Large diameter seamless steel quality distinction approach:
1. The ingredients are uniformly large diameter seamless steel tonnage cold shear is also high, so smooth and neat end face of the cutting head, when you see the end face of the cutting head off the meat often have the appearance of, or rugged look dull large-diameter seamless steel pipe division, do not pick up these are defective in.
2. Under no circumstances vernier caliper, you need to be weighed checked shoddy large diameter seamless steel pipe due to impurities content and the density of steel is small, but the scale of tolerance is grim, so lightweight large-diameter seamless steel, do not pick and choose.
3. Look inside diameter of scale: large-diameter seamless steel pipe defective inner diameter larger scale will be shaken.
4. seen factory trademark: Excellent large diameter seamless steel pipe trademarks and printing are very standardized.
5. Look longitudinal reinforcement: large-diameter seamless steel pipe defective longitudinal reinforcement is often called wavy.
6. Look steel shape: some small manufacturers to produce large diameter seamless steel pipe because there is no traffic, packing will be very lax, so the sides will be oval.
7. Have look at the outer surface of Ma: Ma face rugged appearance occurs due to wear groove grim, steel table and Mina irregularities emerged.