Non Metallic Coatings Q235 Q345 L175 Welded Steel Pipe

Non Metallic Coatings Q235 Q345 L175 Welded Steel Pipe

Welded Pipes Finishing
The finishing of welded pipes depends on customer requirements and applications. These include threaded and coupled ends for use in long fluid transportation lines, threaded end without coupling for diverse diameter lines, Plain End or Cut Square for the general purposes. Pipes with pre-grooved or bevelled end are supplied for structural applications.
A different metallic coating like galvanising, lead lining, aluminising and claddings are also used for corrosion protection during applications. Non-metallic coatings such as oiling, paints, plastic coating, coal tar etc are also used for protection during storage and transportation. End finishing and coatings add significant costs to the welded pipes.

Designations and Specifications
ASTM A53 and API-5L are commonly used to define general specifications of welded pipes. ASTM B36.10 standard is used to define sizes and dimensions of pipes and tubes. While some of the industries have their own norms and custom sizes.
In North America, designations used to define pipes sizes are known as Nominal Pipe Size (NPS) and Schedule Number (Sch.). NPS defines the internal diameter of pipes and Sch. refers to the range of wall thickness.
In European standards, Nominal Bore (NB) is used to represent the internal diameter in mm and OD represents the outer diameters of pipes and tubes. ASTM/ANSI standard weights are usually expressed in Kg/m or lb/ft.

The following length standards are used in the market and are vital for the pipeline project designs.
1. Single random length (SRL) ranges between 18 – 25 feet plain end or 18 – 22 feet threaded and coupled pipes.
2. Double random length (DRL) ranges between 38-40 feet.
3. Longer than double random is more than 38 – 40 feet in length.
4. Cut Lengths are produced in fixed lengths within +/- 1/8 inch, while some are produced up to 80 feet long.