What should I pay attention to when choosing a peristaltic pump silicone tube?
The peristaltic pump is composed of a driver, a pump head，and a hose. The peristaltic pump hose is an important working part of the peristaltic pump, and its performance affects the accuracy and stability of the peristaltic pump flow. As a flexible component, the hose has a certain service life and needs to be replaced regularly. So what parameters should we pay attention to when choosing a peristaltic pump tube
1. The peristaltic pump hose must have a certain degree of flexibility, and the hose can quickly recover its shape after being compressed radially (Shore hardness: 40-80).
2. Has a certain degree of wear resistance.
3. Have a certain ability to withstand pressure.
4. No leakage (good air tightness)
5. Low adsorption, temperature resistance, resistance to aging, no swelling, corrosion resistance, low precipitation, etc.
Choosing the right pump tube is as important as choosing the pump head. Conventional pump heads can be adapted to a variety of pump tube sizes. Special pumps usually require special-shaped pump tubing, hoop pump tubing components, or special joints.
The types of hose materials available on the market are extremely diverse, and the prices vary greatly. But only a few can be used as pump tube materials. Some materials are similar in appearance, but the pumping performance is quite different. A good pump tube should have excellent tensile and anti-extrusion properties. The pump tube material should be selected according to the application requirements and the operator's preference. However, special attention should be paid to the satisfaction of the following indicators:
When choosing a peristaltic pump for pumping corrosive fluids, the key is to choose the correct pump tubing material. Choosing the wrong pump tube will cause danger, possibly destroying equipment and endangering personal safety. Please consult the chemical compatibility table for each application provided by the pump and pump tubing manufacturer. Experiment with the pump before using new or unmarked chemical substances. Dip a short section of pump tubing into the fluid. Check the changes in the size, color, weight， and strength of the pump tube. If possible, test the pump tube in the pump before stretching it for use. When the pump tube is squeezed, it will bend, which will knead the chemical substance into the tube wall and accelerate the aging and disintegration of the tube.
In many applications such as laboratory research, pharmaceuticals, and biotechnology product production, fluid isolation is essential. A large number of studies have demonstrated that silicone tubes and silicon-based materials will not chemically react with various biological materials. Other types of materials also have this performance and can meet the requirements of USP Class VI. Some pumps use pump tube assemblies made of inert PTFE tubing.
Note: After a long-term operation, some particles in the pipe will separate and fall into the fluid. Experts call this the "stripping phenomenon". In some applications, such particles can be observed with the naked eye. To minimize the peeling phenomenon, the frequency of pipe replacement should be increased.
The ability of different pipes to withstand repeated rolling by rollers is also different. Generally speaking, the combination of the specific pump tube size, pump tube material, pump head, and operating speed determines the service life of the pump tube. The service life of the pump tubing, or the flexural yield limit in the pump, is the primary consideration before putting it into a new application. Nowadays, with the use of thermoplastic elastomer (TPE) in the system, it is very common for the pump tube to run for more than 500 hours.
In a particular application, the performance of the pump is very stable. Choosing pipes with greater resistance to flexing, using thicker pipe walls, and/or choosing larger pumps and using lower operating speeds can all extend the mission of the pump pipe to the limit.
For some applications, it is very valuable to be able to observe the movement of the fluid through the pipeline to clearly understand the working process of the pump or dry operation. But on the other hand, opaque tubing is good for some photosensitive fluids.
The hardness of the pipe wall is critical to determining the pumping capacity of a particular pipe. If the pump tube is too soft, it will be easily damaged; if the pump tube is too hard, the pump will not work. Hardness tester (such as Shore A, etc.) can be used to determine the physical properties of specific pipes.
Fluid pressure usually restricts the pump tube’s ability to deliver pressure fluid. Most peristaltic pumps use unsupported pipes. The pressure limit of this type of peristaltic pump tubing
is 2 to 3 bar (30 to 45 pounds per square inch). Some of the larger pumps on the market use supporting pipes (with braided reinforcement). The pump tubing immersed in the lubricating fluid can withstand pressures of up to 15 to 20 bar (300 pounds per square inch).