S9407-AB-HBK-010 Datasheet, PDF (226/276 Pages) Glenair, Inc. – HANDBOOK OF SHIPBOARD ELECTROMAGNETIC SHIELDING PRACTICES

S9407-AB-HBK-010, Rev. 2
4.6.7 Shielding effectiveness. After completion of the bend-radius test of 4.6.6, the sample, with
braid ends brazed to the tubing as in 3.6.8, shall be subjected to two bend cycles, where one bend
cycle entails bending the center section through a 90-degree arc over the mandrel of 4.6.6,
straightening it, bending the center section 90 degrees in the opposite direction over the same
mandrel and straightening it to complete the cycle. The sample shall then be tested for effectiveness
of shielding against a transverse magnetic field having a field intensity of 1 oersted over the frequency
range of 30 Hz to 30 kHz. The test method shall be in accordance with ANSI/ASTM-A-698, with the
following exceptions:
a. The inside diameter of each Helmholtz coil section shall be 35cm.
b. The center section of the conduit shall be symmetrically positioned between coil
sections with its axis in the plane of the coils and with its ends extending out
straight and beyond the coil sections.
c. The pickup coil shall be designed to fit inside the long tubular shape of the conduit.
The coil shall provide an adequate signal over the frequency range 30 Hz to 30
kHz. Figure 4 shows the design of such a coil with typical dimensions suitable for
use with conduit as small as 1/4-inch size.
Note: Particular care should be taken to maintain the plane of the pickup parallel to the
planes of the helmholtz coil sections. Steel end caps may be required on the test
sample (particularly on the larger sizes) to preclude flux leakage into the open
ends of the conduit.
4.7 Test reports. The supplier shall prepare a test report for each production lot (see 4.5.1). The
test report shall include the following: the production lot number, a certification of materials inspection
(see 4.3) which applies to the production lot, a certification that all of the conduit in the production lot is
identical to a qualified test sample (see 4.4), and certification that each of the quality conformance
inspections of 4.5 has been performed and any conduit that is defective, or fails to meet requirements,
has been either corrected or rejected. All test reports shall be retained on file by the manufacturer of
the conduit and shall be available for review for a period of 2 years following product fabrication. Test
reports, in duplicate shall be furnished when required by the contract or order (see 6.2).
4.8 Quality assurance. All conduit manufactured under this specification shall be identical to
qualified test samples. The conduit shall be subject to DCAS (Defense Contract Administration
Service) inspection at source of shipment when specified by the contract or order (see 6.2).
5. PACKAGING
5.1 Cleaning. Any conduit produced to this specification shall be manufactured under processes
which have sufficient quality control procedures to prevent contamination. However, and conduit not
meeting the cleanliness requirement of 3.6.4 can be processed in accordance with MIL-P-116 process
C1 in order to meet the requirements of 3.6.4. Any drying procedure shall not be injurious to the
finished product.
CHANGE 1 of Revision 2
D-12