• Sealing capability in dead spaces near the floor
  
• Self-adjusting capability for high temperatures
  
• Integrated PT100

Borosilicate glass 3.3 is a preferred material in the chemical and pharmaceutical industry due to its smooth and inert surface. Its excellent suitability for GMP applications must be supported by employing engineering designs that fit specified requirements, e.g. safety flat buttress ends with GMP seals, or dead space free bottom outlet valves, as here mentioned. They are available for the following vessel types:

• Graduated receiving flasks
• Double-wall jacketed reaction vessel
• Triple-wall jacketed vessels
• Glass vessels type OptiMix®

The vessels are equipped with a pre-fabricated nozzle, melted into thevessel walls, whereby the discharge port shall be drilled and honed for high-precision requirements. Due to this, sealing capability is possible with nearly no dead space.

Design of the Valve
As PTFE is loosing strength at high temperatures, high-grade connections are equipped with spring elements at QVF. The new bottom outlet valve implements two sealing design capabilities in this respect. The first sealing design capability is performed in a self-adjustable fashion, and almost without a gap at the position 1 (illustration 1) between glass body and valve bellow. The spring at position 2 (illustration 2) is pre-loaded due to the closing movement of the valve, thus enabling resilience against PTFE flow upon warming and delivering sealing capability at the same time.
The fold wrinkles of the bellow that experience product attack are designed in a rounded fashion in order to enable for drainage during open operational status, and to enable well-cleansing capability.
Three different valve lengths are available for different vessel types.

<<<< Design structure of the bottom outlet valves

Technical Data
Active sensor tip: 30 mm protruding into the product
Sensor type: 4 cable-design PT100
ATEX license: PTB 00 ATEX 2075 U
Ex protection grade: II 2G EEx eII
Installation mode: Using heat inductive paste
Response time: About 3 minutes
Temperature deviation: about 3°C
Connecting cable: About 2.7 meters

<<<< Bottom outlet valves employing PT100

In many cases, temperature measurement is favorable by employing the bottom outlet valves, e.g.:

• Small residual amounts of fluid
• OptiMix® without a baffle installed in the cover

The advantages of the dead space free design remains fully sustained for the QVF bottom outlet valves employing PT100. The PT100 is assembled at the machined top, without the need of an additional sealing. The thermometer displays fast response, and measures the product temperature in an area outside of the jacket due to the positioning in the vessel, thus enabling itself not to be effected by the service side. The temperature deviation, which results from the PTFE jacket, amounts to about 3°C and may be taken into account during calibration of the thermometer.

Torque Limitation
Upon demand, the valve may be equipped with a torque limitation, as the integrated spring adjustment of the valve may be over-wound by forced turning. This is a standard feature for triple-wall vessels.

<<<< Bottom outlet valves employing security device against over-winding

• S - graduated receiving flasks

• M - jacketed vessels

• L - triple-wall vessels