• Alloy steel pipe
  • Ductile Iron Pipe
  • Carbon Steel Pipe
  • OCTG Steel Pipe
  • Stainless Steel Pipe
Product
contact us

Address:Beijing Road, Yunhe District, Shengji Building #1802 ,Cangzhou City, Hebei

Contact:Lucky

Phone:86-15003171886

E-mail:jinxiaolong0221@gmail.com
         beitesteelpipe@gmail.com


  • GB/T 3639 Precision Seamless Tubes
Title:
Tel:
E-mail: *
Content: *
Verification Code:
 
  •  
    GB/T 3639 Grade 10、20、35、45、Cold-drawn or cold-rolled precision seamless tubes
     
    Standard: GB/T 3639
     
    This standard is applicable to the manufacture of mechanical structures, hydraulic equipment, automotive cold-drawn or cold-rolled precision seamless steel tubes with special dimensional accuracy and high surface quality requirements.
     
     
    Main grades:
    Grade 10, Grade 20, Grade 35, Grade 45
     
     
    GB/T 3639 Cold-drawn or cold-rolled precision seamless tubes Quick Details
    Company Name: Beite steel pipe
    Country/Region: China
    Main grades: Grade 10, Grade 20, Grade 35, Grade 45
    FOB Price: US $900-1500 / Ton | 1 Ton/Tons (Min. Order)
    Delivery Status: +BK, +BK W, +BK S, +GBK, +NBK
    Port of Shipment: Tianjin, China
    Payment: L/C or T/T
    Delivery: 7-15 days after payment
    Package:Standard export package,suit for all kinds of transport, or as required
    Certificate: ISO 9001-2000, PED 97/23/EC, ASME, DNV
     
     
    GB/T 3639 Cold-drawn or cold-rolled precision seamless tubes Dimensional Range & Specification
    Outside Diameter: 4.0mm - 200.0mm
    Wall thickness: 3.0mm - 12.5mm
    Length: 6000mm, 12000m or specified length as required.
     

     
    Manufacturing
    The steel pipe is manufactured by cold drawn or cold rolled.
     
     
    Steel pipe according to delivery status:
    Cold working / hard (BK), cold working / soft (BK W), stress relief annealing after cold working (BK S), annealing (GBK), normalizing (NBK).
     

    Delivery status Code Description
    Cold working / hard B K After the final cold working, no heat treatment is performed, so that the tube can only be deformed very little.
    Cold working / soft B K W After the final heat treatment, a small amount of cold working is performed to allow limited cold deformation (for example, bending and flaring) when the steel pipe is reworked.
    Stress relief annealing after cold working B K S After cold working, it is annealed below the Acl point to eliminate cold working stress.
    Annealing G B K After the final cold working, the steel tube is completely annealed under a protective gas
    Normalizing N B K After the final cold working, the normalizing of the steel pipe under protective gas
     
     

     
    Chemical composition of GB/T 3639


    No. Uniform
    numeric
    code
    Designation Chemical composition (mass fraction)/%
    C
     
    Si
     
    Mn
     
    P S Cr Ni Cu a
        
    2 U20102 10 0.07~0.1 3 0.17~0.37 0.35~0.65 0.035 0.035 0.15 0.30 0.25
    4 U20202 20 0.17~0.23 0.17~0.37 0.35~0.65 0.035 0.035 0.25 0.30 0.25
    7 U20352 35 0.32~0.39 0.17~0.37 0.50~0.80 0.035 0.035 0.25 0.30 0.25
    9 U20452 45 0.42~0.50 0.17~0.37 0.50~0.80 0.035 0.035 0.25 0.30 0.25
    Any element not specified in this table shall not be added without agreement of the users. Measures shall be taken to prevent steel scrap or other materials from bringing in element which influences performance of steels.
    a  Copper content for steel used for hot press working shall not be greater than 0.20%;
     
     

    Physical properties 
    of GB/T 3639
     
    Grade Delivery status
    B K B K W B K S G BK N B K
    Tensile strength,
    Mpa
    Elongation,
    %
    Tensile strength,
    Mpa
    Elongation,
    %
    Tensile strength,
    Mpa
    Elongation,
    %
    Tensile strength,
    Mpa
    Elongation,
    %
    Tensile strength,
    Mpa
    Yield Strength Elongation,
    %
    10 410 6 375 10 335 12 335 24 335 205 24
    20 510 5 450 8 430 10 390 20 410 245 20
    35 590 4 550 6 520 8 510 17 530 315 17
    45 645 4 630 5 610 7 590 14 600 355 14
    Note: For steel pipes with an outer diameter of not more than 30 mm and a wall thickness of more than 3 mm, the minimum yield point can be reduced by 10 MPa.
     
     

    The end of 
    Precision seamless steel pipe
    The end faces of the steel pipe should be perpendicular to the axis of the steel pipe, and the burrs of the cut should be removed.
     
     
    Testings:
    Dimensional inspection: The size and shape of the steel pipe are measured and inspected one by one using a measuring tool that meets the accuracy.
    Surface quality: The inner and outer surfaces of the steel pipe shall be visually inspected one by one under conditions of sufficient illumination.
    Chemical composition: Take 1 sample per furnace number for chemical composition testing.
    Tensile test: Take 1 sample per batch for tensile test.
    Compactness test: The GB/T 3639 steel pipe is tested one by one
    Surface roughness inspection: Each sample is taken on each of 2 steel pipes for inspection.
     
     



     
    Tag example
    Cold-rolled precision seamless steel pipe made of 20 steel with an outer diameter of 50 mm and an inner diameter of 30 mm, cold worked/hard state, marked as:
    Finishing 20-∅50X ∅ 30BK-GB/T 3639- 2017
     
    Cold-rolled precision seamless steel pipe made of 10 steel with an outer diameter of 38 mm, a wall thickness of 3 mm and a length of 5 000 mm, cold worked/soft state, marked as:
    Finishing 10-∅38 X 3 X 5000BKW-GB/T 3639- 2017
     
    Cold drawn precision seamless steel pipe made of 35 steel with an inner diameter of 30 mm, a wall thickness of 2 mm and a length of 1 800 mm, and a stress-relieving annealing state, marked as:
    Fine extraction 35- inner ∅30 X 2 X 1 800  BKS-GB/T 3639- 2017
     





    HOME |  Company |  Product |  News |  KnowLedge |  Equipment |  Contact | 

    Technical Support:CZWLWL.COM  Address:Beijing Road, Yunhe District, Shengji Building #1802 ,Cangzhou City, Hebei

    Phone:86-15003171886   站长流量统计