Abstract:
A method for performing maintenance on a chromatography column ( 1; 41 ) comprising the steps of: 
     a) when maintenance is required, detaching a detachable joint ( 7; 63 ) between a bottom plate ( 5; 53 ) of the chromatography column and a stand ( 3; 43 ) on which the chromatography column is provided;
 
b) attaching an adaptor ( 15; 59 ) provided in the chromatography system to any part of the chromatography column ( 1; 41 ) making it possible to lift the bottom plate ( 5; 53 ) from the stand ( 3; 43 ) with the adaptor ( 15; 59 ); and
 
c) raising the adaptor ( 15; 59 ) and thereby also the bottom plate ( 5; 53 ) such that maintenance can be performed under the bottom plate ( 5; 53 ).

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention relates to a method for performing maintenance on a chromatography column and to a chromatography system. 
       BACKGROUND OF THE INVENTION 
       [0002]    Some parts of a chromatography column need to be cleaned or replaced regularly. For example access is needed beneath a bottom plate of the chromatography column to change a valve provided there. Usually there is not much space between the bottom plate and the floor because it is preferable to keep the overall height of the chromatography column as small as possible. Because of the limited space below the bottom plate it is tricky to get access to the bolts and valves that need to be accessed. 
       SUMMARY 
       [0003]    An object of the present invention is to solve the problems described above related to prior art. 
         [0004]    This is achieved in a method according to claim  1  and in a chromatography system according to claim  4 . 
         [0005]    Hereby an operator will get good access to the underside of the bottom plate and at the same time the overall height of the chromatography column can be kept at a minimum. 
         [0006]    Suitable embodiments are described in the dependent claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIGS. 1   a - 1   c  show schematically a chromatography system according to one embodiment of the invention in three different positions. 
           [0008]      FIG. 2  shows schematically one example of a nut securing the bottom plate to the stand. 
           [0009]      FIG. 3  is a flow chart of a method according to one embodiment of the invention that can be performed on the chromatography system of  FIGS. 1   a - 1   c.    
           [0010]      FIGS. 4   a - 4   d  show schematically a chromatography system according to another embodiment of the invention in different positions of a method according to one embodiment of the invention. 
           [0011]      FIG. 5  is a flow chart of a method according to one embodiment of the invention that can be performed on the chromatography system shown in the  FIGS. 3   a - 3   d.    
           [0012]      FIG. 6  shows schematically a chromatography system according to another embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0013]      FIG. 1   a  shows schematically a chromatography system according to one embodiment of the invention. All the parts are not mentioned here but they are conventional parts of a chromatography system. A chromatography column  1  is provided on a stand  3 . According to the invention a bottom plate  5  of the chromatography column is detachably secured with a detachable joint  7  to the stand  3 . In this embodiment the detachable joint  7  is shown as two bolts  7  securing the bottom plate  5  to the stand  3 . One example of a detachable joint is shown in more detail in  FIG. 1   d . The chromatography column  1  comprises further a column tube  9 , connected at its bottom end to a bottom flange  11 , a distributor  13  and the bottom plate  5 . The column tube  9  is connected at its upper end to an upper flange  14 . Furthermore an adaptor  15  is provided in the chromatography system. According to the invention the adaptor  15  can be secured to the chromatography column  1  by a locking means  16 . The adaptor  15  comprises an adaptor rod  17 , a worm gear  19 , an adaptor backing plate  21  and an adaptor stop  23 . The adaptor stop  23  is provided in order to secure that the adaptor backing plate  21  will not be lifted above the column tube  9 . In this embodiment of the invention a locking means  16  is provided to the upper flange  14  and is adapted to engage with the adaptor stop  23  when the adaptor  15  is raised such that the whole column can be raised from the stand when the detachable joint  7  has been released. In an alternative embodiment where no adaptor stop  23  is provided the locking means  16  can instead be arranged to engage directly with the adaptor backing plate  21  when the adaptor  15  is raised when maintenance beneath the column is needed. The locking means  16  is detachable and will be removed when the adaptor needs to be lowered inside the column tube  9 . The design of the locking means  16  can of course vary. Furthermore a lid  27  and a lid support  29  are provided above the column tube  9  and upper flange  14  and connected to the stand  3  in order to support the chromatography system structure and aid maintenance This is according to conventional models of chromatography systems. 
         [0014]    In  FIG. 1   b  the chromatography system of  FIG. 1   a  is shown schematically in a second position where the lid  27  and lid support  29  have been lifted up to a second position. The bolt  7  (detachable joint) securing the bottom plate  5  to the stand  3  is also released now. 
         [0015]    In  FIG. 1   c  the chromatography system of  FIG. 1   a  is shown schematically in a third position where the adaptor  15  is raised. Because of the locking means  16  securing the adaptor stop  23  and thus the adaptor backing plate  21  to the upper flange  14  of the chromatography column  1  and because the detachable joint  7  between the bottom plate  5  and the stand  3  has been released the chromatography column  1  will be raised above the stand  3  together with the adaptor  15 . Hereby there will be a space below the bottom plate which can be used when access is needed to the underside of the chromatography column  1  for performing maintenance of the system. 
         [0016]    Furthermore a lock sprint  22  is possibly provided in order to secure the adaptor and the chromatography column in the raised position. 
         [0017]      FIG. 2  shows schematically in more detail the detachable joint  7  according to one embodiment of the invention. The bottom plate  5  and the stand  3  are shown partly in this view. The detachable joint  7  comprises a bolt  31 , a lock nut  33  and a nut  35 . The detachable joint  7  can of course be deigned differently. 
         [0018]      FIG. 3  is a flow chart of a method according to one embodiment of the invention that can be performed on the system shown in  FIGS. 1   a - 1   c . The method steps are described in order below: 
         [0019]    S 1 : Lifting the lid  27  and lid support  29  to a first position. 
         [0020]    S 3 : Detaching the detachable joint  7  between the bottom plate  5  and the stand  3 . 
         [0021]    S 5 : Securing the adaptor  15  to the chromatography column, here the upper flange  14  of the chromatography column (if not already done). 
         [0022]    S 7 : Lifting the adaptor  15  together with the rest of the chromatography column  1 . 
         [0023]    S 8 : Possibly providing a lock sprint for securing the adaptor  15  and the chromatography column  1  in the raised position. 
         [0024]    S 9 : Performing maintenance beneath the bottom plate  5 . 
         [0025]      FIGS. 4   a - 4   d  show schematically a chromatography system according to another embodiment of the invention in different positions of a method according to one embodiment of the invention. In  FIGS. 4   a - 4   d  the chromatography system comprises a chromatography column  41  on a stand  43  with a swing out feature, i.e. a column tube  45  together with an upper flange  47  and a bottom flange  49  can be separated from an upper lid  51  and a bottom plate  53  and then rotated out from these parts. The bottom plate  53  comprises here also a distributor  54 . The column tube  45  is all time supported by the stand  43 . 
         [0026]      FIG. 5  is a flow chart of a method according to one embodiment of the invention that can be performed on the chromatography system shown in the  FIGS. 4   a - 4   d.  The method steps are described in order below and with reference to the corresponding  FIGS. 4   a - 4   d.    
         [0027]    S 31 : The column tube  45  is released from the upper lid  51  and the bottom plate  53 . 
         [0028]    S 33 : The column tube  45  is rotated out from the upper lid  51  and the bottom plate  53 . This is shown in  FIG. 4   b.    
         [0029]    S 35 : An adaptor  59  of the chromatography column  41  is lowered almost all the way down to the distributor  54  and the bottom plate  53 . This is shown in  FIG. 4   c.    
         [0030]    S 37 : The adaptor  59  is locked to the bottom plate  53  by a locking means  61 . This is shown in  FIG. 4   c . The locking means  61  can be designed in different ways. In this shown embodiment one part of the locking means is attached to the adaptor by a bolt and another part of the locking means is attached to the bottom plate by another bolt. 
         [0031]    S 39 : A detachable joint  63  between the bottom plate  53  and the stand  43  is released. 
         [0032]    S 41 : The adaptor  59  is lifted together with the bottom plate  53 , suitably to a height that is sufficient for a person to sit beside it and conveniently perform the maintenance required, such as unbolting and changing valves on the underside of the chromatography column  41 . This is shown in  FIG. 4   d.    
         [0033]    S 43 : Possibly a lock sprint  65  (shown in  FIG. 4   d ) is provided to lock the adaptor  59  and the bottom plate  53  in the raised position. 
         [0034]    S 44 : Performing maintenance beneath the bottom plate of the column. 
         [0035]    One advantage with the invention is that access to the bottom side of the bottom plate is provided without increasing the total height of the chromatography system. 
         [0036]      FIG. 6  shows schematically a chromatography system according to another embodiment of the invention. Most of the parts here are the same as the parts described in  FIGS. 1   a - 1   c  and these parts will not be mentioned here. The difference in this embodiment is the design of the locking means  16 ′. In this embodiment an adaptor stop  23 ′ is designed similar to the design of the adaptor stop  23  in  FIGS. 1   a - 1   c . The adaptor stop  23 ′ is arranged to engage with a locking means  16 ′ that is secured to the chromatography column  1 ′ when the adaptor  15 ′ is moving upwards when maintenance below the chromatography column is needed. Alternately the locking means  16 ′ could be arranged to engage directly with the adapter in a construction without adapter stop. For lifting the column with the adapter during maintenance a detachable joint  7 ′ needs also to be detached as described in relation to  FIGS. 1   a - 1   c . The locking means  16 ′is a detachable part.