Needle scaler
Needle scaler ( needle hammer, needle gun, needle knocker, pneumatic needle, English Needlegun-Scaler) are hand-held, mostly pneumatically operated devices for removing rust or scale . Devices with an electric drive are also used less frequently. The process is limited to the machining of solid metal parts, as the high energy with which the needles hit the surface would penetrate thinner sheets (<3–5 mm). Needle scaler are especially suitable for removing thick layers of rust or scale that cannot be efficiently processed by sandblasting alone.
function
A shaft encases the internal mechanical parts of the nail assembly and nail plate. The nail plate has holes in which the needles are guided. A pneumatic (or electric) drive lets the needles shoot forward one at a time. When the needles hit the surface to be processed, rust or scale flakes off. The most effective way to work is at a 90 ° angle to the surface to be processed.
Areas of application
Needle scaler is used to remove loose paint, rust, or scale and to clean the surface before applying a coating . In most cases, several machining passes are required to produce sufficient surface cleanliness . Otherwise, especially in the case of thick layers of rust and scale, the process can serve as a preparation for subsequent processing by sandblasting or bristle blasting etc.
Health effects
Prolonged work on the needle scaler can cause a so-called vibration-induced vasospastic syndrome (hand-arm vibration syndrome) due to the vibrations introduced into the body , which is why the use of needle scaler is only permitted to a limited extent in industrial areas. An exception are needle guns that remain below the exposure limit value of 5 m / s² or, better still, below the trigger value of 2.5 m / s².