Tyco Electronics Corporation 300 Constitutional Drive Menlo Park, CA 94025 USA Specification This Issue: Date: Replaces: RT-1325 Issue 6 February 23, 2001 Issue 5 THERMOFIT(R) ELASTOMERIC MOLDED COMPONENTS Flame-Retarded, Semi-Rigid, Heat-Shrinkable 1. SCOPE This specification covers the requirements for one type of flexible, electrical insulating molded component whose expanded dimensions will reduce to a predetermined size upon the application of heat in excess of 175C (347F). 2. APPLICABLE DOCUMENTS This specification takes precedence over documents referenced herein. Unless otherwise specified, the latest issue of referenced documents applies. The following documents form a part of this specification to the extent specified herein. 2.1 2.2 GOVERNMENT-FURNISHED DOCUMENTS Federal P-C-437 Cleaning Compound, High Pressure (Steam) Cleaner VV-F-800 Diesel Fuel Military MIL-G-3056 MIL-T-5624 MIL-PRF-6083 MIL-A-8243 MIL-L-23699 MIL-H-46170 MIL-STD-105 Gasoline, Automotive, Combat Turbine Fuel, Aviation, Grades JP-4 and JP-5 Hydraulic Fluid, Petroleum Base, for Preservation and Operation Anti-Icing and Deicing-Defrosting Fluid Lubricating Oil, Aircraft Turbine Engines, Synthetic Base Hydraulic Fluid, Rust Inhibited Fire Resistant, Synthetic Hydrocarbon Base Sampling Procedures and Tables for Inspection by Attributes OTHER PUBLICATIONS American Society for Testing and Materials (ASTM) D 149 Standard Methods of Tests for Dielectric Breakdown Voltage and Dielectric Strength of Electrical Insulating Materials at Commercial Power Frequencies D 257 Standard Methods of Test for D-C Resistance or Conductance of Insulating Materials D 412 Standard Method of Tests for Rubber Properties in Tension D 570 Standard Methods of Test for Water Absorption of Plastics D 635 Standard Methods of Test for Rate of Burning and/or Extent and Time of Burning of SelfSupporting Plastics in a Horizontal Position D 792 Standard Methods of Test for Specific Gravity and Density of Plastics by Displacement D 2240 Standard Method of Tests for Rubber Property -- Durometer Hardness D 2671 Standard Methods of Testing Heat Shrinkable Tubing for Electrical Use G 21 Recommended Practice for Determining Resistance of Synthetic Polymeric Materials to Fungi If this document is printed it becomes uncontrolled. Check with the web for the latest revision. Page 2 SPECIFICATION RT-1325 ISSUE 6 (Copies of ASTM Publications may be obtained form the American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103.) 3. REQUIREMENTS 3.1 MATERIAL The molded components shall be fabricated from a crosslinked, thermally stabilized, flame-resistant, modified elastomeric composition. They shall be homogeneous and essentially free from flaws, defects, pinholes, bubbles, seams, cracks, and inclusions. 3.2 COLOR The molded components shall be black. 3.3 PROPERTIES The molded components and the material from which they are fabricated shall meet the requirements of Table 1. 4. QUALITY ASSURANCE PROVISIONS 4.1 CLASSIFICATION OF TESTS 4.1.1 Qualification Tests Qualification tests are those performed on molded slabs and components submitted for qualification as satisfactory products and shall consist of all tests listed in this specification. 4.1.2 Acceptance Tests Acceptance tests are those performed on molded slabs and components submitted for acceptance under contract. Acceptance tests shall consist of the following: dimensions, dimensional recovery, tensile strength, ultimate elongation, heat shock, and flammability. 4.2 SAMPLING INSTRUCTIONS 4.2.1 Qualification Test Samples Qualification test samples shall consist of six molded slabs, 6 x 6 x 0.075 0.010 inches (152 x 152 x 1.9 .25 mm) and the number of molded components specified. The molded slabs shall be fabricated from the same lot of material and shall be subjected to the same degree of crosslinking as the molded components. 4.2.2 Acceptance Test Samples Acceptance test samples shall consist of specimens cut from a molded slab 6 x 6 x 0.075 0.010 inches (152 x 152 x 1.9 .25 mm), and molded components selected at random in accordance with MIL-STD-105, inspection Level S-2, AQL 6.5 percent. The molded slab shall be fabricated from the same lot of material and shall be subjected to the same degree of crosslinking as the molded components. A lot of components shall consist of all molded components from the same lot of material, from the same production run, and offered for inspection at the same time. . If this document is printed it becomes uncontrolled. Check with the web for the latest revision. SPECIFICATION RT-1325 ISSUE 6 4.3 TEST PROCEDURES 4.3.1 Dimensional Recovery Page 3 Samples of molded components, as supplied, shall be measured for dimensions in accordance with ASTM D 2671. The samples then shall be conditioned for 10 minutes in a 175 2C (347 5F) oven, or equivalent, cooled to room temperature and re-measured. 4.3.2 Elastic Memory A 6 x 1/8-inch (152 x 3.2-mm) specimen cut from a molded slab shall be marked with two parallel gauge lines 1 inch (25 mm) apart in the central portion of the specimen. The distance between gauge lines shall be recorded as the original length. A 2-inch (51-mm) portion of the specimen including both gauge lines then shall be heated for 1 minute in a 175 2C (347 4F) oven, or equivalent, removed from the oven and stretched within 10 seconds, until the gauge lines are 4 inches (102 mm) apart. The extended specimen shall be cooled to room temperature and released from tension. After 24 hours at room temperature, the distance between the gauge lines shall be measured and recorded as the extended length. The portion of the specimen including both gauge lines then shall be reheated for 1 minute in a 175 2C (347 4F) oven, or equivalent, and the distance between gauge lines then shall be measured and recorded as the retracted length. Expansion and retraction shall be calculated as follows: E = Le - Lo x 100 Lo Le - Lr R = L - L x 100 e o Where: 4.3.3 E R Lo Le Lr = = = = = Expansion (percent) Retraction (percent) Original Length [inches (mm)] Extended Length [inches (mm)] Retracted Length [inches (mm)] Tensile Strength, Tensile Stress and Ultimate Elongation Three specimens cut from a molded slab using Die D of ASTM D 412 shall be tested for tensile strength, tensile stress and ultimate elongation in accordance with ASTM D 412. 4.3.4 Low Temperature Flexibility Three 6 x 1/4-inch (152 x 6.3-mm) specimens cut from a molded slab shall be conditioned, along with a 3/8inch (9.5-mm) mandrel, in a cold chamber at -55 2C (-67 4F) for 4 hours. After completion of the conditioning, and while still in the cold chamber, each specimen shall be bent around the mandrel through not less than 360 degrees within 10 2 seconds. The specimens then shall be visually examined for cracks. 4.3.5 Heat Shock Three 6 x 1/4-inch (152 x 6.3-mm) specimens cut from a molded slab shall be conditioned for 4 hours in a 225 5C (437 9F) mechanical convection oven with an air velocity of from 100 to If this document is printed it becomes uncontrolled. Check with the web for the latest revision. Page 4 SPECIFICATION RT-1325 ISSUE 6 200 feet per minute past the specimens. After conditioning, the specimens shall be removed from the oven, cooled to room temperature, and bent through 360 degrees over a 3/8-inch (9.5-mm) diameter mandrel. The specimens then shall be visually examined for evidence of dripping, flowing or cracking. 4.3.6 Heat Aging Three specimens, prepared and measured in accordance with 4.3.3 shall be conditioned for 168 hours in a 150 3C (302 5F) mechanical convection oven with an air velocity of 100 to 200 feet per minute past the specimens. After conditioning, the specimens shall be removed from the oven, cooled to room temperature, and tested for tensile strength and ultimate elongation in accordance with 4.3.3. 4.3.7 Fluid Resistance Six specimens prepared and measured in accordance with 4.3.3 shall be completely immersed in each of the test fluids listed in Table 1 for 24 hours at the temperature specified. The volume of the fluid shall be not less than 20 times that of the specimens. After conditioning, the specimens shall be lightly wiped and then air-dried for 30 to 60 minutes at 23 2C (73 4F) . The three specimens intended for the tensile strength and elongation tests shall then be tested for tensile strength and ultimate elongation in accordance with 4.3.3. The other three specimens shall be weighed before and after immersion and the weight change calculated as a percent. 4.4 REJECTION AND RETEST Failure of any sample to comply with any one of the requirements of this specification shall be cause for rejection of the lot represented. Material which has been rejected may be replaced or reworked to correct the defect and them resubmitted for acceptance. Before resubmitting, full particulars concerning the rejection and the action taken to correct the defect shall be furnished to the inspector. 5. PREPARATION FOR DELIVERY 5.1 PACKAGING Packaging of molded components shall be in accordance with good commercial practice. The shipping container shall be not less than 125 pound test fiberboard. 5.2 MARKING Each molded component shall be distinctly identified on the part and/or package with the manufacturing name or symbol, the manufacturer's part number, lot number, date of manufacture, and use before date. . 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SPECIFICATION RT-1325 ISSUE 6 Page 5 TABLE 1 Requirements PROPERTY PHYSICAL Dimensions UNIT REQUIREMENTS TEST METHOD Inches (mm) Section 4.3.1 ASTM D 2671 Dimensional Recovery Inches (mm) Elastic Memory Percent Tensile Strength Tensile Stress @100% Elongation Ultimate Elongation Specific Gravity Hardness Low Temperature Flexibility 4 hours at -55C (-67F) Heat Shock 4 hours at 225C (437F) Heat Aging 168 hours at 150C (302F) Followed by tests for: Tensile Strength Elongation ELECTRICAL Dielectric Strength psi (MPa) psi (MPa) Percent --Shore D In accordance with applicable specification control drawing In accordance with applicable specification control drawing 200 minimum expansion 90 minimum retraction 1500 minimum (10.3) 1500 maximum (10.3) 350 minimum 1.40 maximum 45 + 10 No cracking Volume Resistivity CHEMICAL Corrosive Effect 16 hours at 150C (302F) Flammability Average Time of Burning Average Extent of Burning Fungus Resistance Fluid Resistance 24 hours at 25 3C (77 5F) in: JP-4 Fuel (MIL-T-5624) Hydraulic Fluid (MIL-H-5606) Defrosting Fluid (MIL-A-8243) Lubricating Oil (MIL-L-23699) Cleaning Compound (P-C-437) Water Followed by tests for: Tensile Strength Ultimate Elongation Weight Increase Section 4.3.2 Section 4.3.3 ASTM D 412 ASTM D 792 ASTM D 2240 Section 4.3.4 --- No dripping, flowing or cracking Section 4.3.5 --- --- Section 4.3.6 psi (MPa) Percent 1200 minimum (8.3) 300 minimum Section 4.3.3 Volts/mil (kV/mm) ohm-cm 300 minimum (11.8) ASTM D 149 1012 minimum ASTM D 257 --- Noncorrosive Section 4.3.7 ASTM D 2671 Procedure A Seconds Inches (mm) ----- 120 maximum 1.0 maximum (25) Rating of 1 or less --- ASTM D 635 psi (MPa) percent percent 1000 minimum (6.9) 200 minimum 8 maximum If this document is printed it becomes uncontrolled. Check with the web for the latest revision. ASTM G 21 Section 4.3.8 Section 4.3.3 Section 4.3.8 Page 6 SPECIFICATION RT-1325 ISSUE 6 TABLE 1 Requirements CHEMICAL (Continued) Fluid Resistance 24 hours at 50 3C (122 5F) in: DF-2 (VV-F-800) JP-4 Fuel (MIL-T-5624) Followed by tests for: Tensile Strength Ultimate Elongation Weight Increase Fluid Resistance 24 hours at 71 3C (160 5F) in: Hydraulic Fluid (MIL-PRF-6083) Hydraulic Fluid (MIL-H-46170) Followed by tests for: Tensile Strength Ultimate Elongation Weight Increase --- --- Section 4.3.8 psi (MPa) percent percent --- 1000 minimum (6.9) 200 minimum 15 maximum --- Section 4.3.3 psi (MPa) percent percent 1000 minimum (6.9) 200 minimum 25 maximum . If this document is printed it becomes uncontrolled. Check with the web for the latest revision. Section 4.3.8 Section 4.3.8 Section 4.3.3 Section 4.3.8