Masterflex Tubing Pump Systems FAQs

Masterflex Tubing Pump Systems FAQs

  1. How does a Masterflex tubing pump work?


Flow Rates
  1. What flow rates are attainable?


Pump Heads
  1. What is the maximum obtainable pressure?


Tubing
  1. Is the tubing important?


Drives
  1. Why are pump heads available without drives in the L/S, I/P, and B/T pump groups?


How does a Masterflex tubing pump work?

Each pump system is divided into three parts: pump head, drive, and tubing. The pump head consists of the rotor and housing; the drive creates the force needed to move the rotor; and the tubing acts as the pump chamber. These three parts pump fluid by following these steps:

  1. The tubing is placed into the tubing bed—between the rotor and housing—where it is occluded (squeezed).
  2. The rollers on the rotor move across the tubing, pushing the fluid. The tubing behind the rollers recovers its shape, creates a vacuum, and draws fluid in behind it.
  3. A "pillow" of fluid is formed between the rollers. This is specific to the ID of the tubing and the geometry of the rotor. Flow rate is determined by multiplying speed by the size of the pillow. This pillow stays fairly constant except with very viscous fluids.

View our simple animation that demonstrates a Masterflex tubing pump in motion.


Flow Rates
1. What flow rates are attainable?

Our Masterflex® Ismatec® pump systems deliver flow rates from 0.0011 to 365 mL/min with miniflex pump head. L/S® systems deliver flow rates from 0.0006 to 3400 mL/min. I/P systems deliver flow rates from 0.012 to 13 LPM and B/T® systems deliver flow rates from 0.3 to 45 LPM.


2. What flow precision can I expect?

You can obtain a flow precision of better than ±0.5% with calibrated flow systems. For other systems, you can obtain ±2 to 5% precision for general transfer applications.


3. Are measured volumes repeatable?

Volumes are repeatable with accuracies of ±0.5% or better using calibrated systems.


4. What is the effect of fluid viscosity on flow?

All flow rates are based on water. Increasing the fluid viscosity will decrease the flow rate.


Pump Heads
1. What is the maximum obtainable pressure?

Depending on the tubing you choose, the maximum obtainable pressure is 40 psi (2.7 bar); nominal pressure is 25 psi (1.7 bar).


2. What is the maximum inlet pressure?

Typically 40 psi (2.7 bar), depending on tubing ID, wall thickness, and formulation..


3. What is the maximum suction lift?

The maximum suction lift is 29 ft (8.8 m) H20.


4. Are check valves required?

No. Our unique designs eliminate this need.


5.Can Masterflex pumps run dry?

Yes. They can pump gases, liquids, or mixed phases.


6. Are Masterflex pumps self-priming?

Yes. They can develop a vacuum in excess of 26" Hg (660 mm Hg).


7. Are Masterflex pumps positive displacement type pumps?

Yes. The flow rate with water is directly proportional to the rotor speed up to the maximum capabilities of the drive.


8. Are Masterflex pumps nonsiphoning?

Yes. One roller is always squeezing the tubing closed, so you don't get any backflow.


9. Can slurries or abrasive solutions be pumped?

Yes. The limitations are viscosity and particle size relative to selected tubing ID. For hard particles, we recommend a tube inner diameter equal to 20x the particle diameter. For soft particles we recommend 4x.


10. Why are so many pump heads and tubing sizes offered?

Masterflex pumps are modular to fit most any application. We offer pump heads for higher pressures, shear-sensitive fluids, and small footprint requirements to name a few. This synergizes with the variety of Masterflex tubing available with such formulations for acids and bases, sensitive biologics, food, and many other types of fluids.


11. Is flow reversible?

Yes. Specifications apply in either clockwise or counterclockwise rotation.


Tubing
1. Is the tubing important?

The tubing is the pump chamber. The elasticity of the tubing provides suction lift; its strength provides pressure handling ability; its flexible characteristics determine pumping life; its bore determines the flow rate, and its wall thickness determines pumping efficiency.


2. What temperature ranges of materials can be pumped?

Optimum temperature range is from 32 to 104°F (0 to 40°C). The max. temperature range is from -40 to 302°F (-40 to 150°C) for tubing and from 32 to 104°F (0 to 40°C) for the pump head.


3. What is the chemical resistance?

Depends on tubing style (see Tubing and Chemical Compatibility Database).


4. What determines tubing life?

Many, many factors have an effect on tubing life. Pump speed, and system pressure, tubing material and chemical compatibility, abrasiveness of the liquid (media) being pumped, temperature of the fluid, and even the environment the pump is in have an effect. Visit our STAMP tubing guide for the step-by-step recommendation process followed by our applications team.


5. What tubing formulation gives longest life?

Norprene*, PharMed* BPT, Pharmapure, Puri-Flex, Tygon E-LFL*, silicone, C-FLEX**, and Viton***, in that order.


6. How does pump speed affect tubing life?

Tubing life is inversely proportional to pump speed. Minimum speed gives maximum life.


7. Is the tubing compatible for food and sterile applications?

Yes. Some tubing formulations meet NSF specifications and FDA and USDA requirements for food handling. Many can be sterilized.


8. Is the tubing difficult to replace?

No, tube replacement is actually very simple. The EASY-LOAD®, EASY-LOAD II®, High-Performance, cartridge, and RAPID-LOAD® pump heads make tubing changes quick and easy. With the Standard pump head, tubing is easy to change using the loading key provided.


Drives
1. Why are pump heads available without drives in the L/S, I/P, and B/T pump groups?

The modular concept lets you customize your system for maximum flexibility.


2. Can more than one pump head be used with a single drive?

Yes. Any number (typically two to four) can be stacked together in any combination using Standard or EASY-LOAD heads up to the maximum torque capability of the drive.


3. Are drive systems other than those shown in the general catalog available?

Yes. Our Engineering Department can customize, design, or modify a drive or drive package to your specifications for quantity purchases and OEM applications. Visit our website or Call 800-323-4340 or (from outside the U.S.) 847-549-7600.


* Norprene, PharMed®, Tygon—Registered Trademark Saint-Gobain Performance Plastics Corporation.
**C-FLEX—Registered Trademark Saint-Gobain Performance Plastics Corporation.
*** Viton®—Registered Trademark of The Chemours Company.