straight seam HF welded pipe mill introduction

The plate in certain width after slitting line and stripping is unfolded and leveled. Then, they are sent into forming machine. Used the roller, the plate is bent into pipe state. The edge of the steel plate is melted by making use of the proximity effect and skin effect of high frequency current. Then, the plate is extruded and welded into the pipe by extruding roller. Straight seam welded pipe mill also is called ERW mill.

The forming styles of straight seam welded pipe can be divided into roll forming, flexible forming, full auto flexible forming. The mill developed by our company adopts roll forming when having small diameter (Φ≤114). Flexible forming or full automatic flexible forming is adopted when having middle or large diameter(Φ≤711).

    In recent year, our company developed the precise control forming. The advantage of this kind forming is to guarantee the excellent forming quality in rough forming section through the precise control. Then it is no need to have the repair management in precise forming section. Therefore, the precise forming in this forming method does not need to change the roller. All the forming section does not need to change the roller, which solves the problem of the change in precise forming section and non-change in rough forming section. Therefore, it saves the roller investment and decreases the time of roller changing. Besides, during the diameter changing, all are controlled by industrial computer. The roller will automatically reach the position by inputting the pipe diameter, pipe wall thickness, material and other parameters. It largely improves the mill efficiency and pipe qualified rate. This forming method is suitable for medium and large mill from 219mm to 711mm, which saves the investment and improves the efficiency.

According to the pipe application, the ERW line can be divided to API standard pipe mill and national standard mill.

API standard straight seam HF welded pipe mill introduction is mainly used for producing the high grade pipe such as oil, gas delivering and casing pipe in the oil well. These high grade pipes strictly require the pipe material and pipe quality. This kind of straight seam HF welded pipe mill has IF annealing, air cooling roller rail, UT detector, high pressure hydrotester, diameter drifter and other detect equipments and art craft.

National standard mill is mainly used for manufacturing the low pressure fluid pipe and structure pipe.

     Straight seam welded pipe mill available models:                                         






Forming Speed(m/min) Steel thickness(mm) Capacity


1 HMZF-32 Φ15~Φ32 10~120 1.5~2.5 ~400 18×100
2 HMZF-50 Φ21~Φ50 10~120 2.0~4.0 ~450 18×100
3 HMZF-60 Φ25~Φ60 10~110 2.0~4.5 ~500 18×100
4 HMZF-76 Φ32~Φ76 10~110 2.0~5.0 ~550 18×120
5 HMZF-89 Φ36~Φ89 10~100 2.0~6.0 ~600 18×120
6 HMZF-114 Φ50~Φ114 10~90 2.0~9.0 ~700 18×120
7 HMZF-127 Φ50~Φ127 10~90 2.0~9.0 ~700 18×120
8 HMZF-140 Φ60~Φ140 10~90 2.0~10 ~750 18×120
9 HMZF-165 Φ76~Φ165 10~80 2.0~10 ~800 18×150
10 HMZF-219 Φ89~Φ219 10~60 3.0~14 ~1000 24×200
11 HMZF-273 Φ89~Φ273 10~60 3.0~14 ~1200 24×200
12 HMZF-325 Φ140~Φ325 10~40 4.0~16 ~2500 24×300
13 HMZF-355 Φ140~Φ355 10~40 4.0~16 ~2500 24×300
14 HMZF-406 Φ165~Φ406 8~30 4.0~16 ~3000 24×400
15 HMZF-426 Φ165~Φ426 8~30 4.0~16 ~3000 24×400
16 HMZF-508 Φ219~Φ508 8~30 4.0~20 ~5000 30×400
17 HMZF-610 Φ273~Φ610 8~30 4.0~22 ~7000 30×400
18 HMZF-630 Φ273~Φ630 8~30 4.0~22 ~7000 30×400
19 HMZF-660 Φ273~Φ660 8~30 4.0~25 ~7000 30×400
20 HMZF-711 Φ325~Φ711 8~25 5.0~25 ~10000 30×600


Production process:

     Loading coil – uncoiling – leveling – cutting and coil welding – accumulator and material storage – precise leveling – forming – high frequency welding – water cooling –online UT detector –  IF annealing – stable pipe pulling–  air cooling – water cooling – sizing – flying cut off – pipe end facing and beveling machine – hydrotester – offline UT welding seam and pipe inspection – weighting, measuring, spraying – pipe collection

32 HF welded pipe mill introduction

50 HF welded pipe mill introduction

60 HF welded pipe mill introduction

76 HF welded pipe mill introduction

89 HF welded pipe mill introduction

114 HF welded pipe mill introduction

127 HF welded pipe mill introduction

140 HF welded pipe mill introduction

165 HF welded pipe mill introduction

219 HF welded pipe mill introduction

273 HF welded pipe mill introduction

325 HF welded pipe mill introduction

355 HF welded pipe mill introduction

406 HF welded pipe mill introduction

426 HF welded pipe mill introduction

508 HF welded pipe mill introduction

610 HF welded pipe mill introduction

660 HF welded pipe mill introduction


711 HF welded pipe mill introduction