[Amps] Shipment of large old tubes

[Fuqua, Bill L]

  This does not happen by just laying on its side. It happens by dropping the item.
I have had a number of 4-1000A tubes that were shipped at the same time and by the same
company. These sat on the shelf for some years and when I opened them up the plates were 
badly off center. I suspect that they were tossed into the trucks even though they were
labled all the warnings on them. I managed to straighten them up by carefully bumping them
until they were centered again. After that they worked just fine. 
  The connection to the plate is different that that of a 250th but shipping companies just don't
care. 

73
bill wa4lav

________________________________________
From: amps-bounces at contesting.com [amps-bounces at contesting.com] On Behalf Of Colin Lamb [k7fm at teleport.com]
Sent: Friday, December 16, 2011 1:20 PM
To: amps at contesting.com
Subject: Re: [Amps] Shipment of large old tubes

A friend of mine called recently and told me he was cleaning out his basement and sending me some of his old tubes.  One was a 250TH.  I got it last night.  It was packed very well, along with other tubes.  The box arrived with no damage.

However, when I unpacked the 250TH, I noted that the metal stem above the plate had fatigued, causing the plate to be loose inside the still good glass.  I believe the damage was fatigue because the tube was laying on its side, rather than being shipped vertical.  I recall a few years ago, I shipped some old tennis ball Western Electric 205D tubes on their side.  The top internal structure is supported by a vertical glass rod.  They were shipped on their side and all had broken glass rods, even though the tube envelope was still good.

I expect modern tubes do not suffer this fate, and there is always the problem that what is shipped vertical is not likely to remain vertical during shipment.

So, this is just a word of caution.

73,  Colin  K7FM
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