Vent Guide

Contents I. II. III. IV. V. Background Information Introduction Definitions Example Calculations for Vent Selection Horizontal Cylindrical Storage Tank Vertical Cylindrical Storage Tank Horizontal Rectangular Storage Tank Calculation Tables Precalculated-Horizontal Cylindrical Tanks Precalculated-Vertical Cylindrical Storage Tanks Precalculated-Horizontal Rectangular Storage Tanks Wetted Areas for Horizontal Cylindrical Tanks Wetted Areas for Vertical Cylindrical Tanks Emergency Venting Capacity Gallon Capacity per Foot of Length Vent Selection Morrison Vents-Capacities Vent Combination Examples Morrison Equipment Aboveground Fuel Storage Diagrams Pressure Systems Suction Systems Bulk Storage Page 2 2 3 4 5 6 7 8 9 10 11 12 13 14 15 24 26 28 References NFPA 30 “Flammable and Combustible Liquids Code” 2003 Edition National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02269 UL 142 “Steel Aboveground Tanks” 9th Edition, December 28, 2006 UL Standards for Safety—UL Publication Stock, 333 Pfingsten Road, Northbrook, IL 60062, Tel (847) 272-8800 API Std 2000 “Venting Atmospheric & Low Pressure Storage Tanks” American Petroleum Institute—Fifth Edition, April 1998 1120 L Street, Northwest, Washington, DC 20005 Order #822-20000 PEI RP200 “Recommended Practices for Installation of Aboveground Storage Systems for Motor Vehicle Fueling” Petroleum Equipment Institute, 2003 Edition, P.O. Box 2380. Tulsa, OK, Tel (918) 494-9696 Morrison 325 East 24th Street, Dubuque, Iowa 52001. Tel (563) 583-5701 Page 1 • Morrison Venting Guide Background Information The Morrison Venting Guide was created to assist in equipment selection for aboveground storage tanks. Examples on the next two pages illustrate a vent selection process. It is best to work through the examples before attempting to use any of the tables in this book. Tables include examples for standard sized tanks. The venting capacity charts and wetted area tables were taken directly from NFPA 30 and UL 142. The vent selection chapter includes venting capacities of specific Morrison vents. This data was obtained from results of laboratory testing and engineering calculations. Catalog pages of the Morrison equipment follow the vent capacity chart. Definitions Emergency Venting — Venting sufficient to relieve excessive internal pressure in storage tanks caused by exposure fires. Venting rate may exceed requirements of normal atmospheric and product transfer effects. In such cases, the construction of the tank will determine if additional venting capacity must be provided. Atmospheric Tank — A storage tank that has been designed to operate at pressures from atmospheric through 1.0 PSIG (760 mm Hg through 812 mm Hg) measured at the top of the tank (NFPA 30 Pg. 30-13). Pressure not to exceed 1.0 PSIG under normal operation, and 2.5 PSIG under emergency conditions (PEI RP-200). Pressure Relieving Devices — Defined in NFPA 30 4.2.5.2.3, where entire dependence for emergency relief is placed upon pressure relieving devices, the total venting capacity of both normal and emergency vents shall be enough to prevent rupture of the shell or bottom of the tank if vertical, or of the shell or heads if horizontal. Wetted Area — Exposed surface or shell area of a tank used in determining the venting requirements needed for that size tank in event of an exposure fire. In a horizontal tank, the wetted area is calculated as 75% of the exposed surface area. In a vertical tank, the wetted area is calculated as the first 30 ft. above grade of the exposed shell area of the tank. CFH — Abbreviation for Cubic Feet per Hour used to quantify or measure the airflow and degree of pressure relief for venting calculations. Vent Capacity — The maximum rate of airflow (CFH) recorded under test conditions at a maximum pressure of 2.5 PSI for specific sized emergency vents. This capacity rating is often required to be indicated on the vent itself. Page 2 • Morrison Venting Guide Vent Selection/Capacity Example 1 TANK CAPACITY 10,000 gallons TANK SIZE 10 ft. dia x 17 ft. long Horizontal Cylindrical Storage Tank STEP 1 Precalculated Data for Common Sizes STEP 5 Vent Selection Find tank size on Table A which can be found on page 5. Table lists wetted area and CFH for common sized horizontal tanks. For a 10’ x 17’ tank – wetted area = 518 sq. ft. and required vent capacity = 360,840 CFH. Proceed to Step 5. Options based on size of piping, type of product, flow requirements, required venting capacity and mounting. For the sake of this example, use 2” piping, Class 1B liquid. The normal vent size should be no smaller than the system piping, so a Morrison 2” Fig. 548 (20,200 CFH) is selected. STEP 2 Wetted Area Table Total required venting capacity for this tank example was determined to be 360,840 CFH. Normal venting and emergency venting may be combined to reach this total. Morrison Vent Capacities are listed on Table H, page 12. Since the 6” Emergency Vent (246,130 CFH) can not provide enough additional capacity to meet the requirement, an 8” Emergency Vent (462,000 CFH) is selected. In specifying pressure settings, it is recommended that the Emergency Vent NOT be less than the normal vent. Therefore, the vent specification for this example is as follows: If tank size is NOT listed on Table A, page 5, wetted area can also be found on Table D, page 8. Follow grid for this example – 10’ diameter x 17’ length = 518 sq. ft. Proceed to Step 4. STEP 3 Calculate Wetted Area If the tank size is NOT on either chart, wetted area can be calculated. For Horizontal Tanks, wetted area = 75% of the total exposed surface area. For a 10’ x 17’ tank: 0.75[2(area of each end) + (area of shell)] = wetted area π = 3.14, d = diameter, L = length, WA = wetted area WA = 0.75[(πd2 ÷ 2) +(πdL)] 0.75[((3.14)(102) ÷ 2) + (3.14)(10)(17)] STEP 4 Determine CFH Requirement Use Table F: Venting Capacity Chart on page 10. Wetted area must be known (518 sq. ft.). Since 518 is between 500 and 600 on the chart, interpolation is needed and is done as follows: Difference = 38,000 100 = 392,000 354,000 38,000 x (518-500) 20,200 CFH Emergency Vent - 8” Fig 244 (16 oz pressure) 462,000 CFH Total Venting Provided 482,200 CFH STEP 6 Verification WA = 518 sq. ft. 600 sq. ft. 500 sq. ft. 100 sq. ft. Normal Vent - 2” Fig 548 (8 oz pressure - 1 oz vacuum) Refer to Table I on page 13 showing vent combinations and verify the total CFH figure. Also refer to the product illustrations on pages 23-28 and verify the selection for correct option on material compatibility and mounting requirements. CFH CFH CFH x = 6,840 CFH Total CFH Required: (6,840 + 354,000) = 360,840 CFH Page 3 • Morrison Venting Guide Vent Selection/Capacity Example 2 TANK CAPACITY 10,000 gallons Vertical Cylindrical Storage Tank TANK SIZE 10 ft. dia x 17 ft. high STEP 1 Precalculated Data for Common Sizes STEP 5 Vent Selection Find tank size on Table A which can be found on page 5. Table lists wetted area and CFH for common sized vertical tanks. For a 10’ x 17’ tank – wetted area = 534 sq. ft. and required vent capacity = 366,920 CFH. Proceed to Step 5. Options based on size of piping, type of product, flow requirements, required venting capacity and mounting. For the sake of this example, use 2” piping, Class 1B liquid. The normal vent size should be no smaller than the system piping, so a Morrison 2” Fig. 548 (20,200 CFH) is selected. STEP 2 Wetted Area Table If the tank size is NOT on either chart, wetted area can be calculated. For Vertical Tanks, wetted area = area of shell to elevation not more than 30 ft. above the bottom. Total required venting capacity for this tank example was determined to be 366,920 CFH. Normal venting and emergency venting may be combined to reach this total. Morrison Vent Capacities are listed on Table H, page 12. Since the 6” Emergency Vent (246,130 CFH) can not provide enough additional capacity to meet the requirement, an 8” Emergency Vent (462,000 CFH) is selected. In specifying pressure settings, it is recommended that the Emergency Vent NOT be less than the normal vent. Therefore, the vent specification for this example is as follows: For a 10’ x 17’ tank: Wetted Area = (area of shell) Normal Vent - 2” Fig 548 (8 oz pressure - 1 oz vacuum) 20,200 CFH π = 3.14, d = diameter, L = length, WA = wetted area Emergency Vent - 8” Fig 244 (16 oz pressure) 462,000 CFH Total Venting Provided 482,200 CFH If tank size is NOT listed on Table A, page 5, wetted area can also be found on Table D, page 8. Follow grid for this example – 10’ diameter x 17’ height = 534 sq. ft. Proceed to Step 4. STEP 3 Calculate Wetted Area WA = (πd)L (3.14)(10)(17) WA = 534 sq. ft. STEP 6 Verification STEP 4 Determine CFH Requirement Use Table F: Venting Capacity Chart on page 10. Wetted area must be known (534 sq. ft.). Since 534 is between 500 and 600 on the chart, interpolation is needed and is done as follows: Difference = 38,000 100 600 sq. ft. 500 sq. ft. 100 sq. ft. = 392,000 354,000 38,000 x (534-500) Refer to Table I on page 13 showing vent combinations and verify the total CFH figure. Also refer to the product illustrations on pages 23-28 and verify the selection for correct option on material compatibility and mounting requirements. CFH CFH CFH x = 12,920 CFH Total CFH Required: (12,920 + 354,000) = 366,920 CFH Page 4 • Morrison Venting Guide Vent Selection/Capacity Example 3 TANK CAPACITY 10,000 gallons Horizontal Rectangular Storage Tank TANK SIZE 274”L x 130”W x 65”H (22’-10”L x 10’-10”W x 5’5”H) STEP 1 Precalculated Data for Common Sizes STEP 5 Vent Selection Find tank size on Table C which can be found on page 7. Table lists wetted area and CFH for common sized tanks. For a 274”L x 130”W x 65”H (22’10”L x 10’-10”W x 5’5”H) tank – wetted area = 612 sq. ft. and required vent capacity = 396,320 CFH. Proceed to Step 4. Options based on size of piping, type of product, flow requirements, required venting capacity and mounting. For the sake of this example, use 2” piping, Class 1B liquid. The normal vent size should be no smaller than the system piping, so a Morrison 2” Fig. 548 (20,200 CFH) is selected. STEP 2 Wetted Area Table L = length, W = width, H = height Total required venting capacity for this tank example was determined to be 396,320 CFH. Normal venting and emergency venting may be combined to reach this total. Morrison Vent Capacities are listed on Table H, page 12. Since the 6” Emergency Vent (246,130 CFH) can not provide enough additional capacity to meet the requirement, an 8” Emergency Vent (462,000 CFH) is selected. In specifying pressure settings, it is recommended that the Emergency Vent NOT be less than the normal vent. Therefore, the vent specification for this example is as follows: (274 x 130) + 2(274 x 65) + 2(130 x 65) 144 Normal Vent - 2” Fig 548 (8 oz pressure - 1 oz vacuum) 20,200 CFH Wetted Area = 612 Sq. ft. Emergency Vent - 8” Fig 244 (16 oz pressure) 462,000 CFH Total Venting Provided 482,200 CFH If tank size is NOT listed on Table C, page 7, wetted area can be calculated. For Horizontal Rectangular Tanks, wetted area = exposed shell area excluding the top surface of the tank. For a 274”L x 130”W x 65”H tank: Wetted area = (L x W) = 2(L x H) = 2 (W x H) 144 STEP 3 Determine CFH Requirement Use Table F: Venting Capacity Chart on page 10. Wetted area must be known (612 sq. ft.). Since 534 is between 600 and 700 on the chart, interpolation is needed and is done as follows: Difference = 36,000 100 700 sq. ft. 600 sq. ft. 100 sq. ft. = 428,000 392,000 36,000 x (612-600) CFH CFH CFH STEP 6 Verification Refer to Table I on page 13 showing vent combinations and verify the total CFH figure. Also refer to the product illustrations on pages 23-28 and verify the selection for correct option on material compatibility and mounting requirements. x = 4,320 CFH Total CFH Required: (4,320 + 392,000) = 396,320 CFH Page 5 • Morrison Venting Guide Table A: Pre-Calculated Data Horizontal Cylindrical Tanks TANK WETTED REQ’D VENT EMERGENCY CAPACITY DIAMETER LENGTH AREA CAPACITY VENT SIZE (Gallons) (Ft or In) (Ft-In) (Sq Ft) (CFH) (Inches) 280 36” 5’-2” 47 49,520 3 300 38” 5’-0” 49 51,640 3 500 48” 5’-5” 69 72,650 4 530 46” 6’-0” 71 74,750 4 550 48” 6’-0” 75 78,950 4 1,000 48” 10’-8” 119 124,950 6 1,000 64” 6’-0” 109 114,450 4 1,500 64” 9’-0” 147 154,350 6 2,000 64” 12’-0” 184 193,200 6 2,500 64” 15’-0” 222 223,320 6 3,000 64” 18’-0” 259 243,680 6 3,000 6’-0” 14’-0” 240 233,400 6 4,000 64” 24’-0” 335 281,100 6H 4,000 6’-0” 19’-0” 311 270,060 6H 5,000 8’-0” 13’-4” 326 276,960 6H 6,000 8’-0” 16’-0” 376 300,480 8 8,000 8’-0” 21’-4” 477 344,340 8 10,000 8’-0” 27’-0” 584 385,920 8 10,000 9’-0” 21’-0” 540 369,200 8 10,000 10’-0” 17’-0” 518 360,840 8 10,000 10’-6” 15’-7” 515 359,700 8 12,000 8’-0” 32’-0” 678 420,080 8 12,000 9’-0” 25’-0” 625 401,000 8 12,000 10’-0” 20’-6” 600 392,000 8 12,000 11’-0” 17’-0” 583 385,540 8 15,000 8’-0” 40’-0” 829 470,990 8FL 15,000 10’-6” 23’-5” 703 429,020 8 20,000 10’-0” 34’-2” 922 499,820 8FL 20,000 10’-6” 31’-0” 896 491,760 8FL 20,000 11’-0” 28’-0” 868 483,080 8FL 25,000 10’-6” 38’-6” 1,082 537,530 10 30,000 10’-6” 46’-3” 1,274 568,100 10 Page 6 • Morrison Venting Guide Table B: Pre-Calculated Data Vertical Cylindrical Tanks TANK WETTED REQ’D VENT EMERGENCY CAPACITY DIAMETER LENGTH AREA CAPACITY VENT SIZE (Gallons) (Ft or In) (Ft-In) (Sq Ft) (CFH) (Inches) 280 36” 5’-2” 48 50,580 3 300 38” 5’-0” 49 51,640 3 500 48” 5’-5” 68 71,600 4 530 46” 6’-0” 72 75,800 4 550 48” 6’-0” 75 78,950 4 1,000 48” 10’-8” 134 140,700 6 1,000 64” 6’-0” 100 105,000 4 1,500 64” 9’-0” 151 158,550 6 2,000 64” 12’-0” 201 213,100 6 2,500 64” 15’-0” 251 239,520 6 3,000 64” 18’-0” 301 265,460 6H 3,000 6’-0” 14’-0” 263 245,760 6 4,000 64” 24’-0” 402 312,840 8 4,000 6’-0” 19’-0” 358 291,840 6H 5,000 8’-0” 13’-4” 335 281,100 6H 6,000 8’-0” 16’-0” 402 312,840 8 8,000 8’-0” 21’-4” 536 367,680 8 10,000 8’-0” 27’-0” 678 420,080 8 10,000 9’-0” 21’-0” 593 389,340 8 10,000 10’-0” 17’-0” 534 366,920 8 10,000 10’-6” 15’-7” 514 359,320 8 12,000 8’-0” 32’-0” 754 446,360 8 12,000 9’-0” 25’-0” 706 430,040 8 12,000 10’-0” 20’-6” 644 407,840 8 12,000 11’-0” 17’-0” 587 387,060 8 15,000 8’-0” 40’-0” 754 446,360 8 15,000 10’-6” 23’-5” 764 449,760 8 20,000 10’-0” 34’-2” 942 506,020 10 20,000 10’-6” 31’-0” 990 520,900 10 20,000 11’-0” 28’-0” 967 513,770 10 25,000 10’-6” 38’-6” 990 520,900 10 30,000 10’-6” 46’-3” 990 520,900 10 Page 7 • Morrison Venting Guide Table C: Pre-Calculated Data Horizontal Rectangular Tanks TANK (Ft-In) WETTED AREA (Sq Ft) REQ’D VENT CAPACITY (CFH) EMERGENCY VENT SIZE (Inches) 2’-9” 1’-0” 37 38,950 3 2’-8” 2’-8” 3’-6” 44 46,340 3 250 4’-4” 4’-0” 1’-11” 49 51,640 3 250 6’-8” 2’-9” 1’-11” 54 56,900 3 500 7’-6” 3’-0” 3’-0” 86 90,560 4 500 10’-0” 3’-6” 2’-0” 89 93,740 4 1,000 9’-8” 4’-8” 3’-0” 131 137,550 6 1,000 10’-0” 4’-7” 3’-0” 133 139,650 6 2,000 10’-2” 6’-11” 3’-10” 201 211,560 6 2,000 10’-8” 6’-4” 4’-0” 204 213,240 6 2,500 10’-2” 6’-11” 4’-9” 233 229,480 6 3,000 8’-6” 6’-10” 7’-2” 278 253,560 6H 3,000 13’-9” 5’-5” 5’-5” 282 255,640 6H 4,000 11’-4” 6’-10” 7’-2” 338 282,480 6H 4,000 18’-2” 5’-5” 5’-5” 354 289,920 6H 5,000 22’-9” 5’-5” 5’-5” 428 323,760 8 6,000 13’-8” 10’-10” 5’-5” 413 317,460 8 6,000 16’-5” 6’-10” 7’-2” 445 330,900 8 6,000 27’-4” 5’-5” 5’-5” 503 355,140 8 8,000 18’-2” 10’-10” 5’-5” 511 358,180 8 8,000 21’-11” 6’-10” 7’-2” 562 377,560 8 10,000 22’-10” 10’-10” 5’-5” 612 396,320 8 10,000 27’-5” 6’-10” 7’-2” 678 420,080 8 12,000 27’-4” 10’-10” 5’-5” 710 431,400 8 12,000 32’-11” 6’-10” 7’-2” 795 460,300 8 FL CAPACITY LENGTH WIDTH HEIGHT (Gallons) (Ft-In) (Ft-In) 125 6’-8” 186 Page 8 • Morrison Venting Guide Table D: Approximate Wetted Areas Horizontal Cylindrical Tanks Tank 3 Ft Diameter Tank Length 3 Ft 4 Ft 5 Ft 6 Ft 7 Ft 8 Ft 9 Ft 10 Ft 11 Ft 12 Ft Approximate Wetted Area of Tanks With Flat Heads, Square Feet 32 Tank 3 Ft 4 Ft 5 Ft Diameter Tank Length 39 55 5 Ft 46 65 88 7 Ft 8 Ft 9 Ft 10 Ft 11 Ft 12 Ft Approximate Wetted Area of Tanks With Flat Heads, Square Feet 38 Ft 4 Ft 6 Ft 685 791 902 1013 1129 1244 1036 1155 1272 39 Ft 701 810 923 40 Ft 718 828 944 1060 1181 1301 6 Ft 53 74 100 128 41 Ft 734 847 966 1083 1207 1329 7 Ft 60 84 112 142 173 42 Ft 751 866 987 1107 1233 1357 8 Ft 67 93 124 156 190 226 43 Ft 767 885 1008 1130 1259 1385 9 Ft 74 102 136 170 206 245 286 44 Ft 904 1029 1154 1284 1414 10 Ft 81 112 147 184 223 264 308 353 11 Ft 88 121 159 198 239 283 329 377 12 Ft 95 131 171 213 256 301 350 400 454 509 47 Ft 960 1093 1225 1362 1498 13 Ft 102 140 183 227 272 320 371 424 480 537 48 Ft 979 1114 1248 1388 1527 14 Ft 109 150 194 241 289 339 393 447 506 565 49 Ft 998 1135 1272 1414 1555 15 Ft 116 159 206 255 305 358 414 471 532 594 50 Ft 1157 1295 1440 1583 16 Ft 123 169 218 269 322 377 435 495 558 622 51 Ft 1178 1319 1466 1612 17 Ft 130 178 230 283 338 395 456 518 584 650 52 Ft 1199 1342 1492 1640 18 Ft 137 188 242 298 355 414 477 542 610 678 53 Ft 1220 1366 1518 1668 19 Ft 197 253 312 371 433 499 565 636 707 54 Ft 1246 1389 1544 1696 20 Ft 206 265 326 388 452 520 589 662 735 55 Ft 1263 1413 1570 1725 21 Ft 216 277 340 404 471 541 612 688 763 56 Ft 1437 1593 1753 22 Ft 225 289 354 421 490 562 636 714 792 57 Ft 1460 1622 1781 23 Ft 235 300 368 437 508 584 659 740 820 58 Ft 1484 1648 1809 24 Ft 244 312 383 454 527 605 683 765 848 59 Ft 1507 1674 1839 25 Ft 324 397 470 546 626 706 791 876 60 Ft 1531 1700 1866 26 Ft 336 411 487 565 647 730 817 905 61 Ft 1726 1894 27 Ft 347 425 503 584 668 754 843 933 62 Ft 1752 1923 28 Ft 359 440 520 603 690 777 869 961 63 Ft 1778 1951 29 Ft 371 454 536 621 711 801 895 989 64 Ft 1803 1979 30 Ft 383 468 553 640 732 824 921 1018 65 Ft 1829 2007 31 Ft 395 482 569 659 753 848 947 1046 66 Ft 1855 2036 32 Ft 496 586 678 775 871 973 1074 67 Ft 2064 33 Ft 510 602 697 796 895 999 1103 68 Ft 2092 34 Ft 524 619 715 817 918 1025 1131 69 Ft 2120 35 Ft 539 635 734 838 942 1051 1159 70 Ft 2149 36 Ft 553 652 753 860 966 1077 1187 71 Ft 2177 37 Ft 567 668 772 881 989 1103 1216 72 Ft 2205 428 45 Ft 923 1051 1178 1310 1442 46 Ft 941 1072 1201 1336 1470 SI Units: 1 Ft = 0.30 m; 1 sq ft = 0.09 sq m Source for Chart: NFPA 30, 2003 Edition, Table B-4 Page 9 • Morrison Venting Guide Table E: Approximate Wetted Areas Vertical Cylindrical Tanks (Area of Shell to Elevation Not More Than 30 Ft. Above Bottom) Tank Diameter Tank 3 Ft 4 Ft 5 Ft 6 Ft 7 Ft 8 Ft 9 Ft 10 Ft 11 Ft 12 Ft Wetted Area, Square Feet 3 Ft 28 4 Ft 38 50 5 Ft 47 63 79 6 Ft 56 76 94 113 7 Ft 66 88 110 132 154 8 Ft 75 101 127 151 176 201 9 Ft 85 113 141 170 198 226 255 10 Ft 94 126 157 189 220 251 283 314 11 Ft 103 139 173 208 242 276 311 345 381 12 Ft 113 151 188 227 264 301 340 377 415 452 13 Ft 164 204 246 286 326 368 408 450 490 14 Ft 176 220 265 308 351 396 440 484 528 15 Ft 189 236 284 330 377 424 471 519 566 16 Ft 202 251 302 352 402 453 502 554 603 17 Ft 267 321 374 427 481 534 588 641 18 Ft 283 340 396 452 510 565 623 679 19 Ft 298 359 418 477 538 597 657 716 20 Ft 314 378 440 502 566 628 692 754 21 Ft 397 462 527 594 659 727 792 22 Ft 416 484 552 623 691 761 829 23 Ft 435 506 577 651 722 796 867 24 Ft 454 528 602 679 757 830 905 25 Ft 550 628 708 785 865 943 26 Ft 572 653 736 816 900 980 27 Ft 594 678 764 848 934 1018 28 Ft 616 703 792 879 969 1056 29 Ft 728 821 911 1003 1093 30 Ft 753 849 942 1038 1131 SI Units: 1 Ft = 0.30 m; 1 sq ft = 0.09 sq m Source for Chart: UL 142, 9th Edition, Table A-3 Page 10 • Morrison Venting Guide Table F: Emergency Venting Capacity Wetted Surface Venting Capacity (Sq Ft.) 20 30 40 50 60 70 80 90 100 120 140 160 180 200 250 300 350 400 500 600 700 800 900 1000 1200 1400 1600 1800 2000 2400 2800 and over (CFH) 21,100 31,600 42,100 52,700 63,200 73,700 84,200 94,800 105,000 126,000 147,000 168,000 190,000 211,000 239,000 265,000 288,000 312,000 354,000 392,000 428,000 462,000 493,000 524,000 557,000 587,000 614,000 639,000 662,000 704,000 742,000 Minimal Opening Nominal Pipe Size (Inches) 2 2 3 3 3 4 4 4 4 5 5 5 5 6 6 6 8 8 8 8 8 8 8 10 10 10 10 10 10 10 10 • At 14.7 psia and 60° F (101.4 kPa and 16° C) • Interpolate for intermediate values. • These values taken from NFPA 30, Table 4.2.5.2.3 • These pipe sizes apply only to open vent pipes to the specified diameter not more than 12 inches (0.3m) long and a pressure in tank of not more than 2.5 psig (17.1 kPa). • If tank is to be equipped with a venting device or flame arrestor, the vent opening is to accommodate the venting device or flame arrestor in accordance with the listed CFH. Normal Venting Recommendations NFPA 30 — 2003 4.2.5.1.2 Normal vents shall be sized to be at least as large as the filling or withdrawal connection, whichever is larger, but in no case less than 1-1/4 in. (3 cm) nominal inside diameter. Table G: Gallon Capacity Per Foot of Length Diameter (Inches) 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 U.S. Gallons Per Ft Length 23.50 25.50 27.58 29.74 31.99 34.31 36.72 39.21 41.78 44.43 47.16 49.98 52.88 55.86 58.92 62.06 65.28 68.58 71.97 75.44 78.99 82.62 86.33 90.13 94.00 97.96 102.00 106.12 110.32 114.61 118.97 123.42 127.95 132.56 137.25 142.02 146.88 151.82 156.83 161.93 167.12 Diameter (Inches) 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 U.S. Gallons Per Ft Length 172.38 177.72 183.15 188.66 194.25 199.92 205.67 211.51 217.42 223.42 229.50 235.66 241.90 248.23 254.63 261.12 267.69 274.34 281.07 287.88 294.78 301.76 308.81 315.95 323.18 330.48 337.86 345.33 352.88 360.51 368.22 376.01 383.89 391.84 399.88 408.00 416.00 424.48 433.10 441.80 449.82 Page 12 • Morrison Venting Guide Diameter (Inches) 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 U.S. Gallons Per Ft Length 458.30 467.70 475.89 485.00 493.70 502.70 511.90 521.40 530.24 540.00 549.50 558.51 568.00 577.80 587.52 597.70 607.27 617.26 627.00 638.20 647.74 658.60 668.47 678.95 690.30 700.17 710.90 721.71 732.60 743.58 754.64 765.78 776.99 788.30 799.68 811.14 822.69 834.32 846.03 Table H: Vent Capacity SIZE FIG. NO. MT. CON. PRESSURE oz/sq in. DESCRIPTION CAPACITY CFH DATA SOURCE 2" 351S Female Thds Flame Arrester 0 22,000 Tested at Ohio State Univ. by O. E. Buxton Jr. 1967 2" 351S/748A Female Thds Flame Arrester/Vent 2 15,500 Based on ISU Test of 2" 351S/548-748 - 8 oz by Kavanagh, 1990 2" 351S/748A Female Thds Flame Arrester/Vent 4 15,500 Based on ISU Test of 2" 351S/548-748 - 8 oz by Kavanagh, 1990 2" 351S/748A Female Thds Flame Arrester/Vent 6 15,500 Based on ISU Test of 2" 351S/548-748 - 8 oz by Kavanagh, 1990 2" 351S/748A Female Thds Flame Arrester/Vent 8 15,500 Tested at Iowa State Univ. by P. Kavanagh, 1990 2" 351S/748A Female Thds Flame Arrester/Vent 12 13,000 Based on ISU Test of 2" 351S/548-748 - 16 oz by Kavanagh, 1990 2" 351S/748A Female Thds Tested at Iowa State Univ. by P. Kavanagh, 1990 Flame Arrester/Vent 16 13,000 Female Slip On Updraft Vent 0 27,650 Tested at Iowa State University by P. Kavanagh, 1990 354 Female Slip On Updraft Vent 0 27,650 Tested at Univ. Wisconsin Platteville by L. Lee, 1988 3" 354 Female Slip On Updraft Vent 0 59,000 Tested at Univ. Wisconsin Platteville by L. Lee, 1996 4" 354 Female Thds Updraft Vent 0 116,900 Tested at Continental Disc Corp, 1997 2" 548-748 Female Thds Pressure Vacuum Vent 2 20,200 Based on ISU Test of 2" 548 - 8 oz by Kavanagh, 1960 2" 548-748 Female Thds Pressure Vacuum Vent 4 20,200 Based on ISU Test of 2" 548 - 8 oz by Kavanagh, 1960 2" 548-748 Female Thds Pressure Vacuum Vent 6 20,200 Based on ISU Test of 2" 548 - 8 oz by Kavanagh, 1960 2" 548-748 Female Thds Pressure Vacuum Vent 8 20,200 Tested at Iowa State Univ. by P. Kavanagh, 1960 2" 548-748 Female Thds Pressure Vacuum Vent 12 18,600 Approx. Calculated C.F.H. 2" 548-748 Female Thds Pressure Vacuum Vent 16 18,000 Tested at Iowa State Univ. by P. Kavanagh, 1960 2" 749 Female Thds/Slip On Pressure Vacuum Vent 8 8,500 Tested at Univ. Wisconsin Platteville by L. Lee, 1988 2" 749 Female Thds/Slip On Pressure Vacuum Vent 12 8,500 Tested at Univ. Wisconsin Platteville by L. Lee, 1988 2" 749 CRB Female Thds/Slip On Pressure Vacuum Vent 1.70 11,000 Tested at Univ. Wisconsin Platteville by L. Lee, 1996 3" 548 Female Thds/Slip On Pressure Vacuum Vent 2 43,000 Based on ISU Test of 3" 548 - 8 oz by Kavanagh, 1990 3" 548 Female Thds Pressure Vacuum Vent 4 43,000 Based on ISU Test of 3" 548 - 8 oz by Kavanagh, 1990 3' 548 Female Thds Pressure Vacuum Vent 6 43,000 Based on ISU Test of 3" 548 - 8 oz by Kavanagh, 1990 3" 548 Female Thds Pressure Vacuum Vent 8 43,000 Tested at Iowa State University by P. Kavanagh, 1990 3" 548 Female Thds Pressure Vacuum Vent 12 40,000 Based on ISU Test of 3" 548 - 16 oz by P. Kavanagh, 1990 3" 548 Female Thds Pressure Vacuum Vent 16 40,000 Tested at Iowa State University by P. Kavanagh, 1990 2" 244OM Male Thds Emergency Vent 8 21,100 Approx. Calculated C.F.H. 3" 244 OM Male Thds Emergency Vent 8 59,900 Tested at Continental Disc Corp, 1997 4" 244M Male Thds Emergency Vent 8 109,250 Based on Continental Disc Corp Test of 4" 16 oz 244, 1997 1-1/2" 354 2" 4" 244M Male Thds Emergency Vent 16 109,250 Based on Continental Disc Corp Test of 4" 16 oz 244, 1997 4" 244 Series Female Thds Emergency Vent 8 119,750 Based on Continental Disc Corp Test of 4" 16 oz 244, 1997 4" 244 Series Female Thds Emergency Vent 16 119,750 Based on Continental Disc Corp Test of 4" 16 oz 244, 1997 6" 244 Female Thds Emergency Vent 8 246,130 Based on Continental Disc Corp Test of 6" 16 oz 244, 1997 6" 244 Female Thds Emergency Vent 16 246,130 Tested at Continental Disc Corp, 1997 6" 244F Flanged Emergency Vent 8 298,750 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 6" 244F Flanged Emergency Vent 16 298,750 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 6" 244OH Male/Female Thds Emergency Vent 8 298,750 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 6" 244OH Male/Female Thds Emergency Vent 16 298,750 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 6" 244M Male Thds Emergency Vent 8 246,130 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 6" 244M Male Thds Emergency Vent 16 246,130 Based on Continental Disc Corp Test of 6" 16 oz 244H, 1997 8" 244 Female Thds Female Emergency Vent 8 462,000 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 8" 244 Female Thds Female Emergency Vent 16 462,000 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 8" 244F Flanged Emergency Vent 8 509,550 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 8" 244F Flanged Emergency Vent 16 509,550 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 8" 244M Male Thds Male Emergency Vent 8 453,300 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 8" 244M Male Thds Male Emergency Vent 16 453,300 10" 244F Flanged Flanged Emergency Vent 2.5 808,350 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 10" 244F Flanged Flanged Emergency Vent 8 808,350 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 10" 244F Flanged Emergency Vent 16 808,350 UL Calc based on Continental Disc Corp. Test of 244 Series, 1997 Pressure Vacuum Vent Alarm 8 24,656 Tested at Continental Disc Corp, 1997 2" & 3 " 922 Flanged Female Thds Page 13 • Morrison Venting Guide Table I: Vent Combination Examples MORRISON VENTS CFH MORRISON VENTS CFH 1. 2” 4” Fig. 548 - 4 oz P ................20,200 Fig. 244 - 8 oz P ................119,750 TOTAL CFH ..........................139,950 8. 3” 4” Fig. 548 - 4 oz P ................43,000 Fig. 244 - 8 oz P ................119,750 TOTAL CFH ..........................162,750 2. 2” 6” Fig. 548 - 8 oz P ................20,200 Fig. 244 - 16 oz P..............246,130 TOTAL CFH ..........................266,330 9. 3” 6” Fig. 548 - 8 oz P ................43,000 Fig. 244 - 16 oz P..............246,130 TOTAL CFH ..........................289,130 3. 2” 8” Fig. 548 - 8 oz P ................20,200 Fig. 244 - 16 oz P..............462,000 TOTAL CFH ..........................482,200 10. 3” 8” Fig. 548 - 8 oz P ................43,000 Fig. 244 - 16 oz P..............462,000 TOTAL CFH ..........................505,000 4. 2” Fig. 548 - 8 oz P ................20,200 10” Fig. 244 - 16 oz P..............808,350 TOTAL CFH ..........................828,550 11. 3” Fig. 548 - 8 oz P ................43,000 10” Fig. 244F - 16 oz P............808,350 TOTAL CFH ..........................851,350 5. 2” Fig. 548 - 8 oz P ................20,200 10” Fig. 244F - 8 oz P ..............808,350 TOTAL CFH ..........................828,550 12. 3” Fig. 548 - 8 oz P ................43,000 10” Fig. 244F - 8 oz P ..............808,350 TOTAL CFH ..........................851,350 6. 2” Fig. 548 - 8 oz P ................20,200 10” Fig. 244F - 2.5 oz P...........808,350 TOTAL CFH ..........................828,550 13. 3” Fig. 548 - 8 oz P ................43,000 10” Fig. 244F - 2.5 oz P...........808,350 TOTAL CFH ..........................851,350 7. 2” 2” 14. 3” 2” Fig. 548 - 8 oz P ................20,200 Fig. 922 - 8 oz P ................24,656 TOTAL CFH ..........................44,856 Page 14 • Morrison Venting Guide Fig. 548 - 8 oz P ................43,000 Fig. 922 - 8 oz P ................24,656 TOTAL CFH ..........................67,650 244 Series Emergency Vent Emergency vent (pressure relief only) used on aboveground storage tanks, as a code requirement that helps prevent the tanks from becoming over-pressurized and rupturing if exposed to fire. UL listed except for 2". Fig.244 Description The 244 emergency vent consists of a body and a black powder coated cover (2" not powder coated) that moves up and down on a center pin. Pressure inside the tank forces the cover to lift up off the vent seat, allowing air to exhaust. The center pin guides the movement. When pressure falls the cover lowers back down onto seat and the vent is automatically reset. Code Compliance When properly sized for the tank, this vent will conform to the requirements of NFPA 30, 30A, UL 142, UL 2244, API 2000, and PEI RP200. Fig. No. 244 & 244O Opening Pressure Size Setting (oz/sq in) 4" 6" 8" 244F& 244OF 6" 8" 10" 244M & 244OM Ship Venting Mounting Weight Capacity Connection (lbs) (*Estimated CFH @ 2.5 PSI) 8.0 16.0 8.0 16.0 8.0 16.0 10.65 21.00 15.50 33.15 34.70 68.00 119,750 Female NPT/BSP 119,750 Female NPT 246,130 Female NPT/BSP 246,130 Female NPT 462,000 Female NPT 462,000 Female NPT 8.0 16.0 8.0 16.0 2.5 8.0 16.0 24.8 44.2 42.00 75.00 32.00 71.00 125.00 298,750 298,750 509,550 509,550 808,350 808,350 808,350 8.0 8.0 8.0 16.0 8.0 16.0 8.0 16.0 1.0 5.75 11.55 21.25 19.45 35.00 34.00 68.00 21,100* 59,900 119,750 119,750 246,130 246,130 453,300 453,300 Flanged Flanged Flanged Flanged Flanged Flanged Flanged WARNING...The 244 emergency vent is for “emergency pressure relief only” and must be used in conjunction with a “normal vent” or pressure vacuum vent such as a Morrison Fig. 354, 548, 748 or 749. WARNING...The 244 emergency vent must be properly sized and selected for each specific tank application in order to meet the proper “venting capacity” requirements. See the Morrison Vent Guide for further instructions. Material and Configuration Options Aluminum Body or Iron Body…suffix (I) indicates iron. Metal-to-Metal Seat (brass) or Soft Seat (Viton®)…suffix (O) indicates o-ring. Male/Female NPT/BSP or Flanged Mounting Connection…suffix (M) indicates male, and suffix (F) indicates flanged. Opening Pressure Setting…settings indicated are approximate. T=Tall Body...8" only order for use on tite wrapped tanks. Emergency vent should be set higher than the normal vent so the normal vent operates first. Use 16 oz. o-ring to comply with pressure decay test. Contact factory for assistance. Fig. No. 244OI Opening Pressure Size Setting (oz/sq in) 4" 6" (2" and 3" OM only) 2" 3" 4" 6" 8" Male NPT/BSP Male NPT/BSP Male NPT Male NPT/BSP Male NPT Male NPT/BSP Male NPT Male NPT 244OH 6" 8.0 16.0 21.50 41.40 298,750 298,750 Female NPT Female NPT 244OMH 6" 8.0 16.0 23.00 42.9 298,750 298,750 Male NPT Male NPT Fig.244F Fig.244M 8" 244OMI (3" OMI only) 3" 4" 6" 8" 244OMT 8.0 16.0 8.0 16.0 8.0 16.0 Ship Venting Mounting Weight Capacity Connection (lbs) (*Estimated CFH @ 2.5 PSI) 13.65 119,750 Female NPT 24.00 119,750 Female NPT 20.63 246,130 Female NPT 38.28 246,130 Female NPT 44.33 462,000 Female NPT 77.63 462,000 Female NPT 8" 8.0 8.0 16.0 8.0 16.0 8.0 16.0 8.00 16.36 26.06 27.76 43.31 34.63 75.36 59,900 119,750 119,750 246,130 246,130 453,300 453,300 Male NPT Male NPT Male NPT Male NPT Male NPT Male NPT Male NPT 8.0 16.00 40.5 71.5 453,300 453,300 Male NPT Male NPT WARNING…Do not fill or unload fuel from a storage tank unless it is certain that the tank vents will operate properly. Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142, NFPA 30 & 30A, and API 650 and in accordance with all applicable local, state and federal laws. In normal operation, dust and debris can accumulate in vent openings and block air passages. Certain atmospheric conditions such as a sudden drop in temperature, below freezing temperatures, and freezing rain can cause moisture to enter the vent and freeze which can restrict internal movement of vent mechanisms and block air passages. All storage tank vent air passages must be completely free of restriction and all vent mechanisms must have free movement in order to insure proper operation. Any restriction of airflow can cause excessive pressure or vacuum to build up in the storage tank, which can result in structural damage to the tank, fuel spillage, property damage, fire, injury, and death. Monthly inspection, and immediate inspection during freezing conditions, by someone familiar with the proper operation of storage tank vents, is required to insure venting devices are functioning properly before filling or unloading a tank. Normal vents such as pressure vacuum and updraft vents for aboveground storage tanks should be sized according to NFPA 30 (2008) 21.4.3 Page 15 • Morrison Venting Guide 244A 244C Flanged Adaptor Companion Flange The 244A can be used with either Fig. 244F or Fig. 143A. The 244C can be used with either Fig. 244F or Fig. 143A. Construction Details Construction Details Carbon steel welded rim and skirt. Cast iron with NPT “center port” I.D. Size Weight 6" (eight 7/8" holes on 9½" B.C.) 8" (eight 7/8" holes on 11¾" B.C.) 10" (twelve 1" holes on 14¼" B.C.) 12.0 lbs 19.0 lbs 20.0 lbs Fig. 244C Size Weight 8" (eight 7/8" holes on 11¾" B.C. w/8" NPT I.D.) 10" (twelve 1" holes on 14¼" B.C. w/10" NPT I.D.) 27.0 lbs 36.0 lbs 244N Pipe Nipple Construction Details Available (T.O.E.) Threaded One End or (T.B.E.) Threaded Both Ends. Carbon steel —NPT Fig. 244N Page 16 • Morrison Venting Guide Size Weight 4" x 8" 6" x 8" 8" x 8" 8" x 12" 7.00 lbs 13.0 lbs 20.0 lbs 28.0 lbs Pressure/Vaccum Emergency Vents 548 Series 748A Series Pressure/Vacuum Vent Pressure/Vacuum Vent With Gauge Hatch…for “normal” venting of aboveground storage tanks. Allows tank to “breathe” during filling and discharging operations. Pressure/vacuum poppets seal vapors in the tank when pressure is equalized. This vent must be used in conjunction with an emergency vent and it is RECOMMENDED that the opening pressure setting is set below that of the emergency vent so the normal vent operates first. Settings are approximate. For “normal” venting of aboveground storage tanks. Allows tank to “breathe” during filling and discharging operations. Pressure/ vacuum poppets seal vapors in the tank when pressure is equalized. This vent must be used in conjunction with an emergency vent and it is RECOMMENDED that the opening pressure setting is set below that of the emergency vent so the normal vent operates first. Settings are approximate. Fig. 548 Fig. 748 Construction Details Construction Details Fig. 548…brass body and hood Brass (raised) metal-to-metal seats/poppets. Fig. 548A…aluminum body and hood. Brass (raised) metal-tometal seats/poppets. 2" available with British Pipe Threads. Standard Features 1. Threaded gauge hatch for manual gauging access. 2. Horizontal discharge with field-adjustable, tripolar orientation. Fig. 548 Fig. 548A Pressure Vacuum Ship Ship Size Setting Setting Weight Weight (oz/sq in) (oz/sq in) (lbs) (lbs) 2" 3" 2.0 4.0 6.0 8.0 12.0 16.0 2.0 4.0 6.0 8.0 12.0 16.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 13.25 13.75 14.25 14.75 15.75 17.00 26.25 27.25 28.25 28.75 29.25 33.25 7.00 8.75 8.50 9.50 10.50 11.25 12.25 13.75 15.00 15.75 15.75 20.50 Venting Capacity (CFH) (@2.5 PSI) 20,200 20,200 20,200 20,200 18,600 18,600 43,000 43,000 43,000 43,000 40,000 40,000 WARNING…Do not fill or unload fuel from a storage tank unless it is certain that the tank vents will operate properly. Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142, NFPA 30 & 30A, and API 650 and in accordance with all applicable local, state and federal laws. In normal operation, dust and debris can accumulate in vent openings and block air passages. Certain atmospheric conditions such as a sudden drop in temperature, below freezing temperatures, and freezing rain can cause moisture to enter the vent and freeze which can restrict internal movement of vent mechanisms and block air passages. All storage tank vent air passages must be completely free of restriction and all vent mechanisms must have free movement in order to insure proper operation. Any restriction of airflow can cause excessive pressure or vacuum to build up in the storage tank, which can result in structural damage to the tank, fuel spillage, property damage, fire, injury, and death. Monthly inspection, and immediate inspection during freezing conditions, by someone familiar with the proper operation of storage tank vents, is required to insure venting devices are functioning properly before filling or unloading a tank. Brass (raised) metal-to-metal seats/poppets; Aluminum body and hood. Standard Features 1. Horizontal discharge with field-adjustable, tripolar orientation. 2. Optional pressure discharge NPT hood. Pressure Vacuum Size Setting Setting (oz/sq in) (oz/sq in) 2" 2.0 4.0 6.0 8.0 12.0 16.0 Fig. 748A Ship Weight (lbs) Venting Capacity (CFH) (@2.5 PSI) 6.75 7.5 8.25 9.25 10.50 11.00 20,200 20,200 20,200 20,200 18,600 18,600 1.0 1.0 1.0 1.0 1.0 1.0 748ALT Pressure-Vacuum Vent For Ag-Chemical…vent valve used with aqua-ammonia and ag-chemical products allowing tank to “breathe” during filling/discharging operations. Poppets seal vapors in the tank when pressure is equalized. Settings are approximate. Construction Details Size…2" NPT Body and Cap…aluminum Poppets…Teflon® coated aluminum Screens…stainless steel Normal vents such as pressure vacuum and updraft vents for aboveground storage tanks should be sized according to NFPA 30 (2008) 21.4.3 Page 17 • Morrison Venting Guide Option (must specify)…male NPT connection for dryer application Option…pressure discharge NPT hood Pressure Vacuum Ship Venting Setting Setting Weight Capacity (oz/sq in) (oz/sq in) (lbs) (CFH) (@ 2.5 PSI) 8.0 1.0 5.5 20,200 16.0 1.0 5.5 18,000 32.0 1.0 5.5 NA Fig. 748ALT 749 Series Pressure/Vacuum Vent Vent valve used on underground and low volume aboveground tanks for motor fueling. Vent allows tank to “breathe” during filling and discharging operations. Poppets seal vapors in the tanks when pressure is equalized. Settings are approximate. Construction Details Body…aluminum Pressure Poppet…aluminum Vacuum Poppet…brass Pipe Seal…Buna-N Screen…brass Fig. 749…2" NPT Fig. 749S…2" slip-on style Fig. 749CRB…2" NPT CARB approval (95-15A) for stage I and II (8 oz for stage I only).Viton® o-rings on pressure poppet. Fig. 749CRBS…2" slip-on style CARB approval (95-15A) for stage I and II (8 oz for stage I only). Viton® o-rings on pressure poppet. Fig. 749BSP…same as Fig. 749, but with British pipe threads. Fig. 749 Fig. No. 749 749S WARNING…Fig. 749 P/V vent must only be used in conjunction with motor fueling and/or low capacity flow. Fluid handling in lines larger than that used for retail service stations can cause tank to rupture or implode. 749CRB 749CRBS 749BSP Pressure Vacuum Setting Setting (oz/in2) (oz/in2) Ship Weight (lbs) Venting Capacity (CFH) (@ 2.5 PSI) 8.0 12.0 0.5 0.5 1.0 1.0 8,500 8,500 3"W.C. 8 oz 8" W.C. 5 oz 1.45 1.45 11,000 8.0 12.0 0.5 0.5 1.0 1.0 8,500 8,500 922 Combination Vent/Overfill Alarm The Fig. 922 Combination Vent/Overfill Alarm is a fully mechanical, high intensity audible alarm that alerts you when your tank is near full while also allowing your tank to breathe during filling and dispensing operations. The unit is equipped with a whistle which incorporates a 2” or 3” full port pressure/ vacuum vent. The unit can be set to activate at 90% fill height by adjusting the cable length to the float device. The adjustment tool is provided. The unit attaches to a 2” or 3” N.P.T. pipe mounted on the tank. Minimum fill rate for alarm to operate is 20 GPM. WARNING…In order for 2” Pressure relief setting ...... 6 oz/in2 or 8 oz/in2 Fig. 922 2” Vacuum relief setting ...... 1 oz/in2 Construction Details 2” Venting capacity (CFH) ... 30,120 or 30,300 Body…anodized aluminum Screens…stainless steel Rainguard…anodized aluminum Seals…Viton® Ball…Teflon Float…stainless steel 2” Weight................................ 7.5 lbs 3” Pressure relief setting ...... 6 oz/in2 or 8 oz/in2 3” Vacuum relief setting ...... 1 oz/in2 3” Venting capacity (CFH) ... 43,020 or 44,160 3” Weight................................ 5.25 lbs the Fig. 922 to function properly all emergency vents, fill connections, tank openings and piping connections must be airtight. Emergency vent should be set at least 2 oz. higher than the Fig. 922. NOTE…922 not for use on vapor recovery systems. WARNING…Do not fill or unload fuel from a storage tank unless it is certain that the tank vents will operate properly. Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142, NFPA 30 & 30A, and API 650 and in accordance with all applicable local, state and federal laws. In normal operation, dust and debris can accumulate in vent openings and block air passages. Certain atmospheric conditions such as a sudden drop in temperature, below freezing temperatures, and freezing rain can cause moisture to enter the vent and freeze which can restrict internal movement of vent mechanisms and block air passages. All storage tank vent air passages must be completely free of restriction and all vent mechanisms must have free movement in order to insure proper operation. Any restriction of airflow can cause excessive pressure or vacuum to build up in the storage tank, which can result in structural damage to the tank, fuel spillage, property damage, fire, injury, and death. Monthly inspection, and immediate inspection during freezing conditions, by someone familiar with the proper operation of storage tank vents, is required to insure venting devices are functioning properly before filling or unloading a tank. Normal vents such as pressure vacuum and updraft vents for aboveground storage tanks should be sized according to NFPA 30 (2008) 21.4.3 Page 18 • Morrison Venting Guide 351S 351S & 748A Fig. 351S Flame Arrester Size Weight 2" NPT 31.0 lbs Standard Features Body…cast iron Cover…cast iron Cap…brass Arrester Plates…stainless steel 1. 2. Gauge opening cap. Vapor relief capacity at 2.5 PSI = 22,000 CFH Restrictions and Warning 2. Do not use with acetylene, carbon disulfide, etheleneoxide or hydrogen gases. For use with normal hydrocarbon flames such as gasoline in air. Routine inspection is required to ensure airways are clear and free of debris. Blocked airways can cause structural deformation of the tank. Construction Details Fig.351S…Flame arrester Fig. 748A…Pressure/vacuum vent Fig. 748 Pressure Vacuum Ship Size Setting Setting Weight (oz/sq in) (oz/sq in) (lbs) 2" 2.0 4.0 6.0 8.0 12.0 16.0 1.0 1.0 1.0 1.0 1.0 1.0 354 155S Updraft Vent Double Outlet Vent “Open” vent used on underground and aboveground tanks for motor fueling. Vent allows tank to “breathe” during filling/dispensing operations. NOTE…Open vents will allow unrestricted evaporation of product. 42.00 42.50 42.75 43.50 44.50 45.75 Venting Capacity (CFH) (@2.5 PSI) 15,500 15,500 15,500 15,500 13,000 13,000 Aluminum T-style vent used primarily on small fuel oil storage tanks. Fig. 155S Outlet ports on either side of the inlet with 20 mesh stainless steel screen keeps debris out of the airway. Fig. 354 Construction Details Body…aluminum Cap…aluminum Screen…40 mesh brass Fig. 351S w/748A Fig. 748A…same vent featured in pressure/vacuum vent section. Construction Details 1. Flame Arrester With 748A Vent…pressure vacuum type flame arrester to help prevent the transmission of heat and/or an ignition source into the tank. Open (non-pressure vacuum type) flame arrester to help prevent the transmission of heat and/or an ignition source into the tank. Size (slip-on) Ship Weight (lbs) Venting Capacity (CFH) 1½"* 2"* 3" 4" 0.75 0.75 1.50 2.25 27,650 27,650 59,000 116,900 Fig. 155…threaded (NPT) Fig. 155BSP…2" with British Pipe Threads Fig. 155FA…2" with flash arrestor Fig. 155S…slip-on Size Weight ¾" 1" 1¼" 1½" 2" 3" .25 lbs .50 lbs .50 lbs .75 lbs 1.0 lbs 2.5 lbs NOTE…Open vents will allow unrestricted evaporation of product. WARNING…Do not fill or unload fuel from a storage tank unless it is certain that the tank vents will operate properly. Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142, NFPA 30 & 30A, and API 650 and in accordance with all applicable local, state and federal laws. In normal operation, dust and debris can accumulate in vent openings and block air passages. Certain atmospheric conditions such as a sudden drop in temperature, below freezing temperatures, and freezing rain can cause moisture to enter the vent and freeze which can restrict internal movement of vent mechanisms and block air passages. All storage tank vent air passages must be completely free of restriction and all vent mechanisms must have free movement in order to insure proper operation. Any restriction of airflow can cause excessive pressure or vacuum to build up in the storage tank, which can result in structural damage to the tank, fuel spillage, property damage, fire, injury, and death. Monthly inspection, and immediate inspection during freezing conditions, by someone familiar with the proper operation of storage tank vents, is required to insure venting devices are functioning properly before filling or unloading a tank. Normal vents such as pressure vacuum and updraft vents for aboveground storage tanks should be sized according to NFPA 30 (2008) 21.4.3 Page 19 • Morrison Venting Guide 818 Series 918 Series Clock Gauge Clock Gauge Alarm Patent 5144836…for measuring liquid level in aboveground storage tanks. Gauge mounts on top of tank and is activated by a float connected to a cable. Readout is on a 12 hour clock face. Utilizes the Fig. 818 style clock gauge with a built-in high level warning alarm. Contains a battery powered, intrinsically safe, alarm unit that is mounted remote from gauge. Alarm is set for desired level during installation and can be reset at any time for a change in alarm level requirements. Patent Number 5144836 and 5649450. Small hand = feet or meters Large hand = inches or centimeters Gauge can be read 20-30 ft away to within 1/8 ". Maximum measurement is 12 ft. Fig. 818 Fig. 818F…with female threads. Fig. 818MET…with metric face. Fig. 918F…with female threads. Fig. 818MEF…with metric face and female threads. Fig. 818MEB…with metric face and British pipe threads. Fig. 818I…floating suction gauge. Fig. 818MET Fig. 918SS…with stainless steel parts for some chemicals. Indicates change in liquid level. Fig. 918MEB…with metric face and British pipe threads. Construction Details Fig. 918MET…with metric face. Body…aluminum with 2" NPT/BSP Male/Female connection Float…stainless steel Cable…stainless steel Standard Features 1. 2. 3. 4. Vapor tight construction. Swivel 360° for desired orientation. High level/low level decals for application on lens cover. Float fits through a 2" schedule 40 and 80 pipe nipple, and works with a Fig. 419, 2" Morrison drop tube. Options (must specify) 1. 2. Fig. 918 Metric face plate (range = 3 m, 60 cm). Extension leader for extended mounting above the tank. Fig. 918MET Fig. 918MEF…with metric face and female threads. Construction Details Gauge Unit…Fig. 818 clock gauge style (same standard and optional features). Fig. 918 gauge has alarm dial and internal switch. Alarm dial is accessible on the clock face. Electrical junction box and lead wires for remote mounting are also included. Alarm Unit… Plastic weatherproof housing. 90 decibel high pitched “beep” cycle alarm. Features a push-button test switch. Powered by two 9 volt batteries (included). Only alarm box is UL Listed. 918TCP Construction Details Overfill Alarm Sensor…The single point level sensor is immersed in the tank through a 2” NPT female opening and is supported by a nylon liquid tight cable connector, Teflon tubing and wire. Provides an audible alarm for either a high or low level warning. Incorporates an alarm box and a single-point level sensor. Contains a battery powered, intrinsically safe, alarm unit that is mounted remote from gauge. Alarm Box… Weatherproof, intrinsically safe, 90 decibel alarm that operates on two 9-volt batteries. It features a membrane-type test/cancel button. The single point level sensor is immersed in the tank through a 2" NPT Female opening and is supported by a nylon liquid tight cable connector, Teflon tubing and wire. The high or low activation point is set at the factory. The order length should be equal to the distance from the top of the 2" tank opening to the desired activation level. Only alarm box is UL Listed. Fig. 918TCP Float and Weight… Stainless steel. The low level activation point can be set up to 113". The interstitial monitor level can be set up to 113" as well. Available with either 0-53" probe or 53"-113" probe. Page 20 • Morrison Venting Guide FMMASO-91 Series Specifications Overfill Prevention Valve for Used Oil Systems Valve Body and Collar…anodized aluminum Float…polypropylene Float Rod and Valve Spool…brass O-ring seals…Viton® Hardware… stainless and plated steel Patent 5007450…valve with optional alarm for use on used oil evacuation systems which use an air operated pump. Fig. FMMASO-91S Operation 1. Valve installs in 2" bung opening at the top of the tank. Air supply is routed through the valve before going to the pump. 2. The valve will close off air supply to the pump when liquid level reaches 90% of tank capacity. Air is diverted to the audible signal on models FMMASO-91S and FMMASO91EXS. Models Fig. (FMMASO-91)…standard valve without audible signal. Fig. (FMMASO-91S)…standard valve with audible signal. BSP Part Number FMMASOB-91S. Fig. (FMMASO-91EX)…same as Fig. FMMASO-91, but with extended body for use on double wall or vaulted tanks. Fig. (FMMASO-91EXS)…same as Fig. FMMASO-91EX, but with audible signal. Fig. (FMMATO-91)…high level turn-on for sump applications (no signal). 3. The valve will reset as liquid is removed from the tank and air pressure to the valve is turned off. 618 Simplex Tank Gauge Used for measuring liquid level in aboveground storage tanks. Best suited for vertical tanks over 12 ft high. Gauge readout by tape which passes over an indicator mounted at 3 ft height on the side of the tank. Activated mechanically by a float that rests on the liquid level. Float is connected to a cable that runs up through the top of the tank, across two pulleys, and down the side of the tank to the indicator position. Construction Details Standard Features Tape sizes available: tape for up to 31' tank and tape for 31' to 50' tank 1. 2. 3. 4. Round copper float Tape Stainless steel cable Vapor seal Options (must specify) 1. 2. 3. 4. Round stainless steel float with swivel (101/8 " diameter). Brass cylindrical float (1¾" diameter, 32" long) with center swivel. Stainless steel cylindrical float (1¾" diameter, 32" long) with center swivel. Metric not available. NOTE…Installation instructions are included, piping is not included. Installation Collar…2" NPT Air inlet and outlet…¼" NPT Overall length (including float and audible signal)…20" Shipping weight…2.0 lbs Shipping weight (Fig. FMMASO-91EX)…4.5 lbs NOTE…Cylindrical floats will pass through a 2" opening. Page 21 • Morrison Venting Guide 9095A Construction Details AST Overfill Prevention Valve Patent 5832953…installed at the fill port of an aboveground storage tank. Used in a tight fill application, the valve terminates flow of product when the liquid level reaches a preset warning level (90-95% full). The valve is installed on a standard NPT male connection when used with the quick disconnect or female adaptor. The 2" valve can be used in conjunction with the Morrison Fig. 518 and 515 lines of AST spill containers for added spill protection. When installed to manufacturers requirements, the OPV valve can help eliminate environmentally hazardous spills. All models are supplied with an adaptor to mount to Morrison Fig. 419 aluminum drop tubes. A test mechanism is also sold separately. The test mechanism allows a technician to pull on the test line at any time during the filling process to actuate the float and stop the fill. This allows a technician to verify the valve is working properly.ULC listed. Adaptor…aluminum (hard-coat anodized) Female adaptor…ductile iron Body…anodized aluminum Plunger and dashpot…brass or nickel plated Shaft, linkages and hardware…stainless steel Piping…steel (epoxy coated) Features 1. Adjustable float (1½")…for setting the precise level of shutoff in the field and allowing it to be done using standard length pipe nipples. 2. Immediate and cushioned shutoff…full flow up to within 1-2 seconds of closing and no abrupt kickback or jolt, or startling noise in the line when valve closes. 3. One piece adaptor/coupler casting…no extra seams and joints to leak when top portion is under pressure from closing. 4. Dry disconnect…after shut off product is allowed to automatically drain from the highest point so fill nozzle can be removed without spilling. 5. Simple mechanics…minimum moving parts. Shutoff is activated by basic hydraulic principle with no springs, levers or complicated sequence leading to closure. Fig. 9095A Fig 9095A-AV…compatible with aviation fuel Code Compliance Size Weight 2" valve w/2" male quick disconnect x 4" female threads* 2" valve w/2" female threads x 4" female threads 2" valve w/2" male quick disconnect remote fill adaptor 2" valve w/3" male quick disconnect x 4" female threads 2" valve w/3" female threads x 4" female threads 3" valve w/3" male quick disconnect x 6" female threads* 3" valve w/3" female threads x 6" female threads 3" valve w/3" male quick disconnect remote fill adaptor *BSP Threads Available 14.1 lbs 14.1 lbs 12.6 lbs 14.1 lbs 14.1 lbs 29.0 lbs 38.0 lbs 26.0 lbs NFPA 30, 30A, UFC, BOCA, SBCCI/SFC and PEI RP200. NOTE…For use on clean product only. Not suitable for motor oil. Size Maximum Pressure Maximum Flow Maximum Viscosity 2" 100PSI 125gpm 150 Centistokes 3" 100PSI 300gpm 60 Centistokes 9095S Construction Details AST Overfill Prevention Valve Adaptor…aluminum (hard-coat anodized) Body…anodized aluminum Float...polypropylene Plunger and dashpot…brass Upper tube and float guard...brass Shut off mechanism...anodized aluminum Designed for use on low profile tanks that require a high level shut-off. The valve terminates the fill when the product reaches the preset level. The valve can be retrofitted on existing tanks and fits into a 2” opening. A tight fill connection is required for operation. Features Sold with either a 2" Part F Male Threaded Adaptor or a 2" Part A Female Threaded Adaptor. 1. Adjustable float…for setting the precise level of shutoff in the field. The vertical float allows for installation in openings in proximity to the tank walls. 2. Immediate and cushioned shutoff…full flow up to within 1-2 seconds of closing and no abrupt kickback or jolt, or startling noise in the line when valve closes. 3. Dry disconnect…after shut off product is allowed to automatically drain from the highest point so fill nozzle can be removed without spilling. 4. Simple mechanics…minimum moving parts. Shutoff is activated by basic hydraulic principle with no springs, levers or complicated sequence leading to closure. Typical flow rate is 53 GPM at 30 PSI. Size 2" Maximum Pressure Maximum Viscosity 100PSI 150 Centistokes NOTE…For use on clean product only. Not suitable for motor oil. Fig. 9095S NOTE…Cannot be installed in a drop tube. Page 22 • Morrison Venting Guide 517 Series 518 Series 3½ Gallon AST Spill Container 7½ Gallon AST Spill Container Installed on aboveground storage tanks for the purpose of containing small spills and Fig. 517 drips from the fill nozzle. 3½ gallon capacity. Steel construction. Lockable and white powder coated. ULC listed. Installed on aboveground storage tanks for the purpose of containing small spills and drips from the fill nozzle. 7½ gallon capacity. Lockable with drain valve and vented lid. Connects to 4" male (NPT) riser, and is white powder coated. Female NPT x Female NPT. Fig. 517…spill containment. Male (NPT) x Male (NPT) connection. Fig. 517F…spill containment. Female (NPT) x Female (NPT) connection. Fig. 518CC…same as 518 only with center tank mount opening. Fig. 517WO…waste oil containment– Removable screen on inside of container so used filters, etc. can be allowed to drain. Male NPT riser connection. Size Fig. 518M…2" or 4" Male. Size Weight 2" 4" 20.0 lbs 26.0 lbs Construction Details Weight 2" (517, 517F, and 517WO) 4" (517, 517F, and 517WO) Fig. 518 Body and lid (14 ga.)…steel Drain Valve…brass Drain O-ring…Viton® 10.5 lbs 11.0 lbs 515 Series AST Remote Spill Container For use on aboveground storage tanks for the purpose of containing fuel spillage during remote tank filling operations. 15 gallon capacity. 12 gauge steel construction. Lockable lid, and powder coated white for durability. 1" NPT drain with locking ball valve included. Choice of one or two fill ports, 2", 3", 4" or combination. 2" bung for pump. Single column base is easily adjustable. Fig. 515 Fig. 515OEM…same as 515 but without the pedestal and no rear ports, with top fill openings and with 4, ½" weld taps on the back. The 515OEM is not ULC Listed. Front Back (Single) Back (Double) Side 28" - 42" Page 23 • Morrison Venting Guide Aboveground Fuel Storage - Pressure System Horizontal cylindrical tank with top fill and remote dispenser Fig. 548 Pressure Vacuum Vent Fig. 818 Clock Gauge Fig. 244 Emergency Vent Page 24 • Morrison Venting Guide 12 Ft. Minimum (Alarm Fig. 918) Fig 517 or 518 Spill Container Fig. 305C Fill Cap Fig. 323 & 323C Vapor Recovery Adaptor w/ Cap Fig. 9095A Overfill Prevention Valve Submersible Pump Fig. 235 or 535 Gate Valve Fig. 285 Fig. 346 Series Line Strainer External Emergency Valve Fig. 710 Solenoid Valve Fig. 419 Drop Tube Electrical Line Fig. 128DI Frost-Proof Drain Valve Morrison Bros. Co. • P.O. Box 238 • Dubuque, IA 52004 • Ph: 563-583-5701 • Fax: 563-583-5028 Fig. 636 Emergency Shut-off Valve Aboveground Fuel Storage - Pressure System Rectangular double-wall tank with remote fill and side mounted dispenser Fig. 548 Pressure Vacuum Vent Fig. 9095A Overfill 12 Ft. Minimum to Grade Level Prevention Valve Fig. 918 Clock Fig. 244 Gauge Emergency w/Alarm Vent Fig. 244 Emergency Vent (Interstitial) Submersible Pump Fig. 235 or 535 Gate Valve Fig. 285 Line Strainer Fig. 346 Series External Emergency Valve Fig. 710 Solenoid Valve Page 25 • Morrison Venting Guide Electrical Line Fig. 515 Remote Spill Container Fig. 800A & 800DC Adaptor w/ Dust Cap Fig. 246 Check Valve Fig. 419 Drop Tube Fig. 691B Locking Ball Valve Fig. 323 & 323C Vapor Recovery Adaptor w/ Cap Fig. 918 Overfill Alarm Morrison Bros. Co. • P.O. Box 238 • Dubuque, IA 52004 • Ph: 563-583-5701 • Fax: 563-583-5028 Dispenser Fig. 636 Emergency Shut-off Valve Aboveground Fuel Storage - Suction System Horizontal cylindrical tank with top fill and top mounted pump Fig. 922 Combination Pressure Vacuum Vent / Overfill Alarm Fig. 244 Emergency Vent Page 26 • Morrison Venting Guide 12 Ft. Minimum Fig 517 or 518 Spill Container Fig. 305C Fill Cap Fig. 9095A Overfill Prevention Valve Fig. 818 Clock Gauge Suction Pump Fig. 419 Drop Tube Fig. 157 Suction Pipe Strainer Fig. 128DI Frost-Proof Drain Valve Morrison Bros. Co. • P.O. Box 238 • Dubuque, IA 52004 • Ph: 563-583-5701 • Fax: 563-583-5028 Aboveground Fuel Storage - Suction System Rectangular Double-Wall Tank With Remote Fill and Remote Pump Page 27 • Morrison Venting Guide AST Bulk Storage Normal (P/V) Vent - and with Flame Arrestor Emergency Vent (Threaded or Flanged) Fig. 548 Fig. 244 Fig. 351S / 748A Allows tank to breathe during normal filling and withdrawing operations. Match vent size to fill and withdrawal piping. Fig. 244F Allows tank to exhaust excessive pressure if exposed to pool fire. Size to be determined by tank size and type. Simplex Tank Gauge Pipe Nipple 12" height minimum Internal Emergency Valve Automatic shut-off of product flow in event of fire and/or impact. Poppet is located inside tank. Pipe Nipple or Flange Adaptor Manhole 31 ft 40 ft 50 ft Indicates liquid level (inventory) in the tank. In feet and inches. Fig. 272 Gate Valve with Expansion Relief Expansion Relief feature allows excess pressure due to temperature gain to bleed back to tank. Fig. 535 Frost Proof Drain Valve Fig. 128 Fig. 618 Allows water on bottom of tank to be drained off. Seat is located up inside the tank shell. Page 28 • Morrison Venting Guide Emergency Generator or Fuel Oil Suction System Fig 517 or 518 Spill Container Fig. 305 & 305C Male Quick Fig. 9095A Disconnect & Overfill Cap Prevention Valve Fig. 818 or 918 Clock Gauge Fig. 244 Emergency Vent Fig. 354 or Fig. 922 Combination Pressure Vacuum 12 Ft. Minimum Fig. 244 to Grade Level Emergency Vent (Interstitial) Fig. 244 Emergency Vent Fig. 235 or Fig. 285 535 Gate Line Strainer Valve Fig. 246A Swing Check (Return) Fig. 346 Series External Emergency Valve Fig. 710 Solenoid Valve Page 29 • Morrison Venting Guide Fig. 78DI Expansion Relief Valve (Supply) Fig. 419 Drop Tube Fig. 539 Diffuser Fig. 539 Diffuser Fig. 157 Suction Pipe Strainer (Generator or Boiler) Morrison Bros. Co. • P.O. Box 238 • Dubuque, IA 52004 • Ph: 800-553-4840 • Fax: 563-583-5028