VACUUM PUMPS ION PUMPING

Transcription

1 ION PUMPING Meca 2000 ion pumps are Diode type. They can reach pressures down to mbar thanks to their UHV design. They require no maintenance and are easily started from 10-4 mbar. They are often used in installations permanently kept under vacuum. Two types of ion pumps are proposed: the ionic pumps of the PID series and of the PIDG series. The PIDG ones are ion pumps with integrated titanium sublimation. For both series, the integrated pumping elements differ depending on the type of gas pumped. For the noble gases which do not combine with titanium, we install special pumping elements for noble gases. ION PUMPS PID SERIES : The ion pumps of the PID series have an operating voltage of 5 kv supplied by dedicated power supplies. The current absorbed by these pumps is proportional to the pressure (see graph on opposite page), its value is given by the power supply. The shape of the ceramic insulators of the pumping elements and the high voltage connector minimize the risk of electrical leaking current. The excellent symmetry of the magnetic circuit also gives a very low stray magnetic field. It consists of standard ferrite elements (magnets) with a very large magnetic field. The maximum bakeout temperature of these pumps is 200 C with the magnetic field and 300 C without magnetic field. Those pumps can have standard elements or noble gas elements. - Standard elements: PID series pumps are composed of standard 25 L/s elements (12.5 L/s for PID 50) easily interchangeable and experience has shown they were the most reliable and robust. The standard pumping element consists of a cathode made by 2 getter materials (titanium) plates and one anode consisting of multiple stainless steel cylinders (see schematic diagram on the opposite page). - Noble gas elements: Noble gases do not combine with Titanium and can only be buried. Pumping speed on those gases is reduced. If a high quantity of noble gases is to be pumped the pumps must be fitted with noble gas elements which combine several materials. The pumping speed of noble gases is then considerably increased. ION PUMPS PIDG SERIES: The PIDG series combines a diode ion pump PID with a titanium sublimation pumping. Operating principle: o Ion pumping With the same design as the PID pumps, PIDG pumps supply the basic pumping of a system and do not require any maintenance. o Titanium sublimation pumping The titanium sublimation highly increases the pumping capacity. The pumping speed given by the sublimation is proportional to the deposition surface and its temperature. Thus internal pumping speed higher than 2000 L/s can be obtained. The lower the temperature of the cooling panel is, the higher the pumping speed will be. For a better pumping of the hydrogen, liquid nitrogen cooling is needed in order to improve condensation. 74 VINCI TECHNOLOGIES Division MECA

2 Current - Pressure curves Pumping mechanism PUMPING SPEED: The pumping speeds are purely indicative as they depend on the conditioning of the pump and the gas mixture pumped. The values given below refer to measurements made according to ISO standards. The maximum flow rate (number of molecules pumped per second) is typically around mbar. N2 pumping speed Pumping speed on dry air is slightly higher than on nitrogen. However it is advised not to operate the pumps permanently under air pressure higher than mbar as Argon could bring some unstability. If this kind of application is considered, then pump should be fitted with noble gas elements. VINCI TECHNOLOGIES Division MECA

3 ION PUMP PID PID 25 PID 25N PID 50 PID 50N Nominal pumping speed 25 L/s Nominal pumping speed 50 L/s Number of elements 1 Number of elements 4 Power supply APIV ref: Power supply APIV - ref: Bakeout Heating rod Bakeout EP50 Inlet flange 40CF Inlet flange 100CF Mass 12 Kg Mass 30 Kg Reference standard model Reference standard model Reference noble gas model Reference noble gas model PID 100 PID 100N PID 200 PID 200N Nominal pumping speed 100 L/s Nominal pumping speed 200 L/s Number of elements 4 Number of elements 8 Power supply APIV ref: Power supply APIV - ref: Bakeout Heating rod Bakeout EP200 Inlet flange 160CF Inlet flange 160CF Mass 58 Kg Mass 65 Kg Reference standard model Reference standard model Reference noble gas model Reference noble gas model VINCI TECHNOLOGIES Division MECA

4 PID 400 PID 400N PID 600 PID 600N Nominal pumping speed 400 L/s Nominal pumping speed 600 L/s Number of elements 16 Number of elements 24 Power supply APIV - ref: Power supply APIV - ref: Bakeout EP400 Bakeout EP600 Inlet flange 160CF Inlet flange 160CF Mass 150 Kg Mass 165 Kg Reference standard model Reference standard model Reference noble gas model Reference noble gas model PID 800 PID 800N Nominal pumping speed 800 L/s Number of elements 32 Power supply APIVD - ref: Bakeout Inlet flange Mass EP CF 251 Kg Reference standard model Reference noble gas model VINCI TECHNOLOGIES Division MECA

5 PIDG COMBINED ION PUMPS PIDG 1020 PIDG 1020N PIDG 1040 PIDG 1040N Nominal pumping speed 1000 L/s Nominal pumping speed 1500 L/s Number of elements 8 Number of elements 8 Power supply APIV / ASTI 7 Power supply APIV / ASTI 7 Bakeout EP200 Bakeout EP400 Inlet flange 160CF Inlet flange 160CF Mass 85 Kg Mass 170 Kg Reference standard model Reference standard model Reference noble gas model Reference noble gas model VINCI TECHNOLOGIES Division MECA

6 PIDG 1060 PIDG 1060N PIDG 1080 PIDG 1080N Nominal pumping speed 1600 L/s Nominal pumping speed 1800 L/s Number of elements 24 Number of elements 32 Power supply APIV / ASTI 7 Power supply APIV / ASTI 7 Bakeout EP600 Bakeout EP800 Inlet flange 200CF Inlet flange 200CF Mass 230 Kg Mass 260 Kg Reference standard model Reference standard model Reference noble gas model Reference noble gas model ION PUMPS SPARE PARTS SPARE PARTS Model Description Reference EPI 12 Standard 12,5 L/s element EPI 12 N Noble gas 12,5 L/s element EPI 25 Standard 25 L/s element EPI 25N Noble gas 25 L/s element PMHT HV feedthrough 16CF PBHT HV connector VINCI TECHNOLOGIES Division MECA

7 CORDONS D ETUVAGE HEATING TAPES Model Model Model RC RC RC RCL RCL RCL RCT 2 RCT 2 RCT 2 RCT 4 RCT 4 RCT 4 BAKEOUT LAMPS ModEl A Specifications Reference LIEC V, 500 W LIEC V, 1200 W LI Spare halogen lamp, puissance 500 W LI Spare infrared lamp, puissance 1200 W VINCI TECHNOLOGIES Division MECA

8 ION PUMPS BAKEOUT ACCESSORIES Bakeout accessories ensure the maintenance and regeneration of ion pumps in order to maintain their initial performance. A periodic baking at around 150 C eliminates the wat er vapor and secures an excellent ultimate vacuum. Bakeout accessories for ion pumps are of two types: - Heater rods BC models: for pumps 25 L/s and 100 L/s They are placed in corresponding tubes, 1 for 25 L/s pumps, 4 for 100 L/s pumps - Bakeout ovens EP models for ion pumps 50 L/s to 800 L/s They are placed around the pumps and they ensure of uniform temperature of the pump between 150 C and 200 C. BATON CHAUFFANT : Modèle BC ETUVE POUR PID 50 : Modèle EP50 Caractéristiques électriques : 220 V, 75 W Caractéristiques électriques : 220 V, 300 W Référence : Référence : ETUVE POUR POMPES IONIQUES PID 200 à PID 600 Modèle EP 200 EP 400 EP 600 A B C D E F Caract. électrique 220 V, 400 W 220 V, 600 W 220 V, 800 W Référence VINCI TECHNOLOGIES Division MECA

9 TITANIUM FILAMENT HOLDERS Model Reference PFT PFT PFT SPARE PARTS Model Model Model FTIS 30 FTIS 30 FTIS 30 FTI 12 FTI 12 FTI 12 FTI 50 FTI 50 FTI VINCI TECHNOLOGIES Division MECA

10 ION PUMPS POWER SUPPLIES The high voltage power supply (3 kv to 7 kv) for ion pumps is a modular unit designed the extensive needs of users of ion pumps. The APIVD model has been specially developed to offer the user the possibility to operate two pumps simultaneously or independently with an individual reading of the current and pressure. It also has independent setpoints. These power supplies are programmed to automatically convert the reading of the ion pump current into pressure measurement (range mbar). The base unit comes in the form of a box 1/2 rack in which a high voltage card is installed for the diodes ion pump 25 L/s to 800 L/s. SPECIFICATIONS: - Input voltage: 220 V / 50 Hz - Dimensions: ½ standard rack 19 inches (H : 177, L : 211.4, P : 440) - Front panel readings: Output voltage Pressure Current - Output voltage: adjustable between 3000V and 7000V Model Description Reference APIV High voltage control unit APIVD High voltage control unit for 2 ion pumps CPHTF High voltage cable from controller to pump TITANIUM SUBLIMATION POWER SUPPLY The titanium sublimation power supply gives the necessary heating current for filaments used with the MECA 2000 titanium filament holder. A controller installed on the front panel adjusts the interval between two cycles and the time of sublimation. A 5 position switch allows the selection of the operating filament or the automatic control. SPECIFICATIONS: - Input voltage: 220 V / 50 Hz - Sublimation time: 1 or 2 minutes - Sublimation intervals: 1 minute to 99 hours - Current: automatic regulation - Dimensions: 19 inches (H: 88, L: 482.4, P: 370) Model Description Reference ASTI 7 Universal power supply for titanium sublimation CABLE HI HV cable 6 meters VINCI TECHNOLOGIES Division MECA