Ethan WeikleengetClick image to enlargeby Ethan Weikleenget

Grinding wheel flanges and personal safety

Even experienced grinding wheel users may not realize the importance of wheel mounting procedures and equipment as they relate to personal safety. To illustrate this, consider an analogy of wheels on a car, which are similar to mounting flanges on a grinder in that both transmit rotation by linking a shaft to an outer component (namely, to a tire or a grinding wheel). Imagine you are driving a car at 160 km/hr and you suddenly sense the wheels are damaged or not properly attached. Danger! Any driver would rightly feel unsafe and stop
the car immediately.

Now imagine you operate a grinder whose grinding wheel rotates at 160 km/hr (45 m/s or 8,860 sfpm), and you stand beside that wheel for hours at a time. Would you feel safe if you had reason to suspect that the mounting flanges were damaged, poorly attached, or improperly designed?

Click image to enlargeThe stresses produced by poor mounting procedures and damaged equipment can cause wheels to break, and broken wheels can cause serious injuries to operators and bystanders. Like car owners, grinding wheel users should regularly check their equipment to detect mounting problems before they develop into more serious hazards. Useful guidelines for proper procedures and equipment are given in the American National Standards Institute Requirements for the Use, Care and Protection of Abrasive Wheels (more commonly, ANSI B7.1). For example, the ANSI B7.1 requirements
for flanges cover:

Flange Design
• Flange shapes and dimensional requirements differ by application.
• Flange material must meet given strength and rigidity standards.
• Most flanges require recesses to concentrate the clamping pressure on a precise area.
• Some flanges require undercuts to provide extra clearance near the bore of the grinding wheel.
• Flange pairs generally must be uniform in diameter to prevent cross-bending stresses.

Flange Condition
• Flanges must be maintained in good condition with respect to flatness, surface condition (free of burrs and foreign particles), balance, wear, and truth.
• Flange flatness should be checked with and without grinding wheels mounted.
• New blotters (compressible washers) must be used every time a wheel is mounted, unless they are attached to the wheel by the manufacturer.


Blotters are necessary for safe mounting. Besides their primary benefits such as preventing the flanges from slipping and protecting against wear from the abrasive wheel, they have another valuable function. Since blotters are compressible by design, they take on impressions from the flanging surfaces that provide information about the mounting situation. So next time you perform a wheel change, check the used blotter for the following:
• Complete Contact –the blotter should show evidence of complete and consistent flange contact over the entire bearing surface.
• Concentrated Pressure –the blotter impressions should be even and not indicate concentrated or insufficient flange pressure.
• Evidence of Movement –the blotter should display no signs of slipping or other movement of the grinding wheel inside its flanges. Scratches, tears, or other wear marks may indicate there has been movement.

Careful design and periodic inspection of grinding wheel mounting equipment and procedures are critical to a safe operation. Additionally, examination of used blotters is an easy and valuable way to check for potential mounting problems that can develop into a serious hazard if not addressed. Be aware of the risks associated with poor mounting, and be proactive in your approach to abrasive safety. SMT

Ethan Weikleenget is senior product engineer with Norton|Saint-Gobain.

 

US firm expands cryogenic machining technology

5ME, a Warren, MI, which specializes in manufacturing services and software to improve efficiencies, has secured rights to cryogenic machining technology by acquiring 51 patents from Creare, a supplier of cryogenic systems and fluid dynamics.

GM Canada commits to job support for Oshawa assembly workers

GM Canada says it plans to provide financial support to the close to 3,000 workers who will be losing their jobs at the Osahwa, ON, assembly plant when it closes in 2019.

Stringer Success

Article by Kip Hanson | Photos by Deny Cardinal

Quebec aerospace manufacturer expands aluminum machining capabilities with extrusion mill

Simultaneous five axis with a range of features

The Methods MB 450U Bridge-Type machining centre from Methods Machine Tools Inc., is a Taiwanese made model that offers five axis simultaneous machining. The Fanuc 31i-MB5 control enables full five axis precision machining of challenging parts, significantly reducing the need for multiple setups.

Charged for growth

by Mary Scianna

The Problem: Missing out on part families from existing customers

The Solution: EDM technology to capture more business

Ontario shop carves aluminum machining niche with EDM technology

CAD/CAM supplier celebrates 25th anniversary

CAD/CAM supplier In-House Solutions, Cambridge celebrated its 25th anniversary recently with a one-day open house on May 10.

Mazak partners with MachiningCloud

Mazak and MachiningCloud have partnered together to bring enhanced data management to machine shop floors.

High Speed Machining Know-How

by Andrei Petrilin

Tool accuracy plays an integral role in high speed machining success

Multifunction five-axis machining centre

Makino's iGrinder five-axis horizontal machining centre combines grinding, milling, drilling, and tapping, all on the same platform. Watch it in action.

Watch for the Piranha

by Kip Hanson | photos by David Afriat

Quebec cutting tool manufacturer achieves new levels of precision and productivity

8 Insert Failures

by Don Graham

Spotting and preventing common insert failure modes

WATCH: Engineering projects you don't want credit for

WATCH: World's funniest engineering fails. Who approved these blue prints?

Will reshoring offshore again?

India has a problem and it's looking at manufacturing to fix it. The country's services sector, which has driven economic growth in that country for years, is shrinking and some are proposing India refocus its efforts on manufacturing

North American Robotic orders surge in 2014

Robot orders and shipments in North America set new records in the first nine months of 2014, according to Robotic Industries Association (RIA), the industry's trade group.

Stay In Touch

twitter facebook linkedIn