and maintenance manual for the particularequipment or as directed by the MRCs.1. All samples should be taken from circu-lating systems, or immediately upon shutdown,while the hydraulic fluid is within 5°C (9°F) ofnormal system operating temperature. Systemsnot up to temperature may provide nonrepre-sentative samples of system dirt and watercontent, and such samples should either beavoided or so indicated on the analysis report. Thefirst oil coming from the sampling point shouldbe discarded, since it can be very dirty and doesnot represent the system. As a general rule, avolume of oil equivalent to one to two times thevolume of oil contained in the sampling line andvalve should be drained before the sample istaken.2. Ideally, the sample should be taken froma valve installed specifically for sampling. Whensampling valves are not installed, the taking ofsamples from locations where sediment or watercan collect, such as dead ends of piping, tankdrains, and low points of large pipes and filterbowls, should be avoided if possible. If samplesare taken from pipe drains, sufficient fluid shouldbe drained before the sample is taken to ensurethat the sample actually represents the system.Samples are not to be taken from the tops ofreservoirs or other locations where the contami-nation levels are normally low.3. Unless otherwise specified, a minimum ofone sample should be taken for each systemlocated wholly within one compartment. Forship’s systems extending into two or morecompartments, a second sample is required. Anexception to this requirement is submarineexternal hydraulic systems, which require only onesample. Original sample points should be labeledand the same sample points used for successivesampling. If possible, the following samplinglocations should be selected:a. A location that provides a samplerepresentative of fluid being suppliedto system componentsb. A return line as close to the supply tankas practical but upstream of any returnline filterc. For systems requiring a second sample,a location as far from the pump aspracticalOperation of the sampling point should notintroduce any significant amount of externalcontaminants into the collected fluid. Additionalinformation on hydraulic fluid sampling can befound in NAVAIR 01-1A-17.Most fluid samples are submitted to shorelaboratories for analysis. NAVAIR 17-15-50-1and NSTM, chapter 556, contain details oncollecting, labeling, and shipping samples.NAVAIR 01-1A-17 contains procedures forunit level, both aboard ship and ashore, testingof aviation hydraulic fluids for water, particulate,and chlorinated solvent contamination.3-11
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business