Tuesday, March 31, 2009

Casters for High Heat Applications

Diane here today, to share with you another interesting problem-solving situation, this time with casters. Because casters are such ubiquitous component--I mean, there are so many types of equipment that need to roll--they are employed in every application imaginable.

The situation of which I speak happened to be a bakery where exposure to oven temperature was taking a terrible toll on cart wheels. In fact, they were consistently failing within a month. Part of the problem was the combination of heat and flour getting trapped in the raceway of the casters, which would cause the wheels to seize up and become immobile.

The solution was the high-temperature PHN caster. The wheels of this caster are made of a reinforced heat resistant phenolic resin with heat-resistant ball bearings, and are able to withstand continuously high temperatures up to 500°F (briefly to 572°F). To further alleviate the problem, the manufacturer added a special heat-resistant silicone O-ring to keep food and other particles from entering the raceway, which you see here. These solutions kept the carts easily mobile and also eliminated the need for maintenance.

We offer these casters in fixed and swivel versions, and the wheels themselves are available upon request. And going back to my first comment about ubiquitous casters: we have a huge selection of casters for any application, and more types available upon request. See them all in our Section 14!

And I hope you will join me and use the word "ubiquitous" in conversation today!

Friday, March 27, 2009

Everybody Shares, Everybody Wins

If you, like me (Diane), are a regular reader of any blogs or sites in the design engineering field, odds are by now you have run into Kish, Stephen and Bob.

These three gentlemen are the stars of a new online show called "3 Dudes Gone 3D," sponsored by SolidWorks. I have lost count of the number of advertisements I've encountered for this show, and I gotta say, as a "marketing babe," I'm impressed by the media splash.

I also like the three characters--the egotistical genius Kish, the enthusiastic newbie Stephen, and the old-school, down-to-earth Bob. They all merit the coveted title occasionally bestowed by J.W. Winco, "Engineers We Love." Check them out on the webisode below:

What we also love is the general theme of SolidWorks' campaign: as Bob puts it, "everybody shares, everybody wins." SolidWorks is referring to the tools they provide to their user community to share and co-opt knowledge and designs. We are totally in favor of that outlook, and it's one reason why we created this blog. J.W. Winco possesses some serious expertise in the field of utilizing standard components for efficient and effective design, and we want to share what we know. So we're putting it out here on our blog and our Web site, for customers and non-customers alike.

In a similar vein, there's our free CAD offering. A few years back when we invested the time and money into launching this aspect of our Web site, we talked about the possibility of users "taking advantage" of our models. Obviously, by putting them out there for free, we were sharing the design of our parts with people who might never become customers.

But this is 2009: sharing information is what it's all about. We also feel that if a company demonstrates how valuable it can be as a design partner, customers will come regardless.

And when customers team up with us, as Bob says, everybody wins.

I'm looking forward to upcoming webisodes with him and his pals in their overflow trailer. And they are welcome to download our CAD anytime!

Wednesday, March 25, 2009

The Perfect Solution for Food Service Equipment

Greetings from a new poster on the blog! I'm Tony Cavadias, the North American Sales Manager for J.W. Winco. I'm writing to share with you an interesting anecdote about how we were able to work with a customer to solve their application problem.

A manufacturer of food service equipment was purchasing a phenolic resin knob from us. They had experienced some problems with this particular knob, due to the brittleness of phenolic resin and the demands of the application. So we suggested that they look at our GN 6336.5 knob as a replacement. This knob is glass-filled nylon plastic with a molded-in stainless steel stud. This type of plastic bears up much better than phenolic when exposed to stress.

The new knob was tested and approved by the customer's engineering team. However, a question arose about the "open backside" of the GN 6336.5: the engineers were worried that it would prevent the knob from meeting NSF (National Sanitation Foundation) requirements, and to be certain of its suitability, expressed their wish for a knob with a closed back that would prevent potential trapping of food scraps.

We contacted our supplier to discuss options, and learned that they were capable of supplying us with the same knob with a closed back that would eliminate any potential problems completely. Our customer approved this version and now had a complete solution to their application problem.

Meanwhile, the customer was working on a new piece of equipment, and decided to incorporate the closed back knob on that product as well to maintain uniformity of look throughout their product line.

One of the most satisfying parts of my job is working with customers like this, who are having problems finding the perfect component for their application. Having a broad selection of options and knowing the advantages of each, I'm able to perform a service for the customer that augments the expertise of the engineering staff. Meanwhile, our good relationships with our suppliers enable us to offer even more product options.

Who knew selling machine components could be such exciting stuff?

Monday, March 23, 2009

Tubular Arch Handles

Diane here, to introduce you to another of our cool new products: the GN 666.4 metric sized Tubular Arch Handles with tapped inserts for mounting.

Available in aluminum or stainless steel, these handles are an advanced development of the typical tubular handle with straight tube, and are RoHS-compliant. The handle legs are matte black glass filled nylon plastic (polyamide) with zinc-plated steel tapped inserts for mounting. Cover caps are matte black nylon plastic.

Tubing on the aluminum versions is available with a black pebble-coated, or natural anodized finish. The tubing on the stainless steel versions has a matte polished finish. Metric size fasteners and kit packaging are available upon request.

Thursday, March 19, 2009

How Would Nature Solve Your Design Problem?

Greetings from me, Diane, reporting from Wisconsin where robins have arrived, trees are budding, and we recklessly hope to avoid more snow. With thoughts turning to nature around here, I thought I’d talk about a very cool tool I just discovered.

It's called "Ask Nature" and is an online database sponsored by the folks at Autodesk, and operated by The Biomimicry Institute. Biomimicry is a new science (so new my spellchecker doesn't recognize the word) that looks to models in nature to inspire ingenious, sustainable solutions to human problems. As the site puts it, "It’s amazing what a 3.8-billion-year head start can do when it comes to problem solving."

To see how the site works, I posed a design problem. How might you design feet for a table subject to a lot of vibration, that would make it stay in one place regardless of the type of surface it stands upon? I mean, let's say this table might be placed on rough carpet, or it might be placed on smooth hardwood or tile.

So I searched on "rough or smooth" and the database turned up this story:

Feet of insects adjust to rough or smooth surfaces by engaging either claws or adhesive foot-pads.

"Researchers Bert Holldobler and Walter Federle have studied how insects can adhere to both rough and smooth surfaces. They discovered that when an insect walks, two claws at the front of each foot grip the surface and then begin to retract. If the surface is rough, the claws engage and the insect scrabbles along. If the surface is smooth, the hinged claws retract further and adhesive foot-pads protrude between the claws."

Immediately I'm picturing some sort of spring-loaded claws for the feet, which could retract, exposing non-skid rubber pads. Brilliant! Obviously an even more direct application, and one that I read has actually been used, is the design of feet for walking robots.

[I did notice that the Ask Nature site has a few "bugs," pardon the pun, but seeing as it was just launched last November, I'm sure they are still tweaking it.]

I have to agree, nature over time has figured out millions of clever, workable, and sustainable "machines" (i.e. creatures) that do nearly everything we humans would like our machines to do. It only makes sense to look to the natural world for designing tips.

I really have only one argument with nature's way: Why must winter be so long?

Tuesday, March 17, 2009

Quick-Release Fasteners

It's Diane, and having talked last time about vibration-proof fasteners, I thought I'd tackle the opposite concept: quick-release fasteners. Because here's the thing: Sometimes you want your fastener to hold, and sometimes you want it "easily persuaded to let go."

This presents a new design challenge for components, and that is to make them quickly and easily movable or removable, without sacrificing some worthwhile fastening properties. The examples I'm sharing with you today use various techniques to achieve this.

Let's start with the very simple GN 6303.1 knurled nuts. These are used in applications where the nut has to be completely removed after the releasing operation and refitted very rapidly for re-clamping. It's based on the DIN 6303 knurled nut, with the modification you see in this line drawing. To mount the knurled quick release nut, you tilt it over the threaded spindle, slide it down the spindle to its final position, then align the nut with the threaded spindle by straightening it from the tilted position. This meshes the two components. Only a fraction of a rotation is needed to achieve clamping.

A similar principle is employed in the design of several of our hand knobs. The GN 6336.3 is a nylon plastic hand knob with a steel hub, used in applications where the knob has to be completely removed and refitted very rapidly for re-clamping.

Our LMAQ knob is an all-plastic alternative, made of thermoplastic in a nice modern design with good shock-resistance.

And lastly, for environments requiring stainless steel, J.W. Winco developed the WN 5335.5 quick release nine-lobed hand knob. This one's a beauty.

Quick-release capabilities can also be achieved using other techniques in the design of the part. For example, our GN 6333 quick-release hex nuts are manufactured so there is no "locking" of the thread. Unlike the items previously discussed, these nuts slide down the spindle without tilting the nut. Once in the final position for clamping, the upper hex part of the nut is pressed down over the split nut so that it locks the threads to the threaded spindle. Then the nut can be tightened by using a wrench, securing it into its locked position. The nut can then be removed by depressing pins on the sides of the nut that release it from its locked position, allowing the nut to be quickly removed by sliding it up from the threaded spindle.

For another type of quick-release technology, check out our GN 124 quick-release pins. The balls in these pins are spring loaded, but not rigidly, so they have a relatively low axial holding strength. The illustration shows the type of application where this kind of pin can be used, allowing for quick fixing and removal.

You know, although many of the components we sell at J.W. Winco seem simple and basic, it never ceases to amaze me how significant are the subtleties of their design. This is why our Technical Sales Associates are so well versed in how to find the appropriate part to fit a customers' application.

Friday, March 13, 2009

Vibration-Proof Fasteners

Diane reporting, and today I’m quite intrigued by the issue of fasteners and vibration. On its face it seems like a simple question: How do you insure the fasteners won’t loosen in an application that is prone to vibration? In actuality, it seems if you put several engineers in a room to discuss the question, you may need a vibration-proof room to handle all the discussion that ensues.

Along with proper torque, common possible solutions boil down to these:
* Use of washers to lengthen the ratio of clamped length
* Threadlockers
* Safety wire (aka lockwire)
* Vibration-proof fasteners

There doesn’t seem to be too much controversy regarding threadlockers. These are chemical adhesives applied to the fastener, most notably Loctite. Keep in mind however that Loctite acts like a lubricant when wet and can affect torque. It also is not appropriate for high temperature situations.

Safety wiring, according to my reading, can be anything from completely useless to the ideal solution. This page offers a nice set of illustrated instructions on how to safety wire bolts on a motorcycle, by way of example. Obviously one “con” of this approach is the time it takes to do. Also, proper technique or lack thereof are huge factors. And adding holes to your fasteners will reduce their integrity.

Fasteners themselves can be designed to cope with vibration. For one thing, you can look for bolts and screws with nylon-patches pre-installed. These will hold up for approximately five cycles of removal and reuse. J.W. Winco offers a number of spring and ball plungers with locking nylon patches, so I include one here by way of illustration.

Our technical section includes some excellent information on the polyamide locking patch (PFB) as well as the micro encapsulation precoat 80 patch (MVK), designed for thread locking.

Fasteners designed specifically to cope with vibration include hex nuts with nylon inserts, jam nuts, lock nuts, slotted hex nuts, tooth lock washers, lock washers and spring washers. Again, there is some debate as to the efficacy of these depending upon the application. J.W. Winco sells a broad array of vibration proof fasteners in metric sizes, viewable in our catalog Section 19.

For an animated and “vibrating” debate on this topic, see this thread on http://www.eng-tips.com/. Which, by the way, is an excellent source of forums on all aspects of engineering,

Wednesday, March 11, 2009

A Toolbox for Engineers

Diane here, with an addendum of sorts to the previous post about online resources for engineers. But first, the back story of how I found that resource.

Recently one of our Technical Sales Associates was assisting a customer on the phone. This gentleman asked for the density of one of our parts. Our associate told him she’d be happy to find out from the manufacturer what the density was.

As this is not a question we get every day, I was trying to recall from high school physics exactly how one derives density. Something with mass and volume, right? (Well, I’ve told you before I’m not an engineer.) So naturally I headed for the Web to seek a refresher course in density. In the process I found another very handy online resource for engineers, a site called The Engineering ToolBox.

The Engineering ToolBox is a tremendous resource for information organized by topic (such as basics, electrical, material properties, thermodynamics, etc.) and searchable by word. From the Cauchy Number (“a dimensionless value useful for analyzing fluid flow dynamics problems where compressibility is a significant factor”) to the input horsepower to the electrical motor for a pump or fan, it’s right there for you. The left hand column has a number of conversion calculators for all kinds of measurement, as well as an online scientific calculator, the cyber-equivalent of those Texas Instrument status symbols sported by the kids in my high school physics class.

Now that I’ve discovered The Engineering ToolBox, I can impress my friends at cocktail parties by talking about the Cauchy Number, and saying things like, “Density, you know, is the gravitational force acting on the body mass of an object.”

This is probably still not going to convince anyone I’m a real engineer, of course.

Monday, March 9, 2009

Online Resources for Engineers

Diane reporting today, and here to share some great information compiled recently by our friends at Design World magazine. They came up with a list of the best sites for engineers who are searching both for products and for technical information. I thought I’d share some highlights, along with my own recommendations.

Google - Of course this is the search engine we all use most often, and while it doesn’t index everything available via the Web, it is comprehensive and reliable. It’s also the online source most engineers use when looking for component sources.

Google Scholar - This specialized version of Google indexes scholarly works, and therefore can find abstracts, articles, and papers with technical information.

Scirus – This engine is considered by many to be the most comprehensive science search engine on the Internet. Use it to find reports, articles and journals.

Intute – This is the science section of a UK-developed search site that includes pages organized by topic and ranked by human subject experts.

Turbo10 – Turbo10’s claim to fame is that it searches specialist databases that are not indexed by traditional crawler-based engines like Google.

TechXtra – Like Turbo 10, this search engine has access to the “hidden Web,” and specializes in engineering, math and computing.

Scitopia – This is a vertical search portal created by 21 technological societies. It will lead you to research and scholarly data, journal content, and conference papers.

Open J-Gate – This site allows you to search the contents of 4,000 scientific journals.

Google Blog Search – Often you can find the answer you seek in the experience of others, and blogs are a great resource for that. This engine specifically searches blog content.

Google Books – With 7 million books and growing, this is a massive library! You can search the actual text of those books with this tool.

Engineering Village – This site is fee-based rather than free, but is a highly recommended resource for engineers. It combines search tools and content sources, including key engineering databases. Also a good source for finding parts suppliers.

ThomasNet – This site is the top clearinghouse for information on sources of components and other industrial providers. Search the database for a supplier, find catalogs, or download CAD models here.

Of course, the key test of the value of a Web site is if it can find J.W. Winco as a search result, and most of these can! ;-)

Thursday, March 5, 2009

Ergostyle® Zinc Die-Cast Adjustable Levers

This is Diane, with another featured product recently offered by J.W. Winco: GN 602 series Ergostyle® Zinc Die-Cast Adjustable Levers.

These RoHS-compliant hand levers are the result of modern industrial design, and are ideal wherever parts have to be clamped in a confined space or in a particular lever position. The slightly arched shape of the lever gives the operator a comfortable and safe grip. The insert is connected to the lever via serrations, which can be easily disengaged.

Pulling the lever upwards disengages the serrations, allowing it to be swiveled to the ideal clamping position. When the lever is released, the serrations automatically re-engage.

Available in a variety of inch and metric sizes, the levers come in tapped, blind bore, and threaded stud types. The handle is zinc die-cast and the insert, screw and spring are steel with black oxide finish. A matte black, pebbled finish is offered as well as orange, red and silver; special colors are available upon request.

And if you need special modifications, remember we can do secondary machining such as cross holes, set screw holes, and threaded studs.

Wednesday, March 4, 2009

Virtual Testing

Diane back today, and I wanted to share with you a cool story I ran into in the February issue of NASA Tech Briefs. I posted recently about virtual machine construction, and this article took the matter a step further: the virtual testing of those virtual prototypes.

The example discussed was "virtual shaker testing," using software from a company called LMS. Using this process, a part or device in digital form is tested in virtual reality. LMS's Virtual.Lab offers a complete, integrated software suite for testing for structural integrity, noise and vibration, system dynamics and durability.

The benefits to this approach are pretty obvious, but I think it's so cool I'll just run through them here. You don't need a prototype to be physically constructed in order to test it. Nor is your prototype damaged or destroyed by testing. You can quickly and easily tweak the prototype and retest it as you go, until the best possible configuration is achieved. All this saves time and money, as well as making testing safer in the case of machinery that is potentially dangerous to test; for example, aerospace, automotive products, and medical products.

In this illustration, taken from a brochure about the LMS's software, a fixation bracket is tested on a virtual shaker table. Stress patterns show up on the digital bracket. In fact, the software can be used to simulate more appropriate and accurate stress than a real life shaker table would do. Different types of combined stress can be executed simultaneously, such as the start-up phase of the device combined with random stresses inherent in usage.

For all the specifics on virtual shaker testing, that brochure (in pdf) can be downloaded free from this link.

Addendum to post, 3/6/09: Our Chief Technology Officer, Robert Winkler, adds, "I use virtual testing...actually SolidWorks has an add-in called SolidWorks SimulationXpress (formerly Cosmos Express). Whenever I design something new or I draw up something a customer has spec’ed out, and if the need is there, I push it through SimulationXpress. It is a force and load stress assessment tool to analyse the structural fail (or potential) failure points. It also does a simulated flex stress, and as it does this animation it shows your potential fractural issue points. SimulationXpress is included with SolidWorks Standard, Pro and Premium."

So we are already using this technology here at J.W. Winco in our R&D and our design service to customers!