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Replacement Ion (Hot Filament) Gauge Tubes

Bayard-Alpert (B-A) ion gauges have a reasonably linear response from 1 x 10-4 to 1 x 10-9 Torr (1 X 10 -4 torr to 5 X 10-12 torr for nude UHV gauges) with gauge sensitivities from 5 to 20 Torr-1. B-A ion gauges are available with one or two filaments, where the second filament would act as a spare). The filaments are available in two materials. The first material, a thoria-coated iridium, is used in oxygen-rich applications and is resistant to "burn-out" if exposed to atmosphere. This material is not intended for applications that will expose the filament to chemicals. The second material, tungsten, is a lower cost material that is resistant to chemical exposure, including halogen-based chemicals, but will "burn-out" if exposed to atmosphere.

Dimensional Drawings

Pinouts

Legend:

G = Grid
F1, F2 = Filament
FC = Filament Common
C = Ion Collector


Filaments Comparison:

  Iridium (ThO-Ir) Tungsten (W)
Exposure More forgiving to exposure to higher pressures Susceptible to failure if exposed to higher pressures
Outgassing Less outgassing, optimum UHV choice More outgassing, optimum for HV
Reactivity Reactive with hydrocarbon and halogen gases More stable with hydrocarbon and halogen gases
Cost More expensive Cost Effective

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Contact Us
To speak with someone directly, please call +1 412 387 9200 or email international@lesker.com.
Note:
Platinum (PT) Coated Filaments are used to ground spurious electrons generated by thermionic emission of the filament so that the glass does not develop a potential. This is recommended when the experiment involves detecting signals of a very small voltage.

Accessories Table

Accessory
Type
Description Part Number Price In Stock Add
Item
Accessory
Type
Description Part Number Price In Stock Add
Item
OFHC Copper Gasket
Compatible with 2.75" CF Tube Termination
GA-0275
$27.35
In Stock
Bolt Set
Compatible with 2.75" CF Tube Termination
HBS25028138
$30.50
In Stock
Viton O-ring with centering ring
Compatible with KF25 Tube Termination
QF25-100-SRV
$8.55
In Stock
Clamp
Compatible with KF25 Tube Termination
QF25-100-C
P.O.R.
In Stock
Viton O-ring with centering ring
Compatible with KF40 Tube Termination
QF40-150-SRV
$13.10
In Stock
Clamp
Compatible with KF40 Tube Termination
QF40-150-C
P.O.R.
In Stock