ISO 8168:2016 pdf free download.Aerospace — Bolts, with MJ threads, made of heat and corrosâon resisting steel, strength class 1 100 MPa — Procurement specification.
1 Scope
ISO 8168 specifies the characteristics and quality assurance requirements far Mj thread bolts made of heat and corrosion resisting steel, at strength class 1 100 MPa. for aerospace construction.
It Is applicable whenever It Is referenced In a definition document,
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of ISO 8168. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2859.1:1999, SamplIng procedures for Inspection by atiribuces — Part 1: Sampling schemes indexed by acceptance quality limit jAQL.) fur lot.by-Iot Inspection
ISO 3452-1, Nan-destructive testing — Per,et rant testing — Part I: General principles
ISO 4288, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and procedures for the assessment of surface texture
ISO 5855-2. Aerospace — Mi threads — Part 2: Limit dimensions for bolts and nuts
ISO 6892-1. Metallic materials — Tensile resting — Part 1: Method of test at room temperature
ISO 7870.1. Cant tel charts — PUrl 1; General guidelines
Iso 7870-2. Control charts — Part 2: Shewhart control charts
ISO 7870-3. Control charts — Part 3: Acceptance control charts
ISO 7961, Aerospace — Bolts — Test methods
ASTM El 12:2004, Standard Test Methods for Determining Average Grain Size
3 Terms and definitions
For the purposes of ISO 8168, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
The inspections shall be repeated on any bolt if the manufacturing conditions have been modified. TabIe2 indicates the allocation of bolt samples for the inspections.
4.3 Acceptance Inspection conditions
Inspections shall be carried out on each production batch or Inspection lot. Bolts from the batch or lot to be Inspected shall be selected by simple random sampling.
Each bolt may be submitted to several Inspections, provided that none of the characteristics to be verified has been previously altered during any of these inspections.
The bolts to be subjected to destructive inspections may be those on which non-destructive inspections have been carried out.
If a more stringent inspection Is deemed necessary all or part of the qualification inspections may be performed during the acceptance inspections. In this case, the number of bolts submitted is the same as that submitted for the qualification inspection.
Production batches or Inspection lots declared unacceptable after the production acceptance inspections shall be submitted for re.inspection only after all the defective units have been removed and/or defects have been corrected. In this case, the attribute(s) that caused the rejection shall be verified using a sample of twice the normal size with the same number of defective items acceptable.
4.4 Use ofstatistlcal process control (SPC)
When a characteristic is obtained by a controlled statistical process, the manufacturer has the option. in order to declare conformity of the characteristic, to forgo the final systematic sampling provided In this document, if he Is capable of formally justifying this choice by using lSO/TR 13425 and the standards quoted in it as a basis,
This justification will Include the following phases:
— analysis of the key characteristics of the product;
— analysis of the risks for each implemented process:
— determination o’ the parameters and/or characteristics to be respected under SPC
— determination of the capabilities of each process:
— drawing up olan inspection plan and Integration in the manufacturing Process;
— drawing up of routes and control charts (ISO 7870-3, ISO 7870-1. ISO 7870-2);
— use of control charts for data consolidation:
— determination of the audits to be run and the control to be carried out to ensure reliability of the device.
To be usable in production, this process shall be validated beforehand by the qualifying body, either during the qualification phase, or a posteriori according to the case, by analysing the Justificatory file and the results of the qualification Inspections such as provided for in ClauseS. Such an SPC process is not applicable to destructive tests apart from the stress durability test.
S Requirements
The requirements of ISO 8168 are given in Table .1 and, unless otherwise specified, they apply to bolts that are ready for use. The test temperature, unless otherwise specified, shall be the ambient temperature. These requirements complement the requirements of all other standards or specifications referenced in the definition document.