Thursday, July 17, 2008

Tube System Tales - Epilogue

Sunday night, one of the four APU's (blower) motor bearings went to pieces. The decision was made to tear the motor down to see how much damage had been done. My 'mentor' joined me, and helped me disconnect it and unbolt it from the floor.


The APU lineup.
The black boxes are air shifters. Air goes into the motor on the left tube, out of the motor on the right, the air shifter's like a paddle that moves in a circular housing to direct the flow.


Here's the APU off the floor.
Notice the screens at the bottom. The inlet side is about 70% PLUGGED. The outlet side, about 40% PLUGGED.

My 'mentor" - the guy that I'd inherited the system from, was flabbergasted. He had no idea that these screens were there, let alone that they needed to be cleaned. The preventive maintenance work order procedure (quarterly) says to clean the blower motor screens, but he thought that meant another set of screens that are on the air shifters. Upon further discussion, and questioning, there were other employees that knew of this need, and had in fact performed this maintenance - it was a situation where the proper information had not been passed along from knowledgeable people to those that needed to know. These screens had not been inspected or cleaned for at least THREE YEARS.

I left the motor tear down to the real mechanics, and returned to the tube room. One at a time, I cleared and cleaned blocked screens. Four hours later, I had a rockin' tube system. To express it numerically, tube stations where my meter had shown vacuum of 5 inches of water now showed 15. The BOC guy got a complaint call from one floor secretary that her tube station was making too much noise - no, baby, that's the sucking sound of success!

That nagging feeling that something wasn't the way it was supposed to be was gone. The need to primp and preen each opening and orifice to keep minimum functionality was gone. The pressure, now on full blast, was off me. I was observed, smiling, at work - a phenomenon rarely seen since the turn of the century. Like the motors, I was relieved. It is now 10 degrees cooler in the tube room than it usually is. Transactions - tracked by the computer - are taking 2/3 of the time they used to take to get there. Faster. Better. More reliable. Me happy.
I can deal with this.