Overcoming High Static Heads for Mechanical Pumps on Platforms
of 2
Transcript of Overcoming High Static Heads for Mechanical Pumps on Platforms
-
8/20/2019 Overcoming High Static Heads for Mechanical Pumps on Platforms
1/2
Division SJet EjectorsVacuum Technology
Badenstedter Straße 56D-30453 HannoverP. O. Box 91 13 63D-30433 Hannover
Phone:Fax:Internet:E-Mail:
+49 511 2129-0+49 511 2129-223http://[email protected] 1
3 2 - P l a t f o r m s - K p - K r f - 1 8 . 0
1 . 2 0 1 2
Relative suctionflow of water jetwater ejectors(pDA < 50 mbar max.)
Figure 4
Your personal hotline: [email protected]
Of course, in both casessuch an arrangement meansthat the mechanical pump on
board must be designed in
The corresponding volumeratios may be taken from thefollowing diagram in Figure 4.
such a manner that its deliv-ery flow is increased by theportion of the motive flow for
the ejector. Overcoming high static heads formechanical pumps on platforms
-
8/20/2019 Overcoming High Static Heads for Mechanical Pumps on Platforms
2/2
Particularly where drill plat-forms are concerned it maybe that this physically possi-
ble static head must be ex-ceeded considerably. A fur-ther pump has to be pre-connected to the existing
supply pumps for seawateron the platform which deliv-ers to the main pump and so
ensures its operational relia-bility.
About pump systems it isgenerally known that theirstatic heads are limited due
to prevailing physical influ-ences. The limiting value isto be found frequently at astatic height of approx. 8 mwater column.
The advantages of ejectortechnology exist in the factthat here it is a case of apure flow apparatus withoutany moving mechanical ele-ments and which thereforeworks practically wear-freeand which so represents anelement of the suction pipe-
line for the mechanical pumpon board.
A further advantage may beseen in the fact that theseejectors manage without anelectrical power supply andcontrol elements. This simpli-fies installation quite consid-erably and contributes to agreat extent towards the op-erational reliability of the
whole system. Two switch-ing possibilities are principal-ly conceivable.
On principle there are two different systems
which offer themselves for this case:
► A pre-stage executed as a mechanical
pump with electrical drive
► A pre-stage executed as a jet ejector
Figure 1
For the first version water issupplied from the pressureside of the mechanical pump
on board directly to the ejec-tor located in the suctionpipeline and serves as itsdrive agent. A symbolic rep-resentation hereof may betaken from Figure 2.
In the case of this arrange-ment a direct supplying ofthe after-connected plantsystems on the platformtakes place.
Figure 2
Figure 3
The second variant workswith a so-called air vessel.
A symbolic representationof this may be taken fromFigure 3.
The advantage of this sys-tem switching is that a cer-tain puffer effect is achieved
via the air vessel and that acontinuous operation mode,as circumstances require, isnot necessary. This can beof advantage for the me-chanical pump on board.
