Cordless rotary hammers are preferably used for outdoor applications and in situations where mains power is not available or a hindrance (e.g. construction of scaffolding). Due to their performance capabilities and easy manageability they are also increasingly used for occasional fastening operations.
Cordless rotary hammers are single-purpose tools equipped with a hammer impact system. They are recommended for hammer drilling in hard building materials such as concrete and natural stone. The typical drilling range corresponds to fastening technology with drilling diameters of 30 mm. The drilling performance in the most frequent application area of 20 mm corresponds to mains-powered tools in comparison to which they are superior in handling due to the lack of a power supply cable.
The function of the impact system requires a certain minimum input power and therefore the efficiency of hammer impact systems in cordless rotary hammers must be particularly high. Purely mechanical impact systems have very little friction loss. Especially in case of low outdoor temperatures as they are common during the cold season they do not require a ?warm-up period?This saves valuable battery power. Although the friction losses of pneumatic impact systems are slightly higher, their running smoothness is slightly better. Due to the required power input of their impact systems, high-performance cordless rotary hammers are mainly available in the upper voltage segment (20V).