Accession Number : AD0764358

Title :   Evaluation of the Hazard of Static Electricity in Nonmetallic Pol Systems-Static Effects in Handling Jet Fuel in Fiberglass Reinforced Plastic Pipe.

Descriptive Note : Technical rept. Jun 71-Jun 72,

Corporate Author : ESSO RESEARCH AND ENGINEERING CO LINDEN N J PRODUCTS RESEARCH DIV

Personal Author(s) : Bachman,Kenneth C. ; Munday,J. C.

Report Date : JUN 1973

Pagination or Media Count : 217

Abstract : There is increasing interest in pipe for minimizing contamination in ground handling of aviation fuels. This report presents the results of a litera-ture search and experimental study conducted to determine if static electricity hazards would be increased by substituting FRP for metal pipe in such systems. Experiments were conducted in 6 inch diameter, matched volume, carbon steel and Bondstrand 2000 pipes at four fuel conductivi-ties between 0.2 and 5.5 CU and at flow rates between 200 and 1500 GPM at controlled temperatures. Charge generation in the pipes was low (2.5 micro C/m3 maximum with 0.9 CU fuel at 1200 GPM in steel); generation in FRP was generally less than in steel. Relaxation in FRP pipe depended on fuel polarity; on the average, relaxation was 8 percent faster, with negatively- charged fuel and 30 percent slower with positively-charged fuel than in steel. The slower relaxation should not prevent the use of FRP in Air Force hydrant systems handling JP-4 where a minimum of 2 minutes residence time is available downstream of filter- separators. Voltages up to 55 kv were measured on the FRP pipe and sparks up to 1/ 2 inch long could be discharged from ungrounded metal components on the FRP pipe. These effects should be of no concern in underground installations; methods for eliminating them in above-ground installations are recommended. An evaluation of the A. O. Smith Static Charge Reducer (SCR) showed that it was more efficient with positively-than negatively-charged fuel and that deposit-buildup could reduce its efficiency. Available data suggest that static electricity hazards might exist downstream of an SCR although the average charge level is below 30 micro C/m3. (Author-PL)

Descriptors :   (*AVIATION FUELS, HAZARDS), (*PIPES, STATIC ELECTRICITY), GLASS TEXTILES, ELECTROSTATIC FIELDS, JET ENGINE FUELS, BIBLIOGRAPHIES, REINFORCED PLASTICS

Subject Categories : Pumps, Filters, Pipes, Tubing, Fittings & Vlvs
      Safety Engineering
      Fuels

Distribution Statement : APPROVED FOR PUBLIC RELEASE