What is a hammer drill?
Speaking of electric hammer drill bits, let’s first understand what is an electric hammer?
An electric hammer is based on an electric drill and adds a piston with a crankshaft connecting rod driven by an electric motor. It compresses air back and forth in the cylinder, causing periodic changes in the air pressure in the cylinder. As the air pressure changes, the electric hammer reciprocates in the cylinder, which is equivalent to using an electric hammer to continuously hit the rotating drill bit. Impact drill bits can be used on brittle parts because they produce rapid reciprocating motion (frequent impacts) along the drill pipe as they rotate. It does not require much physical labor and can drill holes in cement concrete and stone, but not metal, wood, plastic or other materials.
The disadvantage is that the vibration is large and will cause a certain degree of damage to the surrounding structures. For the steel bars in the concrete structure, ordinary drill bits cannot pass smoothly, and the vibration will also bring a lot of dust, and the vibration will also produce a lot of noise. Failure to carry adequate protective equipment may pose a health hazard.
What is an impact drill bit? They can be broadly distinguished by two handle types: SDS Plus and Sds Max.
SDS-Plus – Two pits and two grooves round handle
The SDS system developed by BOSCH in 1975 is the basis for many of today’s hammer drills. People no longer know what the original SDS drill bit looked like. The SDS-Plus system as it is now known was jointly developed by Bosch and Hilti. Usually translated as "Spannen durch System" (quick-change clamping system), its name is taken from the German phrase "S tecken – D rehen – Safety".
The great thing about the SDS Plus is that you just push the drill bit into the spring drill chuck. No need to tighten. The drill bit is not firmly attached to the chuck, but slides back and forth like a piston. When rotating, the drill bit will not slip out of the chuck due to the two dimples on the round tool shank. SDS Shank Drill Bits for Hammer Drilling are more efficient than other types of shank drill bits due to their two flutes, allowing for faster high-speed hammering and increased hammering efficiency. In particular, hammer drill bits for hammer drilling in stone and concrete can be attached to a complete shank and chuck system made specifically for this purpose. The SDS quick release system is the standard attachment method for impact drill bits today. Not only does it provide a quick, easy and safe way to clamp a drill bit, it also ensures optimal power transfer to the drill bit itself.
SDS-Max – five pit round handle
SDS-Plus also has limitations. Generally, the handle diameter of SDS Plus is 10mm, so drilling small and medium holes is not a problem. When drilling large or deep holes, insufficient torque can cause the drill bit to get stuck and the handle to break during operation. BOSCH developed SDS-MAX based on SDS-Plus, with three grooves and two pits. The handle of the SDS Max has five grooves. There are three open slots and two closed slots (to prevent the drill bit from flying out). Commonly known as three grooves and two pits round handle, also known as five pits round handle. The SDS Max handle is 18mm in diameter and is better suited for heavy-duty work than the SDS-Plus handle. Therefore, the SDS Max handle has stronger torque than SDS-Plus and is suitable for using larger diameter impact drill bits for large and deep hole operations. Many people once thought that the SDS Max system would replace the old SDS system. In fact, the main improvement to this system is that the piston has a longer stroke, so when it hits the drill bit, the impact is stronger and the drill bit cuts more efficiently. Despite the upgrade to the SDS system, the SDS-Plus system will continue to be used. The SDS-MAX’s 18 mm shank diameter results in higher costs when machining smaller drill sizes. It cannot be said to be a replacement for SDS-Plus, but rather a complement. Electric hammers and electric drills are used differently abroad. There are different handle types and power tools for different hammer weights and drill bit sizes.
Depending on the market, SDS-plus is the most common and typically accommodates drill bits from 4 mm to 30 mm (5/32 in. to 1-1/4 in.). Total length 110mm, maximum length 1500mm. SDS-MAX is typically used for larger holes and picks. Impact drill bits are typically between 1/2 inch (13 mm) and 1-3/4 inch (44 mm). Overall length is typically 12 to 21 inches (300 to 530 mm).
Post time: Nov-10-2023
