What are the application requirements of stainless steel strong torsion double spring in medical devices

As one of the key mechanical components in medical devices, stainless steel strong torsion double springs undertake important functions such as torque transmission, energy storage and precise control. Its performance is directly related to the safety, reliability and service life of medical equipment.

Material requirements: high purity and biocompatibility
Medical device springs must be made of high-quality stainless steel materials, usually 316L or special medical grade stainless steel. This type of material has excellent corrosion resistance and good biocompatibility, and can work stably for a long time in human contact environments.
High-purity materials reduce impurities and inclusions, prevent local corrosion and stress corrosion cracking. Biocompatibility ensures that the spring will not cause allergic reactions or toxicity, and meet the safety standards and regulatory requirements of medical devices.

Mechanical properties: high strength and fatigue life
Strong torsion double springs in medical devices are often subjected to repeated torsion and deformation, and mechanical properties are particularly critical. The spring must have high yield strength and elastic limit to ensure that no permanent deformation or breakage occurs during use.
Fatigue life is an important indicator for evaluating spring performance. Medical equipment requires springs to maintain stable performance after hundreds of thousands or even millions of cycles to avoid equipment failure or malfunction. By rationally designing the wire diameter, number of turns and torque stiffness, the use requirements of high-frequency dynamic loads can be met.

Surface treatment: improving corrosion resistance and cleanliness
In medical environments, springs need to resist corrosion from body fluids, disinfectants and various chemical reagents. The surface must be polished, electrolytically polished and passivated to remove surface defects and improve the uniformity and density of the oxide film.
The high-finish surface not only improves corrosion resistance, but also facilitates cleaning and sterilization, reducing the risk of bacterial adhesion and cross-infection. The surface treatment process meets the medical cleanliness standards and is the key to ensuring the long-term safe use of springs.

Dimensional accuracy and shape stability
The precise structure of medical devices has extremely high requirements for spring size and shape accuracy. During the spring manufacturing process, the wire diameter tolerance, number of turns and end shape must be strictly controlled to ensure assembly accuracy and functional reliability.
Shape stability requires that the spring does not deform after high-frequency use, maintains the predetermined torque curve and response speed, and ensures the stability and safety of medical equipment operation.

Non-magnetic and non-toxic requirements
Some medical devices, especially MRI equipment-related products, have strict restrictions on the magnetism of springs. Stainless steel materials and processing technology must ensure that the magnetic properties of the spring meet the requirements of non-magnetic or low magnetism to avoid interference with medical imaging equipment.
Spring materials and surface treatment agents must be non-toxic and harmless, comply with relevant regulations and standards for medical devices, and ensure the safety of patients and medical staff.

Compliance with medical regulations and certification standards
Springs for medical devices must comply with a number of international and regional regulations, such as ISO 13485, FDA medical device quality management system and EU Medical Device Directive (MDR). The spring production process must have a complete quality control system to ensure product batch consistency and traceability.
Material procurement, production and processing, surface treatment, final testing and other links must strictly implement standardized processes, and third-party certification must be passed to ensure the compliance and safety of the spring.

Spring performance verification and reliability testing
Before being used in medical devices, stainless steel strong torsion double springs must undergo comprehensive performance verification, including mechanical performance testing, fatigue life testing, corrosion testing and biocompatibility evaluation.
High-standard reliability testing ensures that the spring has long-lasting stability in the actual use environment, avoiding medical equipment downtime or patient safety hazards due to spring failure.