For diamond core drill bit, welding is the most used method of attaching diamond segment on the core barrel. Diamond core drill bits are ideal for drilling holes in hard materials like these:
- Glass, beach glass, fused glass, and sheet glass
- Stones, jewels, rocks, pebbles, and minerals
- Ceramics, porcelain, tiles, glazed pottery, dinnerware, and china
- Antler, shell, bone, and fossil
- Extremely hard woods
This article is mainly about the production process and features of welded diamond core drill bit.
Manufacturing process of diamond core drill bit can be divided into the following six parts.
Diamond, iron, nickel, cobalt and other metal powder are selected according to the production requirements*. Then binding agents are mixed with selected powders, which is often carried out using pendulum motion mixers. (* Diamond-related parameters are taken into consideration to meet the individual requirements of a given application, including diamond type, grit size and concentration.
Diamond-matrix* mixture then will be injected into a mold under heat and pressure to form a segment. Once formed, the segments are cooled and deburred. The backer side is machined for a precise fit with the steel core. The segments are inspected for material integrity, shape and balance. (*One of the important requirements for matrix is to firmly hold the diamond particles and the pressing will help to reach this gold. Under the application conditions the diamond-matrix interactions occur in a variety of forms depending on the size and shape of each individual diamond particle.)
To attach segments to the steel core, BSP uses brazing machines fitted with high-frequency induction heater and machines for laser-welding. High frequency welding involves a length of solder placed on the segment, which fuses the segment to the landings that protrude from the steel core when heated. While laser welding doesn’t involve the solder.
After segments are attached the core barrel, we remove burrs and oxides from the diamond core drill bit surface. Anticorrosive paint on the steel core after polishing.
Performance and safety tests are implemented based on EN 1323.
Qualified products will be printed, laser marked and packed according to customers’ requirements.
The bending strength of a laser-welded diamond core drill bit may achieve 1800 MPa, compared with 350-600 MPa for the high frequency welded diamond core drill bit, laser welding practically eliminates the possibility of segment detachment. Both methods, applicable to different applications, can offer strong welding adhesion between the segment and the core barrel and greater stability under high temperature. With 20-year experience of diamond tools manufacture, BSP TOOLS has strict requirements on metal matrix and diamond particles selection. Our various formulas for different application are well received, which have been keeping upgrading.) If you want to know more, feel free to contact BSP – core bit and diamond saw blades factory.