Water-repellent coating in in-built condensers

[0001] The present invention relates to a method for producing a condenser for a heating installation. Furthermore, the invention relates to a device for coating a mounted condenser pipe with a hydrophobic coating.

Background of the invention [0002] The steam turbine uses total water vapor enthalpy to convert thermal energy, for example energy of atom, carbon or other energy carriers, into mechanical energy. In this process, liquid steam, e.g. water, is used to generate steam in a steam generator and feed it to the turbine. This turbine can use the steam enthalpy difference to generate mechanical energy. A condenser or steam condenser is placed behind the turbine to carry out isobaric condensation of steam.

[0003] Surface condensers are known for condensing steam in steam turbine installations, wherein surface condensers have a large number of uncoated pipes. On the condenser tubes, which are filled with a cooling working medium, film-like condensation usually occurs, so that the liquid vapor changes into a liquid state.

[0004] Furthermore, the condenser tubes may be hydrophobically coated to ensure a deliberate transition from film condensation to drip condensation. By means of drop condensation, an increase in heat transfer can be achieved, which results in an improvement of the heat transfer coefficient by approx. 20%. This, in turn, leads to improved capacitor efficiency (less temperature build-up) or to reduced costs and reduced installation space with the same temperature build-up.

[0005] DE 10 2007 008 038 A1 discloses a method by which a heat exchanger tube is spray-coated with a hydrophobic layer. The hydrophobic layer can be sprayed through the nozzles onto the condenser tubes, the nozzles having flexible leads and being placed side by side and fixed in an articulated chain. In particular, the nozzles are mounted on the lances and can be inserted into the tube bundle. In addition, the device has a fastening assembly that can be attached to the support plate of the condenser tube bundle and dismantled.

[0006] DE 10 2007 015 450 A1 discloses a coating for steam condensers. This coating consists in particular of a hydrophobic coating. The coating is applied by the sol-gel method.

[0007] GB 24 28 604 A discloses an antifouling coating on a heat exchanger. The coating can be applied, for example, by the sol-gel method or by immersion.

Presentation of the invention [0008] The object of the invention is to propose a capacitor with better efficiency.

[0009] This task is solved by the features of the independent claims, in particular by means of a method of producing a condenser for a heating installation, and a device for coating the hydrophobic coating of the mounted condenser tube.

[0010] According to a first exemplary embodiment of the present invention, a method for producing a condenser for a heating installation is described. The condenser tube is mounted in the support for the condenser condenser harness. The mounted condenser tube is coated with a hydrophobic coating.

[0011] According to a further exemplary embodiment, a device is proposed for coating the mounted condenser tube with a hydrophobic coating as described above. The device has a spray head for coating the mounted condenser pipe with a hydrophobic coating.

[0012] According to a further exemplary or non-claimed embodiment of the present invention, a condenser for a heating installation is proposed. The capacitor is prepared as described above. The condenser has a bracket with a condenser tube mounted, the condenser tube being mounted has a hydrophobic coating.

[0013] The term "condenser tube bundle" can be understood to mean one condenser tube or a large number of condenser tubes that are held relative to each other in a certain distance in a support (condenser tube support) and form a condenser tube assembly or condenser tube bundle. The steam to be cooled can, for example, fall on a bundle of condenser tubes, so that steam can flow through the bundle of condenser tubes, flowing around the individual condenser tubes. The support can also be designed to hold individual condenser tubes at a certain distance, so that water vapor can flow between the condenser tubes and can be chilled by them. The bracket may, for example, consist of tube plates and supporting walls, which have holes and fixing units on which individual condenser tubes can be mounted.

[0014] The term "hydrophobic" or "hydrophobic coating" can be understood to mean a surface that is water repellent or on which drip condensation may occur. In addition, the term "hydrophobic coating" can also be understood below to include a coating that exhibits oleophobic properties, i.e., oil-repellent. The hydrophobic coating has a contact angle for liquid drops above 90^about. Contact angle for hydrophobic coatings can reach up to 130^about. Using structured surfaces, a superhydrophobic effect with a contact angle greater than 130 can be obtained^about or greater than 160^about (degrees) (e.g. lotus effect). The contact angle defines the angle between the surface of the coating and the vector running tangentially to the liquid droplet at the point of contact of the drop with the surface of the structural element. With a contact angle above 90^about in the case of a water drop, a drop shape forms on the surface, so that with a contact angle above 90^about drip condensation can be realized.

[0015] Typically, the condenser tubes are coated prior to installation in the bracket and, after applying the coating, slid into the bracket for the condenser tube bundle. The insertion or assembly of already coated condenser pipes may, however, damage the hydrophobic coating. Hydrophobic coatings are sensitive, therefore they show low abrasion resistance, and the risk of violation of hydrophobic coatings on condenser pipes during assembly is high. It may be particularly desirable to cover the condenser pipes with superhydrophobic layers (e.g. "lotus effect" coatings), whereby such superhydrophobic layers are particularly sensitive to mechanical stress, therefore subsequent assembly of coated condenser pipes leads to a high risk of coating damage . In addition to sliding the condenser tubes in addition, damage to the coating can also be caused by the way the condenser tubes are secured to the condenser tube bundle support. The condenser pipes are welded to the bracket, for example, whereby a hydrophobic coating may be breached. In addition, replenishing hydrophobically coated condenser pipes by replacing the pipes requires a high level of maintenance, which means that maintenance and set-up times are long.

[0016] By means of the claimed production method, a hydrophobic coating is applied to the mounted condenser pipe. In other words, a hydrophobic coating is applied to the condenser tube, already attached to the condenser tube bundle. In this way, it is possible to process the condenser that is being produced in a single coating process, so that the condenser condenser pipes can be coated with a hydrophobic coating in one operation, which reduces production time. In addition, with subsequent condenser maintenance processes, you can renew the hydrophobic coating without removing the individual condenser pipes.

[0017] In the claimed method of producing a condenser, it is furthermore possible to only coat part of the condenser tubes in the mounted state, while the other part of the condenser tubes can be left uncoated. For example, the outermost tubes of a condenser tube bundle contribute most to the capacitor's efficiency. Therefore, the advantages of the invention can already be achieved in that the condenser tube bundle bracket is mounted first with the extreme condenser tubes and coated with a hydrophobic coating. Thus, at least the outermost tubes of the condenser tube bundle have a high quality hydrophobic coating. Since these extreme capacitor pipes located on the edge of the bracket provide the highest capacitor efficiency, it is particularly advantageous if a high quality hydrophobic coating is used in these condenser pipes. In this way, higher capacitor performance can be achieved without dismantling the condenser pipes.

[0018] Furthermore, there is a better serviceability and better retrofit capability (can be maintained or retrofitted). This can be an important factor for the power plant user, because a short downtime of the steam turbine or condenser without significant assembly work leads to a significant improvement in efficiency. In addition, an attractive business field for servicing can be created for the steam turbine manufacturer.

[0019] The application of the coating to the condenser tubes in the mounted state also allows the selection of the coating without taking into account the mounting requirements. It is in the case of coated condenser pipes that one has to consider that, for example, the coating contacts the mounting means to the bracket, which leads to wear of the coating. The complex process of inserting condenser pipes through a series of mounting holes has so far ruled out the possibility of using less stable mechanically structured hydrophobic coatings. Subsequent coating of the mounted condenser pipes by means of the claimed method of production thus allows the application of hydrophobic coatings to the condenser pipes, which allows further improvement of condensation parameters.

[0020] Furthermore, coating the mounted condenser tube with a hydrophobic coating includes at least positioning the spray device on the bracket or relative to the bracket. With the help of a spraying device, the hydrophobic coating is then sprayed to cover the mounted pipe with a hydrophobic coating. With the help of spray varnishing, it is possible to obtain an extremely thin and evenly applied hydrophobic coating on the mounted condenser pipe due to the very fine spraying of the hydrophobic coating mass.

[0021] Furthermore, the step of coating the mounted condenser tube with a hydrophobic coating includes moving the spray device during spraying at a uniform feed along the expansion direction of the mounted condenser tube. This allows for automatic even spraying or coating of the installed condenser pipe. It is during manual application of the coating that irregularities can be caused by spray application of the hydrophobic coating due to irregular manual feed, as a result of which layers of different thicknesses are formed on the condenser tube. By using a spraying device that ensures an even feed, you can achieve a set and even thickness of the hydrophobic coating layer, which in turn allows you to achieve the desired and improved condensing performance of the condenser tube. In addition, a multiple feed with uniform feed allows the application of a large number of layers of hydrophobic coating. Thus, for example, a hydrophobic coating may consist of 10, 12 or more sub-layers. In addition to uniform feed along the expansion direction of the mounted condenser, even feed perpendicular to the expansion direction of the mounted condenser tube is also possible.

[0022] According to another exemplary embodiment of the method, the condenser during coating is mounted on a heating installation and, e.g., active before the coating process. The power plant user can therefore, without draining the condenser tubes, and therefore with minimal effort, repair or apply a hydrophobic coating on the mounted condenser tube. You can avoid removing the condenser tube, and thus interrupting the capacitor.

[0023] According to another exemplary embodiment, the mounted condenser tube is coated with a hydrophobic coating by painting. The method of coating by painting can easily and quickly cover a condenser pipe with a hydrophobic coating. For example, brush-type devices can be used in the method of coating by painting.

[0024] According to another exemplary embodiment, the spray device has a spray head, wherein coating the mounted condenser tube with a hydrophobic coating further includes the step of introducing the spray head into the bracket to coat the mounted condenser tube with a hydrophobic coating.

[0025] By "injecting" the spray head into the bracket it can be understood that in addition to spraying the outer condenser tubes of the condenser tube bundle, there is also the possibility of coating the interior of the condenser tube bundle. The spray head can be inserted into the support in such a way that it can be routed at intervals between the condenser tubes, and thus coat the condenser tubes lying inside, which, for example, do not come into direct contact with the surrounding condenser tube bundle. This allows the condenser pipes, which are hidden in the mounted state, to be covered with a hydrophobic coating when assembled, so that it also does not have to be necessary to dismantle those capacitor tubes lying inside. The spraying device can be located, for example, on or in the support of the condenser tube bundle and by means of uniform feed along the condenser tubes spray the coating.

[0026] According to another exemplary embodiment, the step of coating the mounted condenser tube with a hydrophobic coating further includes coating the mounted condenser tube by electrostatic spray painting. For example, the degree of coverage can be improved by using electrostatic spraying by electrostatic spray painting. In the electrostatic spray painting process, you can charge an electrostatically sprayed hydrophobic coating mist, for example 35kV (kilovolt), 40kV or 50kV, during application and spray onto the grounded condenser pipes. The condenser pipes are connected to the earth potential. For example, the condenser tube bundle support may be a metal conductor, thus used as an electrically conductive structural component. Condenser or electrically conductive pipes themselves, structural structural elements can be provided with a connection to the ground (grounding, ground potential). The hydrophobic coating can, for example, be electrostatically charged by means of a voltage source. Electrostatic spray varnish therefore has the advantage that the hydrophobic coating is evenly distributed, for example by spray application, and in addition the loss of material of the hydrophobic coating can be reduced. In addition, when applying a hydrophobic coating to condenser pipes by means of electrostatic spray painting, it is possible to coat the condenser pipes from all sides. For example, if the spray head is located on one side of the condenser tube, then the spray mist can nevertheless accumulate on the opposite side of the condenser tubes as a result of electrostatic charge, which allows the hydrophobic coating to be carried out also in opposite places of the condenser tubes. With electrostatic spray painting, it is possible to achieve a given, thin and even hydrophobic coating on the condenser pipes with the appropriate selection of the dosage of the hydrophobic coating and the appropriate selection of the feed or static voltage applied, which in turn enables achieving the given hydrophobic properties on each of the condenser pipes.

[0027] According to another exemplary embodiment, the hydrophobic coating on the mounted condenser tube is crosslinked by means of UV curing, the "Dual Cure" method and / or thermal curing.

[0028] The term "crosslinking" can be understood to mean joining the coating to the surface of condenser tubes. The term "crosslinking" can mean that the coating is permanently bonded to the surface of the condenser tubes. This is possible, for example, due to the fact that the coating particles connect to the atoms / particles of the surface of the condenser tubes or that the coating particles enter the voids of the surface of the condenser tube, thus creating a permanent connection.

[0029] In the case of UV curing, ultraviolet (UV) light is emitted by means of a UV radiator towards the coating, so that crosslinking of the coating occurs due to the excitation of the particles in the coating and due to the increase in temperature.

[0030] Another cross-linking technology by UV cure is the "Dual Cure" method, in which cure is first initiated by UV radiation, and then the hydrophobic coating is completely cured at room temperature, whereupon crosslinking occurs.

[0031] Furthermore, crosslinking by curing under the influence of heat energy can be described by the term "thermal curing". Temperature ranges for thermal curing may be between 50^aboutC to 100^aboutC or in a range between 100^aboutC and 200^aboutC, and also between 100^aboutC to 250^aboutC. Thermal energy can be provided, for example, by means of radiators, heating coils, resistance heating systems or warm air blowers. In addition, thermal energy for curing can be obtained with the help of a heating fluid in the condenser pipes, so that no other thermal energy sources need to be needed. On the other hand, the working fluid in the condenser tubes can be drained to avoid adverse heat capacity on the fluid-filled tube.

[0032] According to another exemplary embodiment, the sol-gel method is used in the step of coating the mounted condenser pipe with a hydrophobic coating. For sol-gel coating, hydrophobic coatings that have a sol-gel structure are used. Such sol-gel hydrophobic coatings are based on hybrid polymers that have a network structure with organic and inorganic components. Organically modified metal oxides such as, for example, Si, Ti, Zr or Al alkoxylates can be used as starting material for the production of such sol-gel coatings. Preferably, Si alkoxylates are used as precursors that have, for example, the following chemical structure:

Xn - Si - (OR) 4 - n where:

X = organic alkoxylate modification

R = alkyl (e.g. methyl, ethyl) or aryl (e.g. phenyl) [0033] X (organic alkoxylate modification) may be a reactive or non-reactive side chain. The coating is produced by hydrolysis and condensation of metal alkoxides. Organic metal oxide modification can affect the coating properties. Hydrophobic side chains X (e.g. alkyl chains, alkyl groups, fluoro-alkyl chains, siloxane groups) reduce the surface energy of the coating and cause the effect of water repellency with water (hydrophobic) and oil (oleophobic). Organic modification may show sufficient stability under steam conditions.

[0034] The described hydrophobic sol-gel based coating material can be further modified by incorporating surface treated particles at the nano or micro scale, which allows, for example, to improve mechanical abrasion resistance or corrosion resistance.

[0035] Hydrophobic sol-gel coatings can be applied to the substrate (condenser tube) by the sol-gel method, for example using wet chemical methods such as spraying, dipping, pouring, roller or brush painting. The coatings are then cured or thermally crosslinked. For example, the temperature ranges of the crosslinking step described above can be used, but curing temperatures in the range of room temperature to 400 are also possible.^aboutC (Celsius). Higher curing temperature above 400^aboutC can lead to the formation of a glass-like layer, with hydrophobic properties being reduced. In addition, short chain side groups such as, for example, X = methyl groups, aryl groups, have sufficient thermal stability. In addition, a layer thickness of 100 nm (nanometers) to 100 μm (micrometers) can be achieved.

[0036] The hydrophobic coating on the mounted condenser tube can be applied by the sol-gel method in such a way that the contact angle of the hydrophobic coating is, for example, about 90^about (degrees), 100^about or 120^about. Compared to rough metal surfaces or condenser pipe surfaces, as a result of using a hydrophobic coating with a contact angle between 90^about and 130^about, especially between e.g. 100^about and 120^about, approximately 20% more condensate is captured, which can significantly improve capacitor performance.

[0037] According to another exemplary embodiment, the condenser is a steam condenser and the heating installation is a steam turbine installation.

[0038] According to another exemplary embodiment of the present invention, the device for coating the mounted condenser pipe with a hydrophobic coating according to the method of manufacture described above has a positioning assembly for positioning the device relative to the condenser tube bundle support. In addition, the device has a displacement assembly for displacing the spray head along and / or transversely to the expansion direction of the condenser tube. The positioning assembly may, for example, be a stand-alone unit and be fixed relative to the bracket. On the other hand, the positioning assembly can be mounted on the support itself and hold the coating apparatus. The device for coating the mounted condenser pipe can be, for example, a spraying device.

[0039] Furthermore, the coating apparatus has a spray head for coating the mounted condenser tube with a hydrophobic coating. The spray head may consist of, for example, a nozzle that can apply a finely sprayed hydrophobic coating to the surface of the condenser tubes. The displacement assembly can be movably connected to the positioning assembly and displaced along a given linear direction of movement, so that a uniform application of a hydrophobic coating on the condenser tubes can be achieved by means of a spray head.

[0040] According to another exemplary embodiment of the device, the spray head is designed so that the hydrophobic coating is applied to the mounted condenser tube by means of electrostatic spray painting. For example, the spray head can be connected to a voltage source and thus electrostatically charge the spray of the hydrophobic coating.

[0041] According to another exemplary embodiment, the device for coating the mounted condenser pipe has a connecting pipe. The connecting pipe can connect the displacement assembly and the spray head. The connecting pipe has a spiral shape, the pitch of the spiral shape being adaptable to the radius of the condenser tube and to the spacing of the condenser tubes in the condenser tube bundle. In other words, the spiral shape of the connecting pipe describes the helical line, similar to a corkscrew. On the one hand, the pitch of the spiral shape can be set permanently according to the radii of the condenser tubes and to the spacing of the condenser tubes and by means of the rotation of the connecting tube the spray head is screwed in or rotated along the condenser tubes. The connection pipe can thus already be permanently adapted to the radii of the condenser tubes and the spacing of the condenser tubes during its manufacture. In another embodiment, the connecting pipe can be made of a flexible material or deformable material, such as, for example, rubber, so that when screwing into a bundle of condenser pipes, the connecting pipe is adapted to the radii of the condenser pipes and the spacing of the condenser pipes, thus forming a spiral shape . The adaptable connecting pipe makes it possible to cover the existing bundle of a large number of condenser pipes with a hydrophobic coating. Even condenser tubes lying inside a condenser tube bundle can thus be covered with a hydrophobic coating. Therefore, it is no longer necessary to disassemble the inner and thus hidden condenser tubes from the condenser tube bundle to provide a hydrophobic coating on the condenser tubes.

[0042] According to another exemplary embodiment, the condenser is in the form of a heating capacitor. The term heating condenser can be understood as a condenser that is supplied with a higher steam pressure to thereby shift the steam condensing temperature to higher temperature ranges. The high vapor pressure in the heating condenser can be generated, for example, such that high pressure and high temperature steam is taken from one stage of the heating plant turbine and then fed to the heating condenser. The proposed technical solution allows to reduce the temperature accumulation (i.e. temperature difference between primary and secondary return temperature) of heating capacitors (i.e. improve or reproduce their operation), as a result, with the same parameters of heating steam, a slightly higher temperature of the heat carrier (fluid in the heating network) can be achieved. On the other hand, with the same temperature build-up, a smaller heat exchanger surface can be used (saving costs and / or space) or the efficiency of an existing heat exchanger can be increased.

[0043] According to another exemplary embodiment, the condenser is in the form of a high-pressure heater or a low-pressure heater.

[0044] The low-pressure heater may, for example, be located upstream of the feed water tank, and from the so-called condensate pumps a working medium (e.g. water) is obtained in a condensed liquid state. In addition, steam steam under pressure can be taken from steam turbines and fed to a low pressure heater. In this way, the temperature level of the working fluid in the low-pressure heater increases, and hence in the feed water tank behind it. This increase in temperature increases the efficiency of the steam cycle in the heating system. Also here, with the help of the new solution, improvement / reconstruction of the operation and / or reduction of costs and / or increase of the device efficiency is achieved.

[0045] The high pressure heater may be located between the feed water tank and the steam generator of the heating installation. As with the low-pressure heater, hot steam is supplied to the high-pressure heater from steam turbines under (higher) pressure. In this way, the energy level, especially the temperature level, of the feed water steam entering the generator increases. This allows to increase the efficiency of the steam cycle in the heating system. Improvements in performance, cost and / or performance can be achieved in a similar manner to a low pressure heater.

[0046] According to another exemplary embodiment of the condenser, it is used in a heat and power plant heat and power plant. The combined heat and power plant is used to generate electricity and heat using the combined energy management process. The separated heat from the steam circuit in the CHP plant can be removed through a condenser (e.g. in the form of a heating condenser) or another heat exchanger to the working medium in the heat transfer circuit. Therefore, in a power plant using the combined energy management process, unused waste heat can be directed to a remote heat transfer system for further use.

[0047] It is pointed out that embodiments of the invention have been described with reference to various objects of the invention. In particular, some embodiments of the invention with claims in the device category and other embodiments of the invention with claims in the category of method are described.

Brief Description of the Drawings [0048] In the following, for further explanation and better understanding of the present invention, embodiments will be described with reference to the accompanying drawing. They show:

1 is a schematic view of a condenser tube bundle with a hydrophobic coating according to an embodiment of the present invention;

Fig. 2 a top view of the condenser tubes in a condenser tube bundle according to an embodiment of the present invention; and Fig. 3 an exemplary embodiment of condenser tubes that are treated by electrostatic spray painting.

[0049] Detailed description of exemplary embodiments.

The same or similar components have the same reference numerals in the figures. The figures in the figures are schematic and not true to scale.

[0050] Fig. 1 shows an exemplary embodiment of a condenser 100, e.g. a steam condenser 100, for a heating installation, for example a steam turbine installation. Capacitor 100 can be coated with a hydrophobic coating using the method of manufacture described. The capacitor 100 has a support 105 in which the mounted condenser tubes 101 are mounted. The mounted condenser tube 101 has a hydrophobic coating.

[0051] According to the method for producing the condenser 100 for a steam turbine installation, the condenser tube 101 is first mounted in the bracket 105 for the condenser tube bundle 203 of the condenser 100. The mounted condenser tube 101 is covered with a hydrophobic coating.

[0052] A support 105 may be used to hold and fix each of the condenser tubes 101, so that a large number of condenser tubes 101 can be formed into a bundle of 203 condenser tubes. The condenser tube bundle 203 has extreme condenser tubes 101 and condenser tubes 101 inwardly located that do not come into contact with the surrounding condenser tube bundle 203.

[0053] The mounted condenser pipes 101 have, during the operation of the condenser 100, a cooling fluid, e.g. cooling water, in order to cause condensation of steam by cooling the steam flowing past them. As a result of the hydrophobic coating of the condenser tubes 101 installed, drip condensation of the water vapor flowing past them occurs here.

[0054] According to the production method described, the hydrophobic coating can be applied to the condenser pipes 101 by means of the spray device 106. The condenser pipes 101 are already in the state of application of the hydrophobic coating mounted on the support 105, so that no time-consuming dismantling is required to cover the condenser pipes 101 . Furthermore, damage to the hydrophobic coating of the condenser tube 101 during assembly is prevented.

[0055] The spray device 106 may have, for example, a spray head 102 with which a spray can be sprayed onto a condenser tube 101. A defined spray cone 104 is formed in this case. In addition to spraying the condenser tubes 101 using a spray head, it is also possible to coat with paint, e.g. with brush type devices.

[0056] On the one hand, the spray head 102 can be moved along the longitudinal direction (expansion direction) of the extreme condenser tubes 101, which allows at least the extreme condenser tubes 101 to be covered with a hydrophobic coating. In addition, the spray head 102 of the spray device 106 can be small enough, that the spray head 102 can be inserted into the distance of the condenser tubes. In this way, the spray device 106 can coat the hydrophobic coating at least also the second row of condenser tubes 101 in the condenser tube bundle 203.

[0057] In another example embodiment, the spray device 106 may have a connecting pipe 103, so that all condenser tubes 101 inwardly located within the bundle 203 can also be coated with a hydrophobic coating when installed. The connecting pipe 103 can have a spiral (helical) shape, the helix pitch can be selected so that it adapts to the radii r of the condenser tubes and the spacing a of the condenser tubes.

[0058] In this way it can be achieved that by rotating the connecting pipe 103 the spray head 102 is screwed into the bundle 203 of the condenser pipes. Thus, any inside condenser tube 101 can be coated with a hydrophobic coating.

[0059] Fig. 2 shows a top view of the mounted condenser tubes 101 in a condenser tube bundle 203. The condenser tube bundle 203 has, for example, a bottom 202 and a large number of retaining walls 201 to support the condenser tubes 101. The hydrophobic coating can be applied either along the longitudinal direction or along the transverse direction of the condenser tubes. Along the lateral or longitudinal direction of the condenser tubes 101, the spray device 106 may apply a hydrophobic coating either in one direction or alternately. Furthermore, the spray device 106 can be moved along the longitudinal or transverse direction of the condenser tubes 101. The spray device 106 may move the spray head, for example, alternately or alternately in the direction along the expansion direction of the condenser tubes 101 or along the transverse direction. It is also possible to mix both directions of movement (along the stretching direction and lateral direction). In this case, the spray device 106 can be moved, for example, along the positioning unit or the displacement unit and during movement the spray head 102 can rotate transversely to the direction of movement of the spray device 106 or make a tilting movement, so that it is possible to mix the two spray directions. This enables the continuous application of a hydrophobic coating.

[0060] Fig. 3 shows an exemplary embodiment of a structure for applying a hydrophobic coating by means of electrostatic spray painting. The condenser pipes 101 or bracket 105 may be electrically conductive, i.e. they may be elements 303 of electrically conductive structure. These electrically conductive structure elements 303 may be connected to earth potential 302. The spray device 106 and / or spray head 102 are connected to a voltage source 301, so that the spray mist of the hydrophobic coating can be electrostatically charged, e.g. 30 kV, 40 kV, 50 kV or 60 kV (kilovolt). As a result of the grounded condenser pipes 101, the electrostatically charged spray mist of the hydrophobic coating is attracted, whereby the spray mist is evenly deposited on the condenser pipes 101. By attracting an electrostatically charged spray mist, the hydrophobic coating can be extensively covered with a hydrophobic coating mounted condenser tube 101. Even if the spray head 102 applies spray mist to one side of the condenser tube, the spray mist can be attracted to the opposite side of the condenser tube 101 by electrostatic attraction which also creates a hydrophobic coating on the opposite side. In this way, even with hard-to-reach condenser pipes 101, an even hydrophobic coating can be achieved when installed.

[0061] By means of the present invention, a condenser bundle 203 can thus be created for a condenser 100 that has condenser tubes 101 mounted and hydrophobically coated. The coating of the condenser tubes 101 in an assembled condition allows the production of the condenser tube 203 to be accelerated, since the coating process does not need to be carried out separately for each condenser pipe 101, but once for all mounted condenser pipes 101. In addition, during the maintenance of the steam turbine already installed on the plant and the active condenser 100, the coating of the condenser pipes 101 can be carried out without removing the condenser pipes 101. Damage to the hydrophobic coating that occurs when mounting the capacitor tube 101 in the condenser tube bundle 105 of 203 condenser tubes can also be avoided because the condenser tubes 101 are coated with a hydrophobic coating only after the condenser tube 101 is mounted in the condenser tube bundle 105 of 203.

[0062] In addition, it should be noted that the term "includes" excludes other elements or steps, and the term "one" or "one" excludes a large number. References in the claims should not be construed as limiting.

Siemens Aktiengesellschaft

Proxy:

80P32262PL00

EP 2 184 115 B1