MIL-STD-1330-SUP-2 Precision Cleaning and Testing of Shipboard Oxygen, Helium, Helium-Oxygen, Nitrogen, and Hydrogen SystemsThis standard provides the requirements for precision cleaning and testing of oxygen or oxygen-enriched systems and components; oxygen generating plants including nitrogen, hydrogen, and demineralized water support systems and components; and helium, helium-oxygen, and hydrogen life support systems and components. Each activity will implement the applicable requirements of this document through a locally prepared and approved procedure. Activities subject to additional quality assurance requirements such as NAVSEA SS800-AG-MAN-010/P-9290 or NAVSEA SS521-AA-MAN-010 will obtain procedure approval from the applicable certifying activity.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 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 - 65 - 66 - 67 - 68 - 69 - 70 - 71 - 72 - 73 - 74 - 75 - 76 - 77 - 78 - 79 - 80 - 81 - 82

MIL-STD-1330D(SH)

20 September 1996

5.5.3.2 The following items shall be accomplished to prepare a system for flushing:

(a) Repairs to the piping system shall be completed before flushing is started.

(b) Valves, valve internals, pressure regulators, filter elements, or other mechanically jointed components that will interfere with the flow of the cleaning agent should be removed and flush plugs, spools, jumpers, and blanks shall be installed. Where jumpers are used, their inside diameter should be not less than the piping

they are bypassing. Seal welded regulators may be left in place if the high pressure chambers are disassembled and the nozzles removed.

(d) Components such as instruments which are not free draining shall be removed or isolated if appropriately configured. Cleanliness of certified oxygen clean instruments shall be maintained as

specified in 5.10.

(e) Flow restrictors, if installed in the supply nipple upstream of the

oxygen regulators, shall also be removed.

(f) Flushing rig, including temporary piping, components, and flush

plugs required for system flushing, shall be pressure tested and

cleaned to remove loose scale, dust, grit, filings, oil, and

grease.

5.5.3.3 All removed items shall be cleaned as specified in 5.2. Where it is necessary to flush with valve cartridges installed, after the flush, each

cartridge shall be removed and cleaned as specified in 5.2.

5.5.3.4 Large in-line volumes that will not support minimum flushing velocities should be individually cleaned and bypassed during the final flush if possible. The concern is that NOC and TSP final cleaners remove soil by displacement. In areas of low flow, suspended oil can separate from NOC or TSP and collect. If the volume cannot be bypassed, cannot be inspected and locally cleaned as specified in 5.12.4, and will collect separated oil perform the following: isolate the volume into the smallest flushing loop possible, obtain local engineering approval (see 6.3) to pre-clean by flushing with a low foaming detergent pre-cleaner that will emulsify oil contamination, and then perform the preflush as specified in 5.5.6 prior to the final NOC or TSP flush. The pre- cleaner is used to remove oil and grease contamination, and then NOC or TSP is used to remove any pre-cleaner residue and certify cleanliness. For volumes that cannot be bypassed, but can either be locally cleaned as specified in 5.12.4 or the configuration of the volume will not collect separated oil during the final

flush, such as an in-line vertically oriented flask, a separate pre-clean flush is not required.

5.5.4 Electrolytic oxygen gas generators. For systems with electrolytic oxygen generators, perform a potassium hydroxide (KOH) contamination inspection as specified in 5.6.

5.5.5 Leak-check. The flush boundary shall be leak-checked with nitrogen or grade B water to the anticipated flush pressure. This will eliminate the time consuming clean-up of spilled or leaked cleaner. Where an oxygen clean system interfaces with a flush boundary, using nitrogen for the leak check is

recommended. Any nitrogen leakage into the oxygen clean system will not cause loss of cleanliness.

5.5.6 Preflush. For new systems or systems with extensive modifications, a preflush as follows is recommended:

(a) Perform a forward and backward preflush at a minimum of 3 ft/sec using grade B water. The preflush water temperature may be elevated to not greater than 180EF. The higher temperatures will increase the effectiveness of the preflush and preheat the system minimizing the pipe line cleaning time.