Peristaltic pump hose life: 10 causes of early hose failure

Peristaltic pump hose life depends on how many times the hose is compressed, how hard it is squeezed, how hot it runs and what it is pumping. A peristaltic hose pump moves liquid by compressing a reinforced rubber hose with a rotor, which makes the hose the main wear part. Every hose eventually fails from fatigue. The causes below bring that point forward, and most of them sit in pump setup, operating conditions or pipework that you can change.

No single hours figure applies to every hose. The same hose will last very different lengths of time at different speeds, pressures, temperatures and liquids, so the useful questions are what is shortening it and how to spot it early.

What wears out a peristaltic pump hose

Each turn of the rotor compresses the hose and lets it recover. Verder, which makes Verderflex hoses, says fatigue between the rubber layers and the reinforcement is the usual reason a hose fails, typically after several million cycles. As the reinforcement loses its elasticity, the hose stops returning fully to round and the pump delivers less flow on each revolution. That loss is gradual, so it can be measured before the hose fails.

Anything that adds compression cycles, adds load to each cycle or adds heat shortens that life. Running faster adds cycles. Over-tight shimming adds load. A hot pump or poor lubrication adds heat. Pulsation and restricted suction add shock loads. The ten causes below follow those lines.

• Incorrect shim placement:

  Shim adjustment is crucial for the hose to ensure its properly squeezed for efficient operation. The shims must be set to just close the hose together without heavy compression. This can be checked with a pressure gauge.

• Flow rate:

  Flow rate is limited to the internal dimensions of the hose. The faster you run the pump, the higher the flow rate, but this also increases the wear on the hose causing it to fail much sooner.

• Hose/product compatibility:

  If the hose is pumping non-compatible chemicals or liquids, the hose will fail at a greater rate. Our guide to peristaltic hose and tube materials compares the options. For a specific liquid, concentration and temperature, we recommend confirming the material with us before you order.

• Lubrication:

  Incorrect lubrication will create friction inside the hose and reduce hose life. We supply peristaltic pump lubricants for Verderflex pumps.

• Temperature:

  Ensure the maximum temperature for your pump head does not exceed the recommended max temperature.

• Pulsation dampening:

  If pressure surges or pulsations within the pump are not addressed, fatigue failure can occur.

• Discharge conditions:

  If the discharge is too long or has too many bends, it increases the friction losses. This can be avoided by having as direct route to the end point as possible.

• Not using original spare part:

  Using non-compatible spare parts can lead to hose pump failure. It is important to stock up on spare parts that meet the correct requirements from the correct supplier (Yes, we stock spares!). Verderflex hoses carry colour-coded lettering that identifies the material (white for NR, yellow for NBR, yellow with a white stripe for NBRF, red for EPDM and green for CSM), which makes it easy to check that the right one has been fitted. We cover this further in our comparison of Verderflex and non-OEM hoses.

• Pipeline design:

  • Keep the piping as straight and direct as possible. Unnecessary bends and valves cause undue stress on the entire pump.

  • Utilise pulsation dampeners where possible to reduce shock loads.

• Suction conditions

  • Long suction lengths rapidly wear out the hose.

  • Undersized suction pipework drastically fatigues the hose. Rule of thumb, try to go 1.5 times larger than your pump flanges for your suction. I.e. 50mm pump use a 75mm suction pipe.

Global Pumps YouTube channel: What Makes Hose Pumps DIFFERENT From Tube Pumps