1、 MIL-DTL-26666G 10 December 2006 SUPERSEDING MIL-DTL-26666F 23 April 2004 DETAIL SPECIFICATION HOSE ASSEMBLY, PNEUMATIC, HIGH PRESSURE This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers the requirements f
2、or a hose assembly, pneumatic, high pressure having a nominal working pressure of 4,000 psig (275.79 bar) in the operating temperature range of -65 to +160F (-53.89C to 71.11C). DO NOT USE FOR OXYGEN. DO NOT USE ON AIRCRAFT. 1.2 Part or Identifying Number (PIN). The definitive specification PIN will
3、 be formatted to identify each item covered by this specification. The PIN format will consist of the letter M, specification number, a dash, a 2 digit number hose size, a dash and a 2 digit fitting size, a dash and 2 a digit fitting size, a dash hose assembly length in inches (3 digits), fourth dig
4、it in 8s of an inch (0 through 7), and coupling guard “A” (as required) as follows: M26666 -04 -04 -06 -0753 AComments, suggestions, or questions on this document should be addressed to: Defense Supply Center, Columbus, Attn: DSCC-VAI, P.O. Box 3990, Columbus, OH 43218-3990, or emailed to Constructi
5、ondscc.dla.mil. Since contact information can change, of this address information using the ASSIST Online database at INCH-POUND AMSC N/A you may want to verify the currency http:/assist.daps.dla.mil. Specification number M prefix Fitting guard (see 3.3.2.5) (Required add “A” - not required leave bl
6、ank) Hose assembly length. First 3 digits in inches, fourth digit in 8s of an inch (0 through 7) Fitting size dash number from figure 1. (Jump size see 3.3.2.4) Fitting size dash number from figure 1. (Jump size see 3.3.2.4) Hose size dash number from figure 1. FSC 4720MIL-DTL-26666G 2 2. APPLICABLE
7、 DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to
8、 ensure the completeness of this list, document users are cautioned that they must meet all specified requirements documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following spe
9、cifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issue of these documents are those cited in the solicitation or contract. DEPARTMENT OF DEFENSE STANDARD MIL-STD-889 - Dissimilar Metals (Copies of these documents are a
10、vailable online at http:/assist.daps.dla.mil/quicksearch/ or http:/assist.daps.dla.mil or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.3 Non-Government publications. The following documents form a part of this document to the extent s
11、pecified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. ASTM INTERNATIONAL ASTM D1248 - Polyethylene Plastics Extrusion Materials for Wire and Cable ASTM D2000 - Rubber Products in Automotive Applications (Copies of these documents
12、are available online at http:/www.astm.org or from the ASTM International, P.O. Box C700, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.) SAE INTERNATIONAL SAE AMS 2700 - Passivation of Corrosion Resistant Steels SAE ARP908 - Hose and Tube Fitting, Installation and Qualification Test Torqu
13、e Requirements SAE AS4395 - Tube Connection, Fitting End-Flared, Design Standard SAE AS5175 - Nut, Coupling, Flared SAE AS8879 - Screw Threads, Controlled Radius Root with Increased Minor Diameter, General Specification for (Copies of these documents are available online at http:/www.sae.org or from
14、 the SAE World Headquarters, 400 Commonwealth Drive, Warrendale, PA 15096-0001.) 2.4 Order of precedence. In the event of a conflict between this text of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicabl
15、e laws and regulations unless a specific exemption has been obtained. MIL-DTL-26666G 3 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), samples shall be subjected to first article inspection in accordance with 4.5. 3.2 Materials. Materials shall be as identified herein or as approved by
16、the acquiring activity. However, when a specific material is not specified, a material shall be used which will enable the hose assemblies to meet the performance requirements of this specification. Acceptance or approval of any constituent material shall not be construed as a guarantee of acceptanc
17、e of the finished product. 3.2.1 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent possible provided that the material meets or exceeds the operational and maintenance requirements, and prom
18、otes economically advantageous life cycle costs. 3.2.2 Hazardous substances. The use of hazardous substances, toxic chemicals, or ozone depleting chemicals shall be avoided, whenever feasible. 3.2.3 Other materials. Materials not otherwise specified shall be in accordance with applicable specificati
19、ons and to the requirements specified herein. All materials that are not specifically described shall be of the highest quality and suitable for the purpose intended. 3.2.4 Fungus proof materials. Materials which are not nutrients for fungi shall be used to the greatest extent practicable without ef
20、fecting performance. Where materials that are nutrients for fungi must be used, such materials shall be treated with a fungicidal agent to render the material fungus-resistant. 3.2.5 Rubber products. Rubber products, such as, seals, covers, and friction layers shall be fabricated from rubber compone
21、nts in accordance with ASTM D2000. 3.2.6 Dissimilar metal. Unless protected against electrolytic corrosion, dissimilar metals shall not be used in intimate contact with each other. Dissimilar metals are defined in MIL-STD-889. 3.3 Design and construction. The hose assembly shall be designed for a pn
22、eumatic working pressure of 4,000 psig (275.79 bar) in an operating temperature range of -65F to +160F (-53.89C to 71.11C). 3.3.1 Hose construction. The hose assembly shall consist of a hose with a seamless inner tube, reinforced with corrosion resistant steel wire coupled with corrosion resistant s
23、teel end fittings, and a protective outer cover. The hose shall be capable of retaining end fittings without slippage or leakage. 3.3.1.1 Inner tube. The inner tube shall consist of a high density polyethylene compound of seamless construction and uniform gage. It shall be compounded and processed t
24、o permit the least amount of effusion of compressed gases consistent with the requirements specified herein. The uncompounded polyethylene material shall conform to ASTM D1248, type 3. The inner tube shall have a smooth bore, be free from pitting and other defects, and free of any foreign material o
25、r lubricants. 3.3.1.2 Reinforcement. The reinforcement shall consist of two or more spirally wrapped or braided (or combination there-of) plies of high tensile steel wires. Reinforcement separation materials, if used, shall permit gas effusion from the inner tube to escape to the atmosphere. There s
26、hall be no broken or spliced reinforcing wires nor shall any wires be omitted in any length of hose. MIL-DTL-26666G 4 3.3.1.3 Outer protective cover. An outer protective cover extending the full length of the hose, .125 to .250 inch (3.18 to 6.35 mm) from the end of the fitting, shall be furnished o
27、n the outside of the hose. The cover shall be a minimum of .0625 inch (1.588 mm) thick, consist of an abrasion-resistant, oil-resistant, and ozone-resistant chloroprene polymer or equivalent synthetic material compounded to meet the requirements specified herein. The cover need not be bonded to the
28、outer-most reinforcement ply, but shall not be free to slip or turn along the length of hose. The cover shall permit gas that may effuse from the inner tube to escape to the atmosphere. 3.3.2 Hose assembly configuration. The hose assembly shall meet the requirements as specified herein. 3.3.2.1 Diam
29、eter. The inside and outside diameters of the hose shall be within the limits shown on figure 1 as applicable to the hose size specified by the acquiring activity (see 1.2). 3.3.2.2 Length of hose assembly. The hose assembly shall be furnished in lengths as specified by the acquiring activity (see 1
30、.2). The hose assembly length shall be measured as shown on figure 1. Hose size and fitting size designator Tube ID A hose ID min (mm) B hose OD max (mm) C coupling ID min (mm) D (max) (mm) E (mm) F (dia) (max) (mm) Hose min. inside bend rad (mm) 04 1/4 .234 (5.94) .703 (17.86) .125 (3.18) 2.100 (53
31、.34) .375 (9.53) .875 (22.23) 3.250 (82.55) 06 3/8 .297 (7.54) .859 (21.82) .188 (4.78) 2.470 (62.74) .375 (9.53) 1.160 (29.46) 5.250 (133.35) 08 1/2 .422 (10.72) 1.000 (25.40) .297 (7.54) 2.730 (69.34) .438 (11.13) .015 (0.38) 1.375 (9.53) 6.000 (152.40) 10 5/8 .547 (13.89) 1.218 (30.94) .391 (9.93
32、) 3.020 (76.71) .515 (13.08) 1.550 (39.37) 6.750 (171.45) 12 3/4 .672 (17.07) 1.375 (34.93) 0.547 (13.89) 3.230 (82.04) .602 (15.29) .031 (0.79) 1.740 (44.20) 8.000 (203.20) NOTES: 1. Dimensions are in inches. 2. Metric equivalents are for information only. 3. Length “L” shall be within +3% or -1% o
33、f specified nominal value. 4. Provisions for wrenching by a hex or flats on fitting body shall be optional. FIGURE 1. Hose assembly details. MIL-DTL-26666G 5 3.3.2.3 End fittings. The hose assembly end fittings shall conform to the general configuration shown on figure 1. The end fittings shall be r
34、etained on the assembly without slipping or leaking when coupled to the hose and tested as specified herein. The fittings shall be made of corrosion resistant steel and shall be passivated in accordance with SAE AMS 2700 method 1,class 2. The hose assembly end fittings shall mate with fittings accor
35、dance with SAE AS4395 corresponding to the hose size. 3.3.2.3.1 Swivel nuts. The swivel nut dimensions across flats shall conform to an applicable size of SAE AS5175. The nipple bore diameter shall conform to the limits shown on figure 1. 3.3.2.3.2 End fittings working pressure. The end fitting shal
36、l be designed for a working pressure of 4,000 psig (275.79 bar) and a minimum burst pressure of 16,000 psig (1103.16 bar). 3.3.2.4 Jump sizes. When specified (see 1.2), the hose assembly shall be supplied with an end fitting(s) of a different nominal size than the hose itself. In such cases, the end
37、 fitting swivel nut and nipple shall mate with fittings accordance with SAE AS4395 for the specified jump size while the fitting body and nipple bore diameter shall conform to the applicable dimensions for the specified nominal hose size (see figure 1). 3.3.2.5 Fitting guard. When specified (see 1.2
38、 and 6.2.h) a fitting guard shall be securely attached to each end of the hose assembly to restrict the hose bend angle at the fitting. The fitting guard shall have less flexibility than the hose and encase the ends of the hose and fitting. 3.3.3 Finish. Unless otherwise specified, all corrosion-res
39、istant steel fitting components shall be passivated in accordance with SAE AMS 2700 prior to assembly. Parts shall then be thoroughly rinsed in water and dried. 3.4 Screw threads. All coupling nut threads shall be in accordance with SAE AS8879. 3.5 Performance. 3.5.1 Visual examination and dimension
40、al check. 3.5.1.1 Visual examination. The hose assembly shall conform to the requirements of this specification when visually examined as specified in 4.7.1.1. 3.5.1.2 Dimensional check. The hose assembly shall be in accordance with figure 1 when dimensionally checked in accordance with 4.7.1.2. 3.5
41、.2 Proof pressure. The hose assembly shall not show any evidence of leakage, distortion or material failure, when tested in accordance with 4.7.2. 3.5.3 Leakage. The hose assembly shall not leak when subjected to a pneumatic pressure of 4,000 psig (275.79 bar), when tested in accordance with 4.7.3.
42、3.5.4 Cold temperature flexing. The hose assembly shall not show any evidence cracking, splitting, distortion, or leakage when tested in accordance with 4.7.4. 3.5.5 Elongation and contraction. The change in hose length shall be within 3 percent, when tested in accordance with 4.7.5. 3.5.6 Tensile s
43、trength. The hose assembly shall not show any evidence of material failure from a tensile pull of not less than 1,000 pounds (453.59 kg), when tested in accordance with 4.7.6. MIL-DTL-26666G 6 3.5.7 Burst pressure. The hose assembly shall not burst or show any evidence of material failure when teste
44、d in accordance with 4.7.7. 3.5.8 Overtightening torque. The end fitting of the hose assembly shall not show any evidence of material failure, thread damage, deformation or difficulty in turning the swivel nut on the nipple by hand, when tested in accordance with 4.7.8 3.5.9 Pressure impulse cycling
45、 (see 4.7.9). 3.5.9.1 Ambient temperature pressure impulse cycling (see 4.7.9.1). The hose assembly when tested in accordance with 4.7.9.1 shall not show any evidence of cracking, splitting, distortion, or leakage. 3.5.9.2 Elevated temperature pressure impulse cycling (see 4.7.9.2). The hose assembl
46、y when tested in accordance with 4.7.9.2 shall not show any evidence of cracking, splitting, distortion, or leakage. 3.5.10 Cleanliness. All hose assemblies shall be free from oil, grease, dirt, moisture, cleaning solvents and other foreign material, both internally and externally. The hose assembly
47、 shall not contain any particle size larger than 30 microns or a total residue weight greater than one milligram per milliliter of the measured fluid sample, when tested in accordance with 4.7.10. 3.6 Identification of product. The hose assembly shall be identified by a permanently snug-fitting alum
48、inum or stainless steel band around the hose near the end fitting. The band shall be designed to remain tight on the hose to prevent relative movement and resultant chafing. Where the hose assembly exceeds 4 feet (1.22 m) in length, a band shall be attached near each end fitting of the assembly. The
49、 metal band shall be marked in raised, etched, or stamped lettering with the following information appropriately identified: a. Number and title of this specification. b. DO NOT USE ON AIRCRAFT c. Date of assembly in month and year. d. The rated working pressure in psig, followed by the word PNEUMATIC. e. Manufacturers name and trademark. f. PIN (see 1.2). g. Hose manufacturers cage code if different from hose assembly manufacturer. 3.7 Pre-packaging. Immediately after cleaning the hose assembly the end fittings on both ends of the hose shall be capped or plugged. The hose
