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Bell Jar Sizes and Specifications

Glass Vacuum Bell Jars

Glass bell jars are available from HyVac in a number of sizes and configurations.  All bell jars are rated for full vacuum.  They are made of the highest quality materials to assure full performance.  Glass bell jar options are not that extensive and come in two flavors.  Options include knobs on top or a plain top.  Choice two is a flange on the bottom where it mates to the bell jar plate/base or a plain bottom.   Wall thickness of jars varies between .23-.31".   A flange on the bottom adds between .25-.50" to overall diameter.

Knob              Flange

Sizes Available
inches Diameters 
  Sizes Available
inches Height
B B   A
18" 7"   30"
15.375" 6.5"   24"
12.5" 6.0"   18"
10.25" 5.5"   12"
9.5" 4.25"   8"
8.25" 3.25"   6"
Flanges add 1/4" OD to B Dimension

Glass Bell Jar Technical Information

Composition  - Type 1, Class A, low expansion borosilicate glass conforming to Federal specification DD-G-54 lb and ASTM E-438.  These jars also meet US Pharmacopoeia (USP) specifications for Type 1 borosilicate glass.

Composition of borosilicate 
glass in HyVac bell jars:
Material  % approximate
SiO2         80.6
B2O3        13.0
Na2O         4.0
Al2O3      2.3


Physical Properties Value
Coefficient of Expansion 32.5 x 10-7 cm/cm/C
Strain Point               510 C
Anneal Point          560 C
Soften Point                  821 C
Density      2.53 grams / cm3
Youngs Mod. 76.0 x 101 Kg / mm2
Refractive Index      1.474 @ Sodium D Line
Temperture Limits  490 C Extreme Service
230 C Normal Service
Maximum Thermal Shock 160 C
And yes.... we have gaskets and straps and bell jar cages.

Gaskets are ordered per diameter of jar and whether there is a flange or not on the jar.  useful in protecting the bottom of the jar from nicks and dings.

Bell Jar Cages are a safety purchase to place a wire mesh screen between the user and a pressurized glass bell jar.  They again depend on the diameter of the jar they are about 1.5" larger than the jar they fit.  And height of course to accommodate the height of the jar.  

Straps are used about mid way between the top and bottom of the jar primarily to insulate the jar from inserting the cage over the jar.   Protects the jar from damage when putting the cage on or taking it off.

11/26/2005 ęCopyright HyVac Products, Inc. All Rights Reserved
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