ISO 9518 pdf download.Forestry machinery — Portable chain-saws — Kickback test
1 Scope
This International Standard specifies the methodology for determining the kickback potential of a gasoline-powered chain-saw, complete with guide bar and saw chain. This International Standard has been demonstrated to be an accurate method of measurement for evaluating computed kickback angles and energy associated with chain-saw kickback for chain-saws with engine capacity up to 80 cm 3 . It is not intended to evaluate chain-saws with an engine capacity of above 80 cm 3 . Furthermore, because of physical size limitations of the kickback machine, testing of units with guide bar cutting length in excess of 63 cm is not recommended. NOTE — Although this International Standard is applicable to gasoline-powered chain-saws, the kickback machine and test procedure ought to be also suitable for testing of electric powered chain-saws. To aid in application of this test method to electric powered units, some instructions are included in this document that relate specifically to electric chain-saws.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 6535:1 991 , Portable chain-saws — Chain brake performance . BOM-01 00, Kickback machine — Bill of materials. 2)
3 Definitions
For the purposes of this International Standard, the following definitions apply. 3.1 bar tip guard shield that prevents contact with the chain at the tip of the guide bar and which may be removable and replaceable 3.2 chain brake lever device, usually the front hand guard, used to activate the chain brake 3.3 computed kickback angle angle used as a measure of the reaction of a hand-held chain-saw, backward and upward toward the user, when subjected to a rotational kickback under simulated conditions See figure 1 . 3.4 contact angle angle between the surface of the test specimen and a perpendicular to the guide bar centreline 3.5 data set group of data points, all taken at the same test conditions 3.6 horizontal system portion of the kickback machine used to measure the horizontal energy of the kickback reaction 3.7 impact test sequence involving releasing the specimen into contact with the moving saw chain at the guide bar tip to create a simulated kickback reaction 3.8 kickback rotational kickback rapid upward and backward motion of the saw which can occur when the moving saw chain near the upper portion of the tip of the guide bar contacts an object such as a log or branch 3.9 kickback machine apparatus used to measure the energy generated by a chain-saw kickback under controlled conditions 3.10 power head chain-saw without the guide bar and chain 3.11 rotary system portion of the kickback machine used to measure the rotary energy of the kickback reaction 3.12 specimen test specimen block of medium density fibreboard used as an object for the saw chain to engage in a simulate kickback
4 Test method
4.1 Principle The flat surface of a wood-like specimen is thrust into contact with the moving saw chain at the tip of a chain-saw guide bar, in order to produce a simulated kickback reaction. This takes place under controlled conditions in apparatus designed to measure the magnitude of rotary and horizontal energies generated during the resulting kickback reaction. A step-by-step search, covering a range of critical test conditions, determines the peak energy values to be used in computing kickback angle. This peak value is intended to simulate the most severe conditions reasonably expected to be encountered by typical users. Since there may be some variability, several impacts are made under each set of conditions and the results averaged.