The URL can be used to link to this page

Home My WebLink AboutDOMESTIC TANKS:J p m F PROM ME 'ad Italian groscurdt Runhud "I by PERC In Overall pufannunco ranhing for Proleclim Coatings applied OnUndprgrcundRopulleTanks LU& still -Z, 4, J j PROUDLY FiNiSHED1 WiTTA. SH E Pra YNN - WAX LIA3 M's IIMN Containing Our ftrids Energy - - r Ur Containing OurWorld's Energy'K I Ft OUTSIDEDIAMETER I w'o � General Specifications Conforms to the latest edition of the ASME code for Pressure Vessels, Section Vlll, Division 1. Complies with NFPA 58. i Rated at 250 psig from -20° F. to 1250 F. All tanks maybe evacuated to a full (14.7 psi) vacuum, i Vessel Finish: Coated with epoxy red powder, ( Tanks coated With the epoxy powder must be buried). For Aboveground use, tanks may be coated with TGIC powder. Applicable federal, state or local regulations maycontain specific requirements for protective coatings and cathodic protection, The purchaser and Installer are responsible for compliance with all federal, state or local regulations, I All vessels dimensions are a WATER OUTSIDE CAPACITY DIAMETER 120 wg. 464.2 L 260 wg. 946.3 L 320 wg. 1211.2 L 500 wg. 1892.5 L 1000 wg. 3785.0 L 24" 609.E mm S-._._. 1.511 800.1 mm 800.1 mm 950.5 mm 1040A mm OVERALL LENGTH I FLOAT GAUGE 1 SERVAEI LVE / RELIEF VALVE FITTINGS LAYOUT DOME WITHDRAWAL NOTICE.. VALVE AGUG VESSEL D 3xlmate IMENSIONAL INFORMATION f HEAD TYPE Rip H eml Hem! Heml Hemi 1 OVERALL II OVERALL I- LEG LENGTH HEIGHT WIDTH 5' - 5 13/16" 3` - 0" 1671,3mm 1 911.4 mm T - 2 1/2" 3' - 7 1/2" mm 1104.9mm 3/4" 3'- 7 1/2" 279 mm mm2197,1 1104.9 - 9' 10" , 4-1 7/16" 2997.2 mm 11255.7 mm 15' -10 13/16" T 4 5/16" 4846.E mm ' 1344.E mm 10 118" 257.2 mm 12 3/4" 321.9mm 12 3/4" 323.9 mm 15" 381.0 mm 16 412.8 mm ANODE �!r CONNECTION ® ' FILLER O.�VALVE DOME LEG WEIGHT SPACING 3'-0" 914.4 mm 31.611 1161.8-- mm 41.0 1/4" 1225.6 mm 5'-0" 1524.0 mm 9'-0" 2743.2 mm 245 lbs. 111,1 kg 4721bs. 14.1'ka NAME PLATE QUANTITY FULL PER LOAD STACK 96 12 63 ' 9 45 g 30 .6 15 5 Rev; Jan. 27, 2016 Why Tanks Corrode Underground steel tanks corrode due to an electrochemical reaction between the tank and the surrounding soil. The process of corrosion occurs due to small voltage differences on the steel surface that result in the flow of DC current from one location to another. Where current flows from the tank into the soil corrosion occurs. This location is called the anode In a corrosion circuit. Where current flows from the soil to the tank, no corrosion occurs. The progress of corrosion is determined by the amount of current flowing between the anode and the cathode and whether the locations of the anode/ cathode remain constant over time. Corrosion rates are generally higher in wet soil environments since the conductivity of the soil promotes the flow of DC current in the corrosion circuit. Corrosion generally exhibits itself on underground tanks in either a general overall rusting or more commonly, a pitting attack. Pit locations may result from metallurgical conditions of the steel surface or soil variations such as rocks, salts, fertilizer, moisture concentration, oxygen concentration, etc. Preventing Corrosion Protecting underground tanks from corrosion is easilyachieved bytho use Of two commonly applied protection methods: ' external coating and wj cathodic prote' ction. These two methods are complementary = _ and should be used in conjunction with , the other. An effective external protective coating insulates the steel from the soil environment, thus preventing the flow of corrosion current from the anode to the cathode. An effective external coating can protect over 99% of the tank surface area. However, no coating is perfect. Damage from construction or soil stresses create tiny defects, which may result in accelerated corrosion at the defect. Cathodic protection prevents corrosion at those defects by applying DC current from an external source, forcing the tank to became cathode. Application of sufficient DC current to the tank will prevent any corrosion from occurring. The two general types of cathodic protection systems are sacrificial and impressed current. Sacrificial systems are used when the amount of current required for the protection Is small, such as in underground propane tanks. Impressed current systems are more commonly used for large structures such as large diameter Pipelines. Electrical isolation of the tank from metallic piping systems and electrical grounds is critical for the cathodic protection system's effectiveness. How Sacrificial Cathodic Protection Works Sacrificial systems work by creating a galvanic connection between two different metals. The most commomanode 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 about -0.50 volts referenced to a copper sulfate electrode. The open circuit potential of magnesium is about -1.55V to-1.80V. By connecting the two metals together, the difference of 1 to 1.25V volts 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 10,000 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 backfilled 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 backfill. The anode and backfill 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 for various size tanks based on conservative design assumptions.; This chart covers soil conditions UP to 10,000 ohm -centimeter resistivity. , Resistivities higher than 10,000 ohm -centimeter generally represent ivery 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. All underground steel pipe should be externally coated with a corrosion resistant material. The serviceline 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 connectinnc If another metallic material such as copper is used for service piping, the pipe should be electrically isolated from the tank at the fill pipe connection. Copper and steel create a galvanic couple that will accelerate corrosion of the steel tank when directly connected to copper piping. Generally, copper piping does not require cathodic protection. Soil Type Fertile. Soils cia �,.; .. Y,. ,, Sand, '�— Gravel, Rocky Areas Tank Cap 5 to 5000 ohm cm" 5000 to 10000 ohm -cm (gal.) SIZe Qty .' Alloy :'. y- size Q ry• Alloy 120 9#°, 1 _; H-1..• 9# 9# 250 9' 2. H-1 325 9# 2 H-1 500 9# 2 H-1 1000 17° 2 - H-1: 9# 4 H-1 1500 1Z#'': 2 ` ': H i 9# 4 1 H-1 2000 Based on 90% effective extemal coating, 2 ma11t2 current density, and 3 yearAnodelife. I Anode installation 1. Determine size and quantity of anodes from application chart. 2. When a single anode is installed, it should be located near the tank center on either side of tank. h3. When multiple anodes are installed, space them evenly around the tank. See examples below. i MnF anon w. 4.Anodes are shipped in either cardboard boxes or m papersacks. Remove outer container and burythe cloth anode. If anode is supplied in plastic bag, remove la before installing. p 5. Install anodes approximately two to three feet from the t at least as deep as the center line of the tank. Anodes w( in locations with permanent moisture, so generally the the better. 6-After placing the anode, stretch out the anode connecth and extend over to a connection point on the tank fill pip 7. Cover the anode with approximately six inches of back pour 5 gallons of water on the anode to saturate the pr backfill. Water is necessary to activate the anode. 8. Connect the anode wire to the tank with a low el( resistance connection. Examples are threaded stud i tank fill pipe or any accessible metallic connection point tank. All connections should be coated with a moisture material. 9. Ideally, the tank connection is made in the area of the tl pipe within the covered dome. With access to the anodf subsequent testing of the tank can include measurenil anode output and verification of performance. 10.Verify performance of the anode using an appropriate procedure. i-wal gged bag (and best leper wire and in the to the ik fill wire, nt of test r � i i Mechanical Connection Under Dome Cathodic Protection Testing Procedure Equipment 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 DC scale. Clip red test lead connector to an uncoated metallic, area of the tank, preferably to the fill pipe muitivalve. A good solid connection is very important. (DO NOT connect to shroud). STEP 2: Insertthe blacktest lead into theZommon jack on the meter, and connect the opposite end of 'the lead to a charged reference electrode (% 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 I/ cell deeper into the soil. STEP 4: Record all four meter readings on an appropriate form. The least of all four readings should be i 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 end. 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. Caution: Do not allow electrode to ccntact oil, road salts, or other substances that may contaminates the solution by absorption through porous plug. Do not allow electrode to freeze. Ideal for use as a first stage regulator on any domestic si; Installations requiring up to 1,500.000 BTU's per hour. The Pressure to an intermediate pressure of approximately 10 PI '311 91'ino, 0019droamauen LV34037E;tdg %' FNPT I W F.NPT I /7," Ma;dmurrt flow based on Intel pressure 20 PSIG higher than the setting and delivery pressure 2o% rower Then the selling. ropane gas ulator is factory set to reduce container —�9'-00 ' 1.500,000 and delivery pressure 20% lower than the regulator Provides accurate first stage regulation In two Intermediate pressure of 5 to 10 PSIG. Als-stage bulk tank systems. Reduce tank pressure Na an o used to supply high pressure burners for applications like industrial furnaces or boilers. Also Incorporated in multiple cylinder installations. 'O rCOG11'o11a 0D�sillc�rr611n�ucrra I i_va4o3SR_ Mi:03Ti; i 1" F NPT U/d303SRg '12" F NPT LV"03 - �/„ LV$$03SR9a F. POL LV=iJ193TP,96 F.NPT When used for Onal stage pressure control. must either Incorporate Integral With NFPA Pamphlet 5& " Maximum flow based on Inlet preasure 20 PSIG higher than the regulator sE 4-. 92 Designed to reduce first slege pressure of 5 to 20 PSIG d[ Ideal for medium commercial installations, multiple cylinder Yes I 2,500,000 valve or separate relief valve should be specified In accordance and delivery pressure 201% lower than the selling. to burner pressure, normally 11" w.c. atiari.,.,a , .., ----,