The vapor pressure, flash point, and ignition point of the heat transfer oil are related to whether the heat transfer oil is easily volatilized and whether it is easy to catch fire. If the vapor pressure of the oil is small, the flash point, the ignition point and the spontaneous ignition point are high, the oil is not easy to cause. Fire. The initial slip point of the heat transfer oil is related to its safety and the use temperature. The higher the initial boiling point, the better the safety and the higher the use temperature. The flow point of the heat transfer oil is the lowest temperature that guides the flow of the heat transfer oil, and the heat transfer oil having a low flow point maintains the flow state even in the cold north. If the flow point is too high, it will cause difficulty in starting the heat transfer oil furnace and the system. Therefore, the heat transfer oil with low flow point is convenient for use in a cold place.

  (1) Judging the nature of heat transfer oil, usually by testing the following seven indicators:

  1, viscosity

  The viscosity is the degree of thickening and fluidity of the heat transfer oil under specified conditions. When the mechanical load and the rotational speed are the same. The greater the viscosity of the heat transfer oil used, the greater the power loss. Since most of the domestic oil is used in the high temperature heat transfer stage, almost all brands of heat transfer oil have similar viscosities at high temperatures. Generally, the manufacturer changes the viscosity of the heat transfer oil by ±15%, and considers that the indicator is scrapped. When the oxidative polycondensation reaction occurs in the heat carrier, the viscosity increases remarkably. Good viscosity and good pumping performance. The viscosity will increase sharply due to the generation of soluble polymer after cracking due to overheating; when the viscosity increases, the flow point of the heat transfer oil will also increase, and when the heat transfer oil cools, the asphalt will be sticky or solid in the hot oil furnace tube. The furnace tube is blocked, the hot oil pump cannot be rotated, and the hot oil furnace cannot be heated. At this time, cleaning the hot oil furnace requires a lot of manpower and material resources to dredge the hot oil furnace tube, and sometimes the hot oil furnace is scrapped. If there are many light volatiles, the viscosity will decrease, but the vapor pressure will become large and the volatility will be high, which will cause the heat transfer oil pump running at high temperature to generate gas resistance, which makes the transportation difficult.

  2, acid value

  The acid value is the total amount of organic and inorganic acids in the heat transfer oil, that is, the total amount of potassium hydroxide consumed per gram of the heat transfer oil. The organic acid is divided into a low molecular organic acid and a high molecular organic acid, and the low molecular organic acid and the inorganic acid are corrosive to the metal. Especially in the presence of water molecules, corrosion will increase. Most of the heat transfer oil is a high molecular organic acid, and the high molecular organic acid has little corrosion to the equipment. The heat transfer oil has a coking process of inducing, adsorbing, hardening and shedding in high temperature operation. These processes form a layer of heat transfer oil coke in the hot oil furnace pipe, and affect the heat transfer effect of the hot oil furnace, and also isolate the contact between the heat transfer oil and the metal pipe wall, so that these acids can not corrode the equipment, thereby showing the acid The value is not critical to the corrosivity of the metal. The degree of deterioration of the oil can be judged by the acid value. When the high temperature heat carrier is above 60 °C, it is easily oxidized by air or water to form an organic acid. The value of the high temperature heat carrier can determine the difficulty and severity of the high temperature oxidation of the heat carrier.

  3, flash point (opening)

  It is the lowest temperature at which a mixture of vapor and air escaping from the heated oil is in contact with the flame under a specified condition. The higher the flash point, the less likely the fire is, and the safer it is to use, but it cannot be understood that the higher the flash point, the higher the temperature. Different brands of thermal oil have different flash points, with a minimum of 140 ° C and a maximum of 200 ° C. The heat transfer oil is used in a heating oil furnace of a closed system, so that the three elements of combustion are not provided (combustion = fuel + temperature + oxygen), so the heat transfer oil does not burn. If there is a leak in the system, it is also a smoke first. In the case of an open flame, a flashing phenomenon will occur, and it will not burn in time. It can be seen that the flash point of the heat transfer oil is a non-important factor for the heat transfer oil scrapping index. As long as the mastery is good, the heat transfer oil will not burn and the safety of the hot oil furnace will not be affected.

  4, carbon residue

  The residual carbon is a mixture of polycyclic aromatic hydrocarbons, colloids and asphaltenes. It is easily decomposed by dehydration and dehydrogenation condensation under the condition of insufficient air to form residual carbon. The size of the carbon residue can roughly determine the tendency of the heat transfer oil to coke during high temperature use. The heat transfer coefficient of coking is very different from that of metal, and the energy consumption is increased. Therefore, carbon residue is the main factor affecting heat transfer oil.

  5, moisture

  Moisture is an important indicator for the smooth operation of the device. If the water exceeds the standard in the heating medium, it is easy to appear boiling oil during the heating process, and it is easy to accelerate the hydrolysis and oxidation reaction of the oil. Causes the decomposition of the heat transfer oil to fail. The products used in general industrial installations shall not exceed 0.05%. The civil electric heaters cannot exclude water. To ensure safety, the index is set to be no more than 0.02%.

  6, pour point

  The pour point is a quality indicator indicating the low-temperature flow performance of the oil. The significance of this indicator: (1) The amount of paraffin content can be estimated. (2) Guide the ambient temperature.

  7, distillation range

  The distillation range of the heat transfer oil of the distillation range is related to the use temperature of the heat transfer oil. It refers to the range between the lowest boiling point and the highest boiling point of the oil composition. The larger the range, the wider the boiling range and the lowest boiling point in the oil should be considered. The appropriate amount should be used to ensure that the oil is not excessively lost during the process of oiling, and that the viscosity of the oil is not too high to affect the effect and form carbon deposits. The heat transfer oil is within a specified temperature range and the distillation range is narrower.

  In addition, the annual oil analysis of heat transfer oil is very important. After one year of heat transfer oil use, oil analysis should be carried out. If there is no problem, it can be used continuously. If the quality index reaches the scrapping index, it should be replaced with new oil. In addition, it is found that the heat transfer effect of the heat transfer oil is poor or other abnormal conditions occur during use, and oil analysis is also required in time. If the residual carbon is not more than 1.5%, the acid value is not more than 0.5 mgKOH/g, and the flash point change is not more than 20%. If the viscosity changes by no more than 15%, it can be used continuously. If one item does not meet the standard, the owner should consider adding some new oil or replacing all new oil. In general, high-quality heat transfer oils have a long service life and do not require frequent replacement of heat transfer oil. Safety production is the biggest saving; the use of heat transfer oil for over-temperature will greatly reduce the service life of the heat-conducting oil. Therefore, it is necessary to extend the service life of the heat-conducting oil. It is necessary to control the temperature during use, and the maximum allowable use of each heat-conducting oil. The temperature is not the same, the owner should pay special attention during the use. For example, Jindong hydrogenated terphenyl heat transfer oil 350 ° C, the maximum allowable temperature for use by the owner is 345 ° C.

  (2) The quality indicators of the heat transfer oil testing in Shedong County are in full compliance with the following requirements:

  1. The thermal conductivity oil has large thermal conductivity, high specific heat, high thermal efficiency and good economic benefits.

  2. The heat transfer oil provides good thermal stability and oxidation stability at the maximum allowable temperature, and has a long service life.

  3. It has a high flash point, spontaneous ignition point and boiling point. The flash point of the heat transfer oil and the high self-ignition point can avoid the risk of fire. The heat transfer oil used in the liquid phase, the higher boiling point (initial boiling point) and the lower content of low boiling point can ensure the heat transfer oil in the liquid. Safe use in phase.

  4. The heat transfer oil has a low acid value and residual carbon, and does not cause chemical reaction and corrosion to the materials of the equipment and pipelines in the system. The heat transfer oil is used under high temperature conditions and is operated for a long time in the heat transfer oil heating system. If it chemically reacts or corrodes the material and equipment of the system or does not detect the heat transfer oil, it will cause the equipment and pipeline to be scrapped in advance.

  The acid value is the sum of the organic acids in the heat transfer oil. The acid value is high, and when there is a trace amount of water in the oil, it will cause corrosion to the equipment.

  The charcoal is a colloidal or asphaltene formed after polymerization (or condensation) of the heat-transfer oil cracking product, and is a carbonaceous substance formed after being heated. The high carbon residue will cause coking, affecting the heat transfer effect, and block the equipment and pipeline when it is serious.

  5. Viscosity and freezing point are low. Viscosity indicates the degree of thickening and fluidity of the heat transfer oil at a certain temperature. The viscosity is large, the internal friction is large, the conveying capacity of the hot oil pump is also poor, and at the same time, the viscosity is large, and the heat transfer effect is also lowered; the freezing point indicates the physical and chemical properties of the heat transfer oil at a low temperature. The freezing point is low, and the hot oil equipment located in the cold area of ​​the north can still start normally.

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