Carbon Steel LSAW Pipe

Diameter

406mm- 1118mm (16 "- 44")

Thickness

6.0-25.4mm 1/4 "-1"

Standard

API,DNV,ISO,DEP,EN,ASTM,DIN,BS,JIS,GB,CSA

Length

5.8m,6m,12m,18m, ect.

Steel Grade

API 5L A- X70.

‌Comparison Dimension‌

‌LSAW (Longitudinal Submerged Arc Welded Pipe)‌

‌SSAW (Spiral Submerged Arc Welded Pipe)‌

‌Full Name‌

Longitudinal Submerged Arc Welded Pipe

Spiral Submerged Arc Welded Pipe

‌Raw Material‌

Single thick steel plate (thickness up to 50mm or more)

Hot-rolled steel strip (narrower width, flexible adjustment)

‌Forming Process‌

Plate pre-bent and formed via JCO/UOE method; seam runs parallel to pipe axis

Strip continuously spirally wound at an angle (typically 10°-30°); seam follows a helical path

‌Welding Method‌

Double-sided SAW, often with four-wire tandem welding; longitudinal straight seam

Double-sided SAW; continuous helical seam, 30%-100% longer than straight seam of equivalent length

‌Typical Diameter Range‌

Ф406.4mm - Ф1422.4mm

Ф 219 mm - Ф 2540mm

‌Typical Wall Thickness Range‌

8 mm - 50mm

6mm - 25mm (standard), up to 30mm with specialized processes

‌Pressure Rating‌

High pressure (≥10 MPa); suitable for X70-X120 high-grade steels; meets Class 1-2 area safety requirements

Medium to low pressure (typically ≤10 MPa); suitable for X60-X80 grades; commonly used in Class 3-4 areas

‌Geometric Accuracy‌

High (ovality ≤0.5%D, straightness ≤1.5 mm/m); stable dimensions after expansion

Lower; weld cap control critical (≤2.5 mm); prone to "saddle" or "fishback" internal weld profiles

‌Residual Stress‌

Uniformly distributed; largely eliminated by hydraulic expansion

Complex and uneven; predominantly tensile state

‌Weld Strength Characteristics‌

Shorter weld, fewer defects, lower stress concentration; higher burst pressure than SSAW

Helical seam disperses primary stress; superior crack arrest performance; failure confined to single pitch

‌Static Burst Strength‌

Higher yield and burst pressures; optimal for high-pressure, high-stress environments

Slightly lower burst pressure; superior ductility and crack propagation resistance

‌Primary Production Standards‌

API 5L, GB/T 9711, ASTM A671, ISO 3183

API 5L, GB/T 9711, ASTM A671, ISO 3183

‌Equipment Investment‌

High (requires large JCO/UOE presses, expansion machines)

Lower (simpler coiling equipment, reduced infrastructure cost)

‌Production Efficiency‌

Lower (single-plate processing, complex)

Higher (continuous strip feeding, ideal for high-volume production)

‌Typical Application Fields‌

Mainline oil/gas pipelines, subsea pipelines, arctic regions, urban dense zones, deepwater projects, high-pressure systems

Long-distance pipelines (non-high-pressure sections), water transmission, municipal networks, heating lines

‌Coating Compatibility‌

Fully compatible with 3PE, FBE, IPN8710; strong adhesion

Compatible with major coating systems; weld cap may affect uniformity, requiring special treatment

‌Typical Project Examples‌

West-East Gas Pipeline (X70, Φ1016 mm), Nord Stream, Gulf of Mexico deepwater pipelines

West-East Gas Pipeline Line IV (Φ1219 mm, X70), Guliang-Hekou connecting line (18 m ultra-long pipes), urban water networks