High frequency straight seam welded pipe unit
This production line is a specialized equipment for producing
straight seam welded pipes in industries such as metallurgy,
petroleum, construction, transportation, machinery, and vehicles.
It uses hot-rolled steel strips as raw materials and produces round
and rectangular pipes of the required specifications through cold
bending and high-frequency welding methods.
This production line adopts mature, reliable, complete, and
economically applicable production processes to ensure that the
physical quality, cost, and various consumption indicators of the
products reach a relatively advanced level. The products produced
have strong competitiveness in terms of quality and price.
Production line process flow:
Raw material (strip steel coil) → uncoiling → storage → passive
leveling → forming and rolling → high-frequency welding → removal
of external burrs → zinc replenishment → spray cooling → sizing and
shaping → rough straightening → cutting to length → pipe collection
and bundling.
Straight seam submerged arc welded pipe unit
It is to open and level a steel plate of a certain width after
longitudinal cutting and slitting, and then enter the forming
machine. The fully automatic and accurate control flexible forming
is used, and the steel plate is bent into a circular pipe using
rollers. The steel pipe is pre welded using gas shielded welding.
Then cut off and perform submerged arc welding on the inner and
outer welds of the steel pipe offline. After water pressure
testing, flat head chamfering, weld seam and pipe body inspection,
qualified submerged arc welded pipes are obtained.
Technical Specifications
| Model | Round Pipe (mm) | Square Pipe (mm) | Thickness (mm) | Speed (m/min) |
|---|
| DRC-12 | Φ4-Φ12 | / | 0.2-0.5 | 120 |
| DRC-16 | Φ6-Φ16 | / | 0.2-0.8 | 120 |
| DRC-20 | Φ8-Φ20 | 6x6-15x15 | 0.3-1.0 | 120 |
| DRC-25 | Φ10-Φ25 | 7x7-19x19 | 0.3-1.5 | 120 |
| DRC-32 | Φ12-Φ32 | 9x9-25x25 | 0.5-2.0 | 120 |
| DRC-50 | Φ20-Φ50 | 15x15-39x39 | 0.8-3.0 | 120 |
| DRC-76 | Φ32-Φ76 | 25x25-59x59 | 1.2-4.0 | 120 |
| DRC-89 | Φ42-Φ89 | 35x35-70x70 | 1.5-4.5 | 110 |
| DRC-114 | Φ48-Φ114 | 40x40-90x90 | 1.5-4.5 | 70 |
| DRC-140 | Φ60-Φ140 | 50x50-110x110 | 2.0-5.0 | 60 |
| DRC-165 | Φ76-Φ165 | 60x60-130x130 | 2.0-6.0 | 55 |
| DRC-219 | Φ89-Φ219 | 70x70-170x170 | 2.0-8.0 | 50 |
| DRC-273 | Φ114-Φ273 | 90x90-210x210 | 3.0-10.0 | 45 |
| DRC-325 | Φ140-Φ325 | 110x110-250x250 | 4.0-12.7 | 40 |
| DRC-377 | Φ165-Φ377 | 130x130-280x280 | 4.0-14.0 | 35 |
| DRC-406 | Φ219-Φ406 | 170x170-330x330 | 6.0-16.0 | 30 |
| DRC-508 | Φ273-Φ508 | 210x210-400x400 | 6.0-18.0 | 25 |
| DRC-660 | Φ325-Φ660 | 250x250-500x500 | 6.0-20.0 | 20 |
| DRC-720 | Φ355-Φ720 | 300x300-600x600 | 6.0-22.0 | 20 |
Size Range by Application
| Usage | External Diameter (mm) | Weight (mm) | Length (m) |
|---|
| Oil and gas pipelines | 406 - 1524 (16" - 60") | 6 - 40 (1/4" - 1.57") | 8 - 12.1 |
| Construction (pipe pile) | 350 - 1600 (14" - 63") | 6 - 60 (1/4" - 2.36") | 6 - 12 |
| Rolling tube | 1200 - 3800 (47.24" - 150") | 12 - 120 (1/2" - 4.7") | ≤3.2 |
Custom specifications available according to customer requirements

Application Scope
Specialized equipment for producing straight seam welded pipes in
industries including metallurgy, petroleum, construction,
transportation, machinery, and vehicles.

Customer Factory Inspection

Frequently Asked Questions
What information do we need customers to provide?
Duolek has an R&D Center focused on product development. We can
design and modify products according to customer requirements,
maintaining an open approach to customer service.
What's your quality control system?
We operate an ISO9001 Quality Management System. Our quality
control includes materials inspection, machining process control,
finished product testing, and pre-shipment inspection. Each step
has dedicated inspectors with recorded test results.
What payment terms do you accept?
We prefer bank transfer (T/T): 30% deposit with order confirmation
and 70% before shipment. Letters of Credit (L/C) are accepted for
orders over $200,000 USD.
What is your warranty policy?
All products carry a one-year warranty from delivery date against
defects in materials and workmanship. Normal wear and tear are not
covered.