Reliable High-Pressure Systems & Engineering Solutions

On Line Controls, Inc. provides MicroAir ultra-low air pressure regulators and controllers for plastic tubing extrusion, along with motorized potentiometers and related repair support. MicroAir products are designed for internal air support during free extrusion and can help stabilize tubing outside diameter in applications such as medical tubing, catheters, straws, and automotive tubing.

The right MicroAir model depends on how your line is controlled. MicroAir I is a manual model, MicroAir II uses up/down buttons and can accept contact closures, and MicroAir IV accepts 0–10 volt input for high-speed switching, bump and taper tubing, or PLC connection. Single through four-channel configurations are available for different line requirements.

Many MicroAir units less than 10 years old can be serviced, often in one day after receipt and testing. Older units may be sent in for evaluation. Units with serial numbers below 7000 are not repairable because the internal body is typically worn after about 20 years of use. Repair cost is provided after inspection.

All MicroAir units are covered by a three-year manufacturer’s warranty on parts and labor. The warranty supports OLC’s focus on long product life, low maintenance, and dependable operation. For out-of-warranty repairs, a purchase order may be required, and the final repair cost is determined after the unit is received and tested.

MicroAir regulators are designed for stable, hysteresis-free operation with no calibration required. This helps extrusion teams reduce maintenance demands and keep production lines running consistently. The systems are built to respond instantly to changes in air flow, supporting precise control even during cuts, spooling, and other process changes.

OLC serves manufacturers that produce extruded plastic tubing and profiles, including medical device tubing, catheter tubing, plastic straws, and automotive tubing. Extruder OEM manufacturers also use OLC products. The systems are especially valuable where precise tubing outside diameter, consistent internal air support, and long-term control reliability are critical.

Yes. MicroAir units are manufactured in the United States at OLC’s Shrewsbury, Massachusetts facility and can be shipped worldwide by UPS, DHL, or FedEx. The company serves customers across multiple countries, including the United States, Canada, Mexico, Germany, Japan, China, India, France, and other manufacturing markets.

Yes. OLC sells DC and AC motorized potentiometers and offers repair or rebuilding for motorized potentiometers built by On Line Controls, Inc. The service team also attempts to repair older OEM ETI motorized potentiometers, including MC, MAC, and ME series units from the 1980s and 1990s, depending on parts availability.