Understanding the various size parameters of silicone tubes is beneficial for your business. This article will introduce the three key dimensions of the inner diameter, outer diameter and wall thickness of silicone tubes, as well as their applications.
We hope it can help you avoid mistakes in selecting the size of silicone tubes, reduce returns and exchanges, and stabilize the delivery of downstream customer orders.
Standard Sizes of Silicone Tubes
Before introducing several dimensions of the silicone tube, it’s important to note that the dimensions of the silicone tube have three core parameters that you need to understand:
- ID (Inner Diameter): The inner diameter significantly affects flow capacity and pressure loss within the system. You can determine the flow rate of the fluid and also limit the size of the medium that can pass through. If the inner diameter of your silicone tube is incorrect, it will directly affect the efficiency of the entire equipment.
- OD (Outer Diameter): The outer diameter of the silicone tube is related to the installation space reserved for your equipment and also determines whether it can match with your equipment connector. If the outer diameter of your silicone tube is not compatible, it may cause loosening and sealing leakage problems.
- Wall Thickness: Wall thickness is one of the primary factors affecting the pressure resistance of your silicone tubes. A thick tube wall can enhance the resistance to tearing of the silicone tube, and extend the overall service life of the pipeline.
Micro Silicone Tube Sizes
The micro silicone tubes can be produced through a reliable extrusion process by some specialized manufacturers, with an inner diameter as small as 0.007 inches (approximately 0.18mm) and an outer diameter as small as 0.015 inches (approximately 0.38mm).
These micro silicone tubes can be used in minimally invasive medical devices, catheter systems, and other applications. Many manufacturers classify silicone tubes with an inner diameter below 1 mm as micro silicone tubes, although no universally accepted definition exists.
The inner diameter range of micro silicone tubes is typically 0.05mm to 1mm, with 0.3mm, 0.5mm, and 1mm being common sizes.
The outer diameter usually ranges from 0.25mm to 6mm. The wall thickness can usually be calculated from the outer and inner diameters, with the minimum wall thickness reaching 0.1mm, and common thin-wall sizes include 0.15–0.20mm, 0.178mm, etc.
Standard Silicone Tube Sizes
In various industries, silicone tubes with an inner diameter ranging from 0.5mm to 25.4mm are widely used.
You can choose the mainstream and commonly used specifications in the industry, including sizes such as 0.8×1.7mm(ID × WT), 4.8×1.6mm (ID × WT), and 6.4×1.6mm(ID × WT), which can be used in laboratories , analytical instruments, and peristaltic pump systems.
The various sizes can meet the different usage needs of your customers, such as fluid transportation, sample collection, and circulation pump bodies.
Large Diameter Silicone Tube Sizes
The inner diameter of large diameter silicone tubes can reach over 50mm. The common inner diameter range you are familiar with is 50.8mm – 102mm. Some custom manufacturers can produce tubing with diameters exceeding several hundred millimeters, suitable for large industrial piping silicone tubes.
The conventional wall thickness range of this type of silicone tube is 3mm to 6.85mm. Required wall thickness should be determined according to the operating pressure and mechanical requirements. However, if you have special requirements, you can also ask the supplier to customize the wall thickness.
| Tube Type | Inner Diameter (ID) | Wall Thickness |
| Micro Tube | 0.05 – 4 mm | 0.1 – 1.5 mm |
| Standard Tube | 0.5 – 25.4 mm | 1.6 – 3.2 mm |
| Large Diameter Tube | 25.4 – 100 mm+ | 3.2 – 6.0 mm+ |
| Reinforced Tube | 6.4 – 102 mm | 4.0 – 7.0 mm |
Applications of Silicone Tubes in Different Sizes
Medical Industry
Medical-related applications have the highest technical requirements for silicone tubes. If you plan to use them in this field, you need to have high standards for the size accuracy and certification of silicone tubes.
Minimally Invasive Surgery
The inner diameter range of minimally invasive surgical catheters is 0.05mm – 2mm. The tolerance accuracy is high, with tolerances controlled within ±0.01mm to ±0.025mm. You can use them as cardiovascular catheters, neurointerventional catheters, or channels for ophthalmic surgical instruments.
Drug Delivery Systems
For drug delivery systems such as insulin pump tubing, intravenous indwelling needles, and analgesic pumps, the inner diameter of your silicone tubes should be 0.3mm – 4mm. The inner wall should be smooth to minimize the risk of drug adsorption and facilitate fluid delivery.
Respiratory and Anesthesia
When you use silicone tubes in respiratory and anesthesia equipment, their inner diameters range from 3mm – 15mm. We recommend using silicone tubes that are resistant to knotting and have high transparency to facilitate the observation of condensate water.
For the silicone tubes used in these applications, you need to ensure that they may comply with ISO 10993, USP Class VI, or other biocompatibility standards.
Laboratory Use
The laboratory is also a field where silicone tubes are widely used. Buyers demand reliable batch consistency and full traceability of your silicone tubes.
You can use it for applications such as chromatographs, mass spectrometers, connection tubes, vacuum filtration pipelines, etc. The inner diameter range is usually 1.6mm to 12.7mm. However, before your customers use it, remember to remind them to verify compatibility with the specific chemicals and solvents used in the application.
General Industrial Use
The general industrial sector is more sensitive to the price of your silicone tubes, but has a wider tolerance for tolerances. In these applications, aging resistance and weather resistance are their primary concerns.
CIP/SIP Cleaning Lines
The inner diameter range of the silicone tubes in the online cleaning system for processing equipment is usually 12.7mm to 76.2mm. Your customers require silicone tubes that can withstand high-temperature steam (135°C+), are compatible with many commonly used CIP cleaning chemicals, and do not release any unpleasant odors.
High Flow Liquid Delivery
This type of silicone tube has a large inner diameter, usually ranging from 25.4mm to 100mm+. It can be used in applications such as industrial cooling water, agricultural irrigation, and chemical solvent transfer. However, before using it for chemical solvent transfer, you need to confirm chemical compatibility.
These applications have high working pressure, so we recommend that the wall thickness of your silicone tube be ≥ 4.8mm, or use fiber-reinforced silicone tubes.
How to Choose the Right Size Silicone Tubes?
When choosing different sizes of silicone tubes, in addition to considering the corresponding application requirements, you also need to take into account the actual working pressure when making the selection.
The wall thickness directly determines the pressure-bearing capacity of the pipeline. You should match the corresponding pressure to ensure the safety of use.
Thin-walled tubes generally offer greater flexibility, while thicker walls may provide improved resistance to deformation and vacuum collapse. Selection should be based on the requirements of the specific pump system.
You may encounter some special situations where ordinary thick tube walls may not meet the usage requirements. You can use braided silicone tubes with polyester or glass fiber reinforcement materials.
FAQ
What Are the Different Ways to Mark Silicone Tube Sizes?
There are two common ways of marking the specifications that you usually see and use: ID × wall thickness (such as 4.8 × 1.6mm) or ID × outer diameter (such as 6 × 10mm). When purchasing, the supplier will usually indicate which method is being used.
What Is the French (Fr) Size Seen When Purchasing Silicone Tubes?
The French Scale (denoted as Fr or F) is a specific external diameter marking system for medical catheters, widely used in fields such as urology and cardiology for interventional devices.
Since it indicates the external diameter and does not directly reflect the internal diameter, when purchasing, you must also confirm the Fr size and the required internal diameter value.
In What Ways Does Hardness Influence the Size Stability of Silicone Tubes?
The hardness directly affects the extrusion accuracy and size retention ability of the silicone tube. If you need high-quality silicone tubes, it is recommended to choose silicone tubes with a Shore A hardness ranging from 50 to 70. Because within this range, it provides a balance between flexibility and dimensional stability for many applications.
What Are the Differences in Size Selection Between Reinforced Silicone Tube and Standard Silicone Tube?
The reinforced silicone tube is designed by embedding polyester, glass fiber or aramid woven layers into the ordinary tube wall to enhance its pressure resistance. Therefore, the reinforced tube usually has a thicker wall, and you need to reserve sufficient installation space.
Reinforced silicone tubing generally has lower flexibility and may require a larger minimum bend radius than standard tubing. However, compared to the ordinary silicone tube, this type of silicone tube has relatively poorer flexibility.
What Is the Typical Size Tolerance of Silicone Tube?
In precision applications, the inner diameter deviation of small-sized tubes is controlled within ±0.04mm. The general outer diameter tolerance is ±10%, and the wall thickness tolerance is ±20%, but this is a relatively loose standard. The wall thickness tolerance of reinforced silicone tubes can be controlled within ±0.3mm.
The tolerance standards vary among different manufacturers, so you need to pay attention to this.
Final Thoughts
Legensilico is a professional silicone manufacturer in China, capable of providing you with various sizes of silicone tubes. If you need special-sized silicone tubes, please feel free to contact us at any time. We offer one-stop customization services and can produce silicone tubes according to your requirements.
