BS/EN 3275-2019 pdf download.Aerospace series – Pipe coupling 8°30’ up to 28 000 kPa – Dynamic beam seal -Metric series – Technical specification.
5.1 Test conditions and preparation of specimens for qualification Tests fluids
Unless otherwise specitied, tests shall be carried out using e.g. a petroleum base hydraulic fluid to MIL-H-5606 for coupling assemblies of type II temperature range and a silicate ester base hydraulic fluid to MIL-H-8446 for those of type Ill temperature range. Water may be used, whenever practical, for proof, burst, stress corrosion and re-use capability testing. For other than hydraulic system applications, it Is preferable to use system fluid for leakage (gaseous pressure) and proof testing. When specified in the test method, the test fluid is used as a lubricant.
Specimen preparation
Shaped parts shall be machined with the grain flow of the bar or plate in the direction of the fluid. Specimens shall be assembled as illustrated in Table 2. Installations on the pipe end shall be in accordance with TR 2674. Prior to testing, all couplings shall be assembled using the maximum specified torque. Except, when specified in Table 2, the coupling shall be assembled using the minimum installation torque for at least half of the specimens, and maximum torques for the remainder.
Pipe assembly
The method of joining the pipe to the coupling end (brazing, welding, mechanical attachment, etc.) shall not be detrimental to the properties, strength or geometry of the pipe and the coupling end. The joint shall be in accordance with the design instructions and shall be inspected by direct measurement, X-ray or other non-destructive methods.
6.1 Product qualification
The qualification procedure for aerospace standard products (e.g. according to EN 9133 or another in aerospace accepted and established qualification procedure) shall be used and documented according to the specified tests if not otherwise agreed between customer and supplier.
The manufacturer’s operations shall be an approved production organisation for aerospace products and shall demonstrate that it has implemented and is able to maintain a quality management system (e.g. according to EN 9100 or another in aerospace accepted and established quality management system).
Qualification obtained for tees also covers that of elbows and crosses.
6.2 Quality control records
The manufacturer shall maintain a record of inspection applied to each production batch for a minimum of 5 years. Records of chemical composition analysis, mechanical property tests showing conformance with the applicable material specification and metallurgical tests shall be made available to the purchaser (user) of each delivery batch of coupling parts upon request.
Each delivery batch shall be traceable to its production batch.
6.3 Acceptance conditions
The acceptance of a delivery batch shall be in accordance with 5.2 to 5.7.
Non-destructive tests for inspection of threads, finish, dimensions, marking, surface defects shall be conducted on a sampling basis in accordance with ISO 2859-1.
a) Classification of defects
Defects are classified in Table 5 according to the effect they have on safety and usability. Definition of classes shall be in accordance with ISO 2859-1.
b) Level of inspection
The following acceptable quality levels (AQL) shall apply to the defect classifications shown in Table 5.
Failure class Major: AQL 1,5
Failure class Minor: AQL 4.0
All defects not identified in Table 5 shall be inspected in accordance with the #minor defect classiflcation, AQL 4.0.
6.4 Rejection
Parts subjected to non-destructive tests and failing to conform to the requirements of these tests shall be rejected. Parts identified as having major defects during acceptance test require a rejection of all parts as above. Parts identified as having minor defects require the definition of a procedure by the quality assurance department of the purchaser (user).
6.5 Purchaser’s (user’s) quality control
The purchaser (user) may, on receiving of a delivery batch, proceed to inspect it by using the methods specified in 5.2 to 5.7, in full or in part, to ensure that the items conform to the required quality level, and to determine whether the delivery batch is acceptable.
This inspection may be carried out in the purchaser’s (user’s) factory, or by special agreement with the manufacturer, in the manufacturer’s factory.
7 Preparation for delivery
7.1 Cleaning
Before packaging, all parts shall be free from grease, oil, dirt or other foreign matter. No preservative compound shall be applied.
7.2 Preservation and packaging
Prior to packaging, couplings or their assembled components shall be protected by capping all threaded ends and pipe attachment ends with caps or plugs to avoid the introduction of foreign matter. Appropriate choice of plastic material, thread tolerances and design of caps/plugs shall prohibit contamination and damage to the dynamic beam seal during transportation or storage.
The parts shall be packed on cardboard flats tightly enclosed by a transparent bag (skin package) to ensure protection from damage. Each flat shall be pre-printed or a label affixed for identification. As an alternative, the parts may be packaged in polyethylene bags with enclosed identification labels or the bags may be pre-printed with the identification.
Unless otherwise agreed, nuts, ferrules and caps of one type and size shall be unit packaged in the quantity per unit as specified in Table 6.BS/EN 3275-2019 pdf download.
BS/EN 3275-2019 pdf download
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