HomeMy WebLinkAboutGAS TANK INFORMATION3OVEGRQUPlDiUNDEfi6R0UND C
PROPANE
& research
COUNCIL
Ranked 4i by PERC
In overall Performance ranking
for Prcteclire ConGnos applied
on Underg�oand Pmpane Tanks
PROUDLY FINISHED WITH
SIZERM inWILLIAMS.
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R sFp2 ..`too
1.
RINITY
Our WOr(d's Energy-
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TRINITY*
Containing OurWorld's Energy'
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General Specifications
I to the latest edition of the ASME code for
Vessels, Section Vill, Division 1. Compiles with
58.
A at 250 psig from -20' F. to 125' F. All tanks may be
:uated to a full (14.7 psi) vacuum.
sel Finish: Coated with epoxy red powder. ( Tanks coated
the epoxy powder must be buried). For Aboveground use,
s may be coated with TGIC powder.
!cable federal, state or local regulations may contain
�iflc requirements for protective coatings and cathodic
M/CDAI I 1 =hIn"TIJ
�- - WITHDRAWAL
VALVE
O
FLOAT
GAUGE L.P. TICE ANODE
CONNECTION
' ® ,' FILLER
O VALVE
O i
SERVICE / `� NAME
MULTIVALVE PLATE
RELIEF
VALVE
pro
ectlon. The purchaser and installer are responsible for
co
Hance with all federal, state or local regulations.
FITTINGS LAYOUT UNDER DOME
AGUG VESSEL DIMENSIONAL INFORMATION
All ve',
els dimensions are approx"Imate
W
u
ER
OUTSIDE HEAD
OVERALL
OVERALL
LEG
LEG
WEIGHT
QUANTITY
CAP
CITY
DIAMETER TYPE
LENGTH
HEIGHT
WIDTH
SPACING
ILOADISTACK
FULL PER
12Q
wg.
24" Ellip
6- 5 13116"
3' - 0"
10 1/8"
T - 0"
245 lbs.
96 12
401
r2 L
609.6 mm
1671.3mm 1
911.4 mm
257.2 mm
914.4 mm
111.1 kg.
250;
wg.
31.5" Hemi
7' - 2 1/2"
3' - 7 1/2"
12 3/4"
3' - 6"
472 lbs.
63 9
94
3 L
800.1 mm
2197.1 mm
1104.9 mm
323.9 mm
1066.8 mm
214.1 kg.
32
31.5" Hem!
8'-11 3/4
3'- 7 1/2"
12 3/4"
4- 0 1/4"
588 lbs.
45 9
121
2L
00.1 m
2736.9 mm
1104.9
323.9 mm
1225.6 mm
266.7 kg.
500
g.
37.42" Hem!
9' -10"
V -1 7/16"
15"
5' - 0"
871 lbs.
30 6
1892.5
L
950.5 mm
2997.2 mm
1255.7 mm
381.0 mm
1524.0 mm
395.1 kg
I 00C
wg.
1
40.96" Hem!
15' -10 13/16"
4' - 4 5/16"
16 1/4"
9' - 0"
1729 Vbs.
15 5
37811„0
L
1040.4 mm
4846.6 mm
1344.6 mm
412.8 mm
2743.2 mm
784.3 kg
Rev. Jan, 27, 2016
Why T''' nks Corrode
Under 'found steel tanks corrode due to an electrochemical reaction
betwee' the tank and the surrounding soil. The process of corrosion
occurs' ue to small voltage differences on the steel surface that result
In the f w of DC current from one location to another. Where current
flows fr m the tank into the soil corrosion occurs. This location is called
the ano a in a corrosion circuit. Where currentflows from the soil to the
tank, nc corrosion occurs. The progress of corrosion is determined by
the amo Int of current flowing between the anode and the cathode and
whether�he locations of the anode/cathode remain constant overtime.
Corrosio 1 rates are generally higher in wet soil environments since the
conductl ity of the soil promotes the flow of DC current in the corrosion
circuit. �
c;orrosior� generally exhibits itself on underground tanks in either a
general oi erall rusting or more commonly, a pitting attack. Pit locations
may resufrom metallurgical conditions of the steel suraface or soil
variations , uch as rocks, salts, fertilizer, moisture concentration, oxygen
;oncentra on, etc.
>�; ;,s, Preventing Corrosion
;•r,�=� �;�, . ._�... = �...-�: :• .:,� Protecting underground
tanks from corrosion is
easilyachieved bythe use
Of two commonly applied
Protection methods:
external coating and
-- cathodic
These two Protection.
methods
.�� are complementary
-_' - and should be used in
conjunction with the
other. An effective
external
coating insul es the steel from the soil environment, thus Prole revetiln e
the flow of co ,rIosion current from the anode to the cathode. An effective
axternalcoatid' can protect over99%ofthe tanksurfacearea. However,
10 coating is perfect Damage from construction or soil stresses create
my defects, w ich may result in accelerated corrosion at the defect.
'athodle prote lion prevents corrosion at those defects by applying
i t current fr an external source, forcing the tank to became
athode, Appli anon of sufficient DC currentto the tankwili prevent any
irrosfon from ccurring. The two general types of cathodic protection
Istems are sa ificial and impressed current Sacrificial systems are
,ad when the mount of current required for the protection is small,
ich as in and ground propane tanks. Impressed current systems
e more comet' my used for large structures such as large diameter
Wines. Electrcal isolation of the tank from metallic piping systems
d electrical gr ''unds is critical for the cathodic protection system's
'etiveness.
w Sacrificial G thodic Protection Works
Irificiai system work by creating a galvanic connection between two
different metals. The most common anode material is magnesium,
Which when coupled to steel results in DC current flow from the
Magnesium to the steel. The open circuit potential of steel is bout -0.50 volts referenced to a copper sulfate electrode. The open circuit a
potential of magnesium is about -1.55V to-1.80V. By connecting the
two metals together, the difference of 1 to 1.25Vvolts results in current
flow to the tank that overcomes the natural corrosion cells that exist on
the tank. With this current available to the tank, no corrosion occurs.
Magnesium Anodes
There are a variety of anode sizes and alloys used for cathodic
Protection. The two primary alloys are designed as H-1 (or AZ63) and
High Potential. The H-1 alloy is produced from recycled magnesium
and has an open circuit potential of approximately —1.55V. This alloy
is well suited for protection of underground propane tanks. The High
Potential alloy is 99% pure magnesium having an open circuit potential
up to -1.8V. This alloy should be used for soil applications over 1 apo
ohm -cm resistivity.
The two most common anode sizes used for underground propane
tanks are 9 lb. and 171b. The size designation relates to the metal weight.
10' of #12 TW Insulated wire is attached to the anodes. Anodes are
then backfflled in a mixture of gypsum, bentonite, and sodium sulfate
to lower the electrical resistance of the anode to soil. The mixture is a
low cost, nonhazardous, electrically conductive backlill. The anode and
back -fill is then packaged in a cotton bag and ;either a cardboard box or
paper bag. Actual shipping weight of these anodes with backfill is 27
lb. and 45 lb.
Application Recommendations
Magnesium anodes can protect underground tanks in most soil
conditions. The H-1 alloy is generally very effective, The following chart
Provides size and quantity recommendations forvarlous size tanks based
on conservative design assumptions. This chart covers soil conditions
UP to 10,000 ohm -centimeter resistivity. Resisfivities higher than
10,000 ohm -centimeter generally represent very dry soils. Verification
of soil resistivity can be performed through soil analysis. Contact us
for design recommendations in locations where soil resistivities exceed
10,000 ohm -cm, or if there is no effective external coating on the tank.
The propane service line from the tank to the house also must be
considered in the cathodic protection design, unless the service line
is plastic. Ail underground steel pipe should be externally coated with
a corrosion resistant material. The service line should be electrically
isolated at the house with an insulating fitting or union. If service pipe
Is less than 50' in length, the tank anodes will provide sufficient current
to protect both tank and pipe. For longer lengths of pipe, an additional
anode may be required at the house connections,
If another metallic material such as copper is used for service piping,
the pipe should be electrically isolated from the tank at the fill pip connection. Copper and steel create a galvanic couple that Will acceleratee
corrosion of the steel tank when directly connected to copper piping.
Generally, copper piping does not require cathodic protection.
S ii :rertilesotis Glay -' San(t_,wel Rue
Type ::_,.^.,.
I ,a�dyFlLuain==; Areas
T k Cap. taY5Ii00 dhir=cm ' 5000 to 10000 ohm-em
u ` 1zer� Y Q y ?Ajlt4 , Size My. Alloy
1120
1�.. 1 H-1
150-IRw'3 «1#1%r 9# 1 H-1
250JA
y5s1r'11r`r 9# 2 H-1
25`� 9# 2 H-1
r`
.H
o0 '`IPrFI lK' 9# 2 H-1
000 t? `z rk 71H 'l 9#
5o0j1a .c -1r 9# 4 H-1
000 f`1k7' =3 [rl: 9# 6 H-1
I
*Based on 0 % effective external coating, 2 maM current density, and So-
yearAnodf 11fe.
Anode In allation
1. Date ine size and quantity of anodes from application chart.
2. Whet a single anode is installed, it should be located near the
tank!enter on either side of tank.
S. When; multiple anodes are installed, space them evenly around
the ta' k. See examples below.
7 ani de 2 anodes 4 anodes
C7:50
4.Anode' are shipped in either cardboard boxes or multi -wall
paper 'acks. Remove outer container and bury the cloth bagged
anode. ! If anode is supplied in plastic bag, remove plastic bag
before installing.
5. lnstall node$approximately two to three feet from the tank and
at leas ; s deep as the center line of the tank. Anodes work best
in loca ons with permanent moisture, so generally the deeper
the bet ir.
6.After p, icing the anode, stretch out the anode connection wire
and ext nd over to a connection point on the tank fill pipe.
7. Cover t e anode with approximately six inches of backffll and
pour 5 allons of water on the anode to saturate the prepared
backfiil. Water is necessary to activate the anode.
8. Connec t the anode wire to the tank with a low electrical
resistan a connection. Examples are threaded stud on' the
tank fill ipe or any accessible metallic connection point to the
tank. A connections should be coated with a moisture -proof
material
9. ideally, t ie tank connection is made in the area of the tank fill
pipe witt in the covered dome. With access to the anode wire,
subsequent testing of the tank can include measurement of
anode ou put and verification of performance.
10.Verify p ormance of the anode using an appropriate test
r" �1
M8chanic ..--"onnection Under Dome
Cathodic Protection nesting Procedure
E .ulpment Needed: Digital Voltmeter, Red Test Lead Min.12' Long
& Black Lead Min. 2' Long, Reference Electrode (Copper/Copper
Sulphate Half -Cell)
STEP 1: Using a digital voltmeter insert the red test lead into the Volt
jack of the meter and select the 2 or 20 volt OC scale. Clip red test
lead connector to an uncoated metallic area of the tank, preferably
to the fill pipe multivaive. A good solid connection Is very important.
(DO NOT connect to shroud).
STEP 2: Insertthe black test lead into the Common jack on the meter,
and connectthe opposite end of the lead to a charged reference
electrode (%x cell).
STEP 3: Remove protective cap from the porous plug at bottom end
of electrode. Place porous plug end into native soil (remove grass if
necessary) at four locations around the tank (one on each side of the
tank, and one at each end of the tank). If difficulty is encountered
obtaining readings, moisten soil with water or dig Y cell deeper into
the soil.
STEP 4: Record all four meter readings an an appropriate form. The
least of all four readings should be a minimum of-0.850v or more
negative. {Note: If any of the four readings are below (less negative)
-0.850v then the tank is not fully protected}.
Charging Reference Electrode
STEP 1: Unscrew and remove porous plug end of new reference
.electrode. Add deionized or distilled water to the copper sulfate
crystals, filling electrode completely. The solution will turn blue in
color and there should always be excess crystals at the bottom of
the tube. DO NOT USE TAP WATER.
STEP 2: Replace porous plug end of electrode and place in an upright
position so that the porous plug and is facing in the down position
and let stand for 1 hour before use. This will allow the porous plug
to become completely saturated before use.
dantiom Do not allow electrode to contact oil, road sells, or other
substances that may contaminate the solution by absorption
through porous plug. Do not allow electrode to freeze.
for use as a first stage regulator on any domestic size ASAQE or DOT container in propane gas
ations requiring up to 1,500,000 BTU's per hour. The regulator is factory set to reduce container V� `
ure to an intermediate pressure of approximately 10 PSIG.
115YPU
eirina Okfairmnation
�Va;403TRV9 "/4�' FNPT %' FNPT 7/32'10 PSIG vvcr %JUMIL 1,500,000
9:00ximum now basedl on inlet pressure 20 PSIG higher then the regulator selling and delivery pressure 20% lower than the regulator
e Qng and delivery pressure 20% lowerthan the setting.
accurate first stage regulation In two -stage bulk tank systems, Reduce tank pressure to an
ate pressure of 5 to 10 PSIG. Also used to supply high pressure burners for applications like
furnaces or boilers. Also incorporated In multiple cylinder installations.
inn Information
11V14403TR4 P NPT 10 5 10
')(44035R9 2 F. NPT 5 1-5
4Y4403TR9 �10 6-10 Yes 2,500,000
L� 4403SR96 F- POL
LV,4403TR96 '/"FNPT 5 1-5
5-10
men used for final stage pressure control, must ellharIncorporate Integral rellefvalve or separate relief valve should be specMed in accordance
th NFPA Pamphlet 5s.
ximum now based on Inlet pleasure 20 PSIG higher than the regulator setting and delivery pressure 2091. lower than the setting.
ined to reduce first stage pressure of 5 to 20 PSIG down to burner pressure, normally 11" w.c.
for medium commercial Installations, multiple cylinder installations and normal domestic loads.
lering Information
FNPT
#28 at 10 9" to 13" Over Inlet 935,000
%" F NPT Drill PSiG W.C.
l" F. NPT I Inlet
d on 10 PSIG Inlet and 9"w c. delivery pressure
The LV34038R Back Mount Regulator is designed to reduce first stage pressure of 5-10 PSiG down to
burnt pressure normally 11" w.c. Designed as a second stage regulator for smaller applications with flow
requi ements up to 450,000 BTU/hr. and are ideal for homes, mobile homes, and cottages.
®rZing Information
*Ma
16
K , " "/"FNPT 11"w.c.At10
R FNPT 3 „ 7/32 9" t° 13" Over inlet 450 000 FNPT PSIG inlet we
flow based on 10 PSIG inlet and g" w,c, delivery pressure.
9
115TE0
3