Low Pressure PU Foam Machine

Yongjia polyurethane low pressure machine has a compact structure and is easy to maintain.

We provide a 5-year warranty and full-process technical support to ensure your production is always efficient and stable.

Manufacturer Since 2006Exported to 60+ CountriesUp to 5-Year WarrantyOEM / ODM & CETurnkey + Training Support

Low Pressure PU Foaming Machine — Overview

A low pressure PU foaming machine meters and mixes two or three liquid polyurethane components (polyol, isocyanate and optional additives) through a mechanical mixing head and dispenses the reacting blend into a mold or cavity. Unlike high-pressure systems, a low pressure polyurethane foaming machine mixes at roughly 2–20 bar using a rotary stirrer, which makes it cost-effective, easy to maintain and well suited to flexible and semi-rigid molded foam.

Because the mixing head recirculates between shots, a low pressure foam dispensing machine handles frequent color and formula changes, making it a flexible choice for varied molded parts. Yongjia builds low pressure PU foaming machines with customizable output, two- or three-component metering, programmable shot weight and tailored mixing heads to match your part size and cycle time.

Typical applications include PU gaskets and filter end-caps, memory foam pillows, automotive and bike seats, insoles, decorative cornices, faux stone and anti-fatigue mats. For higher output rigid foam and panel lines, see our high pressure PU machine; for gasket sealing specifically, see the PU gasket dispensing machine.

Machine Structure

Low pressure PU foaming machine structure with mixing head, metering pump and tank cross-sections and flow path
Low pressure PU foam machine structure — A-side and B-side heated material tanks, metering pumps, cantilever mixing head and HMI control, with mixing-head, metering-pump and tank cross-sections and the material flow path.

How It Works

A low pressure PU foaming machine meters each component, blends them mechanically in a recirculating stirred mixing head at low pressure (2–20 bar), and pours the mix into your mould or cavity.

How a Low-Pressure PU Foam Machine Actually Works
1
MeteringMetering pumps dose polyol, isocyanate and any pigment or filler to the set ratio and shot weight.
2
Mechanical mixingA high-speed stirrer blends the components inside the mixing head at low pressure (2–20 bar) — no impingement needed.
3
PouringThe swing arm positions the head and pours the reacting mix into the mould, cavity or fixture.
4
Reaction & riseThe blend reacts and expands into flexible, semi-rigid, rigid or integral-skin foam, then cures to the target density.
5
Recirculate & flushBetween shots the head recirculates and is solvent-flushed via the cleaning tank, so color and formula changes are quick.

Technical Parameters

Foam ApplicationRigid / flexible / integral-skin foam
Mixing MethodLow-pressure mechanical stirring (~2–20 bar)
Model SeriesSPU-LS (2-component) / SPU-LR (3-component)
Shot Weight / Output15–2500 g per shot (model-dependent)
Components2 to 11 component
Pigment / FillerSupported
Control SystemDELTA / SIEMENS PLC + DELTA HMI touch screen
CustomizationOEM/ODM, CE — mixing head, output & automation configurable

Core Components

Mechanical Mixing HeadHigh-speed stirrer blends the components at low pressure; mounted on a swing arm for flexible, repeatable pouring.
Metering PumpsPrecise pumps dose each component to the set ratio and shot weight, driven by dedicated motors.
Heated Material TanksPOLY and ISO day tanks with heaters and a level display keep raw material at stable temperature and viscosity.
FilterIn-line filter protects the metering pumps and mixing head from particles in the raw material.
Cleaning TankSolvent-flush system clears the mixing head between shots, enabling fast color and formula changes.
Control CabinetDELTA / SIEMENS PLC with touch-screen HMI sets shot weight, ratio, timing and pouring sequence.

Low Pressure Machine Types

Choose by how many separate metered streams your formula needs — from a simple two-component build to a multi-component system with up to eleven streams.

Two-Component (2K)
Two-Component (2K)SPU-LS seriesMeters polyol and isocyanate in two independent streams — the workhorse build for standard flexible, semi-rigid and rigid molded foam such as pillows, seats, insoles, cornice and faux stone. Simple, reliable and easy to operate, with shot weight from 15 to 2500 g and optional pigment or filler dosing.
Multi-Component (3–11 Component)
Multi-Component (3–11 Component)SPU-LR seriesAdds separate metered streams for color / pigment, filler, catalyst, blowing agent and other additives — from three up to eleven components. Ideal for precise color matching, filled or reinforced foam and complex recipes, letting you adjust the formula on the fly without pre-mixing. Each stream is independently metered and controlled.

Low Pressure vs High Pressure

Low pressure suits flexible and molded foam, integral-skin parts and frequent formula or color changes at small-to-medium output; high pressure suits high-output rigid foam and continuous panel lines. The right choice depends on your part, output, mould count and how often the formula changes.

 Low PressureHigh Pressure
Mixing methodMechanical / dynamic stirringHigh-pressure impingement (self-cleaning head)
Solvent flushYes — cleaning tankNot required
OutputShot 15–2500 g, small to mediumHigh, 90–450 kg/min
Best forFlexible / molded / integral-skin foam, frequent changesHigh output, stable formula, rigid & panels
Components2 to 11 componentTwo to three component
InvestmentLowerHigher

See our high pressure PU machine or the guide High vs Low Pressure: which is better?

How to Choose the Right Configuration

Tell us your product and target shot weight and our engineers size the machine. As a quick guide:

Your product / requirementRecommended configuration
Memory-foam pillowTwo-component low-pressure machine + pillow mould / carousel
Car or bike seat, cushionMolded-foam build with matching mixing head and mould line
Shoe sole / insoleLow-pressure machine sized to shot weight + sole mould line
Gaskets & filter end-capsFIPFG / dispensing configuration — see the gasket dispensing machine
Frequent color or formula changesRecirculating head + cleaning tank; 3-to-5-component for additives
Integral-skin parts (armrest, steering)Skin-foam build with temperature control
High-output rigid foam / panelsCompare our high pressure PU machine

Configuration & Options

Every machine is built to your product, shot weight and mould. A typical build:

Standard Configuration
  • Two-component low-pressure metering
  • Mechanical mixing head on a swing arm
  • Heated, agitated POLY / ISO day tanks
  • Precise metering pumps with dedicated motors
  • DELTA PLC + touch-screen HMI
  • Solvent-flush cleaning tank
Optional / Custom
  • Three- to five-component metering
  • Pigment / color and filler dosing
  • SIEMENS PLC upgrade
  • Carousel, conveyor or rail mould line
  • Drying / curing oven line integration
  • Custom output, voltage and tank volume
  • Moulds & fixtures, installation, operator & formula training, OEM/ODM, CE and a five-year warranty

Applications & Advantages

Yongjia’s low pressure PU foaming machines are used across furniture and bedding, automotive seating, footwear, sealing and decorative products. The recirculating mixing head and solvent-flush cleaning tank make color and formula changes fast, while 2-to-5-component metering supports pigment, filler and additive systems — a flexible, cost-effective choice from a China manufacturer since 2006, exported to 60+ countries with OEM/CE support.

Request a Quote for Your Application →

Frequently Asked Questions

What is a low pressure PU foaming machine?
It is a polyurethane dosing system that meters polyol and isocyanate (plus optional color or additives), mixes them mechanically in a recirculating mixing head at low pressure (about 2–20 bar), and pours the mixture into a mold to form flexible or semi-rigid PU foam.
What is the difference between low pressure and high pressure PU foaming machines?
A low pressure machine mixes mechanically and requires solvent flushing, but costs less and is ideal for flexible molded foam, frequent formula changes and small-to-medium output. A high pressure PU machine uses impingement mixing (100–200 bar), needs no solvent flush, and suits high-volume rigid foam such as insulation panels and refrigerators.
What can a low pressure PU foaming machine produce?
Common products include memory foam pillows, car and bike seats, PU soles and insoles, gaskets, filter end-caps, decorative cornice, faux stone and anti-fatigue mats.
How many components and what output can the machine handle?
We offer two- and three-component low pressure PU foaming machines. Output (g/s), tank capacity, number of mixing heads and shot weight are all configured to your application—tell us your part weight and target cycle time and we will size the system.
Can the machine be customized, and what is the MOQ and lead time?
Yes. Mixing head, output, automation level and pouring layout are customizable. As a China manufacturer we support OEM/ODM and CE certification. Contact us with your part specification for an exact configuration, price and lead time.

Get a Price Quote

Tell us your output, mold and automation requirements — our engineers reply within 24 hours with an exact price, configuration and lead time. OEM/ODM & CE supported.

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