Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1~3~826
Background of ~he Invention
This invention relates to a dredging vessel, provided with a ladder
to extend a dredge to be moved along a track.
A dredging vessel of that type can extend its dredge consisting of a
rotary cutter ~r an excavator wheel to which a suction tube is connected,
down to a depth of 30 meters, but often dredging operations in deeper
water are to b~ performed.
; ~:
Summary of the Invention
~he present in~-ention has as its object to fulfil this requirement and
achieves this cue to the aspect that the dredging vessel so as to be
- adapted to be used as well on a track on a deep bottom is constructed of
- an upper body ~nd a lower body which supports the ladder, and when emptied ~-
' floats up to below the upper body, and when ballasted sin~s down so as to
extend the ladc`er down to the deep bottom. This sinking down is made
possible by a ~ivot joint between the upper and lower bodies in the fore- ;
ship and a hancer tackle therebetween in the aftship, with the further
aspect that the upper body is arranged as an engine pontoon and carries
the upper mud line system whereas the lower body carries the lower mud
line system, s~;d two line systems being adapted to be coupled at the
pivot joint between the upper and lower bodies.
It will thus be possible to dredge down to a depth of 100 meters-
'
On the deeply ~ bmerged parts of the lower body a high pressure from all
i~ ~
' ' : ! : , :
~3~8Z6
s~de~ wlll he exert~d and thia pres6ure can be taken a~ the lower body
consistq of a pontoon, having ln it~ deeply submerslble paxts a pres~ure-
reslstant citadel, and the lower body can take the lncreaslng pres~ure at
gr~ater depths as the cyllndrlcal pres~ure hull deflning the cltadel consl~t~
oP sectlon~ deflned by transver~e ~ulkhead~, the dlameter o~ whlch 18
reduced tow~rds more deeply sub~erslble pArts, ~o that wlth equal thlckne~
- of the pressure hull it~ pressure a~rength at greater depths gradually
lncreases.
The hereln disclo3ed d~epsea suction cutter dredger 13 further characterized
ln that the forepart of the lowor body when thl~ lower body sinks down
plvots up to above the water and gives acce~s to the lower kody, and in that
ln the rear part of the lcwer body a quick d~n~t~nk to be emptled and
ballasted ls arranged. There can be a constant balance between the b~oyancy
of the pres~ure-resl~tant core and the welght of the - for the remalnder
flooded - pontoon, of which the lower body conslsts, and sinklng down, and
flo-tlng up, respectlvely, 1~ controlled by the small qulck divlng tank in
the rear~hip o~ sald lowar pontoon, ~ald tank only having to provide a small
~orce to exert a momantladapted for floating up or sink ng down,about the
pivot ~oint between the upper and lower bodie~ in the foreship. A posltive
wlre force ln the hanger tackle is thereby retalned, however, as the
hol~tlng welght of the lower body ln the hanger tackle r~malns larger than
; lts buoyancy,
An alternative embcdi~ant 18 such that the boaie3 form a nesting ~h~le a6
ths lower body 1B adapted to be recelved in a fo~e and aft well ln the
upper body, ana a sound construction of the lower body 18 ochlev~d as tho
lower bcdy has a ~upportlng outer hull aroun~ the cylindrical pressur~ hull,
wlth the 8paCQ provlded between the outer hull and the pres~ure hUll bslng
flooded, and pre~erably the outer hull con~lst~ of a ~ubstantially open
truss atructure. The lower body thu8 forms a quite sturdy, but nevertheless
llght support whlch carrles as a core the prassure-resi~tant cylinder with
pumps and lLnes.
.' , .
:
- 113~3Zti
In the two herein di~closed ~mbodlment~ 1~ further provlded th~t the
1addQX 1B to be brought above the water n8 the low~r body plvotally
~upport~ the ladder.
The lnvention 15 de~crlbed ln re det~ll herelnaft0r ln vlew of the
dr~wlng~ showing lllustr~ti~e embodlments thoxeo~.
Brle$ Des~rlptlon o~ the Drawlngs
Flgure 1 18 a longitudinal view of the entlre dredging ves~el ln floatlng
condltion, with tho lower body ~loatad up to below th~ upper ~ody and
belnq ~ecured thereto7
flgure 2 1~ a planview of ~he dre~ging ve~al of flgure 1;
flgure 3 show~ the dredging ves~el of figures 1 and 2 in longltudlnal
vlew when the lower body slnks aown~
fleure 4 ~hows tho ~unken down con~ltion wlth the dxedglng lmplement
~xtended do~n to th~ deep ~ottom~ and
flguro 5 ~hows another embodlment of the dkedglng ve~el ln longltudinal
vl-w, wlth ~he lower body belng ~dapted to be pivot~d into and out of a
~oro and a~t well ln the upper body.
D-~crlptlon of the Pr~ferred Embodlments
ThQ dredgl~g vessel 1 as r~pre~ented in the drawings ln a deep~ea ~uction
cutter dredg~r which he~laes at the usual dxedglng depth~ up to 30 met~rs
can al~o reach wlth lt~ dredging impl~ment 3 w~lch 1Y supported ~y the
ladder 2 ana con~lsts of a cutter or ~xGa~ator wheel down to the bottom 4
ln waSer with a depth of even up to 100 mater&.
To that end the dredging ves~el 1~ constructed o~ an upper body 5 and a
lo~ex body 6, whlch has in the foreship a plvot ~oint 7 with the upper
113~82~;
body 5. In the rear part of the lower body 6, which part 18 movable
about the plvot Joint 7 ln a hanger tackle 8 ~rom the winch 9, ~ drivlng
tank 10 is arrangcd. By ballAstln~ ~aid tank 10 the lowQr body 6 cantlng
on the pivot ~o~nt 7 ln deeper wat~r with lts rear part whlch carrlee the
ladder 2, can be suhmerged wlth the dredging implement 3 whlch it suppoxts,
down to the bottom 4 to carry out dredglng operatlon~ there.
By emptying th~ tank 10 and haullng the t~ckle 8 wlth the winch 9 the
lower body 6 can fl~at up agaln up to below the upper body 5 and can be
integrally connected th~rewlth for dredglng operation~ in shellow water.
Flgure~ 1-4 show an embodim~nt ln whlch the lower body 6 forms the o~t~r
hull part and the upper body 5 form~ ~he lnner hull part to be r~c~lved
and se~ured therein. Flgur~ S ~how~ the rever~e sltuatlon that the lower
body 6 i~ adapted to be recQlved and secured wlthin the upper bcdy 5 ln
a fore and aft well 11 thereln.
The upper body 18 preferably arranged as an englne pontoon, wlth an englna
room 12, and carrled the surface lines 13 of the mud llne system, of whlch
the ~ubmerged llne ~eCt~n 14, wlth the pertalning pu~p~, to wlt
suctlon pu~p lS, the ~uotlon llne 16 o~ whlch act~ on the dredglng
lmplement 3, and a rlser pump 18 which ls ln~tallod ln the pre~sure line 17
of the pump 15 to pre~s the mud ~urther aw~y, is situated in the lower body
6. The two llno ~ectlon~ 13 and 14 ara to be mutually coupled at the
plvot ~oin~ 7.
~n osder to be able ~o wlth~tand the water pressure from all ~ideæ at
greater dRptha th~ lower body 6, ~9 ~ho~n with dotted lines ln i~ure 3
and also ln flgure 5, i~ prov~d~d wlth a preæsuro-re~i3tant cltadel or
core 19, the pr2~sura str0ngth o~ which at greater ~ubmerged depths ~hould
gradually al80 be hlgher. The citadel 19 cGnsl~ts of a cyl~ndrlcal pressure
hull which 18 relnforcea by ~he ~rames a~d ~lkhead~ 20. Th~ dlameter of
the cyllnder 19 18 gradually reduced towardæ deeper water, l.e. towards
-4-
~13~ 6
the rearship of the lower body 6, ~o a~ to be able to wlthstand higher
pres~ures, and has,as illu~trated, at e~ch of the tranaverae bulkhea~ 20
a stepwi~e adaptation 21.
The body space wlthin th~ cyl~nder 19 form~ a walk-bl~ pa38age from ~ore
to aft and i8 acce~slble ~rom the forepart 22 of the low~r ~ody 6 ahead
of the pivot ~oint 7, whlah part, when the lower body i5 sunken down,
pivot~ up. The body ~pace 23 out~lde the cylinder 19 $8 flooded by water
from tha outslde. ~he lower body 6 may have a close~ outer hull 24 whlch,
as ~h~ kody space 23 ls ~loo~cd, need not be adapted ~o water pras~ure
from all side~, but the lowe~ body 6 may a~ well foxm an open tru~s cage
25 whlch ~upports th~ pres~ure oyllnder 19 pre~orably at ~he ~ransv~r~e
bulkhead~ 20.
The hydraullco of th~ 3ubmer~1bl~ lower body 6 ara prearably 80 that the
welght thereo~ ls substantlally in balance wlth the buoyancy provlded by
lt~ pre~nure-reslstant core 19, ~o that by ballastlng and emptying the
pre~ tanlc lO ~nd~or b~ operating th0 winch 9, the lower body 6 can l:e
c-u8ed to qulckly ~ink down~ and float up, re~pectlvely.
:
In order to be able to brlng tho laddar above the water it 1~ vertl~ally
plvotally connact~d to the lower body. ~here should, however, ln vlew of
the due to the ~teep ~lope at which the ladder ls ~tandlng when dredging
t great depths, con-~aerabl~ longltudlnal coqnponent of the force
exerted on the dredglng ln~plement when ~redging, a po~ltion ~lxatlon of
the plvotal ladder be pre~ent, whlch ls not further represented in the
dra~ing~.
