Gpc

When evaluating Graphitized Petroleum Coke (GPC), the most critical parameters are Fixed Carbon content (typically >98.5% or >99%), Sulfur content (ideally <0.05%), and Nitrogen content (usually <300ppm). High-quality GPC is produced through graphitization at temperatures between 2,500°C and 3,000°C, which ensures a high degree of carbon atom alignment. You should also verify the Ash content (<0.5%) and Volatile matter (<0.5%) to ensure minimal impurities during the steelmaking or casting process.

GPC acts as a superior recarburizer (carbon raiser). Its high absorption rate (often exceeding 90-95%) and fast dissolution speed significantly reduce smelting time. Because of its low sulfur and low nitrogen characteristics, it prevents the formation of nitrogen-related defects in steel and ensures the stability of the graphite nodules in ductile iron casting, leading to better mechanical properties and reduced scrap rates.

Particle size selection depends on the furnace type and application. Common sizes include 0.2-1mm, 1-5mm, and 5-10mm. For induction furnaces, 1-5mm is often preferred for optimal absorption. It is vital to ensure low moisture content (<0.5%) to prevent hydrogen pickup in the molten metal and to avoid safety risks like splashing during charging.

Reliable suppliers should provide an ISO 9001 certification for quality management. More importantly, every batch should be accompanied by a COA (Certificate of Analysis). For international trade, third-party inspections by agencies like SGS or Intertek are highly recommended to verify that the chemical composition (Carbon, Sulfur, Nitrogen) matches the technical data sheet provided by the manufacturer.

The most common risk in GPC procurement is the substitution of GPC with Semi-Graphitized Petroleum Coke or Calcined Petroleum Coke. To mitigate this, request a pre-shipment inspection (PSI) and specifically test for Nitrogen levels and Sulfur levels, as these are the hardest to fake. Use Made-in-China.com's secured payment and inspection services to ensure funds are only released upon verification of quality.

GPC prices are sensitive to raw material (petroleum coke) costs and electricity rates in the manufacturing region. Negotiate based on Fixed Carbon tiers and ask for volume-based discounts (e.g., 50+ tons). For shipping, GPC is usually packed in 1mt jumbo bags or 25kg bags inside jumbo bags. Ensure the contract specifies waterproof packaging and UV-resistant bags to prevent contamination and bag breakage during sea transit.

Buyers must stay informed about export tax rebates or environmental protection-related production halts in China, which can cause sudden price fluctuations or supply shortages. Ensure your supplier provides a Certificate of Origin to benefit from any applicable Free Trade Agreements (FTAs) and check for any anti-dumping duties specific to carbon products in your destination country.

For new suppliers, utilize Letter of Credit (L/C) or Escrow services provided by reputable platforms like Made-in-China.com. Regarding shipping, FOB (Free On Board) is generally recommended for experienced buyers to maintain control over freight costs, while CIF (Cost, Insurance, and Freight) may be more convenient for first-time buyers. Always ensure the cargo is insured against moisture damage and contamination.