What is ISO 28927-1 - Angle and vertical grinders test methods about?
ISO 28927-1 specifies a laboratory method for measuring hand-transmitted vibration emission at the handles of hand-held power-driven angle and vertical grinders. ISO 28927-1 is a type-test procedure for establishing the magnitude of vibration in the gripping areas of a machine fitted with a specified test wheel and run under no‑load conditions. The method has been established for surface grinding tasks only. Cutting and sanding generally create lower vibrations. ISO 28927-1 intended that the results be used to compare different models of the same type of machine.
ISO 28927-1 is applicable to hand-held machines, driven pneumatically or by other means, intended for grinding, cutting-off, and rough sanding, with bonded, coated, and super-abrasive products and with wire brushes for use on all kinds of materials.
Note: It is not applicable to die grinders or straight grinders.
Who is ISO 28927-1 - Angle and vertical grinders test methods for?
ISO 28927-1 on angle and vertical grinders test methods is useful for:
- Manufacturers of handheld portable power tools, angle and vertical grinders
- Product designers/design engineers 
- Quality control personnel 
Why should you use ISO 28927-1 - Angle and vertical grinders test methods?
ISO 28927-1 is a type-C standard as stated in ISO 12100. When requirements of this type-C standard are different from those which are stated in type-A or -B standards, the requirements of this type-C standard take precedence over the requirements of the other standards for machines that have been designed and built according to the requirements of this type-C standard. The vibration test codes for portable hand-held machines given in ISO 28927-1 are based on ISO 20643, which gives general specifications for the measurement of the vibration emission of hand-held and hand-guided machinery. ISO 28927-1 specifies the operation of the machines under type-test conditions and other requirements for the performance of type tests. The structure/numbering of its clauses follows that of ISO 20643. The basic principle for transducer positioning first introduced in the EN 60745 series of European standards is followed, representing a deviation from ISO 20643 for reasons of consistency. The transducers are primarily positioned next to the hand in the area between the thumb and the index finger, where they give the least disturbance to the operator gripping the machine. It has been found that vibrations generated by grinders vary considerably in typical use. This is largely due to the variances in the unbalance of the machine with the grinding wheel mounted. The unbalance also changes when the wheel is worn through operation.
In order to provide a method that gives good measurement reproducibility, the procedure adopted in ISO 28927-1 uses a test wheel of known unbalance mounted on a machine and run under no-load conditions. The unbalance for the different types of test wheel is chosen to give vibration values that are as far as possible according to ISO 20643. The procedures of ISO 5349 are required whenever exposure at the workplace is to be assessed. Underestimation of the vibration for machines equipped with technical means to automatically reduce unbalances is taken into account by multiplying the vibration values of such machines with a correction factor of 1,3.
What’s changed since the last update?
BS EN ISO 28927-1:2019 is the UK implementation of EN ISO 28927‑1:2019 and supersedes BS EN ISO 28927‑1:2009+A1:2017, which is withdrawn. The editorial changes as compared to the first edition published in 2017 are:
- Table C.4, in "Radius to centre of hole", change rh to rh
- Table C.4, in "Radius to centre of threaded hole", change rt to rt
- Figure C.4, change rs to rt
- Figure C.4, change rt to rh
- Figure C.4, in the key, change rs to rh
