China Drill Bits Material Manufacturers & Factory

At Jiangxi Zhongfu Cemented Carbide Co., Ltd., our 24-year reputation rests on our strict raw material policy: we formulate 100% of our production utilizing virgin Ammonium Paratungstate (APT) refined tungsten powders. We do not blend secondary recycled scrap or zinc-reclaimed WC into our drill bit grades. Recycled powders introduce uncontrollable trace impurities (such as iron, calcium, and titanium contamination) that act as stress concentration notches, leading to premature fracture during downhole percussive stress. Every incoming powder batch undergoes strict inductive coupled plasma (ICP) mass spectrometry analysis before automated wet milling and spray drying.

Conventional vacuum sintering relies strictly on capillary action to consolidate the carbide powder, which frequently leaves submicron residual pores (Type A and B porosity) within the cobalt binder channels. Sinter-HIP applies up to 100 bar of ultra-pure inert Argon gas during the final liquid-phase sintering stage (1400°C–1450°C). This extreme hydrostatic pressure collapses microscopic micropores, elevating density to near 100% theoretical limits. For high-impact geotechnical drill bits and PDC backing substrates, Sinter-HIP elevates transverse rupture strength (TRS) by 15% to 30%, virtually eliminating catastrophic downhole head shear.

Cobalt remains the superior binder for extreme mechanical wear, heavy impact, and dynamic percussive loading due to its unique allotropic phase transformation under strain, which absorbs fracture energy. However, Cobalt is ferromagnetic and susceptible to rapid electrochemical leaching in acidic slurries ($pH < 6$). We recommend Nickel-bonded grades (such as our Ni-binder round rods and plates) for non-magnetic downhole Measurement While Drilling (MWD) housings, Directional Drilling guidance subs, and marine subsea valves where severe galvanic corrosion or magnetic sensor interference would compromise operation.

Yes. Custom component manufacturing according to buyer drawings (STEP, DWG, DXF, or PDF format) represents over 60% of our daily foundry operations. Our manufacturing equipment covers CNC automated powder compaction presses, cold isostatic pressing (CIP) for large blocks up to 500mm, CNC green-state machining, and finish grinding including centerless grinding (down to h6 tolerance on cylindrical rods) and optical profile surface grinding with surface finishes down to $Ra\, 0.1\,\mu\text{m}$.

Standard inventory items (such as h6 ground rods, common SPUB/SNMX inserts, and standard plate stock) dispatch within 3 to 5 business days. Custom tool blank tooling development, pressing, Sinter-HIP firing, and precision grinding typically require 18 to 25 calendar days depending on geometric complexity. For urgent prototypes, our rapid-response prototyping cell can complete sample runs within 10 days. We export directly to over 20 countries via air courier (DHL/FedEx/UPS), air freight, and full container marine shipping originating through Shanghai, Ningbo, or Shenzhen ports.

Due to the mismatch in thermal expansion coefficient between tungsten carbide ($\approx 4.5 \times 10^{-6}/\text{K}$) and structural alloy steel bit bodies ($\approx 12 \times 10^{-6}/\text{K}$), residual thermal stresses can trigger brazing cracks if handled incorrectly. We advise using silver-copper sandwich tri-foil brazing shims (such as BAg-22 or BAg-24) or copper-zinc brazing alloys with active flux. Induction heating should be applied evenly to the steel socket rather than directly onto the carbide tip, ensuring operating temperatures do not exceed 750°C. Controlled slow cooling in dry vermiculite or insulating powder is essential to allow ductile stress relief in the copper core of the shim.