Pile technology test report: Flapper nozzle assembly

摘要

The functional operation of the flapper nozzle was tested by charging slugs through it while water flow rates up to 48.4 gpm and inlet header pressures up to 400 psig. were maintained. Comparative damage to the slugs by the flapper nozzle and an H-type inlet nozzle was determined by charging slugs through the nozzles with a 105-D type air cylinder charging machine under conditions of no water flow or lubrication. The effect of the nozzle design on the inlet pressure fluctuations was determined while using 0.140, 0.200, and 0.285 inlet orifices as well as no orifice. The flapper nozzles operated satisfactorily for all conditions tested, without leakage from the flapper valve or the needle valve. However, the flapper valve became loosened on the shaft after several operations, and it is felt that the design should be changed to insure that it is rigidly fastened to the shaft at all times. Damage to the slugs by either the flapper nozzle or the H-type inlet nozzle was negligible. The ribs of the process tube caused the normal parallel, longitudinal scratches the length of the slugs. Maximum fluctuations of (+-) 5 psig were noted on the inlet pressure gauge reading, at compared with a maximum of about (+-) 7 psig for standard nozzle Panellit pressure.