ASTM A519 4140 Tempering Seamless Steel Pipe

Specifications

1. 1.       Steel grade and chemical composition

         Grade: ASTM A519 4140

        Chemical composition (wt%)

Cev=C+Mn/6+(Si + Cu+ Ni)/15 + (Cr+Mo+V)/5

   2.The offset of product analysis according to meet Tables 2.

 Metallurgy methods: Electric Arc Furnace (EAF) ——→ Refine——→ Vacuum Degassed(VD)/RH

3.  Delivery condition:QUENCH AND TEMPER

Stress free with minimum tempering temperature of 620°C(1150°F).Report Heat Treatment Cycle including Times, Temperatures, and Quench Media

4. The sizes and the tolerance

O.D. Tolerance±0.85%, aiming 0.75%, W.T. Tolerance±10%, aiming 7.5%,with a maximum difference between max. and min. W.T. in the same section  of 14%. Straightness: 1.5 mm maximum in any 1 meter section, according with ASTM A519. Sizes are to be indicated with the contracts.

5. /Mechanical properties

5.1Mechanical properties:The mechanical properties on quench and temper should according to the table 3

5.2 Tensile specimens shall be oriented in the longitudinal direction and tested in accordance with ASTM A370. All straightening, stress-relieving, heat treating and processing shall be completed before test specimens are cut from the material. All tensile testing is to be performed at the mid-wall location.

Perform Charpy Impacts at  14°F (-10°C). Full size specimens shall be used whenever possible, and tested in a transverse direction whenever possible. A test shall consist of a set of three specimens taken from one location from a single tube.  Report absorbed energy, lateral expansion. The min. energy for full size specimen (average of the results on 3 specimen sets), will be 20ft/lbs (27J). 15ft/lbs (27J) min. single value  When the pipe size will not permit to obtain full size specimens, reduced size specimens, according to the hierarchy established by API 5CT table E10 shall be used and table E9 absorbed energy reduction factor shall apply.

6.  Austenitic grain size 5 and finer ; Reduction Ratio≥4:1

7. Surface of the material

Surface of the material must be free of visual harmful defects that could affect the use of final products. The surface must free from cracks, lap, and other detrimental, injurious, defects. Other non-injurious defects such as corrosion, incrusted scale scabs, etc. must be avoided. UT is okay.

8. Identification and Packing

Standard export packing.   Bare in bundles with min. 4 strips and 2 wires.Each bundle should be about 2.5 metric ton.

       Heat number to be stenciled on the surface of each tube

9. Quality Certificate

The mill certificate shall meet the exporting specs by XINYEGANG and must contain:

---ASTM A519

---Condition of Delivery

---Electric Furnace

---Grade

---Chemistry

---Mechanical Properties

---Ce

---Grain size

---Reduction ratio

---“Mercury Free”

---“Free from Harmful Radioactivity”

---“No Weld Repairs”

10. Any issues occurred during production and transaction will be friendly settled down by both parties.