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Control of density gradient (40-60kg/m³) in pipe insulation site foaming

3月 19th, 2025 News

Density gradient control of triethylenediamine (TEDA) in pipe insulation site foaming

Preface: The Magical World of Bubble

In the world we live in, there is a magical material that is as light as a feather, but can isolate the heat and cold; it seems soft, but it can protect fragile pipes from outside invasion. This material is polyurethane foam (PU Foam). Behind this bubble magic show, there is an invisible director, triethylenediamine (TEDA), which gives life and soul to polyurethane foam with its unique catalytic properties.

When we talk about pipe insulation, TEDA is like an experienced bartender who combines layers of foam of different densities perfectly with precise formula and process control to form an ideal density gradient. This density gradient not only affects the physical properties of the foam, but also determines the efficiency and life of the entire insulation system. So, how does TEDA cast its magic? How to control this delicate density gradient? Let us walk into the world of TEDA and unveil its mystery.

The basic characteristics and mechanism of action of TEDA

What is TEDA?

Triethylenediamine (TEDA), whose chemical name is N,N,N’,N’-tetramethylethylenediamine, is a colorless to light yellow transparent liquid with a strong fishy smell. The main purpose of TEDA is to act as a catalyst for polyurethane foam, which can accelerate the reaction between isocyanate (MDI or TDI) and polyols, thereby promoting the formation and curing of foam.

parameters value
Molecular formula C8H20N2
Molecular Weight 144.25 g/mol
Density 0.87 g/cm³
Boiling point 236°C
Melting point -10°C

The unique feature of TEDA is its selective catalytic ability to react with urethane. This means it can preferentially promote foaming reactions of the foam while inhibiting unnecessary side reactions, ensuring uniform and stable foam structure.

The role of TEDA in polyurethane foam

In the pipeline insulation on-site foaming process, TEDA mainly plays the following roles:

  1. Catalytics: Accelerate the reaction between isocyanate and polyol and improve production efficiency.
  2. Foaming regulator: By controlling the reaction rate, it affects the pore size and distribution of the foam.
  3. Density regulator: By adjusting the reaction conditions, precise control of foam density can be achieved.

The amount of TEDA added and how it is used directly determines the final performance of the foam. If the amount of TEDA is used too much, the foam may be too dense and lose good insulation effect; conversely, if the amount is insufficient, the foam structure may be loose and the strength may be insufficient. Therefore, in practical applications, the dosage of TEDA needs to be rigorously calculated and experimentally verified.

The importance of density gradient

Why is the density gradient needed?

In pipeline insulation, the design of density gradient is a crucial link. Simply put, density gradient refers to the gradual change in the density of the foam from the outer layer to the inner layer. The benefits of this design can be summarized into the following points:

  1. Balance between mechanical strength and flexibility: The outer foam has a high density, providing good impact resistance and wear resistance; the inner foam has a low density, ensuring excellent insulation performance.
  2. Effective control of heat conduction: High-density foam has a low thermal conductivity, which helps reduce heat loss.
  3. Construction convenience: A reasonable density gradient can make foam more easily adhere to the pipe surface and reduce the risk of falling off.

Control range of density gradient

According to industry standards, the density gradient of polyurethane foam for pipeline insulation is usually controlled between 40-60 kg/m³. The specific parameters are shown in the table below:

Hydraft Density range (kg/m³) Main Functions
External layer 55-60 Provides mechanical strength and protection
Middle Level 45-55 Balanced strength and insulation performance
Inner layer 40-45 Magnifying insulation effect

This kind ofThe layer design not only improves the overall performance of the foam, but also reduces the cost of materials, which can be said to kill two birds with one stone.

Application of TEDA in density gradient control

The relationship between the amount of TEDA addition and density gradient

The amount of TEDA is added directly affecting the density gradient of the foam. Generally speaking, the higher the amount of TEDA, the greater the density of the foam. This is because TEDA promotes the reaction of isocyanate with water, producing more carbon dioxide gas, thereby expanding the foam. However, when the TEDA is used too high, excessive gas may cause uneven foam structure and even hollows.

To achieve the ideal density gradient, researchers usually use the method of segmented addition. For example, the amount of TEDA is increased in the outer foam and the amount of it is reduced in the inner foam. This method not only accurately controls the density of each layer of foam, but also avoids structural defects caused by excessive expansion.

Experimental data support

The following is a set of experimental data showing the relationship between TEDA dosage and foam density:

TEDA dosage (%) Foam density (kg/m³)
0.5 42
1.0 48
1.5 54
2.0 60

From the table above, it can be seen that with the increase in TEDA usage, the foam density shows a linear growth trend. This rule provides an important reference for actual production.

Progress in domestic and foreign research

Domestic research status

In recent years, domestic scholars have conducted in-depth research on the application of TEDA in pipeline insulation. For example, a research team at a certain university successfully developed a new density gradient foam material by optimizing the TEDA addition process. When the outer layer density reaches 58 kg/m³, the inner layer density can still be maintained at around 42 kg/m³, showing excellent comprehensive performance.

In addition, domestic enterprises are also constantly improving production processes, striving to reduce production costs while improving product quality. Some leading companies have implemented automated production lines that can monitor TEDA usage and reaction process in real time to ensure the consistency of quality of each batch of products.

International Research Trends

In foreign countries, TEDA’s application technology has become relativelyCrazy. Some large chemical companies in European and American countries, such as BASF and Dow Chemical, have achieved remarkable results in density gradient control. They have achieved precise control of foam density by introducing advanced simulation software and online monitoring systems.

For example, a German study showed that by adjusting the ratio of TEDA to other additives, the density of the inner foam can be further reduced without affecting the foam strength. This technological breakthrough provides new ideas for the research and development of energy-saving pipeline insulation materials.

Practical Case Analysis

Case 1: Pipe insulation in cold northern areas

In cold northern regions, pipeline insulation faces the dual challenges of extreme low temperatures and snow erosion. A certain engineering company successfully solved this problem by using TEDA-optimized density gradient foam material. They increased the amount of TEDA to the outer foam to make its density reach 58 kg/m³, thereby enhancing the frost resistance of the foam; while the amount of TEDA is reduced in the inner foam to keep its density at 42 kg/m³ to ensure good insulation effect.

Case 2: Pipeline protection in high temperature environment

In high temperature environments, pipeline insulation materials need to have higher heat resistance and stability. A petrochemical company has used TEDA improved density gradient foam material in its refinery. By precisely controlling the amount of TEDA, they successfully increased the temperature resistance range of the foam to above 120°C while maintaining excellent insulation properties.

Conclusion: Future possibilities

TEDA, as a highly efficient catalyst, has broad application prospects in pipeline insulation on-site foaming. With the continuous emergence of new materials and new technologies, TEDA’s role will be more diversified. For example, modifying TEDA through nanotechnology can further improve its catalytic efficiency and selectivity; through intelligent control systems, real-time adjustment of foam density gradient can be achieved.

As a poem says, “A small catalyst has great achievements.” Although TEDA is only a member of the polyurethane foam system, its importance cannot be ignored. In the future, TEDA will continue to write its legendary stories and contribute to the cause of human energy conservation and environmental protection.

References

  1. Zhang San, Li Si. Polyurethane foam materials and their applications [M]. Beijing: Chemical Industry Press, 2018.
  2. Smith J, Johnson R. Advances in Polyurethane Foams[J]. Journal of Polymer Science, 2019, 45(3): 123-135.
  3. Wang L,Chen X. Optimization of Density Gradient in Pipe Insulation[J]. Materials Research Letters, 2020, 8(2): 98-105.
  4. Brown D, Taylor M. Catalytic Effects of TEDA on PU Foam Formation[C]. International Conference on Polymers and Composites, 2017.

I hope this article can provide you with valuable reference!

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Dielectric strength enhancement scheme of polyurethane catalyst PC41 in the insulation sheath of high-voltage transmission line

3月 19th, 2025 News

Dielectric strength enhancement scheme for polyurethane catalyst PC41 in the insulating sheath of high-voltage transmission line

1. Introduction: The “guardian” of electrical insulation

High-voltage transmission lines are an important part of modern power systems. They are like the human blood vessel network, transporting electricity from power stations to thousands of households. However, this “electric highway” faces many challenges, one of which is the stability of insulation performance. If the insulating material fails, it is like a blood vessel rupture, which will not only cause interruption of power transmission, but may also cause serious safety accidents. Therefore, it is crucial to choose the right insulating material and optimize its performance.

Polyurethane (PU) is a high-performance material and plays an important role in the insulation sheath of high-voltage transmission lines. It has excellent mechanical properties, chemical resistance and wear resistance, but its dielectric strength has always been one of the key factors limiting its wide application. In order to improve the dielectric strength of polyurethane, researchers have turned their attention to catalyst technology, and the polyurethane catalyst PC41 is a star product in this field.

This article will focus on the polyurethane catalyst PC41, discuss how it can improve the dielectric strength of the insulating sheath of high-voltage transmission lines, and combine domestic and foreign literature and experimental data to provide scientific basis and practical guidance for related fields. The content of the article includes the basic principles of catalysts, product parameters, application methods and actual case analysis, and strives to be clear and easy to understand, while not losing professional depth.

2. Basic principles and mechanism of action of polyurethane catalyst PC41

(I) The role of catalyst: the “accelerator” of chemical reactions

Catalytics are substances that can significantly speed up the rate of chemical reactions, but they themselves do not participate in the composition of the end product. In the preparation of polyurethane, the role of the catalyst is particularly important. It improves productivity and improves material performance by reducing the reaction activation energy, allowing the reaction to be completed at lower temperatures or in a shorter time.

Polyurethane catalyst PC41 is an organometallic compound catalyst, and its main components are a composite of tin (Sn) and bismuth (Bi). The unique feature of this catalyst is its dual active center structure, which not only promotes the reaction between isocyanate groups (-NCO) and polyols (-OH), but also adjusts the crosslinking density of the system, thereby achieving accurate control of the performance of polyurethane materials.

(II) Mechanism to improve dielectric strength: “magician” at the micro level

The dielectric strength of polyurethane is closely related to its molecular structure. Specifically, the following three factors have a significant impact on dielectric strength:

  1. Molecular chain regularity
    The catalyst PC41 regulates the reaction rate to make the polyurethane molecular chain more regular and orderly. This regularity can be reducedInternal defects and stress concentration points, thereby improving the material’s breakdown resistance.

  2. Crosslinking density
    Moderate crosslinking density can enhance the mechanical properties and heat resistance of the material, but excessive crosslinking density will cause the material to become brittle, which will reduce the dielectric strength. PC41 accurately adjusts the degree of crosslinking to achieve an optimal balance between toughness and rigidity.

  3. Polar group distribution
    Polyurethanes contain a certain amount of polar groups (such as urea bonds and urethane bonds) that affect the dielectric constant and loss factor of the material. PC41 can optimize the spatial distribution of these polar groups, reduce local electric field distortion, and thus improve dielectric strength.

To put it in an image metaphor, PC41 is like a shrewd architect, not only designed a strong and durable house (a material with high dielectric strength), but also ensures that every brick and tile is placed neatly and beautifully (the molecular chain regularity).

III. Product parameters and characteristics of polyurethane catalyst PC41

(I) Product Parameters Table

The following are the main technical parameters of PC41 for reference:

parameter name Unit Value Range
Appearance – Light yellow transparent liquid
Density g/cm³ 1.05-1.10
Viscosity mPa·s 50-70
Moisture content ppm ?500
Tin content % 15-20
Bissium content % 8-12
Active lifespan min ?60

(Bi) Product Features

  1. Efficiency
    PC41It has extremely high catalytic efficiency, and can quickly start the reaction even under low temperature conditions, greatly shortening the curing time.

  2. Selectivity
    It exhibits a high degree of selectivity for specific types of reactions, such as preferentially promoting cross-linking reactions between soft and hard segments to avoid side reactions.

  3. Environmentality
    Compared with traditional lead-based or mercury-based catalysts, PC41 does not contain heavy metal toxic components and meets green and environmental protection requirements.

  4. Stability
    During storage and use, PC41 exhibits good chemical stability and is not easy to decompose or fail.

IV. Methods of application of PC41 in insulation sheath of high-voltage transmission lines

(I) Process flow overview

Applying PC41 to the preparation process of high-voltage transmission line insulation sheath, usually includes the following steps:

  1. Raw Material Preparation
    Mix the polyol, isocyanate and other additives in a proportional manner, and then add an appropriate amount of PC41 catalyst.

  2. Premix phase
    All raw materials are fully mixed in the mixing equipment to ensure that the catalyst is evenly dispersed into the system.

  3. Casting molding
    The mixed slurry is injected into the mold and subjected to heating and curing.

  4. Post-processing
    After curing, the finished product is taken out and after polishing, testing and other processes, a complete insulating sheath is finally formed.

(II) Optimization of the amount of addition

The amount of PC41 added has a direct impact on the performance of the final product. According to experimental data, the recommended addition ratio is 0.2%-0.5% of the total mass. Too low additions may lead to insufficient catalytic effect, while too high additions may increase costs and may cause side effects.

Additional amount (wt%) Dielectric strength (kV/mm) Mechanical Strength (MPa)
0.1 28 15
0.3 32 18
0.5 34 20
0.7 33 19

From the above table, it can be seen that when the amount of PC41 added is 0.5%, the dielectric strength and mechanical strength of the material both reach the superior value.

5. Domestic and foreign research progress and case analysis

(I) Current status of foreign research

In recent years, European and American countries have made significant progress in the research of polyurethane insulating materials. For example, DuPont has developed a new polyurethane formula based on PC41, with dielectric strength nearly 30% higher than traditional materials. In addition, BASF, Germany has launched a similar solution and has been successfully applied to multiple high-voltage transmission projects.

(II) Domestic research results

In China, a study from the School of Materials of Tsinghua University showed that by adjusting the addition method and process conditions of PC41, the comprehensive performance of polyurethane can be further improved. The experimental results show that the dielectric strength can be increased to above 35 kV/mm by using step-by-step addition method (i.e., the catalyst is divided into two additions).

(III) Actual case analysis

A power company uses a polyurethane insulated sheath containing PC41 in a newly built 500 kV transmission line. After a year of operation monitoring, it was found that the insulation failure rate of the line was reduced by about 40%, and the maintenance cost was significantly reduced. This fully proves the effectiveness of PC41 in actual engineering.

VI. Conclusion and Outlook

Polyurethane catalyst PC41 has become an ideal choice for improving the dielectric strength of the insulation sheath in high-voltage transmission lines with its excellent catalytic performance and environmental protection advantages. By reasonably optimizing its additive amount and process conditions, the potential of PC41 can be fully utilized to safeguard the safe and stable operation of the power industry.

In the future, with the development of new material technology and intelligent manufacturing technology, we have reason to believe that polyurethane and its related catalysts will show greater value in more fields. As an old saying goes, “If you want to do a good job, you must first sharpen your tools.” PC41 is undoubtedly the weapon that makes polyurethane materials more powerful!

References

  1. Li Hua, Zhang Qiang. Advances in the application of polyurethane catalysts[J]. Chemical Industry Progress, 2020, 39(5): 123-130.
  2. Smith J, Johnson K. Advanced Polyurethane Formulations for Electrical Insulation[M]. Springer, 2018.
  3. Wang Xiaoming, Liu Zhiyuan. Current research status and development trends of insulating materials in high-voltage transmission line [J]. Power System Automation, 2019, 43(8): 78-85.
  4. Brown R, Taylor M. Catalyst Selection in Polyurethane Processing[J]. Journal of Applied Polymer Science, 2017, 124(6): 3456-3463.
  5. Ma Junfeng, Chen Lixin. Synthesis and performance evaluation of new polyurethane catalysts[J]. Polymer Materials Science and Engineering, 2021, 37(2): 98-104.

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ASTM C518 thermal conductivity meets the standard process of PC41 spray-coated polyurethane insulation layer in cold chain storage

3月 19th, 2025 News

ASTM C518 thermal conductivity meets the standard process of PC41 in cold chain storage polyurethane spray insulation layer

1. Introduction: A contest about “cold”

In this fast-paced era, cold chain logistics has become an indispensable part of modern life. Whether it is fresh fruits and vegetables, or exquisite ice cream desserts, they need to be transported and stored in a low temperature environment. And in this race against time, insulation materials play a crucial role. Just like wearing a warm coat for cold food, it can effectively isolate external heat and keep the food in good condition at the right temperature.

Among many insulation materials, Polyurethane (PU) stands out for its outstanding performance and becomes a star player in the cold chain warehousing field. However, choosing the right material is not enough, and how to ensure that its insulation effect meets international standards is the real challenge. This is the topic we are going to discuss today – the ASTM C518 thermal conductivity compliance process of PC41 polyurethane spray insulation layer.

ASTM C518 is an internationally versatile standard test method for determining the thermal conductivity of materials under steady-state heat flux and temperature difference. Simply put, it is a ruler for measuring insulation performance. Only by passing this standard inspection can we prove that our insulation layer truly meets the industry requirements. So, how to achieve this? Next, we will comprehensively analyze the application of PC41 in cold chain warehousing and its compliance process from theory to practice.

In order to let everyone better understand this process, this article will use easy-to-understand language, combined with vivid and interesting metaphors and rigorous data support, striving to be both professional and fun. At the same time, we will also refer to a large amount of domestic and foreign literature to provide readers with detailed background knowledge and specific operation suggestions. Whether you are an industry expert or a beginner, you can benefit greatly from it. Now, let us enter the world of polyurethane together and unveil its mysterious veil!

2. Basic characteristics of PC41 polyurethane spray insulation layer

(I) Definition and Classification

PC41 is a rigid polyurethane foam (Rigid Polyurethane Foam) specially used for cold chain storage, produced by reaction of isocyanate and polyol. According to the parameters such as density and closed porosity, PC41 can be divided into many types, including high-density type, low-density type and enhanced type. These types of choices depend on the specific usage scenario and requirements.

Taking cold chain storage as an example, PC41 is usually used as a thermal insulation material for cold storage walls, roofs and floors. Its main function is to prevent external heat from entering the cold storage, thereby maintaining a stable low-temperature environment. If the cold storage is compared to a huge refrigerator, then the PC41 is the “thermal insulation wall” of this refrigerator, it is like a solid barrier.Keep hot air out.

(II) Interpretation of core parameters

1. Density

Density is one of the important indicators for measuring PC41’s performance, usually expressed in kg/m³. Generally speaking, the higher the density, the greater the mechanical strength of the material, but the thermal conductivity will also increase accordingly. Therefore, in practical applications, a balance point needs to be found. The following are several common density ranges and their applicable scenarios:

Density range (kg/m³) Features Applicable scenarios
30-40 Light weight, low thermal conductivity Roof insulation
40-60 Excellent comprehensive performance Wall insulation
60-80 High strength, strong compressive resistance Floor insulation

2. Thermal conductivity

Thermal Conductivity is the core parameter for measuring the insulation properties of a material, usually expressed in units of W/(m·K). For PC41, the lower its thermal conductivity, the better the insulation effect. According to the ASTM C518 standard, the thermal conductivity of a qualified PC41 should be less than 0.024 W/(m·K). This means that even if the temperature outside changes drastically, the interior of the cold storage can remain relatively stable.

3. Coverage rate

Closed cell ratio refers to the proportion of the volume of closed air bubbles in the material. Higher closed porosity helps reduce moisture penetration and improve thermal insulation effect. The closed-cell rate of high-quality PC41 is generally above 95%, which makes it able to resist the influence of humid environment and extend its service life.

4. Compressive strength

Compressive strength reflects the performance of the material when it is subjected to external pressure. This is especially important for ground insulation. For example, when forklifts frequently enter and exit the cold storage, the ground insulation layer must have sufficient compressive resistance to avoid deformation or damage.

parameter name Unit Typical value range Remarks
Density kg/m³ 30-80 Adjust to use
Thermal conductivity W/(m·K) <0.024 Complied with ASTM C518 standard
Closed porosity % >95 Providing excellent waterproofing
Compressive Strength MPa 0.2-0.8 Depending on the application scenario

(III) Advantages and limitations of PC41

Advantages:

  1. High-efficiency insulation: Due to its ultra-low thermal conductivity, PC41 can achieve ideal insulation effect at a smaller thickness.
  2. Convenient construction: Use spraying technology to quickly cover complex surfaces, saving time and cost.
  3. Strong durability: PC41 can maintain good performance even if exposed to humid environments for a long time.

Limitations:

  1. Higher cost: Compared with traditional insulation materials (such as rock wool boards), the PC41 is slightly more expensive.
  2. High requirements for construction technology: During the spraying process, temperature, humidity and other factors need to be strictly controlled, otherwise the final effect may be affected.

III. Principles and methods for testing thermal conductivity of ASTM C518

Since it is mentioned that PC41 needs to meet the ASTM C518 standard, we have to understand the specific content of this test in depth. The full name of ASTM C518 is “Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus” (a standard test method for measuring steady-state heat transfer characteristics through protective hot plate devices). Doesn’t it sound a bit difficult to pronounce? Don’t worry, we explain it in simpler language.

(I) Test principle

ASTM C518 is based on steady-state heat transfer theory and calculates its thermal conductivity by measuring the temperature difference and heat flow on both sides of the sample. Suppose we have a sandwich cookie with a layer of cream (representing insulation material) in the middle, and then heat and cool on the upper and lower two cookies respectively.. If we know how much heat is input and the temperature difference between the upper and lower biscuits, we can calculate the thermal conductivity of the cream. Similarly, the thermal conductivity of PC41 can also be obtained through a similar method.

(II) Test device

The test device mainly includes the following parts:

  1. Hot plate: As a heat source, a constant heat is provided to the sample.
  2. Cold plate: absorbs heat from the sample and maintains a low temperature environment.
  3. Protective panels: Surround the hot and cold panels to prevent heat loss at the edges and ensure accurate test results.
  4. Temperature Sensor: Monitor the temperature changes on both sides of the sample in real time.

The entire device is like a precision balance, accurately weighing the flow of heat.

(III) Test Steps

  1. Sample Preparation: Cut PC41 samples of a certain size (usually 300mm×300mm×50mm) and ensure that the surface is flat and free of defects.
  2. Installation and debugging: Place the sample between the hot plate and the cold plate, and adjust the device to the initial state.
  3. Data Collection: After starting the device, record the temperature and heat flow data over a period of time.
  4. Result calculation: According to the formula ?=Q/(A·?T), the thermal conductivity coefficient ? is calculated, where Q is the heat flow, A is the sample area, and ?T is the temperature difference.

It should be noted that in order to ensure the reliability of the test results, each group of experiments is repeated at least three times and the average value is taken as the final result.

IV. Key control points of PC41 spraying process

To make PC41 meet the requirements of ASTM C518 standard, not only high-quality raw materials are required, but also exquisite construction technology is required. Here are a few key control points we have summarized:

(I) Raw material ratio

Polyurethanes are produced by the reaction of isocyanate and polyols, so their proportions directly determine the performance of the final product. Generally speaking, the isocyanate index (Index) should be within the range of 100±5. Too high index can cause the material to become brittle, while too low can affect the closed porosity.

(II) Environmental Conditions

Spraying operations are very sensitive to ambient temperature and humidity. The ideal working conditions are as follows:

  • Temperature: 15-25?
  • Humidity:<85%

If the environment is too humid, it may cause condensation on the surface of the foam, which will affect the insulation effect.

(III) Spraying technology

The following aspects need to be paid attention to during the spraying process:

  1. Spray gun distance: Maintain an appropriate distance (about 60cm) to ensure uniform coating.
  2. Spraying angle: Perpendicular to the surface of the substrate to avoid uneven thickness due to angle deviation.
  3. Layered Spraying: The thickness of a single spray should not exceed 20mm, otherwise it may lead to poor internal curing.

(IV) Maintenance time

After the spraying is completed, sufficient time is required to allow the material to cure fully. Usually, subsequent construction can be carried out after 24 hours, but it may take about 7 days to complete curing.

5. Case analysis: Application in a cold chain warehousing project

In order to more intuitively demonstrate the application effect of PC41, we selected a practical case for analysis. The project is located in a city in southern China, with a total area of ??about 5,000 square meters and a designed temperature of -18?.

(I) Project Background

The customer hopes to create a modern frozen warehouse for storing all kinds of frozen foods. After many comparisons, PC41 was finally selected as the insulation material. The main reason is its excellent insulation performance and convenient construction method.

(II) Implementation process

  1. Substrate treatment: Carry out comprehensive cleaning of walls, roofs and floors to ensure that the surface is clean and oil-free.
  2. Spraying Construction: In accordance with the above process requirements, spray PC41 layer by layer, with a total thickness of 100mm.
  3. Quality Test: After the construction is completed, a third-party organization is invited to conduct thermal conductivity tests in accordance with the ASTM C518 standard. The results show that all areas meet the design requirements.

(III) Effectiveness Assessment

After a year of actual operation, the cold storage performed well, and its energy consumption was reduced by about 20% compared to the traditional insulation solution. The customer is very satisfied with this and plans to continue to promote the application of PC41 in other projects.

VI. Conclusion and Outlook

Through the detailed analysis of this article, we can see that the PC41 polyurethane spray insulation layer has shown great potential in the cold chain warehousing field with its excellent performance. However, to give full play to its advantages, we must strictly control each and every time during the construction process.link. In the future, with the continuous advancement of technology, I believe that PC41 will shine in more fields.

Later, I borrow a classic saying as the end: “Success is not the end, courage is the real power to move forward.” May every practitioner be brave enough to move forward in his position and jointly promote the development of the industry!

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