Venturi Injectors

Mazzei venturi injectors are differential pressure injectors with internal mixing vanes. The unique, patented design and precision construction of Mazzei injectors maximizes injector efficiency, suction capacity and mixing capabilities. Our injectors also have no moving parts, which simplifies maintenance, and they have much lower operating costs than less efficient systems.

How a Mazzei Venturi Injector Works

When pressurized water enters the injector inlet, it is constricted toward the injection chamber and changes into a high-velocity jet stream. The increase in velocity through the injection chamber results in a decrease in absolute pressure, creating a vacuum that draws a liquid or gas additive through the suction port and mixes it thoroughly into the water stream. As the jet stream is diffused toward the injector outlet, its velocity is reduced and resumes its flow in a thoroughly mixed state with slightly lower energy than when it entered the injector.


Mazzei venturi injectors operate over a wide range of pressures and require only a minimal pressure differential between the inlet and outlet sides to initiate a vacuum at the suction port. The injectors’ internal mixing vanes create thousands of microbubbles, which greatly increases the surface area of gas (air, oxygen, ozone, etc.) in contact with the liquid. Several microbubbles have a greater surface area than one large bubble of the same volume. Higher surface area facilitates greater solubility.

Use the INJECTOR SELECTOR TOOL to determine which injector
will fit your application needs when injecting a liquid additive into a water stream.



Sometimes a picture is worth a thousand words… to get a better understanding of how a Mazzei injector works, view our animation.

Why Choose Mazzei Injectors?

  • Offers proven performance with years of expected service
  • Requires no electrical connections
  • Runs dry with no problems
  • Provides considerable cost savings over other injection methods
  • Safe to use as the chemicals are injected under vacuum, not pressure
  • Imitations don’t perform as well as a Mazzei
  • Available in stainless steel, polypropylene (PP), polyvinylidene fluoride (PVDF), or natural PVDF



Stainless Steel:

Potable water and the food and beverage industries use stainless steel injectors.

Stainless steel ensures:

  • Absolute performance
  • Longer life
  • Compliance with FDA and international standards for food processing.

Polypropylene (PP):

  • Highly resistant to most acids and alkalis
  • Versatile and cost-effective
  • High tensile strength
  • Lightweight and rigid

Polyvinylidene Fluoride (PVDF):

  • Advanced thermoplastic superior to PVC, PP, polyethylene and other plastics
  • Higher pressure and temperature-handling capabilities
  • Resistant to ozone
  • Resistant to sulfuric and nitric acids and chlorine
  • Better abrasion and wear resistance
  • Sunlight (UV) resistant
  • Dyed PVDF or Natural PVDF available
  • Grade NSF 61 and FDA approved (if required, use Natural PVDF since dyes used may not be approved)

Polyvinyl Chloride (PVC):

Some Mazzei injectors are made in PVC. Contact Mazzei for availability.