How to solve the problem of bubbles in silicone pipes?

Q1: “Why are Silicone Tubes more prone to foaming than rubber products? Is it a material defect?”

A : Silicone’s “high sensitivity” is the culprit!

Raw material differences : Silicone tubes rely on high-purity transparent silica , and impurities (such as other silica mixed in or PE bag residues) will directly cause bubbles. Traditional rubber products (such as EPDM) are more tolerant to impurities, but have poor temperature resistance (only 120°C).

Process challenges : Silicone mixing requires precise control of kneading temperature and time . If the mixing is insufficient (time < 30 minutes) or the temperature fluctuates (±5°C), the air in the rubber cannot be completely exhausted, forming bubbles39 . Due to the poor fluidity of rubber products, it is easier to cover up defects by simple pressing.

Industry truth : Medical-grade silicone tubes are required to be 99.99% sterile , but bubbles may harbor bacteria, so quality control is more stringent.

Q2: "The silicone tube was inspected and passed during production, so why does it bulge after being used for a long time?"

A : The invisible killers are the vulcanization process and storage environment !

Vulcanization defects :

Insufficient pressure or excessive mold temperature (>200°C) will cause the gas inside the rubber to expand and form vacuum bubbles (round bubbles with smooth surfaces).

Solution: By adopting segmented vulcanization - first low-pressure degassing and then high-pressure shaping, the Tesla cooling pipe factory has reduced the defective rate to 0.5%.

Improper storage :

If the silicone tube is exposed to moisture or light, the moisture will penetrate and hydrolyze the silicone to produce tiny bubbles.

Comparison: Rubber products are more hydrophobic and have slightly better moisture tolerance, but they will still age and crack over the long term.

Q3: “Will bubbles in food-grade silicone tubes be harmful to health? How can we solve this problem completely?”

A : Bubbles = breeding ground for bacteria! The medical and food industries must have “zero tolerance”!

Risk analysis : Bubbles may contain residual detergents or microorganisms. The FDA once initiated a recall due to bubble problems in a certain brand of infusion tubes.

The ultimate solution :

Raw material upgrade : Medical grade silica (purity>99.9%) is selected, and an anti-stick coating is applied to the inner wall of the kneader to prevent impurities from mixing in.

Vacuum mixing : Extend the mixing time in the vacuum kneader for 10 minutes to completely expel the air in the Rubber Compound.

Laser quality inspection : Huawei suppliers use laser scanning technology to detect bubbles on the tube wall in real time with an accuracy of 0.01mm.

Q4: “Rubber products are cheaper, why not just use Rubber Tubes?”

A : The "superpowers" of silicone tubes are far beyond the reach of rubber!

Temperature resistance : Silicone tubes can withstand -60℃~200℃, while rubber (such as NBR) softens and deforms at 120℃.

Chemical resistance : Silicone can withstand strong acids and alkalis with a pH of 1-14, while rubber easily swells when exposed to oil or solvents.

Lifetime cost : A silicone tube can be used for 5-10 years, while a rubber tube is replaced every 2 years on average, so the long-term cost doubles.

Pro Tips: Engineers’ Secret Bubble Repair Technology

DIY first aid : Small bubbles can be filled with medical silicone repair agent . After curing, the pressure resistance will be restored to 80%.

Process parameter table : mixing temperature 60-80℃, kneading time 35-45 minutes, vulcanization pressure 15-20MPa (data from BMW supply chain).

Storage tool : When storing silicone tubes, place desiccant bags inside and avoid stacking (hanging storage is recommended)

For more information, please contact: ( https://www.cmaisz.com/ ).