Elaboration of a standard procedure for the measurement of vibration emitted by percussive tools--application to breakers.

An Evaluation of the Standardized Chipping Hammer Test Specified in ISO 8662-2

“…Several different methods have been proposed for these tool assessments. One method requires the chipping of a uniform layer of mild steel, 2 mm thick, with a representative chipping hammer (Bitsch et al, 1986). Because measuring vibration on a chisel is extremely difficult (Clarke et al, 1986), Reynolds and Markle (2001) developed an indirect method to measure these impact vibrations.…”

Health hazard evaluation report: HETA #2001-0073-2869, City of Cincinnati Sewers, Water Works & Public Services, Cincinnati, Ohio.

“…14 The weighted rms values of the Sullair paving breakers are also in the range of those measured on similar tools. 15,16 However, the values measured on the old jackhammers are generally higher than those reported in the scientific literature. One of the possible reasons is that the test working material (steel + good concrete) was very hard, resulting in a high level of vibration.…”

Parameters Optimization and Energy Absorption Evaluation of the Steel Ball Friction Energy Absorber

“…Clarke et al fixed an accelerometer into the mounting block welded on the chisel to measure the vibration emitted by percussive tools, but problems such as the fracturing of the weld holding the block to the chisel, and the unscrewing of the stud holding the accelerometer to the block were encountered during the test [14]. Because measuring vibration on a chisel is extremely difficult, Bitsch et al fixed the accelerometers on the handle instead of the chisel and developed a test code for the measurement of vibration from percussive tools under laboratory conditions [15].…”

“…Bitsch et al used six different energy absorption methods, which are the hydraulic base, the steel shot, the actual breaking of concrete, the AFNOR concrete block, and the pointed chisel embedded in concrete, to simulate the actual working condition in the handle vibration measurement of percussive tools, the results showed that the different methods tested were all valid and comparable to those obtained when real concrete was broken. Moreover, they proposed that, for the steel shot energy absorption method, the box diameter should be at least 500 mm, and the depth of the shot should be 300 mm [15]. According to international standard ISO 8662-2, the energy absorber device should avoid energy reflection, and the reflected energy should not exceed 20% of the incident energy [17], but it is not mentioned in the comments of Bitsch et al [15].…”

“…Moreover, they proposed that, for the steel shot energy absorption method, the box diameter should be at least 500 mm, and the depth of the shot should be 300 mm [15]. According to international standard ISO 8662-2, the energy absorber device should avoid energy reflection, and the reflected energy should not exceed 20% of the incident energy [17], but it is not mentioned in the comments of Bitsch et al [15]. Zheng et al presented the working mechanism of an energy absorber by the friction of steel balls and obtained the reflective properties of the steel balls, the optimum cross-section ratio of the absorber to the drill rod, the energy absorption coefficient, and the reasonable ball column length by using the wave principle [21].…”