CHEMICAL PETROCHEMICAL REFRIGERATION ENGERGY SERVICE. Convincing worldwide: HERMETIC pumps in the refrigeration industry

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CHEMICAL PETROCHEMICAL REFRIGERATION ENGERGY SERVICE Convincing worldwide: HERMETIC pumps in the refrigeration industry

RESPONSIBILITY FOR THE ENVIRONMENT Attitudes towards environmental awareness as well as social responsibility have steadily grown in the refrigeration industry. As an essential feature refrigeration plants must operate in a hermetically sealed way and thus, the importance of tightness has become more and more important for engineering, ecological and economical reasons. Therefore, both safety in plants as well as environmental protection play an important role in business strategy. Not only ice-cream and frozen foods need to be cooled, but almost every food. Typical application ranges include rail vehicles, toboggan-runs, bob runs, breweries, etc. in which HERMETIC pumps have been successfully used for reliable cooling of plants and production processes. HERMETIC has been dedicated to the development and production of hermetically sealed pumps for a period of years. HERMETIC pumps are designed for applications in the chemical and petrochemical industry, as well as for process technologies. The refrigeration industry also benefits from this experience made in these industries. There are more than 7. HERMETIC pumps installed in refrigeration plants worldwide. Hermetic

HERMETIC synonym for hermetically sealed pumps and reliability Qmin-Orifice Compressor Evaporator Separator Cooling water Condenser Flow control valve HERMETIC pump Qmax-Orifice or constant flow regulator The figure shows the simplified scheme of a large refrigeration plant. The characteristic of this plant is that the refrigerant flows through a central fluid separator and is then conveyed to the evaporators. The resulting vapour and the surplus fluid return back to the separator. Compressor, condenser and flow control are incorporated in a secondary circuit. Hermetically sealed pumps ensure a safe and controlled conveying of refrigerants. Besides absolute tightness HERMETIC refrigeration pumps feature the following: long service life low operating costs rapid and reduced acquisition and stockkeeping of spare parts. Hermetic

S ingle - S tage C anne d M otor P u mps General HERMETIC pumps are completely selfcontained centrifugal pumps without any shaft sealing, driven electromagnetically by the canned motor. The CNF model has been specially developed for pumping liquefied petroleum gas. This single-stage pump design now allows for the pumping of liquefied petroleum gases with an extremely steep vapour pressure diagram. There is no need for external re-circulation of the partial flow into the suction vessel and the separator. Design The pumps use a single-stage impeller mounted directly on an integral induction motor. The pump volute casings and impellers are derived from the standard chemical pumps as defined by EN 88; ISO 88. Hermetic Operating range Capacity Q: max. m/h Head H: max. 7 m.c.l. Application sector Liquid gases as e.g. R 77 (NH), R (Frigen), CO, R a, R a, R, R, baysilone (M, M), methanol, silicon oil KT, syltherm, lithium bromide. In principle the refrigeration pumps are suitable for use with all refrigerant liquids. Please consult for any fluids not listed above.

P u mp Bearings Slide bearings radially guide the common pump and rotor shaft. This guiding is used during the starting phase and the stopping phase since the guiding function is hydrodynamically taken over by the rotor after the nominal speed of the canned motor has been reached. The axial thrust of our pumps is hydraulically balanced. Safety Devices and Monitoring We recommend to protect HERMETIC pumps against any extreme flow conditions by means of two orifices. Orifice (Qmin) ensures the minimum flow rate required for the dissipation of the motor heat loss. Orifice (Qmax) ensures the minimum differential pressure in the rotor chamber needed for stabilising the hydraulic axial thrust balance and for avoiding the evaporation of the partial flow. Moreover, this orifice prevents an interruption of the flow of discharge if only a certain minimum suction head is available. Alternatively to orifice (Qmax) a constant flow regulator can be installed (see page -). C N F Return of partial flow to discharge side Pressure-Temperature-Diagram ➊ ➍ Δp Operation The partial flow for cooling the motor and lubricating the slide bearings is separated through a ring filter and, after having passed through the motor, is carried back again to the delivery side of the pump. An auxiliary impeller serves to overcome the hydraulic losses encountered along the way. The return of the partial flow to the delivery side ensures that point in the Pressure-Temperature-Diagram (Figure ) is sufficiently distanced from the boiling-point curve of the diagram. With the CNF model, it is thus possible to pump liquefied petroleum gases with an extremely steep vapour pressure diagram conditions being the same, except for the gas to be pumped. S eries ➌ ➋ Δt ➊ ➋ ➌ ➍ Pressure Temperature Vapour pressure curve Boiling-point curve Figure Hermetic

Performance Curve CNF - Performance Curve CNF - Q [m/h] Q [m/h] Ø 9 Ø 9 η% η% Performance Curve 8 rpm H [m] 7 Performance Curve 8 rpm Q max-orifice Ø Ø Ø Q max-orifice Ø Ø 8 Ø Ø H [m] Q max-orifice Ø Q min-orifice Ø Q min-orifice Ø PSH-value are measured quantity; N safety margin of, m is required NPSH [m] Ø Q max-orifice Ø 8 Inducer P [kw] Ø Inducer Ø Ø 8 Ø Impeller 9 - mm Ø, Width 9 mm Impeller 9- mm Ø, Width 7 mm Performance Curve CNF - Performance Curve CNF - Q [m/h] Q [m/h] 7 8 9 7 8 9 Ø 9 Performance Curve 8 rpm Ø Performance Curve 8 rpm Ø 9 η% H [m] Q max-orifice Ø Q max-orifice Ø 7 Ø Q max-orifice Ø 9 Q max-orifice Ø Q max-orifice Ø Ø η% Ø 8 H [m] Ø Ø 9 Ø 9 P [kw] Ø Ø 9 8 PSH-value are measured quantity; N safety margin of, m is required NPSH [m] Ø 9 Q max-orifice Ø Q min-orifice Ø PSH-value are measured quantity; N safety margin of, m is required NPSH [m] Ø Q min-orifice Ø Ø 9 Ø PSH-value are measured quantity; N safety margin of, m is required 8 P [kw] 7 8 9 P [kw] 7 Ø 9 Ø Ø Inducer Ø 9 Ø 9 NPSH [m] Inducer Ø 8 Ø Impeller 9- mm Ø, Width mm Hermetic Impeller 9- mm Ø, Width mm 8 9

P u mp Materials/Pressure Ratings/Flanges S eries Operating Temperature Casing JS Impeller JL Bearings./carbon Shaft. Power up to kw Stator can.7 Rotating speed 8 rpm or rpm Gaskets AFM * Voltage Pressure rating PN **, 8,,,,, or V Flanges according DIN, PN, Form N, groove design according DIN Frequency or Hz (frequency regulation possible) Enclosure Motor/Rotor IP / IP7 Temperature range C to + C *** Canned Motors * non asbestos ** PN on demand *** further temperatures on demand CNF-Design Type CNF CNF CNF CNF Motor Pump data Motor data Q min. required m / h Q max. permissible m / h Power,,, Weight kw Rated current at V / Amp. kg, 7, 8,,,, 9 8, 8, 9 8,,, 7,,, 77 8, 8, 9 9 CKPx,,,,,, 77,,, 8 8, 8, 9 9 CKPx,,, 8,,, 8 8, 8, 9 9 CKPx,,, Hermetic 7 C N F

List of parts CNF. impeller 9. bearing sleeve volute casing wear ring insert 8 stator can 8 motor casing. bearing bush. 89 rotor shaft cover 9. bearing sleeve. auxiliary impeller 8 rotor core wear ring 78 filter. distance sleeve 8 Hermetic.. joint ring 8. motor casing cover. 8 bearing insert. 8 stator core. bearing bush

P u mp Dimensional drawing for motor type:, /, /, S eries Dimensional drawing for motor type: 8, / CKPx, ➊ L L b ➋ b DND DND ➌ ➋ ➊ DNS DNS ➍ ➊ Cable U, V, W + ➊ Cable U, V, W + H V V h ➋ W protective conductor y x, mm, Cable for winding protection x, mm, cable number +, cable length, m Pressure gauge G / h ➋ H h V h W ➌ ➍ protective conductor y x mm, cable length, m Cable for winding protection x,7 mm, cable number +, cable length, m Pressure gauge G / Adaptor for connection of temperature monitor closed with plug DIN 9, G / CNF-Design CNF CNF CNF CNF CNF CNF CNF CNF, to, 8,,/, 8,/,,/, 8,/,, 8,/, Length/L 7 9/ 9/ 9/ Width/W /9 /9 /9 Height/H 9 9 Dimension h h 8 8 8 8 b 8 8 v 8 8 8 8 DNS 8 8 8 8 DND Hermetic 9 C N F

M u ltistage C anne d M otor P u mps General The and R range of HERMETIC pumps are completely closed. They operate using the canned motor principle which removes the need for any shaft seal. The and R ranges have been developed especially for the refrigeration applications, their features include: Low NPSH values Pump built in two to five stages to suit the application Able to pump m/h with a suction head of only, m Suitable for pumping ammonia, freons and other refrigerants The machines were examined by several classification companies and also have approval for use on ships. The R range is a special version of the range designed for compact plants with small collecting vessels. The design enables: Space saving by mounting the pump directly under the vessel Escaping of gas through the suction port, allowing shorter re-starting times The hydraulic data and NPSH value are identical to the H e r m e t i c Design The pumps use multistage impeller mounted directly on an integral induction motor. Operating range Capacity Q: max. m/h Head H: max. m.c.l. Application sector Liquid gases as e.g. R 77 (NH), R (Frigen), CO, R a, R a, R, R, baysilone (M, M), methanol, silicon oil KT, syltherm, lithium bromide. In principle the refrigeration pumps are suitable for use with all refrigerant liquids. Please consult for any fluids not listed above.

P u mp C A M Return of partial flow in between stages Pressure-Temperature-Diagram ➊ ➌ Bearings Slide bearings are lubricated by the processed liquid radially guide the pump shaft and the rotor shaft. This guiding, however, takes place only during the starting phase and the stopping phase, since the guiding function is hydrodynamically taken over by the rotor after the nominal speed of the canned motor has been reached. The axial thrust of our pumps is hydraulically balanced. Safety Devices and Monitoring We recommend to protect HERMETIC pumps against any extrem flow conditions by means of two orifices. Orifice (Qmin) ensures the minimum flow rate required for the dissipation of the motor heat loss. Orifice (Qmax) ensures the minimum differential pressure in the rotor chamber needed for stabilising the hydraulic axial thrust balance and for avoiding the evaporation of the partial flow. Moreover, this orifice prevents an interruption of the flow of discharge if only a certain minimum suction head is available. Alternatively to orifice (Qmax) a constant flow regulator can be installed (see page -). Δp Operation The partial current for the cooling of the motor and for the lubricating of the bearing is taken from the last impeller on the discharge side and led through the motor space. It is led back through the sleeve shaft not to the suction side of the pump but between two impellers in a region with increased pressure. The point, which corresponds to the highest heating in the pressure-temperature-diagram, is sufficiently distanced from the vapour diagram, in order to avoid a boiling out inside the pump. S eries ➋ Δt ➊ Pressure ➋ Temperature ➌ Vapour pressure curve Figure Hermetic

Performance Curve Performance Curve and R Q [m/h] 7 Performance Curve 8 U/min Ø9 8 Q [m/h] 8 7 Ø 9, 7 η% η% H [m] Performance Curve 8 U/min 9 Ø H [m] -stage Ø, -stage Q max-orifice Q max-orifice Ø, PSH-value are measured quantity; N safety margin of, m is required,8, PSH-value are measured quantity; N safety margin of, m is required,8, NPSH [m], NPSH [m],,, P [kw] Performance Curve Q [m/h] 8 Performance Curve 8 U/min Ø 9, η% Ø 9, 8 -stage Ø Q max-orifice PSH-value are measured quantity; N safety margin of, m is required P [kw] H e r m e t i c 8, P [kw], 7,8 NPSH [m] H [m]

P u mp Materials/Pressure Ratings/Flanges S eries C A M / C A M R Operating Temperature Casing JS Suction cover (Suction casting R ) JS Stage casing (,, R ). Stage casing ( ) JS Diffuser insert (Diffuser ) JL Impellers JL Bearings./carbon Shaft. Stator can.7 Gaskets AFM * Pressure rating PN ** Flanges according DIN, PN, Form N, groove design according DIN Temperature range C to + C *** Canned Motors Power up to 9 kw Rotating speed 8 rpm or rpm Voltage, 8,,,,, or V Frequency or Hz (frequency regulation possible) Enclosure Motor/Rotor IP / IP 7 * non asbestos ** PN on demand *** further temperatures on demand / R-Design Type Motor Pump data Motor data Q min. required m / h Q max. permissible m / h Power Weight kw Rated current at V / Amp. kg /,,,,,7 7 /,,,,7 8 /,,,,7 9 /,,,,7 (R) /,, 7, 8 (R) /,,, 7, (R) /,,,, (R) /,,, 7, (R) /,,,, 8 (R) /,,, 7, (R) /,,,, 7 (R) /,,,, 77 / 8, 8, 9 / CKPx,,, / CKPx 9, 9, 8 9 / 8, 8, 9 8 / CKPx,,, 8 / CKPx 9, 9, 8 / CKPx,,, 8 / CKPx 9, 9, 8 Hermetic

List of parts /. impeller. suction cover. 7. diffuser insert 8 stage casing pump casing.. impeller 7. diffuser insert... impeller motor casing cover 78 filter. bearing bush 8. motor casing cover H e r m e t i c 8 rotor core 9. bearing sleeve 8 stator core 8 stator can 89 rotor shaft 8 motor casing. bearing bush 9. bearing sleeve.

P u mp S eries C A M / C A M Dimensional drawing for motor type:, /, /, /, L ➊ Cable U, V, W + protective conductor y i x, mm, cable length, m ➋ Pressure gauge G / DND ➋ ➊ h DNS H h W -Design -Design /-stage /-stage,,,, Length/L 9 7 7 Width/W Height/H Dimension /-stage /-stage /-stage /-stage,,/,,/,,/,/, Length/L 77 8 9 Width/W 8 8 8 8 Dimension /-stage /-stage Height/H h 9 9 9 9 h h h i 8 9 i 7 7 8 DNS DNS DND DND Hermetic

List of parts R. impeller suction casing 7. diffuser insert inlet ring 8 stage casing.. impeller. impeller pump casing.. 7. diffuser insert. motor casing cover 78 filter. bearing bush 8. motor casing cover H e r m e t i c 8 rotor core 9. bearing sleeve 8 stator core 8 stator can 89 rotor shaft 8 motor casing. bearing bush 9. bearing sleeve.

P u mp S eries Dimensional drawing for motor type:, /, /, ➊ Cable U, V, W + protective conductor y x, mm, cable length, m L ➋ Pressure gauge G / ➌ Drain with screwed plug G / (optional) i DNS DND ➋ ➊ h H h W ➌ R -Design R /-stage R /-stage,,/,,/, Length/L 9 9 7 77 Width/W 8 8 8 8 Height/H h h i 8 DNS DND Dimension R R /-stage /-stage,/,/, Hermetic 7 C A M R

List of parts 7. diffuser insert. impeller pump casing. 7. diffuser insert 78 filter 8 stage casing.. impeller. 8. motor casing cover. motor casing cover suction cover. bearing bush. impeller 8 H e r m e t i c 8 rotor core 9. bearing sleeve 8 stator core 8 stator can 89 rotor shaft 8 motor casing. bearing bush 9. bearing sleeve.

P u mp S eries Dimensional drawing for motor type: 8, / CKPx, / CKPx 9, ❶ Cable U, V, W + protective conductor y, x mm, cable length, m ➋ Cable for winding protection, x,7 mm, cable length, m ➌ Pressure gauge G / L i DND ➌ ➋ ➊ h H DNS h W -Design /-stage /-stage /-stage /-stage /-stage /-stage /-stage /-stage 8, CKPx, CKPx 9, 8, CKPx, CKPx 9, CKPx, CKPx 9, Length/L 97 77 99 7 7 8 Width/W 9 9 9 Height/H 8 8 8 8 8 8 h 7 7 7 7 7 7 h i 8 8 8 98 98 DNS DND Dimension Hermetic 9 C A M

C onstant flo w R eg u lator General The constant flow regulator has been developed especially for refrigeration plants. These valves facilitate a safe operation of pumps in a sphere, which normally is impossible for pumps with Qmax-orifice. Figure shows the additional operational range which is obtained by the application of a constant flow regulator instead of a Qmax-orifice. Often a smaller pump, more economically priced, can be installed. Operation The constant flow regulator must remain full of fluid during system operation. The operation of the valve is dependent on the characteristics of the flowing media. It is therefore important that when ordering a valve, complete fluid specifications are included. Specific gravity is the most important value for the correct design of a valve. Maintenance There is no need for regular maintenance of the constant flow regulator and no readjustment is required. Spare cartridge assemblies may be ordered when required. H e r m e t i c

A ccessories Discharge head H [m] Performance curve A B Pressure differential control range (= 8 bar) Discharge rate after constant flow regulator ➋ C ➊ +/- % ➊ Pump pressure 8 bar ➋ Pump pressure 8 bar Figure Application sector Constant flow regulators are intended to be installed at the outlet of refrigerant liquid pumps. These regulators accurately control the flow rate and enable pumps to safely function in a range not normally available to pumps using discharge orifices. They enable pumps to operate closer to their unrestricted pump flow curve but not to exceed the calibrated quantity of flow. They will prevent a pump from operating in a region which exceeds its motor horsepower rating and required NPSH. (see diagramm at Figure ) Principles of operation Flow limitation is achieved by specially shaped ports in a spring-loaded, moving piston (Figure ). Due to the pressure differential before and behind the piston, it oscillates which in turn changes the exposed area of the orifice. As the pressure differential increases, the cartridge moves to counterbalance the spring force. This displacement moves part of the variable port past the stationary orifice plate. If the pressure differential decreases, the cartridge oscillates in response to the pressure differential which in turn increases the exposed area of the orifice. If the pressure differential exceeds a specified maximum (pressure differential control range = 8 bar), the spring is fully compressed and the valve acts as a fixed orifice device. This also operates if the orifice. If the pressure differential exceeds a specified maximum (pressure differential control range = 8 bar), the spring is fully compressed and the valve acts as a fixed orifice device. This also operates if the pressure drops beyond the required minimum. Functional-Diagram Valve Range A: Below control range, cartridge acts as a fixed orifice device, flow varies below rate required. A A B A Range B: Within control range, cartridge modulates, flow is maintained at fixed flow rate +/ %. B C B C Range C: Above control range, cartridge is fully compressed, flow increases as differential pressure increases. C Figure Hermetic Capacity V [m/h]

List of parts Hexagon bolt x M x (DN ) x M x (DN ) x M x (DN ) DIN EN (DIN 9) Constant flow regulator insert Counter-Flange, DIN DN, PN DN, PN DN, PN Casing for the constant flow regulator Insert B, DN Insert K, DN and DN Hexagon nut x M, DIN EN (DIN 9) Counter-Flange, DIN DN, PN DN, PN DN, PN with groove acc. DIN y x The valve is available for the following flow rates: Model NW NQL---8 NQL--8-8 NQL---8 NQL---8 H e r m e t i c for pump type Dimension x/y max. flow rates for HO / R / 7 9,99 m/h / CNF / CNF / 9 CNF / CNF 7 / / CNF / CNF / 9 CNF / CNF 7 / / 9 CNF / CNF 7 / 9, m/h, m/h, m/h

A ccessories Orifice Plates It is possible to protect a HERMETIC pump from extreme flow conditions by installing orifice plates. The Qminorifice guarantees the necessary flow for the motor cooling and the bearing lubrication. It also allows correct venting of the pump at standstill. The Qmaxorifice ensures that the minimum differential pressure is maintained in the rotor space. This is necessary for the stabilization of the hydraulic axial thrust compensation and for the avoidance of the partial current vaporization. You can see the installation of the orifices on page. Inducer Inducers are axial impellers, which are installed closely in front of the first impeller of a centrifugal pump on the same shaft and which cause an additional static pressure in front of the impeller (Figure ). They are particularly used where the NPSHA is not sufficient in order to reduce the NPSHR value of the pump. In many cases inducers are also used preventitively if the resistances of the suction line cannot be determined exactly or if the suction head is unpredictable, or if there is a change of the overpressure above the vapour pressure of the liquid. Furthermore inducers are particularly suitable for the transport of liquids, which are affected with disolved gases. In both cases the inducer can serve to avoid cavitation and minimum capacity. Figure Hermetic

Our products comply with: n Explosion protection acc. to ATEX / UL / CQST / CSA n VOC directive 999//EC n TA-Luft n IPPC directive n CE n RCCM, level n Rosgortechnazdor HERMETIC-Pumpen GmbH is certified acc. to: n ISO 9: n GOST R n ATEX 9/9/EG n AD HP / TRD n DIN EN 79- n KTA, QSP a Convincing service. Important features are readiness, mobility, flexibility, availability and reliability. We are anxious to ensure a pump operation at best availability and efficiency to our customers. Installation and commissioning: n service effected on site by own service technicians Spare part servicing: prompt and longstanding availability n customized assistance in spare part stockkeeping Maintenance and service agreement: n concepts individually worked out to increase the availability of your production facilities n Training and workshops: extra qualification of your staff to ensure the course of your manufacture n Repair and overhauling: professional repairs including test run executed by the parent factory n or executed by one of our service stations worldwide n KÄLTE / E / / 8 H e r m e t i c HERMETIC-Pumpen GmbH Gewerbestrasse D-799 Gundelfingen phone +9-7-8- fax +9-7-8-8 hermetic@lederle-hermetic.com http://www.lederle-hermetic.com