Expe imen al in es iga ion o he check al e beha iou when he flow is
e e sing
D. Him a,V.Hab
´
an, M. Hudec, and V. Pa l´
ık
B no Uni e si y o Technology, Facul y o Mechanical Enginee ing, Ene gy Ins i u e, Vic o Kaplan Depa men o Fluid
Enginee ing, Technick´
a 2, 616 69, B no, Czech Republic
Abs ac . Check al e in a pipeline is supposed o p e en he e e se flow and o allow he flow in he posi i e
di ec ion. The cons uc ion o check al es ollows hese equi emen s, bu he check al e mus no cause
p essu e pulsa ions in ansien s. I means when he fluid is accele a ing o decele a ing. The a icle desc ibes
an expe imen al in es iga ion o a swing check al e when he flow is changing i s di ec ion. The check al e
was placed in an expe imen al ci cui , whe e he p essu e on he ups eam and downs eam side o he al e
was measu ed and he cu en alue o flow a e was de e mined. The goal was o simula e condi ions in he eal
sys em, whe e he check al e slam had been obse ed.
1 In oduc ion
The check al e is an impo an pa o hyd aulic sys ems
and allows flow in one di ec ion and p e en he e e se
flow h ough he pump. The check al e can be also in-
s alled in he sys em o limi he p essu e su ge induced by
he pump ailu e [1]. The basic equi emen s on he check
al e a e:
– he low p essu e loss in he posi i e di ec ion,
–no flow in he opposi e di ec ion, i means good sealing
when he al e is closed.
P oduce s, usually, gi e s a ic cha ac e is ics o check
al es such as a p essu e d op dependence and opening de-
pendence on he flow a e, he c acking p essu e ( he p es-
su e when he check al e s a s opening) and he minimal
flow a e when he check al e is ully open.
The p oduce also can say whe he he al e is app o-
p ia e o he pulsa ing flow, sludge wa e , ho izon al o
e ical pipe and so on. These pa ame e s oge he wi h
he eliabili y and main enance difficul y allow choosing
he igh check al e o educe ope a ional cos s.
Bu , he e is a p oblem wi h p edic ing he dynamic
beha iou o he check al e in he pa icula sys em. I
is, maybe, mo e impo an han p ope ies w i en abo e.
When he fluid flow changes i s o ien a ion, he check al e
is desi ed o close be o e he back flow eloci y becomes
oo high o he wise he check al e disc slams and makes
he high p essu e su ge, which is o en connec ed wi h he
column sepa a ion pa icula ly on he ups eam side o he
check al e. The lowe s a ic p essu e in he pipeline he
g ea e column sepa a ion p obabili y. The slam can lead o
se e e damages o he check al e and/o he whole sys em
[2], [3], [4].
The check al e also can make p oblems wi h sel -
exci ed p essu e pulsa ions: The oscilla ing con ol al e
a he downs eam end o pipe causes oubles wi h check
ae-mail: [email p o ec ed]
al e slam a he ups eam end [5]. An example o he p es-
su e su ge due o he check al e slam a e he pump s op-
page is shown in he figu es 1 and 2. The slam also causes
s ong mechanical ib a ions o pipeline wi h accele a ion
abou 20 G in his case [4].
McElhaney made an ex ensi e analysis o check al e
ailu es in he nuclea indus y, because hese ailu es a e
well desc ibed, and hey ocused on co ela ion be ween
he al e design and ailu e mode and ailu e dis ibu ion [6].
Time
[
s
]
012345
-1
0
1
2
3
4
5
P essu e/Ope a ing p essu e [-]
Downs eam side
Ups eam side
Fig. 1. P essu e su ge a he check al e due o slam [4]
3.5 3.7 3.9 4.1 4.3 4.5
Time
[
s
]
-1
0
1
2
3
4
5
P essu e/Ope a ing p essu e [-]
Downs eam side
Ups eam side
Fig. 2. P essu e su ge a he check al e due o slam – de ail [4]
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
© The Au ho s, published by EDP Sciences. This is an open access a icle dis ibu ed unde he e ms o he C ea i e
Commons A ibu ion
License 4.0 (h p://c ea i ecommons.o g/licenses/by/4.0/).
In se e e pumping applica ions, almos all basic check
al es will slam, and in ex emely mild applica ions, ha dly
any check al es will slam [7]. Bu i is difficul o p edic
p obabili y o he check al e slam be ween hese wo ex-
emes.
The calcula ion o he sys em decele a ion is impo an
o say whe he he check al e will slam o no . The decel-
e a ion is calcula ed om he o iginal o wa d flow eloc-
i y and ime pe iod when he eloci y eaches ze o. I de-
pends on many ac o s: complexi y o he sys em, ic ion,
pump ine ia, s a ic head and so on. Thus, he decele a ion
can be ha dly de e mined wi hou di ec measu emen o
a leas a nume ical simula ion o he flow in he pipe line
sys em.
The maximal eloci y o he e e se flow depends on
he check al e cons uc ion and on he sys em decele -
a ion. The highe decele a ion he highe e e se eloci y
can de elop be o e he check al e closes. Then, he p es-
su e su ge ollows he Joukowski equa ion.
The e e se eloci y dependence on he flow decele a-
ion acco ding o [8] is shown in he figu e 3 and a depen-
dence published in [9] is plo ed in he figu e 4.
0 1.0 1.5 2.0
Decele a ion
[
m/s
]
0
0.2
0.4
0.6
0.8
1
.
0
Re e se eloci y [m/s]
0.5
2
Swing check
Bi old
Til ed disc
Fig. 3. Re e sal eloci y o diffe en cons uc ions o he check
al e by [8]
01015
Decele a ion
[
m/s
]
0
0.1
0.2
0.3
0.4
0
.5
Re e se eloci y [m/s]
5
2
Swing
check
Til ed disc
check
Dual disc
check
Ball
check
Swing lex
check
Silen
check
Nozzle
check
Fig. 4. Re e sal eloci y o diffe en cons uc ions o he check
al e by [9]
One can see ha esul s (e. g. o he il ed disc check
al e) a e qui e diffe en so i is ob ious ha he e e -
sal eloci y does no depends only on he decele a ion and
ype o he check al e, bu , p obably, also on he specific
cons uc ion, size, mass, placemen ,. . . The sys em decele -
a ion gi es jus a basic hin whe he he check al e ends
o slam o no .
Table 1. S and specifica ions
En y Value Uni
Pipe diame e 0.1 m
Maximal flow a e 31 l s−1
Maximal flow eloci y 3.95 m s−1
Leng h o discha ge pipe 17.3 m
S a ic head 7.5 m
Volume o bo om ank 1 m3
Volume o op ank 0.8 m3
Pipe ma e ial s eel
Maximal pump speed 1450 pm
2 Expe imen
An expe imen al s and has been buil and se es o he
examina ion o he check al e beha iou , when he flow
o ien a ion is changing. The expe imen is a pa o co-
ope a ion wi h MSA company, a p oduce o al es, and
he goal is o design a check al e, which does no slam
in ex eme ope a ing condi ions. MSA company p o ided
a swing check al e DN 100, which ends o slam and i is
he fi s check al e o a ow, which is going o be es ed.
The s and consis s o he pump, which collec s wa e
om he bo om ank. The es ed check al e is placed in
he ho izon al pa o he discha ge pipe 2.3 m abo e he
wa e le el in he bo om ank. The discha ge pipe ends in
he op ank. The wa e om op ank e u ns back h ough
he e u ning pipe and he o e spill pipe (see figu e 5 and
able 1).
P essu e senso s ( ange 0 – 1 MPa, unce ain y 0.25%
o he ange, sampling equency 1 kHz) a e placed 0.3 m,
1.4 m and 2.5 m be o e he check al e and 0.41 m, 1.4 m
and 2.38 m behind he check al e in he s eady flow di-
ec ion. The flow a e is measu ed wi h he elec omagne ic
flowme e (0 – 80 l/s, unce ain y 0.5% o measu ed alue).
One accele ome e (-50 G – 50 G, unce ain y 1% o mea-
su ed alue, sampling equency 1 kHz) is placed on he
check al e body and ano he one is placed on he pump.
Accele ome e s should help o iden i y an exac ime o
some e en s a e pump disconnec ion. The pump speed is
measu ed wi h he lase and one ma k on he mo o sha .
The pump speed is con olled wi h a equency con-
e e o con ol he flow a e and flow decele a ion. Un-
o una ely, he e was a p oblem wi h he con e e du ing
he expe imen s and i was no possible o con ol he de-
cele a ion a e.
The check al e design does no allow measu ing po-
si ion o he disc, bu check al es, which a e going o ol-
low, ha e windows o see he exac posi ion o he disc and
allow PIV measu emen o he flow field in he check al e
body.
Th ee p essu e senso s on bo h sides o he al e allow
calcula ing he wa e speed and flow a e du ing decele a-
ion by ime-p essu e me hod. Using he flowme e is no
possible due o i s g ea in eg a ion cons an so he flowme-
e can measu e jus he s eady flow a e.
The expe imen p ocedu e is ollowing:
1. S a o pump and un wi h he specific speed o ha e
a desi ed flow a e ( om 10 l/s o30l/s). I was no pos-
sible o keep he flow o ime longe han 30 s, because
he o e spill ae a ed wa e . The ai dec eases he wa e
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
2
p
Q
p
46
O e spi
ll
Discha ge pipe
Re u ning pipe
O e spill pipe
7.5 m
7.5 m
DN 100
DN 100
DN 100
p
1p
2p
3p
5
2.3 m
Fig. 5. Expe imen al s and
speed, which di ec ly influences he heigh o p essu e
peaks acco ding o Joukowski equa ion, and changes
he sys em esponse [10], [11].
2. As soon as he s eady flow was eached he pump was
disconnec ed. Since he pipe line is qui e sho , i was
possible o u n off he pump a e fi e seconds a e
he s a .
3. The measu emen was eco ded om he s a o pump
un il all ansien s a e he pump s op we e finished.
Then, i is possible o e alua e: c acking p essu e, flow
decele a ion, maximal back flow eloci y, p essu e su ge
in on o and behind he check al e, wa e speed and
accele a ion connec ed wi h mechanical ib a ion on
he check al e body.
3 Resul s
The pump was s opped om he ou diffe en s eady flow
a es: 10 l/s, 15 l/s, 20 l/s, 27 l/s and 30 l/s. An example o
esul s o s op om 15 l/s is shown in he figu es 6 o 12.
The ins an pump speed is e alua ed om scanning he
spo on he mo o sha . I allows iden i ying he ime o
pump disconnec ion om he g id and he ime, when he
sha defini ely s opped. These poin s a e, espec i ely, la-
belled wi h numbe s 1 and 6 in he figu es.
Since he e was only one ma k on he o o sha , he e
is no p oblem o coun numbe o e olu ions and calcu-
la e he exac speed ( he e is no any demand on he exac
posi ion o he ma k), bu (because we a e alking abou an
uns eady o a ion) he slowe sha o a es he less accu a e
e alua ed speed is. Tha is he eason why he las e alu-
a ed speed o he sha is 85 pm. The las ma k was ead
a he ime 3.2 s, he sha s opped a e ha .
P essu e ups eam o he check al e (figu e 7) ex-
hibi s he pump disconnec ion (poin 1), when he p essu e
s a ed dec easing. Time, when he flow changes o ien a-
ion and s a s flowing backwa d, is ma ked wi h poin 2.
This e y weak peak can be easily o e looked.
Poin 3 labels ime ins an , when he check al e s a s
closing and poin 4 is he momen , when he disc hi s he
012345
0
200
400
600
800
1000
Time
[
s
]
S
peed [ pm]
1
2
4
6
3
5
Fig. 6. Pump decele a ion om s eady flow a e 15 l/s
sea . (The column sepa a ion occu ed he e in cases wi h
g ea e ini ial flow a e).
Then, he highes peak eme ges and p essu e pulsa ions
a e damped, bu he pump sha s ill o a es. The sha s op
(poin 6) caused amplifica ion o he ollowing pulsa ions
abou 100%, bu he absolu e alue was s ill low, hus i did
no cause any significan e en . These amplified pulsa ions
we e damped wi hin 1 second.
0 1 2 3 4 5
0
50
100
150
200
2
5
0
Time
[
s
]
P
essu e
[kP
a
]
1
3
2
6
4
5
Fig. 7. P essu e in on o he check al e du ing he ansien
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
3
The p essu e downs eam o he check al e (figu e 8)
allows iden i ying he ime when he pump was discon-
nec ed (poin 1). Poin s 3 and 4 ma k momen when he
disc s a ed and finished closing.
The ollowing p essu e d op goes o he alue, which
is lowe han one would expec (poin 5). The same poin
in he figu e 7 shows ha he p essu e peak is lowe han
i should be, when he p e ious and subsequen peaks a e
conside ed. This is he ime ins an when he disc eopens
(p essu e a he ups eam side o he disc is g ea e han
a he downs eam side) and closes again. The figu e 9
0 1 2 3 4 5
80
100
120
140
160
180
200
220
2
4
0
Time
[
s
]
P
essu e
[kP
a
]
1
2
4
6
35
Fig. 8. P essu e behind he check al e du ing he ansien
shows he p essu e diffe ence on he check al e. A posi-
i e alue co esponds o he si ua ion, when he p essu e
downs eam o he al e is g ea e han ups eam o he
al e, so he check al e is closed. Nega i e alue a he
poin 5 suppo s he s a emen ha he disc eopens a ha
momen .
0 1 2 3 4 5
50
0
50
100
150
200
Time
[
s
]
P essu e di e ence [kPa]
1
2
46
3
5
Fig. 9. P essu e diffe ence on he check al e du ing he ansien
The flow a e was e alua ed om he p essu e eco ds
p4and p6by he ime-p essu e me hod:
Q( +Δ )=Δ S
Lρp4−p5−RQ2( )+Q( ),(1)
whe e he esis ance Ris no a unc ion o he ime, bu
depends on he ini ial flow a e (2), which is subjec o he
nume ical op imiza ion.
R=p4(0)−p5(0)
Q2(0).(2)
The dependence o he eloci y on he ime (figu e 10)
is compu ed om (1) by an app op ia e nume ical me hod,
when he flow a e a he las ime ins an equals ze o. The
solu ion also includes he ini ial flow a e and esis ance.
Then, he s a o decele a ion (poin 1) can be easily ound
as well as he ime, when he flow changed i s o ien a ion
(poin 2). The maximal backwa d eloci y (poin 4) is he
las in o ma ion ob ained om his g aph.
0 1 2 3 4 5
0
0.5
1
1.5
2
Time
[
s
]
Flow eloci y [m/s]
1
24
6
3
5
Fig. 10. Flow eloci y du ing he ansien
The measu emen o he accele a ion on he pump body
also gi es some in o ma ion abou e en s in he pipeline
(see figu e 11). The pump disconnec ion is no isible he e
( he e is no any change o he signal a poin 1), because all
mo ing pa s kep hei mo ing. The fi s change is ob i-
ous when he speed dec eases abou 50%. The accele a ion
ampli ude becomes no iceably lowe 0.3 s a e he pump
disconnec ion.
Closu e o he check al e disc is well isible (poin 4)
as well as i s second closu e a e eopening (poin 5). The
pump sha s op (poin 6) is be e ecognizable han pump
disconnec ion.
012345
0.4
0.2
0
0.2
0.4
0
.
6
Time
[
s
]
Accele a ion [
G
]
1
2
4
6
3
5
Fig. 11. Measu emen o he accele a ion on he pump body
The signal om he accele ome e on he check al e
body (figu e 12) con ains s ong noise so e en he iden i-
fica ion o he exac ime o disc closu e (poin 4) is diffi-
cul . The e is a ques ion whe he he noise came om me-
chanical easons (e. g. pipeline ib a ions) o om signal
in e e ence. The signal in e e ence is he mos p obable,
because mechanical ib a ions would be isible also on he
accele a ion signal om pump body.
I is in e es ing ha he s onges peak co esponds o
he second p essu e peak downs eam o he check al e
(see figu e 8), bu , a he same momen , he p essu e up-
s eam o he check al e is e y low. I is he ime, when
he disc closes o he second ime.
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
4
012345
0.4
0.2
0
0.2
0.4
0
.
6
Time
[
s
]
Accele a ion [G]
12
4
6
3
5
Fig. 12. Measu emen o he accele a ion on he check al e body
Table 2. Compu ed decele a ion and he maximal e e se eloci y
Ini ial flow eloci y Decele a ion Re e se eloci y
(m s−1)(ms
−2)(ms
−1)
1.3 2.4 0.15
1.9 2.9 0.22
2.5 3.5 0.26
3.4 4.1 0.34
3.8 4.7 0.43
The sys em decele a ion can be easily compu ed om
he figu e 10 using poin s 1 and 2. Maximal e e se flow
eloci y can be ead a he same figu e. These da a a e
lis ed in he able 2 o diffe en ini ial flow eloci ies.
Figu e 13 shows measu ed da a compa ed wi h da a
p o ided by [9]. The ob ained cha ac e is ics is ound be-
ween cha ac e is ics o swing check al e and swing flex
check al e.
03
5
Decele a ion
[
m/s
]
0
0.1
0.2
0.3
0.4
0
.5
Re e se eloci y [m/s]
1
2
42
Swing
check
Swing lex
check
Measu ed swing check
Fig. 13. Maximal e e se eloci y dependence on he sys em de-
cele a ion
4 Discussion
Following lis summa izes impo an e en s in he sys em
( he numbe ing co esponds o he numbe s in he figu es):
1. Pump disconnec ion – he pump s a s decele a ing,
which isible on he di ec measu emen o pump e -
olu ions and p essu e, because he p essu e change is
p opo ional o he second powe o speed change. This
poin is also well ecognizable on he compu ed flow
eloci y, bu accele a ion on he pump body does no
gi e any clue.
2. Change o he flow o ien a ion – can be iden ified
om he compu ed flow eloci y. A low peak can be
ound also in he signal om he p essu e ansduce
ups eam o he check al e.
3. S a o he disc closu e – is easily isible on he p es-
su e eco d a bo h sides (up- and downs eam) o he
check al e.
4. End o he disc closu e – is easily isible on he p es-
su e eco d and also on he compu ed flow a e. I co -
esponds o he maximal e e se flow eloci y. This
poin could be also iden ified on he accele a ion o he
pump body, bu , su p isingly, i was e y difficul o
find exac poin also on he accele a ion o he check
al e body. This eco d is e y noisy.
5. Disc eopening and closing – can be ound on he
p essu e signals and i is isible also on he accele -
a ion o he pump body.
6. Pump sha s op – is defini ely ecognizable wi h scan-
ning he sha , bu i s speed be o e he s op is ques ion-
able, because only one ma k on he sha has been used.
I is also possible o iden i y his poin on he signal
om he accele ome e on he pump body and on he
p essu e a downs eam side o he check al e.
Resul s show ha he highe ini ial flow he mo e in-
ense is decele a ion a e pump disconnec ion. I can be
caused by highe ic ion loss. I is also appa en ha he
highe decele a ion he highe e e se eloci y de elops
be o e he check al e closing, because he disc shu s wi h
longe delay. The check al e migh no be ully open o
lowe flow a es, so closes as e . Ano he explana ion could
be ha highe decele a ion causes swi ls in he check al e
space. These swi ls migh suppo he disc and cause de-
layed closing.
5 Conclusion
The pape is ocused on he measu emen o dynamic cha -
ac e is ic o he swing check al e. An expe imen al ci -
cui has been buil and he swing check al e beha iou
was obse ed du ing ansien e en s occu ing a e pump
disconnec ion om he elec ic ne wo k.
In es iga ed check al e is fi s o a ow o check al es
wi h diffe en cons uc ions, which a e going o be es ed.
This es was supposed o show whe he we a e able o
measu e dynamic cha ac e is ic o he check al e and i i
is possible o desc ibe ansien e en occu ing in he sys-
em. The ollowing expe imen s a e going o include also
eco ding o he check al e disc mo ion.
Acknowledgemen
This wo k has been suppo ed by Technology Agency o
he Czech Republic unde he p ojec Inno a i e esea ch
o check al es o ex eme ope a ing condi ions in ene -
ge ics TH01011352.
Nomencla u e
L(m) pipe leng h be ween p essu e ans-
duce s,
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
5

p(Pa) p essu e, see figu e 5
Q(m3s−1) flow a e,
R(Pa s2m−6) esis ance
S(m2) pipe c oss-sec ion,
(s) ime,
Δ (s) ime s ep,
ρ(kg m−3) densi y.
Re e ences
1. B. W. Ka ney, A. R. Simpson, Jou nal o Hyd aulic Re-
sea ch 45 547 – 554 (2007)
2. C. Chiu, Ame ican Nuclea Socie y 54, 289 – 291
(1987)
3. J. R. T a is, M. D. To ey, Ame ican Socie y o Me-
chanical Enginee s win e annual mee ing, 1 – 9 (Miami
1985)
4. D. Him , V. Hab´
an, P. Dokoupil EPJ Web o Con e -
ences 114 (2016) 02038
5. D. Him , V. Hab´
an, Applied Mechanics and Ma e ials
630, 375 – 382 (2014)
6. K. L. McElhaney, Nuclea Enginee ing and Design 197,
169 – 182 (2000)
7. J. V. Ballun Jou nal o AWWA 99, 3 (2007)
8. W. Rahmeye Nuclea Indus y Check Val e G oup,
1996 Win e Mee ing,1–10(S . Pe e sbu g1996)
9. Val-Ma ic Val e and Manu ac u ing Co p. Dynamic
Cha ac e is ics o Check Val es (2003)
10. J. Jablonsk´
a, M. Kozubko ´
a, EPJ Web o Con e ences
114 (2016) 02049
11. M. Vaˇ
sina, L. H uˇ
z´
ık, A. Bu eˇ
cek, EPJ Web o Con-
e ences 114 (2015) 02131
DOI: 10.1051/
,02036 (2017) 714302036
143
EPJ Web o Con e ences epjcon /201
EFM 2016
6