Rugged Connectors in Practice: Comparing Industry Standards to Real-World Conditions
MIL-Spec and technical standards often represent basic benchmarks for connectors. However, when real-world applications demand performance that surpasses these benchmarks, the need arises for more advanced, resilient, and enduring components.
Clients in aerospace, defense, and industrial sectors consistently escalate their expectations for rugged and harsh environment connectors. They require components that not only fulfill existing standards but are also engineered with a vision of enduring future conditions, particularly in terms of longevity and data transfer capabilities. Customers are seldom satisfied with "adequate" performance; their objectives tend toward superior performance and connectors capable of accommodating technological advancements.
In the contemporary marketplace, the technical and MIL-Spec standards might fall short of addressing the practical performance needs. Generally, these standards serve as starting points for compliance, and the true demand is for connectors that exceed standard performance levels. Components that are pioneering, quicker, and more durable are crucial for satisfying these advanced expectations.
For the manufacturers of these connectors, the challenges include countering various environmental factors such as moisture, extreme temperatures, corrosive substances, and fine particulates like sand. These variables may act alone or synergistically. The connectors also have to endure extensive periods under a broad range of vibrations, which is particularly vital in sectors like aviation, rotorcraft operation, mining, and oil drilling.
Another aspect of stress comes from maintenance operations. During routine checks, component replacements, or upgrades, connectors go through numerous cycles of disconnection and reconnection. Each cycle poses a risk of accidental damage to the connector.
Furthermore, there is a growing demand for connectors that can ensure stable, high-speed data transfer with exemplary signal integrity, even in the most adverse environmental conditions, including extreme temperatures and vibrations.
High-Temperature Connectors (The Higher the Temperature, The Better the Connector)
High-temperature settings pose significant challenges for duty-grade connectors designed for severe environments. Such connectors necessitate intricate design and specialized materials to fulfill stringent requirements that ensure dependable signal transmission during vital operations in high-heat conditions. Usage scenarios for these connectors span across high-temperature areas typical to engines, oil and gas exploration, geothermal activity, solar energy, power generation, and military/defense sectors. Frequently used interfaces include probes, signal transmission devices, thermocouples, and pressure sensors.
Often, high-temperature connectors are designed to fit within industry-standard shells such as MIL-DTL-38999 or EN2997, made to accommodate two or three contacts. The widely recognized MIL-DTL-38999 standard specifies a temperature range from -65 °C to +200 °C.
Some connectors that are in line with EN2997 standards can handle maximum temperatures up to 260 °C. There are manufacturers who claim their high-temperature products can withstand up to 300 °C. A prominent manufacturer of bespoke connectors even provides an ultra-high-temperature EN2667 variant, which endures continuous duty at 405 °C, peaks at 450 °C (considerably higher than the top limit of the MIL-DTL-38999 specification), and surpasses the regular EN2667 specification by 145 °C.
High-temperature connectors require materials that can both endure intense heat and maintain their shape and strength under such conditions. Titanium is an ideal choice for the shell material because it excels in corrosion resistance, electrical conductivity, and is lightweight, which are critical traits for components exposed to elevated temperatures. While steel shells with plating are an option, their longevity can be compromised by heat or mechanical damage like scratches. Unlike plated materials, where a scratch could expose the underlying material to corrosion, titanium's endurance remains intact even when scratched due to its inherent resistance across the entire material.
Internally, these connectors often use high-temperature ceramic inserts, providing not just heat endurance but also dimensional stability. However, ceramics can be prone to crack under vibration or sudden impacts and might not be ideal in environments with high vibration. The most effective high-temperature connectors are those that employ advanced composite ceramics specifically engineered to withstand both vibration and high temperatures.
For optimal functionality, high-temperature connectors must ensure seamless, high-speed data communication between transmitting and receiving units. While high-performance connecting cables that can maintain fast data rates over extended distances are vital, the connectors themselves play a pivotal role at both ends of the communication line. The overall design of these connectors—including their temperature thresholds, termination methods, and resistance to electromagnetic interference and environmental challenges—cumulatively define their quality, not merely one isolated specification.
MIL-DTL-38999 Harsh-Duty Connectors
The MIL-DTL-38999 specification is ubiquitous among harsh environment connectors, applied widely across aerospace, military, and select industrial sectors. The design, which has stood the test of time, dates back 75 years. It's a confident bet that connectors adhering to the MIL-DTL-38999 standard will continue to be produced well into the future, extending past the lifespan of current readers.
The success of the MIL-DTL-38999 lies in its uniform features across a spectrum of connector sizes. These features include interface design, mounting, and technical specifications regarding conductivity, electromagnetic interference protection, and resilience to environmental stressors. Common base materials such as steel, aluminum, or composites, along with specialized finishes for both cosmetic and protective purposes, ensure these connectors meet the needs of a vast array of harsh and rugged applications.
In essence, the MIL-DTL-38999 connector is a reliable, industry-standard component, recognized for its array of tested and proven characteristics, offering consistency and dependability to users across various demanding sectors.
The robust features that define the 38999 connector as an exceptional choice for extreme conditions may introduce certain trade-offs and constraints for specific uses. Nevertheless, strategic engineering ensures its sustained relevance in harsh applications.
For instance, the sturdy build of the 38999 may render it too bulky for aircraft where weight is a critical concern. This problem can be addressed by adopting composite material shells for the connectors, which can cut down the weight by approximately 20%. While this reduction might seem trivial on a per-connector basis, the cumulative impact is significant in large aircraft housing hundreds of connectors. Composite connectors are increasingly being recognized in the market for their effective balance between lightweight design and robust performance.
In terms of data transmission, the standard 38999 connector presents limitations; although it can support a respectable 1 Gb/s data rate, the evolving demand for higher speeds is being met by newer designs. Small multipin connectors and dense signal connectors have emerged, which can sustain data rates up to 10 Gb/s within the size constraints of 38999 shells. These high-density connectors surpass the traditional 38999 models in tough environments where high-speed data transmission is crucial.
Rugged Performance with Serviceability
The replaceability of a harsh environment connector is as crucial as its performance specifications. Fast and efficient repairability is vital, especially in commercial aviation where flight schedules are strict. Delays and disruptions have a compounding negative impact, including significant financial repercussions.
The industry lacks a standardized approach to repairs, and practices can vary among manufacturers. Some assemblies are not amendable to field servicing and necessitate the exchange of the entire cable. This is feasible for certain defense applications where on-site repairs are impractical. Conversely, for industrial or commercial aviation, where access might be challenging or cable lengths preclude easy replacement, field-serviceable connectors are the optimal solution. However, various manufacturers may require unique parts and specialized tools for repairs. The most practical designs are those that permit repairs using common avionics crimping tools and standard contacts.
An often overlooked yet vital aspect of serviceable connectors is whether they need a heat source, such as a heat gun, for shrink tubing or curing materials. In passenger aviation, repairs that involve heat necessitate vacating the aircraft and relocating it to a secure location with firefighting resources at the ready. Thus, a seemingly straightforward connector repair may become a complex and time-consuming process. Connectors that allow crimping without these additional risks streamline repair procedures.
Selecting Harsh Environment Connectors
When choosing connectors for demanding environments, one must contemplate the following attributes for long-term application:
- Durability
- Weight consideration
- Data capacity versus size
- Potential for future technological integration
- Signal preservation
- High-temperature tolerance for peak and future performance
- Balance of cost and performance
Deciding on connectors for extreme conditions goes beyond merely adhering to standard specifications at the lowest price point. The most affordable option may satisfy basic requirements but likely won't hold up against extended real-world demands. While more costly on an individual basis, some connectors offer superior overall functionality and room for technological growth. Therefore, it's wise to aim for enhanced performance in connector design. Choosing the most efficient connectors based on comprehensive performance, rather than just minimum standards and price, will better equip one to address future necessities.
Harsh environment connectors are designed to withstand extreme conditions, such as high temperatures, vibration, and exposure to chemicals. They are used in a variety of applications, including oil and gas, military, and industrial automation.
BonChip Electronics, a trusted distributor of harsh environment connectors, offers a wide range of products from leading manufacturers. We can help you choose the right connector for your application and provide expert technical support.
When choosing a harsh environment connector, it is important to consider the following factors:
- The environment in which the connector will be used:
- Consider the temperature range, humidity, vibration, and exposure to chemicals.
- The type of signal that will be transmitted through the connector:
- Consider the voltage, current, and frequency of the signal.
- The size and weight of the connector:
- Consider the space available for the connector and the weight of the cable.
- The cost of the connector:
- Consider the initial cost of the connector as well as the cost of maintenance and replacement.
Harsh environment connectors are available in a variety of standards, including:
- MIL-STD-83513: This standard specifies the requirements for connectors used in military applications.
- IEC 60603-2: This standard specifies the requirements for connectors used in medical applications.
- API 6A: This standard specifies the requirements for connectors used in oil and gas applications.
It is important to note that these standards are not always sufficient to ensure the performance of a connector in a real-world application. For example, a connector that meets the requirements of MIL-STD-83513 may not be able to withstand the vibration and chemicals present in an oil and gas application.
When choosing a harsh environment connector, it is important to consult with an expert to ensure that you select the right connector for your application. BonChip Electronics has a team of experienced engineers who can help you choose the right connector for your needs.
In addition to the factors listed above, there are a number of other considerations that may be important in the selection of a harsh environment connector. These include:
- The mating cycles of the connector:
- Consider how often the connector will be mated and unmated.
- The shielding requirements of the connector:
- Consider the level of electromagnetic interference (EMI) that the connector will be exposed to.
- The safety requirements of the connector:
- Consider the need for the connector to be arc-proof or explosion-proof.
BonChip Electronics can help you choose the right harsh environment connector for your application. We offer a wide range of products from leading manufacturers and have a team of experienced engineers who can provide expert technical support.
Contact BonChip Electronics today to learn more about our harsh environment connectors.
