Precision Oven

• Flame-retardant PP Materials in Industry Working Principle

  Oct 27, 2025

  Polypropylene (PP) itself is a highly flammable hydrocarbon with a limiting oxygen index (LOI) of only 17.8%. It will continue to burn even after being removed from the fire source. The core principle of flame-retardant PP is to interrupt or delay its combustion cycle through physical and chemical means. Combustion requires the simultaneous existence of three elements: combustible material, heat and oxygen. The function of flame retardants is to destroy this "burning triangle".   In industry, flame retardancy is mainly achieved by adding flame retardants to PP. Different types of flame retardants function through the following mechanisms: 1. Gas-phase flame retardant mechanism This is one of the most common mechanisms, especially applicable to traditional halogen-based flame retardants. When flame retardants are heated and decomposed, they can capture the free radicals (such as H· and HO·) that maintain the combustion chain reaction in the combustion reaction zone (flame), causing their concentrations to drop sharply and thus interrupting the combustion. 2. Condensed phase flame retardant mechanism This is the most mainstream mechanism of halogen-free flame-retardant PP. Flame retardants promote the formation of a uniform and dense carbon layer on the surface of polymers. This layer of carbon has three major functions. The first step is to prevent external heat from entering the interior of the polymer. Secondly, it prevents the escape of flammable gases inside and the entry of external oxygen. Finally, it inhibits the further pyrolysis of the polymer and the generation of smoke. When a fire occurs, the acid source promotes the dehydration, cross-linking and carbonization of the carbon source. Meanwhile, the large amount of gas produced by the decomposition of the gas source causes the softened carbon layer to expand, eventually forming a porous, dense and strong foam carbon layer, which protects the underlying PP like "armor". 3. Cooling/heat absorption mechanism Flame retardants absorb a large amount of heat during the decomposition process, reducing the surface temperature of polymers and making it difficult for them to continuously pyrolyze and produce flammable gases. Typical representatives include aluminium hydroxide (ATH) and magnesium hydroxide (MH). When they decompose, they absorb a large amount of heat (endothermic reaction) and release water vapor. The water vapor can not only dilute flammable gases but also play a cooling role. 4. Dilution mechanism Flame retardants decompose to produce a large amount of non-flammable gases (such as water vapor and CO₂, etc.), which can dilute the concentration of flammable gases and oxygen near the polymer surface, making combustion unsustainable. Both the gas sources of metal hydroxides and intumescent flame retardants have this function.   In conclusion, the working principle of flame-retardant PP in industry is a complex process involving the synergy of multiple mechanisms. Modern flame-retardant PP technology is developing towards halogen-free, low smoke, low toxicity and high efficiency. Among them, the condensed phase flame-retardant mechanism represented by intumescent flame retardants (IFR) is the core of current research and application. By carefully designing flame-retardant formulas, the best balance can be achieved among flame-retardant efficiency, material mechanical properties, processing performance and cost.

  hot Tags : High Temperature Oven High Temperature Test Chamber Low Temperature Test Chamber Programmable Temperature Test Chamber Temperature Testing Equipment Precision Oven

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• Customized Solution for Double-Door Temperature Test Equipment

  Oct 25, 2025

  1.Core customization requirement analysis 1.1 The standard box size or load-bearing capacity (such as automotive parts, large unmanned aerial vehicles, and entire cabinet servers) cannot meet the requirements. Special sample racks, trays or suspension devices are required. The test samples need to be powered on and run inside the box, and connected to cables or pipes (such as battery pack charge and discharge tests, engine component tests). Oil stains, particulate matter or corrosive gases may be released during the sample testing process. 1.2 It needs to be connected with mechanical arms and AGV carts to achieve automatic loading and unloading. The heating and cooling rates required far exceed the standard specifications (such as >15°C/min). 1.3 The equipment needs to adapt to specific room sizes, door opening sizes or floor heights. There are special requirements for the power supply (if it cannot meet 380V) and the cooling water source (if a cooling tower cannot be provided).   2. Key customized technical specifications 2.1 Customized Dimensions The internal effective space is determined entirely based on the size and quantity of the customer's samples. The minimum distance between the sample and the box wall needs to be considered to ensure uniform airflow. It is necessary to clearly define the size of the door, the material of the sealing strip, the door lock mechanism (mechanical lock, pneumatic auxiliary lock), and the size and quantity of the observation window. The inner box is usually made of SUS304 stainless steel. The outer box body can be made of high-quality steel plate with plastic spraying or SUS304. For corrosive tests, more durable materials should be specified. Test holes are used for leads. The size, quantity and position of the hole diameters (such as left or right) need to be customized, and sealing plugs or flanges should be provided. 2.2 Confirm the test interval The technical index standards for temperature are usually from -70°C to +150°C. The standard heating and cooling rate is 1 to 3°C/min. Linear rapid temperature change: 5 to 10°C/min. Nonlinear rapid temperature change: Customizable to 15°C/min or even higher. This is directly related to the power configuration of the refrigeration and heating systems and is a key factor influencing the cost. Customize stricter control accuracy, such as uniformity ≤±1.0°C and fluctuation ≤±0.5°C. 2.3 Refrigeration System Air cooling: Suitable for sites where the ambient temperature is not high and the ventilation around the equipment is good. Water cooling: It is suitable for large cooling capacity, high heat generation samples, or situations with high ambient temperatures. It is more efficient but requires a cooling tower. Cascade refrigeration: It is used for low-temperature requirements below -40°C and usually adopts two-stage cascade. 2.4 Installation Method The refrigeration system of the integrated machine is located at the top or bottom of the box, with a compact structure and convenient installation. The split-type refrigeration unit is separated from the box body and is suitable for high-power equipment. It can discharge noise and heat to the outside, but the installation is complex. 2.5 Control System and Software The controller customizes the size and brand of the color touch screen, supports multi-segment programming, program group loops, step jumps, etc. Customized LAN interface for connecting to the upper computer (computer) for data monitoring and recording. Whether it is necessary to support remote network monitoring and operation, as well as customize record intervals and storage capacity. 2.6 Independent sample over-temperature protector. Compressor overheat, overcurrent and overpressure protection; Fan overcurrent protection Cooling water cut-off protection and automatic stop test function when the door is opened; Leakage or short-circuit protection; Sound and light alarm prompt.   Customizing double-door temperature test equipment is a systematic project. The key to success lies in the clarification and refinement of the initial requirements. A detailed and unambiguous "Technical Requirements Document" serves as the cornerstone for communication between equipment suppliers and customers. It ensures that the final delivered equipment fully complies with testing, process, and site requirements, avoiding subsequent disputes and cost overruns.

  hot Tags : Industrial Oven Vacuum Oven Precision Oven Smart Oven High-temperature Testing Equipmen Environmental Reliability Testing

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• Lab Aging Test Chamber Working Principle

  Oct 17, 2025

  Many products (such as rubber, plastic, insulating materials, electronic components, etc.) will age due to the combined effects of heat and oxygen when exposed to the natural environment over a long period of use, such as becoming hard, brittle, cracking, and experiencing a decline in performance. This process is very slow in its natural state. The air-exchange aging test chamber greatly accelerates the aging process by creating a continuously high-temperature environment and constantly replenishing fresh air in the laboratory, thereby evaluating the long-term heat aging resistance of materials in a short period of time.   The working principle of Lab aging test chamber mainly relies on the collaborative efforts of three systems: 1. The heating system provides and maintains a high-temperature environment inside the test chamber. High-performance electric heaters are usually adopted and installed at the bottom, back or in the air duct of the test chamber. After the controller sets the target temperature (for example, 150°C), the heater starts to work. The air is blown through the heater by a high-power fan. The heated air is forced to circulate inside the box, causing the temperature inside the box to rise evenly and remain at the set value. 2. The ventilation system is the key that distinguishes it from ordinary ovens. At high temperatures, the sample will undergo an oxidation reaction with oxygen in the air, consuming oxygen and generating volatile products. If the air is not exchanged, the oxygen concentration inside the box will decrease, the reaction will slow down, and it may even be surrounded by the products of the sample's own decomposition. This is inconsistent with the actual usage of the product in a naturally ventilated environment. 3. The control system precisely controls the parameters of the entire testing process. The PID (Proportional-integral-Derivative) intelligent control mode is adopted. The real-time temperature is fed back through the temperature sensor inside the box (such as platinum resistance PT100). The controller precisely adjusts the output power of the heater to ensure that the temperature fluctuation is extremely small and remains stable at the set value. Set the air exchange volume within a unit of time (for example, 50 air changes per hour). This is one of the core parameters of the air-exchange aging test chamber, which usually follows relevant test standards (such as GB/T, ASTM, IEC, etc.).   The test chamber creates a high-temperature environment through electric heaters, achieves uniform temperature inside the box by using centrifugal fans, and continuously expels exhaust gases and draws in fresh air through a unique ventilation system. Thus, under controllable experimental conditions, it simulates and accelerates the aging process of materials in a naturally ventilated thermal and oxygen environment. The biggest difference between it and a common oven lies in its "ventilation" function, which enables its test results to more truly reflect the heat aging resistance of the material during long-term use.

  hot Tags : Temperature Test Chamber Aging Test Chamber Precision Oven Drying Test Chamber Weathering Test Chamber Aging Test Equipment

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• Lab Thermal Resistance Sensing Core Working Principle

  Oct 16, 2025

  The core of the thermal resistance induction in high and low temperature test chambers also utilizes the physical property that the resistance value of platinum metal changes with temperature. The core logic of the control system is a closed-loop feedback control: measurement → comparison → regulation → stability   Firstly, the thermal resistance sensor senses the current temperature inside the chamber and converts it into a resistance value. The measurement circuit then converts the resistance value into a temperature signal and transmits it to the controller of the test chamber. The controller compares this measured temperature with the target temperature set by the user and calculates the deviation value. Subsequently, the controller outputs instructions to the actuator (such as the heater, compressor, liquid nitrogen valve, etc.) based on the magnitude and direction of the deviation. If the measured temperature is lower than the target temperature, start the heater to heat up; otherwise, start the refrigeration system to cool down. Through such continuous measurement, comparison and adjustment, the temperature inside the box is eventually stabilized at the target temperature set by the user and the required accuracy is maintained.   Due to the fact that high and low temperature test chambers need to simulate extreme and rapidly changing temperature environments (such as cycles from -70°C to +150°C), the requirements for thermal resistance sensors are much higher than those for ordinary industrial temperature measurement.   Meanwhile, there is usually more than one sensor inside the high and low temperature test chamber. The main control sensor is usually installed in the working space of the test chamber, close to the air outlet or at a representative position. It is the core of temperature control. The controller decides on heating or cooling based on its readings to ensure that the temperature in the working area meets the requirements of the test program. The monitoring sensors may be installed at other positions inside the box to verify with the main control sensors, thereby enhancing the reliability of the system. Over-temperature protection is independent of the main control system. When the main control system fails and the temperature exceeds the safety upper limit (or lower limit), the monitoring sensor will trigger an independent over-temperature protection circuit, immediately cutting off the heating (or cooling) power supply to protect the test samples and equipment safety. This is a crucial safety function.   Lab thermal resistance sensor is a precision component that integrates high-precision measurement, robust packaging, and system safety monitoring. It serves as the foundation and "sensory organ" for the entire test chamber to achieve precise and reliable temperature field control.

  hot Tags : High Temperature Test Chamber Low Temperature Test Chamber Thermal Shock Test Chamber Programmable Temperature Test Chamber Precision Oven Intelligent Testing Instruments

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• Lab Dust Free Oven Environmental Test Condition

  Oct 11, 2025

  Internal environmental conditions Benchmark cleanliness: At the beginning of the test, the chamber must reach the highest cleanliness level it claims (such as ISO Class 5 / Class 100). This is the premise of all tests. Before the test, the oven needs to run a long period of "self-cleaning" until the particle count shows that the concentration is stable below the standard for multiple consecutive times. Temperature and Humidity: Although the oven is a heating device, its initial state needs to be clearly defined. The initial environment for testing is usually normal temperature and humidity, for example, a temperature of 20±5°C and a relative humidity of 30-60% RH. This is crucial for testing the heating time and temperature uniformity. If the process has requirements for the dew point of the environment, it may be necessary to record the initial absolute humidity. Airflow state: The test should be conducted under the specified airflow pattern, typically in a vertical or horizontal laminar flow state. The fan must operate at the rated speed, with stable air pressure and air volume. Test load: The test is divided into two conditions: no-load and full-load. No-load is the benchmark test for equipment performance. Fill the effective working space with a fully loaded simulated load (such as metal, pallets, etc.) to simulate the harshest working conditions. Full-load testing can truly reflect the impact of products on air flow and temperature fields in actual production.   External environmental conditions 1. The cleanliness level of the external environment must be lower than or equal to the cleanliness level designed by the oven itself. For instance, when testing an oven of Class 100, it is best to do it in a room of Class 1000 or cleaner. If the external environment is too dirty, it will seriously interfere with the measurement results of the internal cleanliness of the oven when opening and closing the door or when water seeps through gaps. 2. The laboratory requires a stable temperature and humidity environment. It is generally recommended to conduct the test under standard laboratory conditions, such as 23±2°C and 50±10% RH. Avoid testing in extreme or highly volatile environments. 3. The test area should be free of strong convective winds and it is best to maintain a slight positive pressure to prevent external contaminants from entering the test area. 4. The power supply voltage and frequency should be stable within the range required by the equipment. 5. The equipment should be placed on a ground or base with less vibration. There are no large stamping equipment, fans or other strong vibration sources around.   When testing a dust-free oven, controlling the external environment is as important as measuring the internal environment. An unstable, dirty or strongly interfering external environment can lead to distorted test data and fail to truly reflect the performance of the equipment. All test conditions should be clearly recorded in the final verification report to ensure the traceability and repeatability of the tests.

  hot Tags : Industrial Oven Environmental Testing Equipment Precision Oven Dust Free Oven Clean Oven Industrial Clean Oven

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• Building a Safe Test Chamber Test Environment

  Sep 16, 2025

  The key to creating a safe testing environment for the Lab high and low temperature test chamber lies in ensuring personal safety, equipment safety, test piece safety and data accuracy. 1.Personal Safety Considerations Before opening the high-temperature chamber door to take out the sample, it is necessary to wear the high and low temperature resistant protective equipment properly. When performing operations that may cause splashing or the leakage of extremely hot/cold gases, it is recommended to wear a protective face mask or goggles. The test chamber should be installed in a well-ventilated laboratory and avoid operating in a confined small space. High-temperature testing may release volatile substances from the test piece. Good ventilation can prevent the accumulation of harmful gases. Ensure that the power cord specifications meet the equipment requirements and the grounding wire must be reliably connected. Most importantly, it is strictly forbidden to touch power plugs, switches and samples with wet hands to prevent electric shock.   2. Install the equipment correctly The minimum safety distance specified by the manufacturer (usually at least 50-100 centimeters) must be left on the back, top and both sides of the equipment to ensure the normal operation of the condenser, compressor and other heat dissipation systems. Poor ventilation can cause equipment to overheat, performance decline and even fire. It is recommended to provide a dedicated power line for the test chamber to avoid sharing the same circuit with other high-power equipment (such as air conditioners and large instruments), which may cause voltage fluctuations or tripping. The ambient temperature for the operation of the equipment is recommended to be between 5°C and 30°C. Excessively high ambient temperatures will significantly increase the load on the compressor, leading to a decline in refrigeration efficiency and malfunctions. Please note that the equipment should not be installed in direct sunlight, near heat sources or in places with strong vibrations.   3. Ensuring the Validity and Repeatability of Tests The samples should be placed in the central position of the working chamber inside the box. There should be sufficient space between the samples and between the samples and the box wall (it is usually recommended to be more than 50mm) to ensure smooth air circulation inside the box and uniform and stable temperature. After conducting high-temperature and high-humidity tests (such as in a constant temperature and humidity chamber), if low-temperature tests are required, dehumidification operations should be carried out to prevent excessive ice formation inside the chamber, which could affect the performance of the equipment. It is strictly prohibited to test flammable, explosive, highly corrosive and highly volatile substances, except for explosion-proof test chambers specially designed for this purpose. It is strictly prohibited to place dangerous goods such as alcohol and gasoline in ordinary high and low temperature chambers.   4. Safety Operation Specifications and Emergency Procedures Before operation, check whether the box door is well sealed and whether the door lock function is normal. Check if the box is clean and free of any foreign objects. Confirm whether the set temperature curve (program) is correct. During the test period, it is necessary to regularly check whether the operation status of the equipment is normal and whether there are any abnormal noises or alarms. Sample handling and placement norms: Wear high and low temperature gloves properly. After opening the door, slightly turn your body to the side to avoid the heat wave hitting your face. Quickly and carefully remove the sample and place it in a safe area. Emergency response: Be familiar with the location of the emergency stop button of the equipment or how to quickly cut off the main power supply in an emergency. Carbon dioxide fire extinguishers (suitable for electrical fires) should be provided nearby instead of water or foam fire extinguishers.

  hot Tags : Constant Temperature and Humidity Test Chamber High and Low Temperature Test Chamber Temperature Cycling Box Test Chamber Test Environment Precision Oven Safety Precautions for Test Chambers

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