If it's not one thing, it's another. Whether your designs are fighting off flying debris, holding their breath in a caustic chemical immersion, or surviving the rigors of extreme heat and humidity, it's your job to protect them. Following are some expert tips and tools to help your designs stand up to the harsh environments they're headed into.
Enclosed cable carriers
Energy Tubes prevent damage to cables and hoses in applications where hot chips and flying debris are common. Removable or snap-open lids enable easy cable access at each link along the fully enclosed carrier. Most of the carriers are made from a corrosion-free plastic capable of deflecting debris with temperatures up to 932° F. For even hotter environments, a more heat-resistant material is available, handling debris up to 1,500° F.
GORE High Flex cable offers extended flex life performance and maximum resistance to severe mechanical and environmental stresses. The cable is designed to deliver digital signals, analog signals, and power in demanding applications such as pick and place or linear motion, wafer manufacturing, vision inspection, robots, material handling or cranes, medical and pharmaceutical automation, printing or plotting, and storage and warehouse needs.
W.L. Gore & Associates Inc.
Extreme environment cables
Xtra-Guard cables are designed to survive the world's most extreme conditions, including heat, cold, abrasion, flexing, immersion in various chemicals, UV exposure, EMI/FRI interference, and unprotected buried runs. More than 5,000 standard constructions are available, with eight graphical icons to easily identify which environment the cable is meant to serve. All types come in a wide range of conductor counts, shielding options, and jacket colors.
Alpha Wire Co.www.xtraguard.com
Rugged coil cords
Ruggedized coil cords are designed for a range of harsh environments. Using Duralon jacketing material, these new cords are oil, chemical, abrasion, and UV resistant. Duralon is a thermo-plastic elastomer alloy with a matte finish that looks and feels like rubber and is flexible enough for high flex, C-track, rolling flex, and bend flex applications for tens of millions of cycles. It's also RoHS compliant, flame retardant, and can withstand temperatures from -24° to 105° C.
Permatex anti-seize lubricants protect mated metal parts against corrosion, rusting, galling, friction, and seizing. They also reduce wrench torque, easing assembly and disassembly of threaded, slip-fit, and press-fit connections. This inert blend of heavy-duty aluminum, copper, and graphite lubricants in a petroleum base is capable of withstanding temperatures from -60° to 1,600° F. A copper-free blend is also available, withstanding temperatures to 2,400° F.
ES series environmentally sealed encoders are designed for harsh industrial applications. A magnetic hub installed on the equipment's mating shaft leaves a small airgap between it and the encoder. This isolates the IP67-rated device from shock and vibration and makes it highly tolerant of haft misalignment, meaning no more broken couplings. The encoders are also well suited for applications involving heavy washdowns, water immersion, vibration, and debris.
BEI Industrial Encoders
AquaPruf 7600 Ultimate Series conveyors are USDA certified and designed for fast and effective sanitation in demanding environments, including ready-to-eat foods, raw protein (meat, poultry, and fish), dairy, and other applications that require high-pressure sanitation. A positive-driven USDA approved solid urethane belt ensures smooth operation in wet, humid environments, as it won't stretch and has no bacteria-harboring hinges or pins.
Rotary magnetic encoders
ED Series magnetic encoders use magneto-resistive technology to enable noncontact sensing, which allows the electronics to be shielded from the operating environment. Encapsulated construction virtually eliminates contamination even in severe conditions, including use outdoors. It also extends lifetime in high heat and humidity applications.
Measurement Specialties Inc.
DBO ✓ list
Define “extreme” for the specific application; think about temperature, pressure, chemicals, vacuum, and any sort of contamination
Keep the big picture in mind; decide on the most important aspect of product performance in the extreme environment; compromise on others
Also consider the application's performance requirements when choosing all components
“Extreme” for motors and actuators usually involves washdown environments, caustic chemicals, high-temperature and vacuum-duty settings, and areas saturated with abrasive and corrosive chemicals
“Extreme” can also refer to speed and acceleration requirements and load-carrying capacity
Keep in mind that the chemical composition of liquids can affect seals
Temperature changes can cause vacuum effects and condensation buildup
Many food-processing environments are “extreme” due to high-pressure cleaning chemicals causing metal deterioration and drastic temperature changes (e.g., a cold food process washed down with steam)
Marine and undersea applications involve saltwater exposure, which can be extremely corrosive to metal parts
Materials selection is often the most challenging part of designing for harsh environments
Proper sealing and protection of lubrication are critical design objectives in rugged environments
Materials must withstand the environment, while sealing must keep elements out of the component or machine
Dissimilar metals corrode rapidly in wet environments
Temperature extremes can cause thermal expansion or contraction, changing the fit of adjoining parts
Install motor guard splashing to protect electric motors
Use liquid-cooled rather than fan-cooled motors in the harshest environments
Consider installing an air pressure kit on the motor to prevent vacuum effects that suck moisture in as the motor cools
Understand supplier recommendations, installation references, and maintenance instructions and suggestions for all components
Remember that IP ratings are based on water; check details on coolant and oil exposures
Consider specialized materials, such as stainless steel and high-performance plastics to prevent corrosion in harsh environments
Stainless-steel housings can help vision cameras resist caustic washdown chemicals and submersion; sealed industrial connectors protect electrical cables
Encapsulating motor windings in a resin-type material protects against dielectric breakdown from moisture and chemicals
Get familiar with standards such as IP ratings, IEC classifications, and industry- specific standards
Temperature extremes can demagnetize ferrite magnets, weakening motors; consider AlNiCo or Neodymium materials instead
Consider bearings with graphite-metal compounds rather than traditional lubrication in extreme environments; high temperatures often destroy conventional greases
Use gearheads and gearmotors as intended; do not exceed ratings or misapply in harsh environments, or seals will likely fail
Consider coupling performance; extreme temperatures or hot-to-cold cycles diminish coupling response to applied forces