What is BS 89250 – Thermoplastic moulded components about?
BS 89250 specifies quality levels for imperfections in joints in thermoplastic moulded components due to the joining process. BS 89250 defines dimensions of typical imperfections which might be expected in normal fabrication. BS 89250 may be used within a quality system for the production of joints.
BS 89250 has been developed to help organizations better understand quality levels for imperfections in the following thermal joining processes:
- Ultrasonic welding
- Ultrasonic spot welding
- Infrared welding
- Hot gas convection welding
- Linear vibration welding
- Orbital vibration welding
- Spin welding
- Laser welding
- Hot plate welding
- Heat staking: hot air; electrical, infrared and ultrasonic
The quality level necessary in each case is defined by the application specification, or the responsible designer, in conjunction with the manufacturer, user, and others involved in the design process. The quality levels refer to production quality and not to the fitness for purpose of the manufactured product.
Note: BS 89250 is not applicable to onsite joining processes.
Who is BS 89250 – Thermoplastic moulded components for?
BS 89250 on thermoplastic moulded components is useful for:
- Manufacturers and designers of thermoplastic components for industries such as:
- Electrical
- Computer
- Automotive and aerospace
- Medical and packaging
Why should you use BS 89250 – Thermoplastic moulded components?
BS 89250 can be used as a reference in the drafting of application specifications. BS 89250 contains a simplified selection of thermal joining process imperfections in thermoplastics based on the designations given in BS EN 14728.
The quality levels need to be prescribed before the start of production, preferably at the enquiry or order stage. They provide basic reference data and are not specifically related to any particular application. In some cases, it might be necessary to specify different quality levels for different imperfections in the same joint. BS 89250 specifies three quality levels to permit application for the range of joining processes listed above.
Imperfections are quoted in terms of their actual dimensions, and their detection and evaluation might require the use of destructive and / or non-destructive testing. The detection and sizing of imperfections are dependent on the inspection methods and the extent of testing specified. BS 89250 walks you through the process of tailoring your quality levels and tests at the enquiry / order / design stage while involving stakeholders. This facilitates clear communication in terms of client expectations.
