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Humidity Management in Plastic Injection Facilities

Humidity management plays a critical role in ensuring the success of plastic injection molding processes. In plastic injection facilities, maintaining optimal humidity levels is essential for producing high-quality plastic parts, minimizing defects, and protecting equipment. In this article, we'll explore the reasons why humidity management is crucial in plastic injection facilities, the process of plastic injection molding, and how desiccant dehumidification can mitigate the negative effects of high humidity.

Humidity management in plastic molding facilities by Innovative Air Technologies desiccant dehumidification systems
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Why Humidity Management Matters:

  1. Material Stability: Plastic injection molding processes require precise control over material properties, including moisture content. Excessive humidity can cause hygroscopic plastics, such as nylon and ABS, to absorb moisture from the air, leading to variations in material properties, reduced moldability, and inferior product quality.

  2. Reduced Defects: Proper humidity control helps minimize defects in molded plastic parts, such as warping, shrinkage, and surface imperfections. Moisture-related defects occur when water vapor trapped in the plastic material expands during the molding process, resulting in dimensional inaccuracies and cosmetic flaws in the finished products.

  3. Improved Flowability: Maintaining optimal humidity levels ensures consistent flow properties of molten plastic materials during injection molding. High humidity can cause polymer chains to stick together, resulting in poor melt flow and filling characteristics, while low humidity can lead to static charges and uneven material distribution within the mold cavity.

  4. Prevention of Equipment Damage: Excessive humidity can corrode metal components and electrical systems in injection molding machines, leading to equipment malfunctions, downtime, and costly repairs. Managing humidity helps protect sensitive equipment and prolong its lifespan, ensuring reliable performance and production uptime.

  5. Enhanced Mold Lifespan: Moisture can corrode and degrade injection molds, compromising their surface finish, dimensional accuracy, and longevity. Proper humidity management helps preserve mold integrity, preventing surface rust, pitting, and wear, and extending the lifespan of expensive tooling assets.

  6. Consistent Process Conditions: Fluctuations in humidity levels can lead to inconsistent process conditions, affecting the repeatability and reliability of injection molding processes. Stable humidity conditions ensure predictable outcomes, tighter tolerances, and higher product quality across production runs.

  7. Worker Comfort and Safety: Managing humidity creates a comfortable and safe working environment for operators and technicians in the plastic injection facility. Excessive humidity can cause discomfort, fatigue, and heat stress among personnel, impacting productivity and morale.

  8. Regulatory Compliance: Certain industries, such as automotive, medical, and electronics, have stringent quality standards and regulatory requirements for plastic components. Maintaining proper humidity control helps ensure compliance with industry standards, specifications, and customer expectations, reducing the risk of rejected parts, recalls, and legal liabilities.


Humidity Management in plastic molding facilites utilizing Innovative Air Technologies Desiccant dehumidifiers.


Understanding the Plastic Injection Molding Process:

Plastic injection molding is a manufacturing process used to produce a wide range of plastic parts and components. The process involves injecting molten plastic material into a mold cavity, where it cools and solidifies to form the desired shape. Here's a simplified overview of the plastic injection molding process:

  1. Material Preparation: The first step involves selecting and preparing the appropriate plastic resin for injection molding. Plastic resin is typically in the form of pellets or granules and may contain additives such as colorants, stabilizers, and fillers.

  2. Injection Molding Machine Setup: Once the material is prepared, it is fed into the injection molding machine, where it is heated to a predetermined temperature and pressure. The machine consists of a hopper, barrel, screw, and mold cavity, as well as heating and cooling systems.

  3. Injection: The heated plastic material is injected into the mold cavity under high pressure, filling the cavity and taking on the shape of the mold. The mold is typically made of steel or aluminum and is precision-machined to the desired specifications.

  4. Cooling and Solidification: After the mold cavity is filled, the plastic material is allowed to cool and solidify, taking on the shape of the mold. Cooling time varies depending on the material type, part geometry, and mold design.

  5. Ejection: Once the plastic part has solidified, the mold opens, and the finished part is ejected from the mold cavity. The process is repeated for each cycle, with the injection molding machine automatically controlling the sequence of operations.

Humidity Management in plastic molding facilites utilizing Innovative Air Technologies Desiccant dehumidifiers.

Mitigating Humidity Effects with Desiccant Dehumidification Technology:

Desiccant dehumidification offers an effective solution for mitigating the negative effects of high humidity in plastic injection facilities. Desiccant dehumidifiers remove moisture from the air using a desiccant material, such as silica gel or molecular sieve, which adsorbs excess humidity from the air.


Here's how desiccant dehumidification can help:

  1. Precise Humidity Control: Desiccant dehumidifiers allow for precise control over humidity levels in the facility, ensuring optimal conditions for plastic injection molding processes. By maintaining consistent humidity levels, desiccant dehumidifiers help prevent moisture-related defects and ensure high product quality.

  2. Equipment Protection: Desiccant dehumidifiers help protect injection molding machines, molds, and other equipment from corrosion and moisture damage. By reducing humidity levels, desiccant dehumidifiers prolong the lifespan of equipment and minimize the risk of costly repairs and downtime.

  3. Energy Efficiency: Desiccant dehumidifiers are energy-efficient solutions for humidity management in plastic injection facilities. By removing moisture from the air, desiccant dehumidifiers reduce the workload on HVAC systems and refrigeration equipment, leading to lower energy consumption and operating costs.

  4. Worker Comfort: Maintaining optimal humidity levels with desiccant dehumidification technology creates a comfortable and safe working environment for personnel in the plastic injection facility. By controlling humidity, desiccant dehumidifiers help prevent discomfort, fatigue, and heat stress among workers, improving productivity and morale.


Humidity management is essential for achieving optimal results in plastic injection molding processes. Proper humidity control helps ensure product quality, process efficiency, equipment reliability, and worker safety in plastic injection facilities. By leveraging technologies such as desiccant dehumidification, plastic injection manufacturers can enhance their competitiveness, meet customer expectations, and drive success in the industry.

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