World's Largest Round Vault Door

[wylk]

I do not see a bolt-throwing hand-wheel on these doors only a pressure system hand-wheel, nor are there any combination dials or jamb controls... The only jamb control I see is on the Cleveland Trust door in the form of a hand-wheel that I believe operates the entrance platform. There is an interesting electrical panel above it.

Cleveland Trust doors were "automatic" so the bolts were thrown closed by the bolt motor (big springs) when the door was closed, and the time lock would trigger the bolt motor to withdraw the bolts at the appropriate time. Thus there were no holes through the door (or the door frame as with Holmes designs) and no combination locks and no bolt-throwing handwheel. A disadvantage is that in case of riots the door will still unlock itself, allowing access by the marauding mobs.

[wylk]

Also, there is some sort of 'escape hatch/chamber' at the rear of the Cleveland Trust vault that leads to the emergency door. This does not appear to be a common vault feature.

Emergency doors often mimicked basic design features of the main door (same locks, same time locks, same thickness) though some liberties were taken due to the smaller size. In this case I notice that the main door is actually a double door (single round door on the outside, double rectangular doors on the inside). I've seen this called a "vestibule" door at times. So it's no real surprise to see a double design used for the emergency door (here the interior door looks like a round bayonet style rather than a double rectangular door).

[Chubby]

Cleveland Trust doors were "automatic" so the bolts were thrown closed by the bolt motor (big springs) when the door was closed, and the time lock would trigger the bolt motor to withdraw the bolts at the appropriate time. Thus there were no holes through the door (or the door frame as with Holmes designs) and no combination locks and no bolt-throwing handwheel. A disadvantage is that in case of riots the door will still unlock itself, allowing access by the marauding mobs.

That is why anti insurgency locks are a must!

[Huw Eastwood]

The crane hinge on the Cleveland Trust vault is connected via 'hinge pin' extending from top to bottom. This design appears to be common on doors with 'X' pattern pressure systems

Cleveland Trust
Attachment 13154

Others
Attachment 13155 Attachment 13156

The second door you posted is also unusual having a hexagonal housing for the pressure bar drive

[VaultDoors]

The second door you posted is also unusual having a hexagonal housing for the pressure bar drive

The only other hexagonal pressure housing I know of is at the old Union Trust branch at 337 Fourth Avenue, now home to the Engineer's Society of Western Pennsylvania (info from wylk). Here is a picture (from Doug McQueen) that was posted in the 'Hollar Round Door Vaults' thread years ago.

[Huw Eastwood]

Nice contrast- the hexagonal housing in brass stands out with the handle against the door. Nice brass finials on the hinges and matching door pull as well. Shame the door surface looks like they let a clown loose to clean it with a rotary brush on an angle grinder..

[VaultDoors]

Does anyone know the approximate PSI a pressure system must exert on a door to ensure a tight fit? I assume less pressure points require more pressure per point to achieve the same pressure.

1 horizontal bar = 2 pressure points: — pattern
3 bars (12:00/4:00/8:00) = 3 pressure points: Y pattern
2 parallel,horizontal bars = 4 pressure points: = pattern
2 crossed bars = 4 pressure points: X pattern

[Huw Eastwood]

An interesting subject which rarely surfaces and reveals little information.

Most of the facts and figures seem ignored by manufacturers in their usual 'open specs', perhaps because they saw them as less meaningful and having less punch, compared to more obvious statistics like door thickness, weight, grades of steels etc?

There are some facts and figures out there, but bear in mind most of the big old doors with the hefty pressure systems were booming in the 1920s and 30s- at a time when some 'interesting' claims were specified, along with the obligatory use of the shortest bloke within 20 miles of the factory for publicity photographs etc- all part of the competition between them back then. The concepts, calculations and engineering behind it all was undoubtedly seriously clever stuff, but even then, mathematics on paper, physics in theory and the full size 3-D product in the real world don't always match up- like some of the other facts and figures I'd take them with a pinch of salt.

I know Chubb have revealed some figures for their old treasury doors in the past, and I posted some pressure details in my thread on the big Italian Parma doors a year or so back. Parma apparently attained incredibly high pressure from their system which was many thousands of kilos from memory, which I think was suggested to be much higher than most at the time, but who knows, you can probably make of it what you want.

It'd be interesting to see if anyone with old literature has anything with references to pressure systems and the figures involved.

[Chubby]

Interesting topic. I also wonder how much pressure was exerted by those clamping devices there used to be on the Chubb 3.5" (and bigger) TDR doors. They were just an acme threaded screw worked by a hand wheel but they certainly clamped those doors watertight. I only ever saw them on SR doors, though, never on a safe.

[Doug MacQueen]

Somewhere I read the pressure systems are typically capable of generating about 1/3 the door weight. Combining this with the ramping effect of the door/ jamb taper helps to ensure closure on a less than perfect fit, even overcoming some drop and tip wear. Opening the door is a greater challenge than closing since you don't have momentum to help. On the Cleve Fed door the simple crossbar acts at the most efficient point to pull the door straight out of its pocket, keeping it from cocking sideways.