Reliability and durability specifics for rugged connectivity: four types of resistance

April 19, 2022 · 3 min read

To function both properly and durably, heavy-use and safety-critical applications and their interconnect system must be especially designed to withstand mechanical stress and environmental conditions without degrading power, signal, or data transmission.

 

Ruggedization methods and processes apply to the entire design, engineering, and manufacturing cycle in the creation of high-performance connectivity solutions. From choosing high-quality materials for housing, coating, plating, insulating, and sealing to protecting the insulation and conductor core against environmental challenges and chemical deterioration, material choices for connectors, and overmolding or jacketing for cables, helps maintain the integrity of the connection under extreme conditions.

 

In Connector Supplier’s April 2022 eBook entitled ‘Rugged Interconnects for Harsh Environments’, Fischer Connectors published an article on the four types of resistance that design engineers should consider when working on interconnect solutions for extreme operating conditions: 1) vibration and shock, 2) extreme temperatures, 3) corrosion and chemicals, and 4) radiation.

eBook article "Four types of resistance"

Read the full article authored by Wim Vanheertum, Product Management Director at Fischer Connectors: “Standards, Materials, and Testing for Four Types of Resistance” (pages 11-16 of the eBook). The article includes references to Fischer Connectors’ KPIs, products and customer applications, as well as two tables comprising:

 

  • the key factors that should be considered to enhance ruggedness, ensure a device’s reliable operation, and increase product life cycles to achieve less downtime and longer maintenance intervals: material mix, mechanical endurance, 360° EMC shielding, design and assembly robustness;
  • an aid to selecting the most suitable material for shells, contact blocks, and O-rings and sealing to resist mechanical stress and harsh environmental conditions in heavy-use or safety-critical applications.

Extracts:

 

Vibration and shock resistance

 

The ability to withstand dynamic stress exerted by vibration, drop, and impact is a key requirement for rugged interconnect solutions. These components must be able to perform, despite rough handling, transportation, and fluctuating conditions in the field.

 

Extremely rugged connectivity solutions are tested in compliance with the MIL-STD-202-214 Random Vibration testing standard (Military Standard 202, Method 214 and Condition I), which determines the ability of component parts to withstand the dynamic stress exerted by random vibration applied between upper and lower frequency limits to simulate the vibration experienced in various service field environments. […]

 

Extreme temperature resistance

 

High-end solutions may be tested for compliance with the U.S. Military Standard 810, Methods 501.6 (high temperature) and 502.6 (low temperature). This standard emphasizes tailoring an equipment’s environmental design and test limits to the conditions it will experience throughout its service life and establishing chamber test methods that replicate the effects of environments on the equipment rather than imitating the environments themselves. Although prepared specifically for military applications, the standard is often used for commercial products as well. […]

 

Corrosion and chemical resistance

 

Choosing the right materials and coating can protect connections against galvanic corrosion mechanisms – pitting, intergranular, or crevice. The most common coating on metallic parts is nickel chromium or thin gold-based layers applied with a galvanic or sputtering deposition process. […]

 

Products are tested in compliance with standards such as IEC 60068-2-11 Test Ka, MIL-STD-202 Method 101, and EIA-364-26. Testing includes long-standing exposure to a 5% salt solution at a temperature of 35°C to ensure that there is no impact on mechanical or electrical functionalities.

 

Chemical-proof connectivity is demanded in hospital, dentistry, and laboratory settings, as well as in food and pharmaceutical processing, devices and equipment must be regularly cleaned, disinfected, and sterilized. […] It is also required for defense & security, and oil, gas, and petrochemical application, such as downhole monitoring applications, seismic evaluation and drilling instruments, and geophysical and infrastructure maintenance devices that must resist chemicals such as aliphatic hydrocarbons, oils or fuels, greases, dilute acids and bases, detergents, and most aqueous salt solutions.

 

Radiation resistance

 

High radiation resistance is required for tasks in nuclear or contaminated environments such as handling heavy radioactive loads, performing inspections, and repairing equipment. These tasks are sometimes performed remotely with robots due to inaccessibility or the danger of radiation exposure. Radiation-resistant connectors and cables are also required when healthcare professionals sterilize medical devices and equipment using gamma irradiation (typically Cobalt 60).

 

In hospital settings, there has been an increase in medical devices and instruments made of materials, such as plastics, that require low-temperature sterilization. Some single or two-piece shell disposable connectors with housing in ABS plastic withstand sterilization with both gamma irradiation per ISO 11137-2 and EtO per ISO 11135.

 

[…]

Ruggedness

This may be of interest to you

Next news

Conference: YellowScan anounces the addition of Fischer Connectors as one of its sponsors for LiDAR for Drone 2022

April 12, 2022 · 4 min read