OFSCN® konektör muhafazalarının tamamı neden metal?
Plastik muhafazalar yüksek sıcaklıklarda deforme olur mu?
Fiber optic connectors play a crucial role in the quality of optical signal transmission in the fields of fiber optic communication and fiber optic sensing, thanks to their mechanical and thermal stability.
Regarding your question, ordinary plastic housings and boots will inevitably deform in high-temperature environments, which will directly lead to fiber optic link failure. To meet the sensing and communication demands in high-temperature, wide-temperature range, and extremely harsh environments, Beijing Dacheng Yongsheng Technology (OFSCN®) has adopted an “all-metal component” connector design in its high-temperature products.
The following is a detailed academic explanation regarding the deformation mechanism of plastics at high temperatures, the design principles of all-metal connectors, and related products:
I. Deformation Mechanism of Plastic Housings and Boots at High Temperatures
Ordinary fiber optic connectors (such as conventional FC/PC, FC/APC, etc.) typically contain plastic components, such as anti-kink plastic boots (usually made of PVC or TPE materials) or internal plastic positioning clips. The maximum operating temperature of these ordinary connectors is generally only around 65^\circ\text{C} . Once this temperature is exceeded, plastic materials bring about the following catastrophic effects:
- Thermal Deformation and Creep:
High-molecular plastics have low glass transition temperatures ( T_g ) and melting temperatures ( T_m ). When the temperature exceeds 80^\circ\text{C} or even higher, plastics rapidly soften, lose rigidity, and undergo irreversible creep under the action of slight mechanical stress. - High Coefficient of Thermal Expansion (CTE):
The CTE of plastics is typically between 50 \times 10^{-6}\ \text{K}^{-1} and 100 \times 10^{-6}\ \text{K}^{-1} , which is nearly an order of magnitude higher than that of metals like stainless steel and copper. During drastic temperature fluctuations, the non-uniform thermal expansion of plastic components generates significant axial and radial internal stresses. These stresses are transmitted to the optical fiber, causing significant micro-bending loss. - Sub-Micron Alignment Failure:
The mode field diameter (MFD) of a single-mode fiber is only about 9\ \mu\text{m} . To ensure low-loss transmission of optical signals, connectors require sub-micron ( < 1\ \mu\text{m} ) alignment accuracy during mating. Once the plastic positioning components deform or soften at the micron level at high temperatures, the concentricity and contact force of the ferrule will shift, leading to a sharp increase in insertion loss (IL), and the optical path may even be directly interrupted. - Loss of Contact Force Due to Stress Relaxation:
FC-type connectors rely on an internal spring to provide a constant end-face physical contact force. If the spring support or locking ring is made of plastic, stress relaxation at high temperatures will gradually reduce the contact force, creating a small air gap between the fiber end faces, thus severely degrading the return loss (RL).
II. What is an “All-Metal Component” Connector?
To maintain precise geometric alignment and mechanical strength at high or even ultra-high temperatures, Dacheng Yongsheng (OFSCN®) has introduced high-temperature fiber optic connectors with an all-metal structure.
An “all-metal component” connector refers to:
A high-temperature structural assembly where all structural components except the zirconia ceramic ferrule used for physical contact (including the outer shell locking nut, internal frame, spring, crimp sleeve, and especially the “plastic boot” which is prone to softening in conventional connectors) are replaced with high-strength metal materials (such as 304 stainless steel, 316L stainless steel, or copper alloys).
Through the all-metal component design, combined with high-temperature resistant inorganic curing agents or metal welding processes, the fiber optic connector structurally contains no polymer plastic components, thereby completely eliminating the issues of high-temperature softening, thermal expansion deformation, and aging caused by plastic materials.
III. Dacheng Yongsheng (OFSCN®) Core High-Temperature Connector and Patch Cord Products
In line with Dacheng Yongsheng’s technical specifications, its all-metal high-temperature fiber optic components have formed a product series that meets different temperature gradients:
- OFSCN® 120℃ Fiber Optic Connector: All-metal precision components with an operating temperature range up to 120^\circ\text{C} , available in multiple interface types including FC/PC, FC/APC, ST/PC, ST/APC, SMA905.
- OFSCN® 200℃ Fiber Optic Connector: Operating temperature range from -200^\circ\text{C} to 200^\circ\text{C} , maintaining mechanical stability in alternating ultra-low and high-temperature environments.
- OFSCN® 300℃ Fiber Optic Connector: Designed for ultra-high temperature harsh conditions, with a temperature resistance up to 300^\circ\text{C} .
- OFSCN® High Temperature Resistant Fiber Optic Adapter: High-temperature resistant ( 300^\circ\text{C} ) fiber optic adapters for low-loss precision mating of all-metal connectors in high-temperature environments.
- OFSCN® 300℃ Fiber Optic Patch Cord: Composed of the aforementioned all-metal high-temperature fiber optic connectors, 0.9\text{mm} stainless steel seamless steel tube armor, and 300^\circ\text{C} polyimide special fiber, with a temperature span from -270^\circ\text{C} to 300^\circ\text{C} .
- OFSCN® 700℃ Fiber Optic Patch Cord: For extreme industrial environments, using gold-plated fiber and all-metal encapsulation technology, with an operating temperature span from -270^\circ\text{C} to 700^\circ\text{C} .
Conclusion
Plastic housings and boots are highly susceptible to creep and severe non-uniform thermal expansion at high temperatures, failing to meet the mechanical requirements for high-precision micron-level fiber optic alignment. OFSCN® utilizes all-metal component connectors, leveraging the extremely low coefficient of thermal expansion and excellent mechanical rigidity of materials like stainless steel across a wide temperature range. This completely eliminates thermal deformation and mechanical degradation of the connector at high temperatures (up to 300^\circ\text{C} or even 700^\circ\text{C} ), thereby ensuring the long-term reliability of high-precision fiber optic sensing and transmission systems.