libraW STATE f^.ANT BOARD May 19^3 SV-210 UNITBD STATES HBPARTMENT OP AOEICTJLTDES Agricultural Besearch Administration Bureau of Sntonology and Plant Qioarantlne AN AIR-PHESSUHE TANK yOR THE PNEUMATIC APPLIOATIOH or LiqUID yUMIGANTS 37 E. H. Walkden, DiYlslon of Cereal and 7ora^ Insect loreetlcatione Bureau of Sntomology and Plant Quarantine, and H. J. Barre, Division of Agricultural Snglneerlng, Bureau of Plant Industry, Soils, and Agricultural Engineering The apparatus descrl'bed herein was developed during the course of Investigations on Insects affecting stored grain, especially that stored In steel tins hy the Commodity Credit Corporation. It was devised to meet the need for efficient, safe, and relatively Inexpen- sive equipment for the application of liquid fumlgants to grain stored In steel "bins. Further, It solves the problem of providing the required energy vhere mechanical or electrical energy Is not available. It Is an adaptation of currently available equipment. An air teink Is simply substituted for the air compressor, which Is a regulair part of conventional equipment. The apparatus consists of two airtight tanks, one to contain the compressed air, and the other the f\imlgant, with a copper tube conp- nectlng them. Provision Is also made for filling the fumlgant tank by means of compressed air, thus eliminating the necessity of exposing the fumlgant when transferring it from the supply drum. The entire equip- ment is Biounted on a wooden frame. Its total weight, empty, is approxi- mately 173 pounds. It is easily carried by two men and restdily placed in an auto truck. The assembled equipment is shown in figure 1 and set up for operation in figure 2. The details of construction are given in figures 3 and k. Operation To operate, the air-pressure tank is filled to I50 pounds of pressure at an ordinary gasoline station. The fumlgant tank may be filled with the aid of the pressure tank (fig. k). Air under relatively low pressure forces the fumlgant from the supply drum into the fumlgant tank. - 2 - To applj the fuaigazit, the pressure Is alloired to Increase in the fumigant task froa the pressure tank, forcing the fnaigant out through the dellyery hose and the spray nossle in a coarse spray. At a pressure of 20 pounds per square Inch in the funigant tank, the rate of flow of the fumigant is approxiaatelj 1 gallon per nisute, depending ux>on the height to which the fuaigant must "be raised* It is usually possible to fill and eiqpty the fumigant tank three times with a single charge of the air tank with pressure of 1^0 pounds per. square inch. The equipnent described abore has the following adrantagest (1) It can be used at grain^storage sites where mechanical energy for operating an air compressor is not arailable. (2) It is relatirely safe from explosion hasaa^ls, through the elimi- nation of an air compressor and gasoline or electric motor. However , the precaution of having the apparatus and the delivery nozzle grotmded should be taken if an inflaamable^ fumigant is being used. (3) The equipment is economical in both initial eoet and operation* (U) It is simple in construction and operation* (5) It is light and mobile. List of Materials The parts required for the oona traction of the appeuratos ar« listed below: Parts for equipment proper — 1 30-gal. range boiler, heavy duty, 1^ pounds* woz^dng pressure (for pressure tank) 1 18-gal. range boiler, 85 pounds' working pressure (for liquid ftmlgant) 1 200-lb. pressure gauge (for pressure tank) 1 75-l^» pressure garage (for fumigant tank) 1 water gauge set with 3^" glass and valved gauge-glass fittings 3 ft. of 3/8" copper tubing with fittings for making connections to pressure and fumigant tanks. (Hotet If copper tubing is not available, l/k* galvanised iron pipe may be substituted. ) 1 1/2" pipe to hose connection. 1 35-ft. length of 1/2" oU- and fumlgant-reslstant, high- pressure (100 lbs.) rubber hose 1 10-ft. length of l/U" high-pressure (l^O lbs.) air hose 1 air tralre (from auto tu1)e) 1 air hose chuck for Insertion In 1/4" ru'b'ber ho8« 2 hose claaps for l/U-" hose 2 hose clanps for l/2" hose 2 ft. of 3/8" galT. Iron pipe for nozzle for fumlgant hose, one end threaded, other end flattened to an opening of the thickness of a hacksaw blade 2 1/U" glohe valres 1 1/2" glohe ralTe 3 1/4" tees 1 1/2" elbow 4 1" X 1/4" nipples 1 3" X 1/2" nipple 2 ft. of 1/2" galvanized Iron pipe (for attaching hose at bottom of fuffllgant tank) Plugs for closing unused outlets In tanks (size and number depend on number and size of unused openings In tanks) 1 1" plug for top of fumlgant tank 1 length of strap Iron 12"3i-l/2"al/4" (to be welded on above plug to fom bar handle) Hote; It wUl probably be necessary to drill and thread openings for various pipe and water gauge connections In the range boilers. Parte for filling apparatus — 2-1/2 ft. of 3/4" galvanized Iron pipe 1 6"x3/4" nipple 3 2"x3/4" nipples 1 3/^" elote valve 2 3/4" elbows 1 3/4" union 1 8-ft. length of 3/4" oil- and fumlgant-reslstant^ lew-pressure rubber hose 2 hose clamps for 3/4" hose 1 1/4" cross 1 1/4" elbow 1 2"xl/4« nipple 1 4"xl/4" nipple 1 5~1^» pressure gauge 1 1/4" petcock 1 air valve (from auto tube) 1 oast Iron plug from fumlgant or steel drum (2-1/2" diameter). This Is to be drilled for 3/4" pipe and 1/4" nipple (air Intake) 2-l/2-ft. length of 3/4" pipe welded In the plug. Pipe to extend 22" through plug (diameter of 55-gal. fumlgant drum) 4"^/4" nipple also welded In plug beside larger pipe, bottom end flush with Inside of plug 2 6" lengths of strap Iron lxl/2"xl/4" (to be welded on above plug to fon bar handle) Im- parts for support lag fraae e l/k*xj* carriage "bolts 8 l/4"x6« aachlM bolti 1 3/8"x2" aachlne tolt k pieces 2"z^"z;|i fir diiMnsion 2 pieces 2«a[l4.'«x6« fir diseasion k ft. of l^xl/S" strap irom 5 ft. of l/2"xL/g" stritp iroa .v^^ Figure 1.— The assembled equipment ready for use. The upright tank contains the liquid, and the horizontal tank contains the compressed air. The pressure gauge on the air tsmk indicates air supply, and the gauge glass on the fumigant tank indicates the amount of fumigant remaining in the tank. In this photograph an air hose is shown connected to the intake valve to indicate how an air line at a supply station may "be used to fill the air tank. Tigure 2. — The equipment set up for operation. Th« desired preasxire in the fumigant tank i3 maintained ty adjustment of the hand-operated valve while the fumigant is "being applied. IS gal. fuml