LONGO
The Largest Independent Electrical-Mechanical Sales and Service Company in the Northeast
THE LONGOLETTER
VOLUME 5                        ISSUE 3                        OVER 65 YEARS                        FALL 2014
Joseph M. Longo
President

Service through Knowledge

For years, we offered seminars to our customers on a variety of subjects from the basics of electricity to understanding pump curves. We would have anywhere between 25 and 40 attendees depending on the subject and of course the time of year. The day would start with coffee and rolls as the various people met and talked, networking (before the name), lunch and then a solid Q&A session. Not only did the presenter answer a lot of the questions, but people in the room began to offer up their own examples of similar situations. As you can read in this issue these formal seminars have evolved into "Lunch and Learns".

The idea was to provide information because our tag line "Service through Knowledge" meant the more you, our customers, understood your equipment and what it takes to maintain it, the better off you would be. Our job is to make sure we are continuing to keep up with the best practices and latest technology so that we are able to convey the knowledge in a practical and efficient manner.

Today learning is a luxury, an expense and often inconvenient. Although Longo has a wealth of talent and experience in house, technology continues to improve. So before we can provide you with knowledgeable answers to your problems we better know what we are talking about.

To do this we try to take advantage of manufacturers' training sessions, whether it is on gearboxes, pumps, air compressors, etc. More often than not our people learn not only the specifics of the equipment, but even some "tricks of the trade" when it comes to tear downs and repairs. Another aspect is certified training. Many engineering firms and other third party approval companies, who act as clearing houses for bids and projects, require more than a resume of projects to be considered for a specific job...you need a pedigree.

For example Longo has become NETA certified. The InterNational Electrical Testing Association (NETA) is an organization that serves the electrical testing industry by offering accreditation of third-party electrical testing firms, certifying electrical testing technicians, as well as testing procedures and evaluation criteria.

These are not CE classes where you work your phone, have a coffee break and walk out with a certificate. NETA Certified Technicians have earned a Level II, III or IV NETA Certification in electrical power systems testing and bring the knowledge and field experience necessary to perform testing to industry standards. A NETA Technician's work experience, education, and training keeps them current with new technologies and provides them the knowledge to perform testing across a wide variety of power systems, insuring that the work is executed with the highest degree of safety.

So learning and building a knowledge base is really vital in this business.


Two ways to peel a shaft

In our last issue we talked about installing a shaft into a rotor with an interference fit. Removing a shaft from a rotor is basically the same thing in reverse, with a few changes. First thing is that the shaft cannot be completely encased in liquid nitrogen to reduce its diameter. And the rotor shaft combination, on these large units, will not fit into our bake oven, And based on these circumstances the similar job was accomplished in two different ways.

In this situation the rotor had been damaged so there was no need to worry about heat further damaging the windings, etc. The shaft was wrapped with insulation mats of polycrystalline mullite fibers, making it an extremely lightweight, highly resilient insulator and liquid nitrogren was pumped around the shaft, both top and bottom. Although the liquid nitrogen could not get right to the area in the rotor where the shaft makes contact, the cold did migrate from open ends to mid shaft points. After a little less than an hour it was time heat up the rotor enough to expand and free the shaft.

Four technicians with acetylene torches went medieval on the rotor starting on the outside and then shooting their torches down inside the rotor as well. Not only do the technicians have to pay attention to what they are heating, they need to be aware of what the other three are doing as well. Caution and safety with four torches in an eight foot diameter is vital.

What you have is a closing window where the rotor is heating up as well as the shaft. If it takes too long to heat the rotor, the shaft will warm, re-expand and not come out. The shaft/rotor unit is held up by our shop crane attached to the end of the shaft. This creates enough tension so that the instant the temperature differential reaches the right point the shaft will move up and then be quickly pulled out of the rotor.

When the shaft was removed from the rotor, the bottom of it was just 65 degrees while the rotor body was around 300+ degrees. Just simple physics.

Part One
This particular operation was different because we wanted to ensure that the rotor was not damaged during the heating process, since it was going to be reused. Instead of the more violent and extreme heat of the torches, induction heating coils were installed. This time the exterior of the rotor was wrapped with the fiber insulation and then strategically placed heating coils were placed around the exterior of the rotor. A complex wiring loom was set up from the power source to the coils. This would enable the amount of heat and the speed applied to the outside of the rotor to be more controlled.

As the final connections to heating elements were being wired the shaft was once again cooled down with liquid nitrogen. The shaft was wrapped with insulating mats, top and bottom, to retain as much cooling effect as possible, and again the shaft was given sufficient time to chill before the heating coils were powered up. The wire, in bundles and individual strands had a vague "Griswold Christmas" look to it.

Due to the extreme mass of the rotor the heating and expansion was done in two stages to protect the windings. The initial stage was heating the exterior to approximately 100 degrees C. Once there, torches were applied to the inner part of the rotor since it would be too long and slow for the heat from the coils alone to penetrate to the core of the rotor.

Technicians continuously monitored both shaft and rotor temperatures as the torches brought the hub up to the critical temperature. Even though that temperature window is there you can never be sure just what is going on down inside where the shaft and rotor are in contact.

A very satisfying "Thunk" and the shaft is free. It is quickly pulled up, out and away from the area to return to room temperature.

Part Two
This same rotor that gave up its shaft so nicely is going to receive another shaft before it cools down. Two torches more calmly bathe the core area with heat to maintain it's expanded state. While this is going on the new shaft has been in a full length cardboard tube with liquid nitrogen being pumped into the tube. Once the old shaft is out of the way the technicians quickly change over to installation mode. The new shaft is extracted from chilling tube and moved into position over the hot rotor.

Four technicians hover over the hot rotor while guiding the shaft into the opening. Cautious at first to be sure it is centered and then once the okay is given the shaft slides quickly and completely into the rotor. It will be 18-24 hours until the rotor/shaft combination cools down enough to be tested ensuring the rotor elements were ok. When it was finally tested all was good to go.


The Big Valve

The above valve came to us from one of our customers who handles a substantial amount of sewage and waste water. The valve itself is 8.5 feet in diameter and is designed to hold back a significant weight of water. The valve is secured in place with 52 bolts, each 2.25" in diameter. While the valve looked a lot worse for wear when it arrived (left) its main problem was silt/sand that had worked its way into the bottom of the opening over 40 years and ruined the sealing gasket. The design of the valve is not especially innovative, but its materials, manufacture and assembly were very well done.

Refurbishing began with a thorough cleaning and descaling. Once cleaned, a ceramic epoxy was applied to the working surfaces of the valve. These compounds come in various viscosities from putty-like to paint and have extremely tough corrosion resistant properties. Some have been developed for the marine industry where cavitation is severe and can literally destroy rudders.

Once that was completed the new gasket was installed, the mechanism and the motor that drives the valve were checked and found to be satisfactory.


Dallas Training Session 1995

Back in the 90's training was a whole different ball game. Paying $1000-$2000 for a course and flying to a two or three day seminar in Chicago or Dallas was standard procedure. Nice hotels, good contacts (networking was yet to come), socializing and picking up some valuable information.

Then things changed, namely the economy, and those types of training events pretty much disappeared for the average company.

I think everyone agrees that either refreshing the basics or learning the latest techniques is important for you and your company. However, training in our industry has become a bit of a nightmare for those conducting the courses and those trying to learn.

At Longo we ran local training seminars at our Wharton location on subjects from basic motor knowledge, pumps to VFDs and more. We would invite a broad range of attendees from mechanics to executives from our customers' companies. Maybe some of you attended. In house people and industry professionals provided hard info to use on the job, a free lunch and out the door by 2:30 PM. But, it became harder for many to take a whole day away from work so we upped the ante. The Battleship NJ became the classroom and we had a boost in attendance, but even that began to wane.

Today, webinars have become the norm. As a part of the work through lunch mentality, most cannot or choose not to leave their desk, much less their office or plant, so the seminars have to reach you where you are. As a result, today it is you, your monitor or tablet and a demonstrator streaming on your screen while you are having a sandwich.

At Longo we still feel the human interaction is important and now make ourselves available to our customers for Lunch & Learn talks. With 5, 6 or 12 company people and Longo representatives at your facility we cover a lot of ground in a variety of areas. Generalities turn into specific problems and their solutions. We get to know your situations and you get to know Longo and our level of competence. And...we bring lunch! To schedule a L&L e-mail info@elongo.com and put L&L in the subject line.


Hello...

Drones, or more accurately UAV(Unmanned Aerial Vehicles), are having an amazing transformation. From killing the enemy in the desert to seeing what your sunbathing neighbor is up to in less than a year is quite the trip.

Each time there is an announcement, such as Amazon delivering same day by drone, the real world is ten steps ahead. Checking pipe and power lines, solar and wind farms via UAVs is a great use, unless you are one of the crews that do the inspections now. From the cameras on the street corners to the explosion of private UAV's, the government will have to get in line for a crack at observing us!

The next big use of UAV's will be (or maybe already is) sports. Not watching them, but competing. "The World Cup of UAVs" both singles and teams. Singles would get points for the best videos in a 30 minute segment with judges awarding points like ice skating. The team version goes back to the drones roots with armament and size restrictions. Picture some space battle from a 60's movie but without any strings attached. The National Drone League or more likely some sort of NASCAR type organization, National Association of Drone Competition and Performance (NADCAP). Skeet shooting with UAVs will be a lot more challenging! The entire hunting industry will take a hit. No more cammo outfits or boots..or even rifles. Just sit on the cabin porch and send out the UAV to find that turkey or deer.

And video games vs. real UAV games? Probably the ultimate blend of fantasy and reality! While the actual business of UAV's is exploding the supporting industries will be quick to follow. Soon WalMart will be advertising UAV protection for windows that have a flowing digital screen that scrambles any video signal. Keeping with the insect theme...UAV Zappers. Like bug zappers these use lasers to zap or disable UAVs within 100 feet!

Literally the only limit on this industry is your imagination.



973-537-0400          One Harry Shupe Boulevard          Wharton, NJ 07885          elongo.com