| PTFE Clamp Valves - Details of Design
|
 |
|
 |
|
 |
| 1. The Clamp valve is a flexible
tube and a clamp. The tubing is made from TEFLONn® TFE.
|
|
2. A TEFLONn® TFE reinforcing
jacket heat shrunk over the tube element increases strength without sacrificing
flexibility.
|
|
3. The clamping mechanism consists
of a compressor which travels down a stem with rotation of the hand-wheel or power
operator, and a yoke which travels up the stem at the same time. Together these
components clamp off flow bubble-tight.
(Linear Actuated Clamp Valves utilize two similar compressors rather than one
compressor and a yoke.)
|
 |
|
 |
|
 |
| 4. TEFLON® inserts - teardrop
shaped in cross section - on each side of the TEFLON® tube prevent the tube
element from being overstressed. All flexing takes place on the center line of
the valve between the teardrops, insuring long life for the valve.
|
|
5. The radius clamps
are connected to the yoke and to the compressor by means of links and link pins.
These components, working together, provide a scissor-jack action which pushes
the tube element inward during the opening cycle and pulls it outward during closing.
|
 |
|
 |
| 7. Four lift forks inbedded top
and bottom in the tube element on each side of the clamp act as powerful fingers
which work with the links and link pins to pull the sealing surfaces apart even
under full vacuum conditions.
|
|
8. Operating parts are encased in
a ductile iron body with Standard ANSI Class 150 flanges. Because the valve is
symmetrical and completely bi-directional, either end can be placed upstream.
|
|
Four threaded safety vent holes
are provided, two in each of the symmetrical body halves, so that one hole is
always at a low point regardless of the plane of installation. Three of the four
holes are plugged when the valve is shipped. Plugs are easily moved to suit user's
preference for vent hole location.
|
