Common size on stock, Special sizes needs new production.Can cut to Size, cut to Shape.
EMERSONMETAL
| Quantity: | |
|---|---|
The production process of precision tube is more complicated, mainly including the following steps:
Raw material preparation: Take round tube billet as raw material and cut it into billet of certain length.
Heating and piercing: the billet is heated to about 1200 degrees Celsius, and then pierced through a pressure piercing machine.
Rolling or Extruding: Af ter perforation, the billet undergoes several rolling or extruding processes to form tubes.
Sizing: The pipe is sized by sizing machine to ensure its dimensional accuracy.
Cooling and Straightening: After sizing, the tubes are cooled in cooling towers and subsequently straightened.
Inspection and screening: internal defects are detected by metal flaw detector or hydraulic test, and strict manual screening is carried out.
Marking and warehousing: the surface of the pipe is sprayed with marking information such as specification and production batch number, and finally lifted into the warehouse.
| Feature | Cold Drawn Precision | Hot Rolled Seamless |
| Dimensional Tolerance | h8–h10 (±0.02–0.08mm) | ±0.5mm or wider |
| Surface Finish | Smooth, bright, scale-free (Ra 0.4–1.6μm) | Black oxide, rougher (Ra 6.3–12.5μm) |
| Machining Allowance | Minimal (0.2–0.5mm) | Significant (2–5mm typical) |
| Mechanical Strength | Higher yield and tensile due to work hardening | Standard as-rolled properties |
| Straightness | ≤0.5–1.0mm/m | ≤2–3mm/m |
| Best Application | Precision shafts, hydraulic cylinders, machined parts | General structural, low-tolerance piping |
Q1: What is the difference between SAE1045 and SAE1020 or SAE4140 seamless pipe?
A: SAE1045 is a medium-carbon steel (0.43–0.50% C) offering higher strength and hardness than low-carbon SAE1020, making it suitable for wear-resistant and heat-treatable components. Compared to alloy steel SAE4140, 1045 lacks chromium and molybdenum, so it does not achieve the same deep-hardening or high-temperature strength—but it is significantly more economical and machines more easily for general mechanical applications.
Q2: How does cold drawn precision pipe differ from hot rolled seamless pipe?
A: Cold drawn pipe is produced by pulling hot-rolled seamless tube through dies at room temperature. This process improves dimensional accuracy (h8–h10 tolerances), surface finish (Ra 0.4–1.6μm), and mechanical strength through work hardening. Hot rolled pipe is produced at elevated temperatures with looser tolerances and a rougher surface, suitable for general structural and fluid conveyance where precision is not critical.
Q3: Can SAE1045 cold drawn pipe be heat treated after delivery?
A: Yes. SAE1045 is specifically chosen for its excellent response to heat treatment. It can be through-hardened by quenching and tempering to achieve 28–34 HRC (normalized) up to 50–55 HRC (hardened), or induction-hardened on the surface for wear-resistant journals. We can supply pipe in the annealed condition for easier machining, or pre-hardened to your specified hardness range.
Q4: Is this pipe suitable for hydraulic cylinder barrels without further machining?
A: For many medium-duty hydraulic applications, our cold drawn pipe can be used directly or after light honing. The smooth internal surface (Ra 0.4–1.6μm) and tight wall tolerance provide an excellent starting point for cylinder manufacture. For high-pressure or precision servo cylinders, we recommend our additional honing or skiving-and-roller-burnishing service to achieve Ra 0.2μm and exact bore diameter.
Q5: What is your minimum order quantity (MOQ)?
A: Our standard MOQ is one metric ton per size. For trial orders or mixed-size shipments, we offer flexible arrangements starting from 500 kg. Full container loads (approximately 25 metric tons) qualify for our best mill-direct pricing.
