1、 flIL-STD-Lb07A qq = 9977933 003Lib47 5 E 2 O AMSC N/A MIL-STD-l607A(SH) 11 August 1987 SUPERSEDING MIL-STD- 1607 (SHIPS) 30 March 1973 (See 4.15) MILITARY STANDARD CHEMICAL CLEANING OF MAIN AND AUXILIARY BOILERS (SULFAMIC-CITRIC ACID METHOD) . FSC 4410 DISTRIBUTION STATEMENT A Approved for public r
2、elease; distribution unlimited THIS DOCUMENT CONTAINS i7 PAGES. - Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-r.1 r L- sru - 160 78 (sir) 11 August 1387 DEPAKTPIENT OF THE NAVY NAVAL SEA SYSTEMS CONPIAND Washington, DC 20362-5101 Clicmieal Cleani
3、ng of Plain and Auxiliary Boilers (Sulfamic-Citric Acid Method), 1. This Pilitary Standard is approved for use by the Naval Sea Systems Command, Department of the Navy, and is available for use by all Departments and Agencies o the Department of Defense. 2. Beneficial comments (recommendations, addi
4、tions, deletions) and any perti- nent data which may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 5523, Department of the Navy, Washington, DC 20362-5101 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426)
5、 appearing at the end of this document or by letter. ii Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD-3607A 44 M 7777733 0034647 7 M NIL- STD - 160 7A (SH) 11 August 1987 Paragraph 1. 1.1 1.2 2. 2.1 2.1.1 2.1.2 2.2 3. 4. 4.1 4.2 4.3 4.4 4.5
6、 4.6 4.7 4.7.1 4.7.2 4.7.3 4.8 4.9 4.10 4.11 4.12 4.12.1 4.12.2 4.12.3 4.12.4 4.13 4.14 4.15 F, and Associated Parts; MIL-F-16377/51 - Fixtures, Lighting; Incandescent, Light Exten- Shipboard Use, General Specification for. sion 25 Watts, 120 Volts, Explosionproof and Watertight, Symbols 290 and 291
7、. MIL-R- 19 180 - Regulators, Pressure, Compressed Gas. MIL - P - 24 13 8 - Passivator Compound, Navy Boiler. MIL- B - 24 15 5 - Boiler Scale Removing Compound. MIL -H - 2 9 2 10 - Hose Assembly, Rubber, Metal Lined, Wire Reinforced, 250 PSIG, Saturated and Super- heated Stream Service. 1 Provided b
8、y IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MLL-STD-Eb07A L(L( pi 9q991L 034b5L 7 STANDARDS FEDERAL FED-STD-595 - PIILITARY Pl I L-STD - 7 9 6 Colors. Chemical Cleaning of Plain and Auxiliary Boilers (Hydrochloric Acid Method) . 2.1.2 Government publicatio
9、ns. The following Government publications form a part of this standard to the extent specified herein. PUBLICATIONS NAVAL SEA SYSTEMS COPfMAND (NAVSEA) S9086-GY-STFl-O00/CH 221 - NSTM, Boilers. S9086-GX-STFl-O20/CH 220 V2 - NSTH, Boiler Water/Feedwater Test S9086-T8-STPl-O00/CH 533 - NSTM, Pollution
10、 Control. and Treatment. (Copies of specifications, standards, and publications required by contrac- tors in connection with specific-acquisition functions should be obtained from the contracting activity or as directed by the contracting officer.) 2.2 Order of precedence. In the event of a conflict
11、 between the text of this standard and the references cited herein, the text of this standard shall take precedence. 3. DEFINITIONS Not applicable. 4, GENERAL REQUIREPlENTS 4.1 Mill scale and waterside deposit removal. This procedure shall be used in the removal of mill scale from new boilers prior
12、to final contract accept- ance trials as well as for removal of waterside deposits that may be found in boilers after extensive operation. This cleaning method is not effective in the removal of waterside deposits containing more than 5 percent silicates or 10 percent sulfates. 4.2 Utilities availab
13、le. The following utilities are normally available at doeksido: (a) Fresh water. (b) (c) (d) Electrical power. Steam at 100 pounds per square inch (lb/in2), Compressed air at 90 to 100 lb/in2. 4.3 Solution disposal This specification provides procedures for neutralizing the solutions used for cleani
14、ng, rinsing and pocsivating. Ship- board neutralizing of these solutions may not be required.- All solutions shall be disposed in accordance with local, state and federal regulations (see NAVSEA S9086-T8-STM-OO/CH 593). 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without l
15、icense from IHS-,-,-MIL-STD-Lb07A LiLi m 7797712 0034b52 7 m ?lIL- SY11 - 1GO 711 (Sir) 11 August 1387 4.4 Equipment Tor acid descaling. Personnel shall read and be thoroughly familiar with the safety requirements specified in 4.12 before proceeding with tlic cleaning operation. The following equipm
16、ent shall be required: An acid mixing tank as shown on figure 1 or equal and a spent acid neutralizing tank with an approximate capacity of 1500 gallons. An acid pump capable of recirculating 50 gallons per minute (gal/min) but not more than 100 gal/min against a 50-foot head. Steam generator or equ
17、ivalent for heating solutions to required temperatures (not required if 100 lb/in2 steam is available). Water treatment equipment to provide water of feedwater quality or water having hardness values less than 50 parts per million (p/m) as calcium carbonate (not required if water meeting these requi
18、rements is available). pH test paper indicator strips having a pH range from 2 to 10. Indicator test strips are available from Fischer Scientific, Springfield, New Jersey. 500 feet of 1-1/2 inch acid hose for admitting solutions to boilers (rated at 150 lb/in2). Hypalyne acid and chemical hose serie
19、s 7267 available from Dayco Industries, Dayton, Ohio or equal is an acceptable hose for the applicaion. for hydrogen vent lines. Flexible metallic steam hose meeting the requirements of NIL-H-29210. Assorted hoses for air, nitrogen, and water supply as well as Explosimeter (Mine Safety Appliances ,
20、Model 3 or equal). Portable pyrometer (Alnor Pyrocon or equal). Assorted thermometers. Assorted nonsparking tools, including hammers, wrenches, and screw- Portable, watertight, vaporproof lights (see 4.12.3.3). Equipment that is normally required for hydrochloric acid cleaning drivers. Also tools fo
21、r repairing acid cleaning equipment. may also be used. 4.5 Chemicals required. Chemicals employed in this cleaning procedure are either in crystal line or flaked form and shall be dissolved in hot water that is being recirculated through the mixing tank and the boiler. Chemicals used to neutralize t
22、he partially spent descalant shall be dissolved in water in the neutralizing tank. Chemicals and quantities required for descaling, passivating, and neutralizing shall be as follows: (a) Boiler scale removing compound shall be in accordance with MIL-B-24155 and prepared in the following quantities r
23、equired to fill the boiler to air cock: (1) For descalant (strong solution), 1000 pounds of boiler scale removing compound per 1000 gallons of water. (2) For acid rinse (mild solution), 20 pounds of boiler scale removing compound per 1000 gallons of water. (b) Passivator compound shall be in accorda
24、nce with MIL-P-24138 and the solution shall be prepared with 84 pounds of passivator compound per 1000 gallons of water required to fill the boiler to air cock. Only feedwater or water with a hardness value of 50 p/m or less as calcium carbonate shall be used for the pas- sivating solution. 3 Provid
25、ed by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD-1607A 44 W 9999911 0034b53 O U NIL-STD - 160 7A (SI) 11 August 1967 (c) Sodium hydroxide (caustic soda) shall be in accordance with type I of 0-5-538. pounds of sodium hydroxide (to be dissolved in 70
26、0 gallons of cold water) to neutralize 1000 gallons of spent acid solution. class 1 of BB-N-411. Nitrogen cylinders shall be fitted with regulators in accordance with type II, class B2-W of WIL-R-19180. 27886 of FED-STD-595) shall be in accordance with TT-E-490. of 8-S-511. The solution shall be pre
27、pared with 200 (d) Nitrogen (oil free) shall be in accordance with type I, grade Cy (e) Exterior enamel, silicone alkyd copolymer, semigloss (color no. (f) Sodium carbonate, anhydrous shall be in accordance with type I 4.6 Preparation of boiler and equipment. Due to differences in boiler configurati
28、ons, auxiliary boilers and waste heat boilers shall have those requirements for main propulsion boilers eliminated which are not applicable to auxiliary or waste heat boilers. Preparation of the boiler and equipment shall be as specified as follows (see figure 2): (a) Valves controlling admission of
29、 water or steam to the unit to be cleaned (boiler, economizer, superheater, auxiliary boiler or waste heat boiler) shall be closed, tagged and locked (or security wired). Gauges, valves and fittings that are not to be employed during cleaning of the unit shall be blanked off. Any nonferrous valves,
30、fittings or trim components shall be removed and their connections blanked. System valves shall not be used for blanking purposes and shall be isolated from the acid. Safety valves shall be removed and the openings shall be blanked. One blank shall be provided with a 1-1/2 inch ripple. (b) The boile
31、r shall be drained and opened. Watersides shall be inspected for oil contamination or preservative coatings and, if present, shall be analyzed to determine quantity. If the amount of organic contaminants found are greater than 3 percent of the waterside deposits, a boil-out shall be applied. The pro
32、cedure in accordance with NAVSEA S9086-GY-STM-O00/CH 221 shall be utilized for removing the organics. solution shall be disposed in accordance with 4.5. first row furnace side of each boiler to be cleaned. Removal shall be from an area about 1/2 to 2/3 of the furnace depth. The tubes shall be replac
33、ed or the tube seat holes plugged. Two 30-inch sections shall be cut from the mud drum part of the removed tube. These sections shall be hung securely, in a vertical position, in the steam drum. These tubes will provide a means for assessment of the effectiveness of the cleaning operation. The remai
34、nder of the tube shall be reserved for: future reference. from new, unsteamed boilers or from new boilers that have loose deposits such as those to be cleaned immediately after the completion of acceptance trials. the effectiveness of the cleaning shall be as specified in 4.11.3. time shall the desu
35、perheaters be pickled. inlet and outlet connections shall be blanked in the boiler to prevent acid leakage into these nipples. (Rubber gaskets shall The boil-out (e) A screen tube, not recently installed, shall be removed from the It shall not be necessary to remove a tube The method for determining
36、 (d) Desuperheaters shall be removed and cleaned mechanically. At no The desuperheater 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD-Lb07A 94 m 7777733 003965i1 2 m MIL-STD-l6078(SH) 11 August 1987 be used.) The inlet and outlet desuperhe
37、ater nipples (in the boilers) shall be coated with exterior semigloss enamel, silicone alkyd copolymer (color no. 27886 of FED-SSD-595) in accordance with TT-E-490. The nozzles shall be wire brushed to remove adhering deposits. A single coat of enamel shall be applied and allowed to dry for 2 hours.
38、 After the cleaning operation, the enamel shall be removed from the nipples and other parts of the boiler watersides by wire brushing or chipping. (e) At least two steam separators and all girth plates shall be removed and left in the drum so as not to cover the tubes. (f) If inspection reveals that
39、 cleaning of the economizer and superheater is not required, the economizer and superheater shall be back filled with feedwater and these units shall be blanked off. off as shown on figure 2. A blank shall be installed at the economizer inlet to isolate the economizer from the feed system. proper is
40、olation. Blanks shall be placed on both sides of the check valve at the economizer outlet. Blanking both sides of the check valve prevents acid damage to the check valve. The superheater inlet shall be blanked at the steam drum using the acid wash plug. The superheater outlet shall be blanked at the
41、 closest possible location to the superheater outlet header. A closed main stop valve is not considered satisfactory for proper isolation. be cleaned while blanked from the boiler as specified in 4 (f). cleaning, only the economizer and boiler shall be cleaned simultaneously. using fresh descalant.
42、economizer shall not be used to clean the superheater. (i) During superheater cleanings, two or three water rinses shall be applied following the strong acid treatment. The presence of acid shall be determined using the pH test paper indicator strips. The water rinses shall be used instead of the mi
43、ld acid rinse and passivating step to eliminate the possibility of acid or passivator remaining in the superheater. side. The hydrogen vent hose shall be attached to one of the valves and shall lead to the weather deck or pier. The hose shall not be crimped or obstructed in any way to prevent escape
44、 to the evolving hydrogen gas. A length of copper tubing or hose (capable of withstanding a pressure of 100 lb/in2) shall be connected from the nitrogen supply to the valve on the other side of the tee. (k) A 1-1/2 inch valve shall be attached to the safety valve blank flange on top of the boiler. T
45、he 1-1/2 inch acid resistant discharge hose shall be connected to the nipple on this valve and the line shall be led back to the mixing tank to permit recirculation of the descaling solution. (i) Bottom blow valves shall be disconnected from the boiler and a temporary valve manifold shall be install
46、ed as shown on figure 2. At one end of the manifold, a tee shall be installed with The economizer and superheater shall be blanked A closed feed valve is not considered satisfactory for (g) It the economizer and superheater require cleaning, they shall (h) If the boiler economizer and superheater al
47、l require acid The superheater shall be cleaned separate y Descalant used to clean the boiler and (j) A tee shall be attached to the air cock, with valves on each 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. i-l/Z iiicli valves attciclicd to e
48、nch side to permit altcriiate iritrodiictioii of stcam or acid into tlie boiler. A sclicinntic diagram of the pipiiig sntiip is sliown on figure 2. descalant is injected into the lowest point of the system aiid is returned from the highest available opening on the uiiit. or a weather deck compatible
49、 with minimal hose requirements. The 1500-gallon iieiitralizing taiik shall be located in ali area easily accessible for receiving the spent acid from the boiler to permit neutralization of the descalant prior to disposal. The acid fill line shown on figure 2 shall later serve as the acid disposal line. The lines shall be kept to minimal lengths. Economizer and superheaters that are not to be acid cleaned shall be kept filled with wat
