Bellows Sealed Valves for Ultra High Vacuum System
Introduction
Vacuum valves are indispensable components of any vacuum system extensively used in research and development work and in many process lines. These facilitate isolation of a part of the system during servicing, maintenance, loading of samples etc.
Both angle and in-line valves are bellows sealed to ensure high leak tightness during their operation. In-line type includes gate and butterfly valves and angle type a right angle valve. Gate type is available in 6 mm and 12 mm sizes, which are `High Vacuum' compatible and 25 mm size, which is `Ultra High Vacuum' compatible. Butterfly type has the largest open conductance and is highly compact in size. It can also be used as a throttle or conductance control valve. Gate valves being fully open and in-line valves offer unrestricted opening and are ideally suited for applications such as beam transportation systems and load locks for sample introduction. Right angle valves are used for roughing and baking, venting and leak testing applications.
The vacuum valve is made of three members namely
- Valve body
- Sealing plate and
- Trim or actuating mechanism.
Valve body
Construction of material is SS-304. It has a flange on top for mounting the actuacting mechanism. The end configuration conforms to ISO standard such as Klein flange or Conflat.
Sealing plate
This is a disc/ flapper plate/ wedge shaped piece
Actuating mechanism
Screw type All parts prior to assembly need to be thoroughly cleaned & dried.
Raw materials
| All main parts | SS 304 |
| Bellows | SS-316 L or 321 |
| Plate / Body Seal | Soft Viton `O' ring |
- Leak tight valves operating in the range of 10-6 to 10-9 torr
- Right Angle and In-line types
- High Reliability
- Manual /Automatic Operation
- Long Service Life
- Easy Serviceability
- Ability to withstand repeated bakeouts
Specifications
| Size | 6 mm | 12 mm | 25 mm | 63 mm | 100 mm |
| Type | Gate | Gate | Gate/ Rt. angle | Butterfly | Gate/ Butterfly |
| Mounting Flange | KF | KF | CF/KF | CF | CF |
| Operation | Manual | Manual/ automatic | Toggle/ automatic | Manual/ automatic | Manual/ automatic |
| Bakebility (open condition) |
150 0 C | 150 0 C | 300 0 C/ 150 0 C | 300 0 C | 300 0 C |
| Overall Leak Tightness | 1x10 -9 cc/sec | 1x10 -10 cc/sec |
1x10 -11 cc/sec | 1x10 -11 cc/sec | 1x10 -11 cc/sec |
For further information please contact
Head,
Technology Transfer & Collaboration Division,
Bhabha Atomic Research Centre,
Trombay, Mumbai - 400 085
Tel : 091-022-25505337/25593897
Fax : 091-022-25505151
E-mail : headttcd@barc.gov.in
