• New Product Additions to our on-line catalog (now over 360 products!)
• Ask the Expert "Viewer Feedback on difference between the Heavy Spot and High Spot in Dynamic Balancing?"
• What's Hot?: See Below...
• Application Focus: Infrared Noncontact Thermometers
• Intrinsic Safety: New IR Noncontact Thermometer gains FM Intrinsically Safe<?XML:NAMESPACE PREFIX = O /> Approval
• Trivia Contest: Norman Belle of BP-Texas City, TX wins the Curado Reel and All-Star Rod!!!

The MARLIN™ Condition Detector (MCD) from SKF provides a simple but extremely effective means of checking the health of a machine, measuring vibration in terms of velocity and acceleration enveloping, plus temperature to assess its operating state. By putting MCD into the hand of plant or maintenance personnel, the frequency of checking can be increased, warnings can be received earlier and plant condition experts can be freed to focus only on specific problem areas.

We've added the whole line of Raytek Noncontact Thermometers! From the MiniTemp to the Raynger ST Pro, ST ProPlus, to the top of the line Raynger MX series -  all can be found and purchased on our secure e-commerce site at www.reliabilitydirect.com.

Do YOU have a new product suggestion? If so, we'd love to hear about it. Send your product suggestions to dgallagher@ghg.net.

Answer: Wow! Several viewers had comments regarding the answer to last month's Ask the Expert. Since I value your feedback and welcome discussion, I have provided a sampling of some of the comments.

"It is my opinion, that the answer given on the Question is incorrect. Further, to imply that, on a subsequent resonance, the High Spot Only, will shift phase to Coincide with the Heavy Spot is dangerously in error.

To date, the most resonance's/critical's that I have witnessed on a large rotor coming to operating speed is four (4). The physical relationship of the rotor’s high spot and heavy spot does not change and a phase change, rarely 180 degrees, does occur as each resonance is passed; the heavy spot (force) leads and the high spot (response) lags. Each support end of the rotor often responds in a separate manner to amplitude & phase changes. Seismic instrument systems often measure the “force” during balancing.

There is a difference in degrees of freedom (DOF), and the corresponding modes of rotors. The amplification factor, A.F., by API is based on the “Q” factor principle, hoping that, at least, the top 30% of the response envelope might be obtained." Charles Jackson, P.E.

"Many machines have, due to their design, first a parallel mode resonance, then a rocking (pivoting) mode resonance in the direction of measurement. Examples are some soft mounted FD fans. Only higher will it pass or maybe get near to its first critical speed. The resulting phase shift can at times be even two times 180 getting you back at the start, i.e. the high spot is at the heavy spot, but the rotor has passed resonance's already.

In real machinery, several mixes of not only resonance influence in the vicinity, but also distribution of unbalance, can make simple statements of heavy and high spot confusing. The inexperienced fellow will maybe led astray when he sees 45 degrees or 135 degrees or anything else not so clean 0 to 180 shifts. Even more confusing when the vertical and horizontal angles to the same spot are just 5 degrees off in phase but certainly still 90 in physical life (because
one direction is still too near a resonance somewhere)." Arne Lindholm, Sweden

Wolf Campbell, P.E. responds: "I don't disagree with either of the above statements.  Recognizing that many of our readers are not experienced analyst, I wanted to point out that an understanding of basic system response (F=MA) was pertinent to balancing. 

The Raytek MiniTemp noncontact thermometer, is a pocket-sized and easy to use. MiniTemp comes in two versions: MT2 without laser and MT4 with laser. The optional accessory package includes a soft pouch and wrist strap. The MT has proven applications in HVAC, Automotive and hundreds of uses at work or around the home. MINITEMP_™—priced to fit any toolbox and small enough to fit in your pocket.

CMVP40/50 SKF Vibration Pen Plus. We have the lowest price available on this item and they are selling fast! The Vibration Pen plus operates with the press of a button, measuring vibration according to ISO standards and utilizing acceleration enveloping technology to identify a range of bearing, gear mesh and other machinery problems.

The PLT-5000 Pocket Laser Tachometer comes as a complete kit with all the accessories needed for accurate contact or laser sharp non-contact measuring.  Three different sizes of  wheels and cones and a simple to attach adaptor,  will meet most of your  contact needs, and the Laser Beam will make you non-contact measuring easier to achieve at  a greater distance. 

Application Focus: Infrared Noncontact thermometers

"An Instrument of Many Names", by Greg McIntosh-Snell Infrared Canada

Spot radiometers are often viewed by thermographers as inferior instruments. This is due primarily to the appreciable difference in cost. The technology and sophistication of many devices, however, can be strikingly similar to that used in modern uncooled thermal imaging cameras. Radiometers, spot or imaging, share the same problems of emissivity, spot size, surface reflectance, varying background temperatures - the list goes on!. With prices sometimes 1/100 of an imaging camera, spot radiometers have carved out a unique market niche and can compliment an IR imaging predictive maintenance program.

Spot radiometers can be divided into two types: hand-held and fixed-head. This article will discuss hand-held radiometers. Hand-held devices now range from under one hundred dollars to a few thousand dollars. The price variance depends on the optics and features.

Spot radiometer advocates insist that imagers are overkill for conducting temperature measurements. Thermal imaging advocates argue that spot radiometers don't give you the entire picture - that you can never be sure you have found the hottest spot. both views may be correct, depending on the application.

Radiometers can compliment an existing IR condition monitoring program to verify post-inspection repair. They are also useful for operators and general maintenance personnel to monitor a known problem (identified by an infrared survey) until the repair can be made. Always remember that radiometers are subject to the same limitations as imagers. When comparing readings of a spot radiometer and an imaging radiometer, factors such as emissivity, background temperature, and spot size should be comparable.

For additional applications notes, Infrared Surveys, Infrared Image Gallery and more, check out www.snellinfrared.com. For the best pricing on Raytek Infrared Noncontact Thermometers, check our product catalog

Factory Mutual is one of the most recognized approving organizations in North America.  Its approval is accepted in many parts of the world (checking with the end-user customer is the only way to be sure outside North America). 

Now you can get portable noncontact temperature measurements in many hazardous locations.  For most customers, the ST80-IS will be the only means to do this! The ST80-IS brings all the benefits of noncontact temperature measurement including speed, safety, convenience, to “hazlocs" (hazardous locations) . The ST80-IS can be used where flammable material is present continuously and in the presence of acetylene, hydrogen, ethylene or propane gases at a maximum temperature of 135°C (though Raytek specifies a maximum ambient temperature of 50° for reliable thermometer operation).  The rating does not apply to coal dust, grain dust, metal dust, or fibers.