How to Connect Steel Pipe?

The time of issue:2013-12-24 9:02:09       Author:

API steel pipes with high-quality carbon steel or alloy steel, hot-rolled, cold-rolled (pull) of the points. Welded steel pipes' welding process divided them into different stove pipe, welded (ERW) pipes and automatic arc welded pipe, welded its different forms includes Longitudinal and spiral welded pipe, its shape is divided ends circular welded and shaped (square, flat, etc.) pipe.

There are different ways to connect API steel pipes:
1. API steel pipes connection can be divided into: light pipe (pipe end without thread) and threading pipe (pipe with threaded ends).
2. Car wire tube is divided into: general threading pipe and pipe threading pipe end upsetting.
3. Thick threading pipe can be divided into: EUE (with external thread), the thickening (with female thread) and internal and external thickening (with external threads), etc. threading pipe.

Welding: the model chosen according to design requirements, must have quality certificates. The welding rod use structural steel welding rod, Low-alloy structural steel welding rod, and Should adopt a low hydrogen electrode (alkaline electrode) welding important structures. After then, baking instructions as required into the cooler, used with the check.

General process: Ambient temperature is below 0 ℃, preheating, hot temperature should be determined according to the process of testing. Job preparation → arc welding (welding, vertical welding, horizontal welding, overhead welding) → weld inspection

Example: flat welding (slightly different from other similar ).
1. Preparatory work: the selection of qualified welding , cleaning weld.
2. Welding current: according to the thickness of the welding, welding level electrode type, diameter, skilled welders and other factors, the appropriate choice of the welding current.
3. Pyrophoric arc: Landing point arc fillet weld ends should be, should be greater than 10mm, not just arcing, sparking arc immediately after the rod is pulled away from the weld area, so that member remains between the electrode and produce 2 ~ 4mm gap arc. Butt welds and fillet combination of timely access weld seam at both ends of the arc set off plates must be welded to the weld zone in the arc after arc board, should be in the middle of the weld joint front connector 15 ~ 20mm at the rear arc ignition, preheat the welding weldment. Then back to the start of the weld, the weld pool to fill the required thickness before welding forward.
4. Welding speed: Requires constant welding, ensure that the weld thickness, width uniform mask from molten iron and slag bath to see remain equidistant (2 ~ 3mm) is appropriate.
5. Welding electricity arc Length: according to different models and determine welding, arc length generally require steady, acid electrode is generally 3 ~ 4mm, alkaline electrode is generally 2 ~ 3mm appropriate.
6. Welding angle: According to the determination of the thickness of the two weldments, welding angle has two aspects, one is the angle between the direction of the welding electrode is 60 ~ 75 °; Second, the angle between the electrode and the weld around, there are two cases when the weldment when equal thickness, welding and welding pieces of angle are 45 °; weldment when unequal thickness, welding thicker weldments should be greater than the angle between the side electrode with thin weldments side angle.
7. Ending arc: Each weld to the end, after the crater should be filled, in the opposite direction to the direction of welding with arc, so that the weld crater thrown inside, to prevent crater bite of meat. Welding is completed, should be removed arc torch cutting board and grinding smooth, and not with a hammer shot down.
8. Cleaning residue: After clearing the entire weld slag, by welders self-test (including appearance and weld size, etc.) are free from problems only after transfer locations continue welding.
Under the same conditions other connection methods, under the same conditions, different sizes of the arc, the welding angle are different etc..

Connect API steel pipes, notice product protection, quality assurance and records, technical personnel safety measures and fire safety measures. The welded steel pipe and black steel pipe are also available.

More Steel Pipe Products, Please Click:

ERW Steel Pipe

Tubing

Reducer

• Prev:ERW Steel Pipe and LSAW Steel Pipe
• Next:The Secrets of API Steel Pipe