What is a polyurethane high-pressure foaming injection machine?

A polyurethane high-pressure foaming injection machine is a specialized device that uses high-pressure impact mixing technology to precisely meter, pressurize, and heat two liquid chemical raw materials, thoroughly mixing them before injecting them into a mold or cavity. After mixing, these raw materials undergo a rapid chemical reaction, expanding and solidifying to form a polyurethane foam product.

1. Main Components
A typical high-pressure foaming machine typically consists of the following key systems:
Tank System:
This system stores the raw materials (material A and material B) and is typically equipped with an agitator and temperature control device to maintain a uniform and constant temperature.
Metering System:
This system consists of high-precision hydraulic or servo motor-driven metering pumps, ensuring the precise ratio of the two raw materials. The accuracy of the ratio directly determines the quality of the final product. High-Pressure Pumping System:
Metered raw materials are pressurized to very high pressures (typically between 100-200 bar, or even higher).
Temperature Control System:
Integrated heaters and heat exchangers heat the raw materials to the optimal process temperature for the reaction (typically 30°C to 60°C). Maintaining a constant temperature is crucial for maintaining stable raw material viscosity and reaction rates.
Mixing Head:
This is the core of the technology. Two high-pressure raw material streams collide and inject into a small mixing chamber. The energy of the high pressure itself achieves self-cleaning impact mixing, eliminating the need for a mechanical stirrer.
Advantages: Extremely uniform mixing, no residue, and automatic cleaning after each injection, preventing clogging.
Control System:
Typically utilizes a PLC (Programmable Logic Controller) and touchscreen human-machine interface (HMI). Operators can precisely set and store various process parameters, such as injection volume, ratio, pressure, temperature, and time, enabling automated production.

2. Working Principle (High-Pressure Impact Mixing)
Metering and Pressurization: The metering pump precisely draws materials A and B in a preset ratio, and the high-pressure pump pressurizes them.
Heating: The materials in the high-pressure pipeline are continuously heated and maintained at the set temperature during circulation.
Impact Mixing: When injection is required, the valve of the mixing head opens, and two high-pressure liquid streams collide at extremely high speeds. The enormous kinetic energy enables instantaneous and thorough mixing at the molecular level.
Injection and Reaction: The mixed liquid is injected into the mold, where a rapid chemical reaction occurs, causing foaming, expansion, and filling the mold cavity, ultimately solidifying and forming.
Self-Cleaning: After injection is completed, the mixing head valve closes, and the high pressure completely removes any remaining material from the mixing chamber, preparing it for the next injection.

3. Main Features and Advantages
Extremely High Mixing Quality: High-pressure impact mixing is more uniform and thorough than low-pressure mechanical mixing, producing foam with fine-pored cells and stable performance.
High Production Efficiency: Fast injection speeds and short cycle times make it suitable for large-scale, high-efficiency production.
Reduced Raw Material Waste: The self-cleaning mixing head eliminates residual material waste after each injection, saving costs.
Excellent Process Stability: Precise metering, constant temperature, and pressure ensure high repeatability and product consistency.
Flexible Operation: A wide range of adjustable parameters allows a single machine to produce a variety of products with varying densities, hardnesses, and shapes by adjusting the formulation and mold.