The system consists of two separated parts:
- A benchtop horizontal split tube furnace for temperature control of the liquid sample. It has a removable tube-shaped temperature chamber with inner diameter 100 mm, and provides a temperature stability better than ±0.5°C.
- A floor-standing liquid pressure control unit for pressure control of the liquid sample. It uses a servo motor with pump screw, enabling a precision in pressure of around ±1.0 Bar.
The liquid cell containing the liquid sample has a cylindrical shaped volume of 1.1 ml. It is made for use with our Kapton-insulated Hot Disk® sensor models 7577Q and 5465Q, which have a double-spiral diameter of 4.0 and 6.4 mm, respectively, and extended cladding. To position the double-spiral of the horizontally mounted Hot Disk® sensor in the center of the cell, the body of the liquid cell, which is made of stainless steel, is dividable via releasing four bolt screws on its top. Once the sensor is in position, the cell is sealed by tightening the four bolts and utilizing reinforced graphite gaskets. The liquid sample is transferred to the cell via tubing on the side of the body. There are two tubes accessing the liquid cell: one for liquid inlet, and one for liquid outlet. The liquid cell and tubing are carefully flushed with Argon gas before filling with the sample liquid.
The liquid cell and a sensor fixture are located on the front end of a specially designed insert for the tube-shaped temperature chamber. The insert is slided into the tube chamber opening with help of an integrated slide bar. The tube chamber is thereafter sealed by tightening the eight bolt screws on the back side of the insert. The tube chamber and insert are made of stainless steel, and close to the tube chamber opening the tube has an integrated liquid cooling coil pipe. This is used to protect the gasket in the bolt connection between the insert and tube as well as the sensor cable feedthrough, ferrules for liquid sample inlet/outlet, and outside wiring and tubing, of the insert. For this cooling we recommend the use of a chiller (cooling water circulator) that we supply on request. The tubing on the outside of the insert (with connecting ferrule, gas inlet/outlet, venting/drainage valves, safety valve, expansion volume) accommodates for the manual switching between Argon flushing and liquid sample supply, as well as incorporating safety measures for an unexpected over-pressurized liquid.
The liquid sample is supplied to a cylinder reservoir in the liquid pressure control unit. A piston inside, controlled by a servo motor and pump screw, is used to pump the sample liquid to the liquid cell (inside the tube furnace) and to set its pressure. The pressure can be monitored by both an analogue and a digital manometer on the liquid pressure control unit, enabling visual inspection and remote control, respectively. The initial pump procedure is done manually using the control panel of the liquid pressure control unit. The following pressure setting is either done manually with the control panel or automatically via remote control.
Both the temperature and pressure setting of this pressurized liquid cell can be controlled via the Hot Disk® Desktop App, where RS232 communication is used for the tube furnace and USB communication is used for the pressure control unit. The software can be programmed to automatically perform a series of measurements with the Hot Disk instrument at multiple liquid temperatures and pressures.
| Temperature range | Up to 400°C |
|---|---|
| Pressure range | Up to 250 Bar |
| Sensor model | Kapton-insulated Hot Disk® sensor model 7577Q and 5465Q |
| Cell | |
| Volume | 1.1 ml (40 ml including all tubing) |
| Diameter | 15 mm |
| Thickness | 5 mm |
| Material | Stainless steel, graphite |
| Temperature chamber | |
|---|---|
| Diameter | 100 mm |
| Length | 740 mm |
| Heated length (hot zone) | 360 mm |
| Cooling system | Water circulation |
| Heating system | Multiple zone heating elements |
| Temperature range | Up to 400°C |
| Temperature stability | <±0.5°C |
| Supply voltage | 200-240 VAC, 50-60 Hz, 1 Phase |
| Power rating | 9.5 A/1600 W |
| Input/Output | RS232 (female) |
| Dimensions (height x width x depth) | |
| Furnace (without tube) | 500 mm x 635 mm x 620 mm |
| Control unit | 380 mm x 340 mm x 230 mm |
| Tube with insert | 410 mm x 940 mm x 240 mm |
| Weight | |
| Furnace (without tube) | 87 kg |
| Control unit | 11 kg |
| Tube with insert | 22 kg |
| CE marking | Yes |
| Cylinder reservoir with pump piston | |
|---|---|
| Liquid volume | 245 ml |
| Piston stroke | 120 mm |
| Pressure control | Servo motor with pump screw |
| Pressure range | Up to 250 Bar |
| Pressure stability | ±1.0 Bar |
| Supply voltage | 200-240 VAC, 50-60 Hz, 1 Phase |
| Power rating | 1.0 A/200 W |
| Input/output | USB Mini (female) |
| Dimensions (height x width x depth) | 750 mm x 610 mm x 360mm (including floor stand and control unit) |
| Weight | 22 kg (including floor stand and control unit) |
| CE marking | In progress |
