Dry vacuum pump cleaning method and dry vacuum pump cleaning device

Abstract

The present invention provides a cleaning method for a dry vacuum pump in which a deposit is accumulated, the cleaning method comprising: activation verification inspection to verify the feasibility of activation of the dry vacuum pump; a reproduction processing step performed when the activation of the dry vacuum pump is impossible; and a life extension processing step performed when the activation of the dry vacuum pump is possible or when the activation is made possible after the reproduction processing step. The cleaning method is characterized in that the reproduction processing step refers to a step for introducing a high-temperature fluid into the dry vacuum pump to remove the accumulated deposit, and that the life extension processing step refers to a step for introducing a high-temperature fluid into the dry vacuum pump in an activation state to remove the deposit accumulated inside the dry vacuum pump.

Description

[Technical field]

[0001] The present invention relates to a method for cleaning a dry vacuum pump used in a vacuum facility and a cleaning device for a dry vacuum pump used in the method. [Background technology]

[0002] Dry vacuum pumps are installed in the exhaust systems of vacuum equipment such as CVD equipment and etching equipment used to manufacture semiconductors and liquid crystal panels, etc. Since these dry vacuum pumps suck in post-reaction process gases exhausted from process equipment such as vacuum chambers, they are known to accumulate deposits of powder, liquid, or gel-like substances inside the pumps after long periods of use, and in the worst cases, become unable to start due to solidified deposits.

[0003] In order to avoid the above-mentioned problems, conventionally, dry vacuum pumps that are in operation are periodically removed and overhauled, but there is a problem in that such overhauls require a great deal of time and cost. Therefore, as a conventional technique that can solve such problems related to overhauls, for example, the following Patent Document 1 (JP Patent Publication No. 2021-195893) discloses a vacuum pump that rotates the rotor of a turbomolecular pump to exhaust gas, and that has a cleaning function unit for a cleaning function that cleans deposits in the vacuum pump and a deposit detection function unit for a deposit detection function that detects the deposits. According to this technique, it is possible to provide a vacuum pump that is capable of removing deposits without overhauling and is capable of detecting that the removal of deposits has been completed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-195893 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional techniques have the following problems. That is, when a cleaning function unit, a deposit detection function unit, or the like is added to a vacuum pump, even if there is no problem with the function of the vacuum pump itself, a situation may arise in which the use of the vacuum pump must be stopped if a trouble occurs in the cleaning function unit or the deposit detection function unit. In addition, a vacuum pump with various functions added has a complex structure, and if an overhaul becomes necessary, it will take more time and cost than a conventional vacuum pump. Ultimately, it is desirable to perform so-called swap maintenance, in which a vacuum pump in operation is replaced with a spare pump of the same type, rather than incorporating a maintenance mechanism in the vacuum pump itself. However, a method for cleaning a dry vacuum pump that can restore or extend the life of a dry vacuum pump that cannot be started due to solidification of deposits in a simpler manner comparable to that of an overhaul has not yet been realized.

[0006] Therefore, a primary object of the present invention is to provide a method for cleaning a dry vacuum pump, which can remove deposits that have built up inside a dry vacuum pump in a shorter time and more simply than an overhaul, thereby restoring the pump to its original condition or extending its life, and a cleaning device for a dry vacuum pump used in said method. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention provides a method for cleaning a dry vacuum pump having deposits accumulated therein, as configured as follows, as shown in FIGS. That is, the method includes a start-up confirmation test S3 for confirming whether the dry vacuum pump can be started, a regeneration process S4 which is executed when the dry vacuum pump cannot be started, and a life extension process S6 which is executed when the dry vacuum pump can be started or when the dry vacuum pump can be started after the regeneration process S4. The regeneration process S4 is a process of introducing a high-temperature fluid into the dry vacuum pump to remove the accumulated deposits. The life extension process S6 is a process of introducing a high-temperature fluid into the dry vacuum pump while the dry vacuum pump is started, to remove the deposits remaining inside the dry vacuum pump.

[0008] The present invention provides the following advantageous effects, for example. Either a regeneration process or a life extension process is selected and executed depending on whether the dry vacuum pump can be started due to deposits accumulated inside, so that deposits inside the dry vacuum pump can be efficiently removed.

[0009] In the present invention, the high-temperature fluid is preferably at least one fluid selected from the group consisting of air, nitrogen, oxygen, argon, hydrofluoric acid and chlorine trifluoride heated to 50°C or higher and 400°C or lower. In this case, it is possible to chemically or physically remove most of the deposits remaining in the dry vacuum pump. If the temperature of the high-temperature fluid is below 50°C, it may be difficult to heat the deposits to reduce their viscosity, and conversely, if the temperature of the high-temperature fluid exceeds 400°C, it may adversely affect the seals attached to the dry vacuum pump.

[0010] In the present invention, in the regeneration process and the life extension process, it is preferable to introduce active species into the inside of the dry vacuum pump in addition to the high-temperature fluid. In this case, the deposit is, for example, SiO 2 This can be particularly effective in removing deposits when the main component is a strongly adherent substance such as silicon dioxide. Furthermore, when introducing the high-temperature fluid into the dry vacuum pump, it is also preferable to vary the pressure of the high-temperature fluid, and it is also preferable to repeatedly start and stop the dry vacuum pump while introducing the high-temperature fluid into the dry vacuum pump.

[0011] The second aspect of the present invention, a "dry vacuum pump cleaning device", is a device for carrying out the above-mentioned method, and as shown in FIG. 3, for example, the dry vacuum pump cleaning device is configured as follows. The dry vacuum pump 12 is characterized by comprising an inlet pipe 14 connected to an intake port of the dry vacuum pump 12, an outlet pipe 16 connected to an exhaust port of the dry vacuum pump 12, a high-temperature fluid supply means 18 for supplying a high-temperature fluid into the dry vacuum pump 12 via the inlet pipe 14, an atmospheric pressure exhaust line 16a and a reduced-pressure exhaust line 16b formed by branching off the downstream end of the outlet pipe 16 and capable of switching the destination of gas, a vacuum pump 20 installed on the reduced-pressure exhaust line 16b, and a detoxification device 22 provided downstream of the atmospheric pressure exhaust line 16a and the reduced-pressure exhaust line 16b for detoxifying exhaust gas discharged from the dry vacuum pump 12.

[0012] In the present invention, it is preferable to further include active species supplying means 24 for supplying active species into the dry vacuum pump 12 through the inlet pipe 14 . It is also preferable to provide the outlet pipe 16 with a trap device 26 for trapping components other than the gas discharged from the dry vacuum pump 12 .

[0013] Furthermore, in the present invention, it is preferable to provide a heating device 28 for heating the dry vacuum pump 12 from the outside, and it is particularly preferable that the heating means of the heating device 28 be induction heating. It is also preferable to further provide a preheating chamber for preheating the dry vacuum pump 12 which will perform the next cleaning operation. Effect of the Invention

[0014] According to the present invention, it is possible to provide a method for cleaning a dry vacuum pump which can remove deposits that have built up inside a dry vacuum pump in a shorter time and more simply than an overhaul, thereby restoring the pump to its original condition or extending its life, and a cleaning device for a dry vacuum pump used in the method. [Brief description of the drawings]

[0015] [Figure 1] 2 is a flowchart showing an example of a method for cleaning a dry vacuum pump according to the present invention. [Diagram 2] 2A and 2B are flowcharts showing subroutines in FIG. 1, in which FIG. 2A shows the subroutine for the regeneration treatment step, and FIG. 2B shows the subroutine for the life extension treatment step. [Diagram 3] FIG. 1 is an explanatory diagram showing an overview of a cleaning device for a dry vacuum pump according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a flow chart showing an example of a method for cleaning a dry vacuum pump according to the present invention, and Fig. 2 is a flow chart showing a subroutine in Fig. 1. Fig. 3 is an explanatory diagram showing an outline of a dry vacuum pump cleaning device 10 according to an embodiment of the present invention. The dry vacuum pump cleaning device 10 according to the present embodiment is a device for regenerating and extending the life of a dry vacuum pump 12 having deposits accumulated therein, and as shown in Fig. 3, is roughly composed of an inlet pipe 14, an outlet pipe 16, a high-temperature fluid supply means 18, a vacuum pump 20, a detoxification device 22, and an active species supply means 24 that is provided as necessary, to which a control system, a cooling water system, and the like (not shown) are attached.

[0017] The inlet pipe 14 is connected to the intake port of the dry vacuum pump 12 installed in the cleaning chamber 32 covered by the hood 30, and serves to introduce a high-temperature fluid or the like into the dry vacuum pump 12. To this end, the downstream end of a fluid supply pipe 50 of the high-temperature fluid supply means 18, which will be described later, is connected to the inlet pipe 14. In addition, a pressure gauge 34 for measuring the internal pressure is attached to the inlet pipe 14.

[0018] The outlet piping 16 is connected to the exhaust port of the dry vacuum pump 12 mounted in a cleaning chamber 32 covered by a hood 30, and serves to transport the high-temperature fluid that has passed through the dry vacuum pump 12 and become exhaust gas, as well as deposits and the like that have been expelled from the inside of the dry vacuum pump 12 by the high-temperature fluid.

[0019] The outlet pipe 16 is branched at the downstream end to form two branches, one of which is an atmospheric exhaust line 16a and the other is a reduced pressure exhaust line 16b. A vacuum pump 20 is installed in the reduced pressure exhaust line 16b. A changeover valve 36 and a changeover valve 38 are attached to the atmospheric exhaust line 16a and the reduced pressure exhaust line 16b, respectively, and by switching these valves, it is possible to switch whether the exhaust gas or the like flows through the atmospheric exhaust line 16a or the reduced pressure exhaust line 16b. In the state shown in FIG. 3, the changeover valve 36 is closed and the changeover valve 38 is open, so that the exhaust gas or the like flows through the reduced pressure exhaust line 16b.

[0020] In this embodiment, a trap device 26, which will be described later, is attached upstream of the branch of the outlet pipe 16, and an outlet valve 40, which is closed when pressurizing the inside of the dry vacuum pump 12 to which the outlet pipe 16 is connected, is attached between the trap device 26 and the branch of the outlet pipe 16. Pressure gauges 42, 44 and 46 for measuring the internal pressure are attached to the trap device 26, the atmospheric pressure exhaust line 16a and the reduced pressure exhaust line 16b, respectively.

[0021] The trap device 26 is a device that captures deposits of powder, liquid, gel-like substances, etc. discharged from the dry vacuum pump 12 through the outlet piping 16 in its internal space to prevent them from flowing downstream of the outlet piping 16, and its interior is cooled by cooling water (not shown).

[0022] The high-temperature fluid supply means 18 is intended to supply a high-temperature fluid into the dry vacuum pump 12 having deposits adhered thereto via the inlet piping 14, and has a fluid heating device 48 equipped with a heat source such as an electric heater, and a fluid supply pipe 50 that delivers the high-temperature fluid heated by the fluid heating device 48 to the inlet piping 14.

[0023] The fluid to be heated by the fluid heating device 48 is preferably at least one selected from the group consisting of air, nitrogen, oxygen, argon, hydrofluoric acid, and chlorine trifluoride. Moreover, the temperature of the high-temperature fluid obtained by heating the fluid in the fluid heating device 48 is preferably within the range of 50°C or more and 400°C or less, as described above.

[0024] In the embodiment shown in FIG. 3, the fluid heater 48 is supplied with air (CDA; Clean Dry Air) and nitrogen (N 2 Specifically, CDA is supplied to the fluid heating device 48 through a CDA supply line 52 whose gas supply amount is controlled by a mass flow controller 52a, and N 2 N is supplied to the fluid heating device 48 via a supply line 54. 2 When CDA is supplied to the fluid heating device 48 through the CDA supply line 52, the on-off valve 52b is opened, and N 2 Supply line 54 supplies N to the fluid heater 48. 2 When supplying the gas, the on-off valve 54b is opened.

[0025] The abatement device 22 is a device that abatements the exhaust gas discharged from the dry vacuum pump 12 through the outlet piping 16, the atmospheric exhaust line 16a or the reduced pressure exhaust line 16b. This abatement device 22 may be of any type, such as a combustion type, a thermal decomposition type, a wet type, an atmospheric pressure plasma type, an adsorption type, or a water scrubber type, but considering the space efficiency and abatement efficiency of the device, it is most suitable to use an atmospheric pressure plasma type. In addition, reference numeral 56 in Fig. 3 denotes a pipe for releasing the exhaust gas that has been abatement-treated by the abatement device 22 into the atmosphere, and reference numeral 58 denotes a fan that sucks in the exhaust gas.

[0026] The active species supplying means 24 is provided as necessary to supply active species such as F (fluorine) radicals and O (oxygen) radicals into the dry vacuum pump 12 having deposits attached thereto through the inlet pipe 14, and includes an active species generating device 60 equipped with a plasma generating means such as a high-frequency induction coil for generating ICP (inductively coupled plasma), and an active species supplying pipe 62 for feeding the active species generated by the active species generating device 60 to the inlet pipe 14. Among these, the active species supplying pipe 62 is provided with a branch pipe 62a branched midway, and the downstream end of this branch pipe 62a is connected to the upstream end of the outlet pipe 16, so that active species can also be supplied from the outlet pipe 16 side into the dry vacuum pump 12. An opening / closing valve 64 is attached to this branch pipe 62a, and when active species are supplied to the upstream end of the outlet pipe 16, this opening / closing valve 64 is operated to be opened.

[0027] The activated species generator 60 contains Ar (argon) gas necessary for generating plasma and NF 3 and O 2 Specifically, Ar gas is supplied to the active species generator 60 via an Ar supply line 66 whose gas supply amount is controlled by a mass flow controller 66a, and NF gas whose gas supply amount is controlled by a mass flow controller 68a. 3 NF is supplied to the active species generator 60 via a supply line 68. 3 The gas supply amount is controlled by the mass flow controller 70a. 2O is supplied to the active species generator 60 via a supply line 70. 2 When Ar gas is supplied to the active species generator 60 through the Ar supply line 66, the on-off valve 66b is opened, and NF 3 NF is supplied to the active species generator 60 via a supply line 68. 3 When supplying O 2 A supply line 70 supplies O to the active species generator 60. 2 When supplying the gas, the on-off valve 70b is opened and the on-off valve 65 is closed at the same time.

[0028] In addition, when the active species supplying means 24 is provided, it is preferable to attach a differential exhaust pipe 72 that communicates with the inlet pipe 14 and the outlet pipe 16 as shown in FIG. 3. This is because, in order to generate active species in the active species generating device 60, a plasma generating means (not shown) is started to generate NF 3 Or O 2 etc. must be turned into plasma. To do this, the vacuum pump 20 must be operated to evacuate the inside of the plasma generating means, but if the inside of the dry vacuum pump 12 is almost completely clogged with deposits, it becomes impossible to evacuate. In such a case, by opening the on-off valve 74 provided in the differential exhaust pipe 72, it becomes possible to evacuate the inside of the plasma generating means by the vacuum pump 20, and the active species supplying means 24 can be operated.

[0029] The cleaning device 10 for the dry vacuum pump of this embodiment configured as above further includes the following components. First, in the case where the dry vacuum pump 12 to be regenerated and extended by the cleaning device 10 is composed of a lower main pump 12a and an upper booster pump 12b as shown in FIG. 3, if the inside of the pump is blocked when a high-temperature fluid is introduced into the pump from the inlet pipe 14 connected to the booster pump 12b side, the main pump 12a cannot be heated sufficiently. For this reason, a heating device 28 for heating the main pump 12a is provided. As the heating means of the heating device 28, a known method can be adopted, but it is particularly preferable to use induction heating (IH) which can directly heat the casing of the iron main pump 12a from the surface. The heating temperature by the heating device 28 is preferably set to 300°C or less, more preferably 250°C or less, so as not to melt the O-ring (made of fluororubber) of the pump (not shown). Depending on the structure of the pump, the booster pump may also be heated.

[0030] In addition, the dry vacuum pump cleaning device 10 of this embodiment is provided with a second fluid heating device 76, which heats the N 2 N is supplied through a branch pipe 54c branched from the supply line 54. 2 A high-temperature fluid is generated by heating N 2 In addition, CDA may also be used. The generated high-temperature fluid is supplied to the upstream end of the outlet pipe 16 via a fluid supply pipe 78. Reference numeral 54d in Fig. 3 denotes an on-off valve that is opened when the second fluid heating device 76 is used.

[0031] Furthermore, in the dry vacuum pump cleaning device 10 of this embodiment, the space within the cleaning chamber 32 covered by the hood 30 and the atmospheric exhaust line 16a are connected by a local booth exhaust pipe 80. Therefore, even if harmful exhaust gas leaks into the cleaning chamber 32 during replacement work of the dry vacuum pump 12, the leaked exhaust gas is sucked in via the local booth exhaust pipe 80, the atmospheric exhaust line 16a, the abatement device 22 and the fan 58, so it is safe.

[0032] In the dry vacuum pump cleaning device 10 of this embodiment, a preheating chamber (not shown) for preheating the dry vacuum pump 12 to be cleaned next is provided adjacent to the cleaning chamber 32. The dry vacuum pump 12 installed in the preheating chamber and waiting for the cleaning operation is also supplied with a high-temperature fluid for preheating.

[0033] The dry vacuum pump cleaning device 10 of this embodiment configured as described above has each component housed within a single cabinet 82, and this cabinet 82 is equipped with a housing exhaust pipe 84 to prevent harmful gases from accumulating inside.

[0034] Next, a method for cleaning a dry vacuum pump using the dry vacuum pump cleaning device 10 of this embodiment will be described with reference to FIGS. 1, the method for cleaning a dry vacuum pump of the present invention includes the steps of "pre-operation inspection S1", "installation of the dry vacuum pump S2", "start-up check inspection S3", and, if necessary, "regeneration process S4", "start-up check reinspection S5", "life extension process S6", "post-operation inspection S7", and "dry vacuum pump removal S8", in that order. Among these, the most important steps are "start-up check inspection S3", "regeneration process S4", and "life extension process S6".

[0035] The pre-operation inspection S1 is a process for checking whether the dry vacuum pump 12 cannot be started due to adhesion of deposits, in which the inside of the pump is visually inspected from the intake and exhaust ports to check the state of deposits, and if necessary, the deposits are sampled and chemically analyzed (qualitatively analyzed), and the rotor is manually rotated using a torque wrench. If the torque at that time is below a predetermined reference value, such as 24 N·m or less or 60 N·m or less, then "dry vacuum pump installation S2" is performed, in which the dry vacuum pump 12 is installed in the cleaning chamber 32. On the other hand, if the torque when the rotor is manually rotated using a torque wrench exceeds the predetermined reference value, it is preferable to exclude the pump from processing as being unrecoverable.

[0036] Next, the dry vacuum pump 12 installed in the cleaning chamber 32 starts logging the current value, and a "start-up confirmation test S3" is performed to check the initial startup by exhausting at atmospheric pressure, and if startup is possible, a "life extension process S6" is performed, and if startup is not possible (start-up is not possible), a "regeneration process S4" is performed. Also, if startup is possible, initial characteristics such as conductance and exhaust characteristics may be measured before the "regeneration process S4" or "life extension process S6".

[0037] The "regeneration process S4" is a process in which a high-temperature fluid is mainly introduced into the dry vacuum pump 12 to remove deposits remaining inside. As shown in FIG. 2A, "thermal regeneration with atmospheric exhaust S4.1", "thermal regeneration with vacuum exhaust S4.2" and "cycle exhaust S4.3" are carried out in this order.

[0038] Thermal regeneration with atmospheric exhaust S4.1 is a process in which a predetermined flow rate of high-temperature fluid is introduced into the dry vacuum pump 12 from the inlet pipe 14 while adjusting the pressure within a range that does not cause excessive pressurization, and exhaust gas and the like discharged from the dry vacuum pump 12 via the outlet pipe 16 is sent to the abatement device 22 via the atmospheric exhaust line 16a. After this thermal regeneration with atmospheric exhaust is performed for a predetermined time, for example 70 minutes, thermal regeneration with vacuum exhaust S4.2 is performed.

[0039] The thermal regeneration with vacuum evacuation S4.2 is a process in which a predetermined flow rate of high-temperature fluid is introduced into the dry vacuum pump 12 from the inlet pipe 14 while being adjusted within a range that does not cause excessive pressurization, and exhaust gas and the like discharged from the dry vacuum pump 12 via the outlet pipe 16 is sent to the abatement device 22 via the reduced pressure exhaust line 16b while being evacuated by the vacuum pump 20. After this thermal regeneration with vacuum evacuation is performed for a predetermined time, for example 15 minutes, cycle evacuation S4.3 is performed.

[0040] In cycle exhaust S4.3, high-temperature fluid is supplied from inlet pipe 14 while outlet valve 40 of outlet pipe 16 is closed to pressurize the inside of dry vacuum pump 12 with high-temperature fluid, and then outlet valve 40 is opened to discharge the high-temperature fluid in the dry vacuum pump 12 all at once, and the momentum of this high-temperature, high-pressure gas flow discharges the deposits inside. This series of steps is repeated a predetermined number of times, for example, 10 times, which is cycle exhaust S4.3. In cycle exhaust S4.3, exhaust gases discharged from dry vacuum pump 12 are evacuated by vacuum pump 20, and are sent to decomposition device 22 through reduced pressure exhaust line 16b.

[0041] After the dry vacuum pump 12 has completed the regeneration process S4 as described above, a "start-up confirmation re-inspection S5" is performed to check the initial startup by exhausting at atmospheric pressure, and if the regeneration is successful and startup is possible, a "life extension process S6" is performed, and if startup is not possible (start-up is not possible), the "regeneration process S4" is performed again. Note that it is preferable to set an upper limit on the number of times the regeneration process S4 is repeated when startup is not possible after the start-up confirmation re-inspection S5, taking into consideration the protection of each part of the dry vacuum pump 12 and economic efficiency.

[0042] The "life extension process S6" is a process in which a high-temperature fluid is introduced into the dry vacuum pump 12 while the dry vacuum pump 12 is mainly activated, and the above-mentioned deposits remaining inside the dry vacuum pump 12 are removed, and as shown in Fig. 2B, "starting the dry vacuum pump S6.1" and "cleaning work S6.2" are performed in this order. Of these, the starting up of the dry vacuum pump S6.1 is literally a process in which the dry vacuum pump 12 is started up.

[0043] The cleaning operation S6.2 is a process in which the above-mentioned "thermal regeneration with atmospheric exhaust S4.1" and "thermal regeneration with vacuum exhaust S4.2" are carried out continuously and integrally, in which a predetermined flow rate of high-temperature fluid is introduced into the dry vacuum pump 12 from the inlet piping 14 while being adjusted within a range that does not cause excessive pressurization, and the exhaust gas, etc. discharged from the dry vacuum pump 12 via the outlet piping 16 is first sent to the decontamination device 22 via the atmospheric exhaust line 16a, and after a predetermined processing time, such as 60 minutes, is switched to being sent to the decontamination device 22 via the reduced pressure exhaust line 16b, and is sent to the decontamination device 22 while being evacuated by the vacuum pump 20 for a predetermined time, such as 30 minutes.

[0044] Next, the dry vacuum pump 12 that has completed the life extension treatment process S6 is subjected to a "post-work inspection S7." This post-operation inspection S7 inspects the exhaust characteristics and conductance of the dry vacuum pump 12. If this inspection confirms that the performance of the dry vacuum pump 12 has been restored after the cleaning operation S6.2, the current value logging is terminated and the "dry vacuum pump is removed S8" is performed, thereby completing the method for cleaning the dry vacuum pump of this embodiment.

[0045] According to the method for cleaning a dry vacuum pump of this embodiment, either the regeneration process S4 or the life extension process S6 is selected and executed depending on whether the dry vacuum pump 12 can be started due to deposits accumulated inside, so that the deposits inside the dry vacuum pump 12 can be efficiently removed.

[0046] In the above embodiment, the case where only the high-temperature fluid is introduced into the dry vacuum pump 12 in the regeneration process S4 and the life extension process S6 has been described. However, if the deposits in the dry vacuum pump 12 cannot be removed by the high-temperature fluid alone, active species such as F radicals generated by the active species supply means 24 may be introduced into the dry vacuum pump 12 together with the high-temperature fluid or separately from the regeneration process S4 or the life extension process S6 to chemically decompose and remove the deposits.

[0047] In the above embodiment, the dry vacuum pump 12 is heated only by the high-temperature fluid. However, in the regeneration process S4, which is performed on a dry vacuum pump 12 with so much deposits stuck inside that it cannot be started, it is preferable to heat the dry vacuum pump 12 from the main pump 12a side as well using the heating device 28.

[0048] In addition, the present invention can of course be modified in various ways within the scope of what a person skilled in the art can imagine. [Explanation of symbols]

[0049] 10: Dry vacuum pump cleaning device, 12: Dry vacuum pump, 14: Inlet piping, 16: Outlet piping, 16a: Atmospheric pressure exhaust line, 16b: Reduced pressure exhaust line, 18: High temperature fluid supply means, 20: Vacuum pump, 22: Detoxification device, 24: Active species supply means, 26: Trapping device, 28: Heating device.

Claims

1. A method for cleaning a dry vacuum pump having deposits therein, comprising the steps of: A start-up check test to check whether the dry vacuum pump can be started or not. a regeneration process carried out when the dry vacuum pump cannot be started; a life extension process that is executed when the dry vacuum pump can be started or when the dry vacuum pump can be started after the regeneration process, The regeneration process is a process of introducing a high-temperature fluid into the dry vacuum pump to remove the accumulated deposits, a second cleaning step for cleaning a dry vacuum pump, the second cleaning step being a step of introducing a high-temperature fluid into the dry vacuum pump while the dry vacuum pump is in operation, and removing the deposits remaining inside the dry vacuum pump.

2. 2. The method for cleaning a dry vacuum pump according to claim 1, The method for cleaning a dry vacuum pump, characterized in that the high-temperature fluid is at least one fluid selected from the group consisting of air, nitrogen, oxygen, argon, hydrofluoric acid, and chlorine trifluoride heated to 50°C or higher and 400°C or lower.

3. 3. The method for cleaning a dry vacuum pump according to claim 1, A method for cleaning a dry vacuum pump, characterized in that in the regeneration treatment step and the life extension treatment step, active species are introduced into the interior of the dry vacuum pump in addition to the high-temperature fluid.

4. 3. The method for cleaning a dry vacuum pump according to claim 1, A method for cleaning a dry vacuum pump, comprising the steps of: varying the pressure of a high-temperature fluid when introducing the high-temperature fluid into the interior of the dry vacuum pump.

5. 3. The method for cleaning a dry vacuum pump according to claim 1, A method for cleaning a dry vacuum pump, comprising the steps of: introducing a high-temperature fluid into the interior of the dry vacuum pump; and simultaneously starting and stopping the dry vacuum pump repeatedly.

6. A cleaning device for regenerating and extending the life of a dry vacuum pump having deposits accumulated therein, comprising: an inlet pipe (14) connected to the intake port of the dry vacuum pump (12); An outlet pipe (16) connected to the exhaust port of the dry vacuum pump (12); a high-temperature fluid supply means (18) for supplying a high-temperature fluid into the dry vacuum pump (12) via the inlet pipe (14); an atmospheric pressure exhaust line (16a) and a reduced pressure exhaust line (16b) which are formed by branching off the downstream end of the outlet pipe (16) and are capable of switching the gas flow destination; a vacuum pump (20) installed in the above-mentioned reduced pressure exhaust line (16b); and A dry vacuum pump cleaning device comprising a detoxification device (22) provided downstream of the atmospheric pressure exhaust line (16a) and the reduced pressure exhaust line (16b) for detoxifying exhaust gas discharged from the dry vacuum pump (12).

7. 7. The dry vacuum pump cleaning device according to claim 6, A dry vacuum pump cleaning device further comprising an active species supplying means (24) for supplying active species into the dry vacuum pump (12) through the inlet pipe (14).

8. 8. The cleaning device for a dry vacuum pump according to claim 6, A cleaning device for a dry vacuum pump, characterized in that the outlet pipe (16) is provided with a trap device (26) for trapping components other than the gas discharged from the inside of the dry vacuum pump (12).

9. 8. The cleaning device for a dry vacuum pump according to claim 6, The dry vacuum pump cleaning device further comprises a heating device (28) for heating the dry vacuum pump (12) from the outside.

10. 10. The dry vacuum pump cleaning device according to claim 9, A cleaning device for a dry vacuum pump, characterized in that the heating means of the heating device (28) is induction heating.

11. 8. The cleaning device for a dry vacuum pump according to claim 6, A dry vacuum pump cleaning device further comprising a preheating chamber for preheating the dry vacuum pump (12) which is to undergo a subsequent cleaning operation.

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