SSMD replaceable tip drills include SMDT-NAL drill tips that feature proprietary diamond-like carbon (DLC) Aurora coatings. The high-efficiency replaceable drill tips are for machining aluminum alloys and non-ferrous materials. SMD holders include deep hole drilling up to 12x diameter standard, and the SMDT drill tip product lineup offers 15/32"-to-1-1/4" diameters to suit various applications.
Replaceable-tip drilling (SMDT-NAL), solid carbide drilling with DLC coating (MDW-NHGS), and DLC-coated indexable inserts (WDX) round out the lineup for aluminum holemaking.
Key benefits are smooth coating surfaces, stable chip evacuation, aluminum welding resistance to support high-quality surface finishes, and 60GPa hardness for abrasion resistance. Another advantage includes increased penetration rates due to low friction coefficient. Users can machine with 2x to 3x higher feed rates than uncoated drills, reducing cycle time and cost per unit.
Sumitomo Electric Carbide Inc. https://sumicarbide.com
Cylindrical grinding is one of the most common grinding applications used for round or nearly round workpieces, and the process can hold incredibly tight tolerances. Following some of the basic practices below will help ensure consistent high production of quality parts from your cylindrical grinder.
Work, machine centers
Clean dirt off
of work centers and out of the workpiece (part or component being ground) center holes in both spindles. Dirt on the work centers or in the work center holes will prevent centers from seating completely, causing non-concentric rotation that can result in work being ground out of round.
Work center tapers should fit snugly into the workpiece. They should pull tight into the headstock and footstock. If they don’t fit well and don’t fully contact the mating surface, they could move during grinding, potentially causing an out of round part with chatter marks.
Match the angle
of the centers in the work with the angle of the machine center. If the center hole doesn’t match the work center hole, the part may be ground out of round. Worst case scenario, the wheel could kick the workpiece out of the machine. The point – use the correct center drill, one that complements the centers that are mounted on the grinder.
Ensure the center depth
in the part is adequate and consistent. If you fail to do this, part accuracy could suffer.
Apply good quality center lube.
Failing to do this on a dead center could result in a damaged or broken center. A broken center could cause the part to be kicked out of the machine.
Place a dial indicator stand on the center of the carriage. Run the indicator back and forth along the part to check center alignment.
Regularly inspect the centers,
if they show wear, regrind them.
Pay attention to the dogs.
The work driver dog and the driving dog make it happen. They are critical to controlled part movement. Make sure they’re in good shape and tightly fastened to the largest diameter of the part. Not doing so can cause significant quality problems and can result in the part being kicked out of the machine. If the part starts to be driven by the wheel (spinners), strange part quality problems may occur. Worse case, the spinning causes the centers to fail and the part flies out of the machine.
between the driving dog and the driving pin. If this matchup is too tight, it can cause the part to be ground out of round as a result of binding.
Truing, dressing the wheel
Reconditioning the grinding wheel after a certain amount of grinding is required to reestablish the wheel form and expose new sharp grain. Dressing the wheel can be accomplished either with a stationary dressing tool or a rotary dresser. If using a stationary dressing tool, make sure it’s designed and sized for the wheel in use. The size of the wheel and the wheel specification will dictate which tool to use. A rotary dressing system equipped with a diamond roll should also be designed to complement the wheel size, wheel face, and wheel specification. Traverse rates across the wheel face, along with the depth of dress (pick amount), are instrumental in getting the wheel conditioned for the rough and finish grinding of the workpiece. A faster traverse rate across the wheel face will allow for increased material removal rates (MRR) but will negatively impact surface finish. Conversely, a slower traverse rate will improve surface finish but inhibit the MRR.
Coolant, coolant nozzles
Cylindrical grinding coolant systems are critical because they:
There are two approaches for coolant application; one applies to older style open machines that typically have grinding wheel speeds of =6,500 surface feet per minute (sfpm). They typically run flood systems with lower coolant pressure and velocity, and rely on gallons per minute (gpm) to wash grinding swarf away and keep the part cool. These older machines use a basic shovel-type coolant nozzle with a scraper blade.
Newer high-speed grinders (>8,500sfpm) with a completely enclosed grind zone can take advantage of high-velocity high-pressure coolant delivery systems. As a rule of thumb, a pump that can deliver 1.5gpm to 2.0gpm per horsepower is needed. Higher speed grinders work best when the coolant speed matches the wheel speed in sfpm. Establishing the proper time for coolant to cycle is critical and often overlooked. Plan on 5 minutes to 10 minutes; 5 minutes for water-soluble, low-viscosity oil and up to 10 minutes for higher-viscosity oil. This will help determine the size of the coolant tank. A coolant tank filled with grind sludge compromises the coolant system.
Oil is the benchmark for grinding fluid performance in most operations. It’s good for the machine as well as for the part. It doesn’t fit all applications and manufacturing environments, so options include grinding with water-soluble oil or with semi-synthetic grinding fluids.
Maintenance is very important. The system (tanks and machines) need to be cleaned and the coolant should be filtered and kept up to manufacturers’ concentration specs.
When was the last time you had the grinder cleaned and inspected Preventive maintenance is a critical part of producing consistent, quality parts. There’s nothing worse than having to run a machine that is filthy and performing poorly due to inadequate maintenance. Take time to keep the machine clean. Commit to doing the recommended service and maintenance as recommended by the machine builder.
Check the hydraulic system.
Is the reservoir full? Have the filters been changed recently?
Is the way lube system functioning properly?
Are the main bearings running at the proper temperature? Too hot indicates too tight or low levels of oil, too cool means too much clearance. Excessive vibration means bearings may be ready to fail.
Inspect the V belts.
If they are flapping around and show a lot of wear or squeal on startup, replace them. When you’re replacing the V belts, inspect the sheaves. If they are worn and the new belts sit too low in the groove, replace them. Make sure to properly align the new sheaves before installing the new belts.
Following these practices will help optimize the performance of your cylindrical grinding operations. Norton | Saint-Gobain Abrasives experts are available to help with these and other applications allowing you to improve the productivity and performance of grinding operations.
Norton | Saint-Gobain Abrasives
About the author: Phil Plainte is an application engineer at Norton | Saint-Gobain Abrasives.
Staying a bit closer to home when driving, making fewer stops per trip, and braking more aggressively when driving could all indicate mild cognitive impairment or dementia in older drivers, a study from Columbia University’s Mailman School of Public Health and Columbia’s Fu Foundation School of Engineering and Applied Science has found.
Researchers at the New York university developed highly accurate algorithms for detecting mild cognitive impairment and dementia in older drivers using naturalistic driving data, information captured through in-vehicle recording devices or other technologies in a real-world setting. These data could be processed to measure driving exposure, space, and performance in great detail. The findings are published in the journal Geriatrics.
The researchers developed random forests models, a statistical technique widely used in artificial intelligence (AI) for classifying disease status.
“Based on variables derived from the naturalistic driving data and basic demographic characteristics, such as age, sex, race/ethnicity, and education level, we could predict mild cognitive impairment and dementia with 88% accuracy,” says Sharon Di, associate professor of civil engineering and engineering mechanics at Columbia Engineering and the study’s lead author.
The investigators constructed 29 variables using the naturalistic driving data captured by in-vehicle recording devices from 2,977 participants of the Longitudinal Research on Aging Drivers (LongROAD) project, a multisite cohort study sponsored by the AAA Foundation for Traffic Safety. The participants were active drivers aged 65-to-79 years and had no significant cognitive impairment or degenerative medical conditions. Data in this study was collected from August 2015 through March 2019.
Among the 2,977 participants, 33 were newly diagnosed with mild cognitive impairment and 31 with dementia by April 2019. The researchers trained machine learning models to detect mild cognitive impairment/dementia and found that the model based on driving variables and demographic characteristics was 88% accurate, much better than models based on demographic characteristics only (29%) and driving variables only (66%).
Further analysis revealed that age was most predictive of mild cognitive impairment and dementia, followed by the percentage of trips traveled within 15 miles of home, race/ethnicity, minutes per trip chain (i.e., length of trips starting and ending at home), minutes per trip, and number of hard braking events with deceleration rates =0.35g.
“Driving is a complex task involving dynamic cognitive processes and requiring essential cognitive functions and perceptual motor skills. Our study indicates that naturalistic driving behaviors can be used as comprehensive and reliable markers for mild cognitive impairment and dementia,” says Guohua Li, MD, DrPH, professor of epidemiology and anesthesiology at Columbia Mailman School of Public Health and Vagelos College of Physicians and Surgeons, and senior author. “If validated, the algorithms developed in this study could provide a novel, unobtrusive screening tool for early detection and management of mild cognitive impairment and dementia in older drivers.”
While LongROAD participants used cars equipped with specialized recording devices, many modern cars have advanced driver assistance systems (ADAS) that feed similar data to monitoring systems, raising the possibility of mass-market implementations of tracking systems.
AAA Foundation for Traffic Safety
Columbia University Mailman School of Public Health
Ford is teaming up with HP to reuse spent 3D-printed powders and parts, closing the loop and turning them into injection-molded vehicle parts. Sustainability is a priority for both companies, which through joint exploration led to this unlikely, Earth-friendly solution. The resulting injection molded parts are better for the environment and don’t compromise durability or quality.
Recycled materials are being used to manufacture injection-molded fuel-line clips on F-250 trucks. The parts have better chemical and moisture resistance than conventional versions, are 7% lighter, and cost 10% less. The Ford research team has identified 10 other fuel-line clips on existing vehicles that could benefit from powder recycling.
“Finding new ways to work with sustainable materials, reducing waste, and leading the development of the circular economy are passions at Ford,” says Debbie Mielewski, Ford technical fellow, Sustainability. “Many companies are finding great uses for 3D printing technologies, but, together with HP, we’re the first to find a high-value application for waste powder that likely would have gone to landfill, transforming it into functional and durable auto parts.”
HP 3D printers are already designed for high efficiency, with systems that minimize excess material and reuse a greater percentage of the powders put into them. Working with Ford, which uses HP’s 3D printing technology at the company’s Advanced Manufacturing Center, the team created a solution that produces zero waste.
“You get more sustainable manufacturing processes with 3D, but we are always striving to do more, driving our industry forward to find new ways to reduce, reuse, and recycle powders and parts,” says Ellen Jackowski, chief sustainability and social impact officer, HP. “Our collaboration with Ford extends the environmental benefits of 3D printing even further, showcasing how we are bringing entirely different industries together to make better use of spent manufacturing materials, enabling a new circular economy.”
Ford is developing new applications and using multiple processes and materials for 3D printing, including filaments, sand, powders, and liquid vat polymerization. The company already employs 3D printing for a variety of low-volume commercial vehicle parts, as well as fixtures used by assembly line workers.
“A key to achieving our sustainability goals and solving the broader problems of society is working with other like-minded companies – we can’t do it alone,” Mielewski adds. “With HP, we defined the waste problem, solved technical challenges, and found a solution in less than one year, which is something in which we all take pride.”Ford Motor Co. https://www.ford.com