What is a piling pipe?

Piling pipe is a kind of hollow steel pipe structure, which is usually used for bearing of foundation and supporting engineering. It can be used either as a steel pipe pile (directly as a bearing pile) or as a casing/casing (for drilling, pouring and temporary support). It is a common type of pile in modern foundation engineering, featuring high strength, strong adaptability and convenient construction.

Common types of piling pipes

A. Classification by production mode

1. Seamless steel pipe: Manufactured through hot rolling or cold drawing processes, without any welding seams.
· Features: High strength, excellent compressive and tensile resistance, and outstanding corrosion resistance, suitable for high-load and high-demand applications.

2. Resistance welded steel pipe (ERW/HFW) : A straight seam steel pipe that is welded by heating the edge of a metal strip with high-frequency induced current to partially melt it under mechanical pressure.
· Features: After the steel strip is uncoiled and formed, it undergoes high-frequency welding, resulting in a straight appearance, low production cost and high production efficiency. It is often used for medium and small diameter and economical piles.

3. LSAW steel pipe: The steel plate is welded by the straight seam submerged arc welding method.
· Features: Formed longitudinally from wide steel plates and welded by submerged arc welding, it is suitable for medium and large diameter and thick-walled pile pipes. The quality of the joint is high and it is suitable for occasions with high load-bearing requirements.

4. SSAW steel pipe: The weld seam is in a spiral shape.
· Features: The steel strip is formed by welding in a spiral shape, has a large diameter, is suitable for large-diameter long pipes, and has a relatively low cost. It is often used in docks, revetment piles, etc.

B. Classification by function/construction method

Pile driving: Directly drive in or vibrate in with a pile driver. This type of pipe pile needs to have sufficient strength and toughness.
Bored cast-in-place pile casing: Used as a casing, it supports the hole wall and serves as a conduit.
Rotary/impact piles: Depending on the differences in construction methods, the design of pile pipes may have different requirements (such as resistance to impact fatigue).

Manufacturing process of steel piling pipes

General manufacturing process: preparation of raw materials, forming, welding/pipe forming, heat treatment, straightening and fixed-length cutting, end treatment, non-destructive testing, mechanical testing and chemical analysis, internal and external anti-corrosion treatment, packaging and transportation.

Key points of seamless tube manufacturing: from piercing of cast billets or solid tube billets, hot rolling or cold drawing to dimensions; The key lies in the wall thickness and dimensional stability, as well as the metallographic and mechanical properties.
Key points of ERW manufacturing: The forming accuracy and alignment of steel strips, the control of welding current/frequency, post-treatment of weld seams (grinding, heat treatment), and weld flaw detection are very important.
Key points for LSAW/SSAW manufacturing: sheet/coil quality, welding current, interlayer compatibility between welding wire and weld seam, tempering/stress relief treatment of weld seam, flaw detection.

Application fields

· House construction

· Bridge construction

· Port and wharf engineering

· Construction of offshore oil and wind power facilities

· Retaining walls and supporting structures

· Earthwork support/temporary casing

· Environment and foundation reinforcement

Quality standards and specifications

ASTM series: For example, ASTM A252 (welded and seamless steel pipe piles) is often used for pile pipe standardization; There are also ASTM A53 (General Structural tubes), etc.

API/EN/JIS/GB/T: API (commonly used for oil and gas pipelines), EN (European structural pipe standards, such as EN 10219/10210 for related pipe materials), Japanese JIS and Chinese GB/T series (such as series standards for spiral welded pipes and straight seam welded pipes).

Examples of common engineering pile selection

For small and medium-sized buildings with shallow foundations: ERW steel pipe piles (economical and fast delivery).
High-load Bridges or offshore platforms: LSAW large-diameter/concrete-filled steel pipe composite piles (with high bearing capacity and durability).
For long single posts and coastal protection: SSAW (Spiral Submerged Arc) large-diameter piles (flexible in length and cost-effective).
Severe corrosion or high durability requirements: Seamless + anti-corrosion/concrete cast-in-place composite piles.

Why choose Central Steel?

Central Steel has been focusing on the steel pipe industry for many years and has rich experience in production and export. We specialize in the production and supply of a series of products such as Piling Pipe, Seamless Pipe, ERW Pipe, SSAW Pipe and LSAW Pipe.

The company is equipped with advanced production facilities and testing systems, and strictly manufactures and inspects in accordance with international standards such as ASTM, API, EN, and ISO.

Read more : What is steel sheet piling or Steel grades for piling pipe