1、I MIL-DTL-25666/7 (USAF) 15 September 1995 SUPERSEDING O1 April 1983 MIL-C-25674D (USAF) DETAIL SPECIFICATION CONVERTER LIQUID OXYGEN TYPE ME-3 This specification is approved for use by the Department of the Air Force and is available for use by ali Departments and Agencies of the Department of Defe
2、nse. 1. SCOPE 1.1 Scoue. This specification covers one type of liquid oxygen converter with a capacitance gauging element. It provides storage and pressurization of 25 liters of liquid oxygen to 300 pounds per square inch gauge (psig), nominal pressure and does not include warming coils. The convert
3、er is designated type ME-3. 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are needed to meet the requirements specified in sections 3, 4, and 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for
4、additional information or as examples. While evew effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements documents cited in sections 3,4, and 5 of this specification, whether or not they are listed. 2.2 Government doc
5、uments. 2.2.1 d tandards. The following specifications and standards form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department of Defense index for Specifications and Standards (DODISS) and s
6、upplement thereto, cited in the solicitation (see 6.2). SPECIFICATIONS DEPARTMENT OF DEFENSE MIL-V-9050 MIL-C-25516 MIL-DTL-25666 Valve, Oxygen, Aircraft, Pressure Relief Connectors, Electrical, Miniature, Coaxial, Environmental Resistant Type, Converter, Liquid Oxygen, Capacitance Type Gauging, Gen
7、eral Specification General Specification for For Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use improving this document should be addressed to: OC-ALCRICLA, 3001 Staff Eve, Tinker AFB, OK 73 145- 5990 by using the Standardization Document Impro
8、vement Proposal D Form 1426) appearing at the end of this document or by letter. AMSC NIA FSC 1660 DISTFUBUT ION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- flIL-DTL-Z5bbb/7 U
9、999Ob 2005343 552 m MIL-DTL-25666/7 STANDARDS DEPARTMENT OF DEFENSE MIL-STD- 129 Marking for Shipment and Storage (nless otherwise indicated, copies of federal and military specifications, and standards are available from the Standardization Documents Order Desk, Building 4D, 700 Robbins Ave, Philad
10、elphia, PA 191 11-5094) 2.3 Order of Precedence. In the event of a conflict between the text of this document and the references cited herein, the text of this documents takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has be
11、en obtained. 3. REQUIREMENTS 3.1 Oualification. Converters fiunished under this specification shall be products which are qualified for listing on the applicable qualified products list at the time set for opening of bids (See 4.2 and 6.3). 3.2 Besign. The converter shall conform to the dimensions a
12、nd general design shown on figures 1 and 2. The converter shall have a minimum capacity of 25 liters of liquid oxygen measured at 1 atmosphere plus at least 3 percent of this volume to allow for the change in liquid density at the operating pressure. The converter shall be designed for an operating
13、pressure of 300 psig. 3.2.1 Schematic Diagam. The converter shall be designed in accordance with the schematic diagram shown on figure 3. 3.2.2 Design streneth. The converter shall be designed to satis the dynamic force requirements specified in MIL-DTL-25666. When subjected to the acceleration test
14、, the following exceptions to the values for G levels shall apply: Vertical (down) 9G Vertical (up) 3G Lateral 4G 3.2.3 Relief valves. The relief valves shall conform to the performance requirements of types III and IV of MIL-V-9050 and shall be of such size and shape to fit the overall dimensions s
15、pecified for the converter. 3.2.4 Weight. The weight of the complete converter shall not exceed 38 pounds. 3 2.5 Marking of ports. Ports shall be marked as shown on figure 2. 3.2.6 Overpressure safety device. Safety discs or other secondary overpressure devices, as specified in MIL- DTL-25666 shall
16、not be required for this converter. The design of this converter incorporates two pressure relief valves. 3.3 Perform ance. 3.3.1 Final assemblv pressure. The pressure used for the final assembly pressure test shall be 320 psig. 3.3.2 Filling. Filling time shall not exceed 10 minutes when the conver
17、ter is tested as specified. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-DTL-25666/7 I 9999906 2005744 499 MIL-DTL-25666/7 3.3.3 Evaporation loss. 3.3.3.1 Vent condition. The evaporation loss of the essentially full converter in the vent co
18、ndition shall not exceed 4 pounds of oxygen when tested as specified in MIL-DTL-25666. 3.3.3.2 Buildup cond ition. The evaporation loss of the essentially full converter in the buildup condition shall not exceed 4 pounds of oxygen when tested as specified in MIL-DTL-25666. 3.3.4 BuilduD time. Buildu
19、p time shall not exceed 10 minutes when the converter is tested as specified in MIL-DTL-25666. 3.3.5 Capacitance. The capacitance of the sensing element of the empty converter shall be 303.5 k2.5 picofarad (pf) when tested as specified in MIL-DIL-25666. 3.3.6 Inner vessel pressure. 3.3.6.1 Inner ves
20、sel. The inner vessel shall meet the performance requirements for the inner vessel pressure test specified in MIL-DTL-25666 when subjected to a pressure of 500 psig. 3.3.6.2 Permanent volumetric expansion. The converter shall meet the performance requirements for permanent volumetric expansion as sp
21、ecified in MIL-DTL-25666 when subjected to a pneumatic or hydrostatic pressure of 500 psig . 3 3.7 Delivery rate. 3.3.7.1 Constant flow. The converter shall deliver a flow of gaseous oxygen up to 150 liters per minute for not less than 2 hours with the operating pressure remaining between 295 and 3
22、15 psig after the first 15 minutes of flow. The pressure shall be allowed to drop to 205 psig during the final 30 minutes of the 2 hour period. The flow at the specified rate shall be initiated within 10 minutes after the converter has reached the operating pressure. An intermittent increase or decr
23、ease of pressure by an additional 5 psig is allowable provided these variances do not exceed a 2 minute interval for any one pressure cycle. The full test procedure is specified in MIL-DTL-25666. 3.3.8 Calibration. The capacitance sensing element shall have characteristics which provide for a linear
24、 relationship between electrical capacitance and volume of liquid oxygen sensed. The relationship shall be as shown on figure 4, using either the equations or the referenced drawing to determine tolerances. An example of use of the equations is as follows: At the 10 - liter test point, suppose the a
25、ctual quantity of liquid oxygen is 10.1 liters. The measured capacitance must be between C maximum (max) and C minimum (min). C min = 5.715 x 10.1 + 300.5 = 358.2 pf C max = 5.875 x 10.1 + 306.5 = 365.8 pf 3.3.8.1 Eauations. The following equations shall be used to calculate the maximum and minimum
26、capacitances: Values less than 5 liters Values meater than 5 liters C min = 5.6L + 301.0 C rnax = 6.0L + 306.0 C min = 5.715L + 300.5 C max = 5.875L + 306.5 C = Capacitance in PF L = Exact quantity in liters of liquid at test point Provided by IHSNot for ResaleNo reproduction or networking permitted
27、 without license from IHS-,-,-MIL-DTL-25666/7 3.3.9 Operatinp temperature. The operating pressure shall remain between 295 and 320 psig after the first 15 minutes of flow at the low temperature and between 290 and 3 15 psig after the first 15 minutes of flow at the high temperature. An intermittent
28、increase or decrease of pressure by an additional 5 psig is allowable provided these variances do not exceed a 2-minute interval for any one pressure cycle. 3.3.10 -. 3.3.10.1 Vibration. The converter shall not exhibit physical evidence of damage after completion of the vibration tests as specified
29、in MIL-DTL-25666. 3.3.10.2 Vibration-. The converter shall not exhibit physical evidence of damage after completion of the resonance portion of the vibration test specified in MIL-DTL-25666. 3.3.10.3 Vibration - cvcling. The converter shall not exhibit physical evidence of damage after completion of
30、 the cycling portion of the vibration test specified (see 4.4.1). 4. VEIUFICATION 4.1 -. The inspection requirements specified herein are classified as follows: a. Qualification inspection (see 4.2) b. Conformance inspection (see 4.3). 4.2 Oualification inspection. The qualification inspection shall
31、 consist of all the inspection methods specified in MIL-DTL-25666. 4.3 i ection. The conformance inspection shall consist of the individual tests and the sampling plans and tests specified in MIL-DTL-25666. 4.4 Vibration. 4.4.1 Vibration - cycling. The converter shall be vibrated under the cycling c
32、onditions specified herein for the applicable periods listed in table I. The fiequency shall be cycled between 5 to 500 cps or as specified in the applicable associated specification and return in a 15 minute cycle at an applied double amplitude of 0.036 inch or an applied acceleration of +10G which
33、 ever is the lower G value. The rate of change of frequency shall be logarithmic (see 3.3.10.3). 5. PACKAGING 5.1 Packaging. Packaging requirements shall be as specified in the contract or order (see 6.2). 5.2 Marking. Unless otherwise specified (see 6.2), marking shall be in accordance with MIL-STD
34、-129. 6. NOTES. (This section contains information of a general or explanatory nature that may be helpful, but is not mandatory.) 6.1 Intended use. The 25 liter, 300 psig converter covered by this specification is intended for use on C-130, C-135, and (2-141 aircraft. 4 Provided by IHSNot for Resale
35、No reproduction or networking permitted without license from IHS-,-,-MIL-DTL-Z5bbb/7 999990b 200574b 2bL MIL-DTL-25666/7 6.2 Ordering: - data. Procurement documents should specify the following: a. Title, number and date of this specification. b. Issue of DODISS to be cited in the solicitation, and
36、if required, the specific issue of individual documents referenced (see 2.1). 6.3 Oualification. With respect to products requiring qualification, awards will be made only for products which are, at the time of award of contract, qualified for inclusion in Qualified Products List QPL 25666 whether o
37、r not such products have actually been so listed by that date. The attention of the contractors is called to these requirements, and manufacturers are urged to arrange to have the products that they propose to offer to the Federal Government tested for qualification in order that they may be eligibl
38、e to be awarded contracts or purchase orders for the products covered by this specification. information pertaining to qualification of products may be obtained from, OC-ALC/TICLA, 3001 Staff Drive, Tinker AFB, OK 73 145-3037. 6.4 Subject term fkev word! listing;. Breathing oxygen Capacitance Contai
39、ner, inner Container, outer Delivesr rate Dewar Element, sensing Evaporation loss Gunre Life support LOX Valve, fill-buildup-vent Valve, pressure closing Valve, pressure relief Vibration 6.5 ChanPes from Drevious issue. Asterisks are not used in this revision to identi changes with respect to the pr
40、evious issue, due to the extensiveness of the changes. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-VIL-DTL-Z5bbb/7 m 0b 2005747 LTB m MIL-DTL-25666/7 TABLE I. Ranve curve for converter vibration 30 6 Provided by IHSNot for ResaleNo reproduction
41、 or networking permitted without license from IHS-,-,-I I FIGURE 1. Converter asse mbiv 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-25666R . I FIGURE 2. Bottom view 8 Provided by IHSNot for ResaleNo reproduction or networking permitted
42、without license from IHS-,-,- MIL-DTL-25bbb/7 9999906 2005750 792 W MIL-DTL-25666L FIGURE 3. Schematic dhgrim 9 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- flIL-DTL-25bbb/ = 999990b 2005353 b29 - 5 10 15 20 25 MIL-DTL-25666/7 - 332.5 361.5 390.4
43、 4 19.4 448.4 Liquid oxygen (liters) I Nominal capacitance (pf) n 303.5 FIGURE 4. Relati* between cap acitance and volume of oxvgen sens& Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Custodian: Air Force - 99 Reviewer: Air Force - 11 MIL-DTL-25bbb/7 9999906 2005752 565 = MIL-DTL-25666/7 Frepariug Activity: Air Force -71 Agent: Air Force - 99 Project 1660-F687 11 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
