Pipe

Pipe is a tubular production made for sale as a production item. Cylinders formed from plate during the fabrication of auxiliary equipment are not pipes. Cold expanded pipe is seamless or welded pipe that is formed and then cold expanded while in the pipe mill so that the circumference is permanently increased by at least 50 percent.


Steel Pipe (Carbon Steel)

By common custom, steel is considered to be carbon steel when no minimum content is specified or required for aluminum, boron, chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium, zirconium or any other element added to obtain a desired alloying effect, when the specified minimum for copper does not exceed 0.40 percent or when the maximum content specified for any of the following elements does not exceed the following percentages: Copper 0.60 percent, manganese 1.65 percent and silicon 0.60 percent. In all carbon steels, small quantities of certain residual elements unavoidably retained from raw materials are sometimes found but are not specified or required, such as copper, nickel, molybdenum, chromium etc. These elements are considered as incidental and are not normally determined or reported.


Alloy Steel

By common custom, steel is considered to be alloy steel when the maximum of range given for the content of alloying elements exceeds one or more of the following limits, copper 0.60 percent, manganese 1.65 percent, silicon 0.60 percent, or in which a definite range of a definite minimum quantity of any of the following elements is specified or required within limits of the recognized field of constructional alloy steels: aluminum, boron, chromium (up to 3.99 percent), cobalt, columbium, molybdenum, nickel, titanium, tungsten, vanadium, zirconium or any other alloying element added to obtain a desired alloying effect. Small quantities of certain elements are unavoidably present in any alloy steels. In many applications, these are not considered to be important and are not specified or required. When not specified or required they should not exceed the following limit: Chromium (0.20 percent), Copper (0.35 percent), molybdenum (0.06 percent), nickel (0.25 percent).


Electrical-resistance welded pipe ERW)

ERW pipe is produced in individual lengths or in continuous lengths from coiled skelp and is subsequently cut into individual lengths. The resulting lengths have a longitudinal butt joint, where in coalescence is produced by the heat obtained from the resistance of the pipe to the flow of electric current in a circuit of which the pipe is part and by the application of pressure, Typical specifications are ASTM A53, ASTM A 135 and API5L.


Furnace Butt-welded pipe

i. Butt-welded is furnace welded pipe produced in individual lengths from cut-length skelp. The pipe's longitudinal butt joint forge welded by mechanical pressure is developed in drawing the furnace-heated skelp through a cone-shaped die (commonly known as a “welded bell”) which serves as a combined forming and welding die. Typical specifications are ASTM A53 and API 5L.
ii. Continuous-welded is furnace welded pipe produced in continuous lengths from coiled skelp and is subsequently cut into individual lengths. The pipes longitudinal butt joint is forge-welded by the mechanical pressure developed in rolling the formed skelp through a set of round pass welding rolls typical specifications are ASTM A53 and API 5L.


Electrical-fusion-welded pipe

It is a type of pipe having a longitudinal butt joint wherein coalescence is produced in the performed tube by manual or automatic electric are welding. The weld may be single or double and may be made with or without the use of filler metal. Typical specifications are ASTM A 134 and ASTM A 139, which permit single or double weld with or without the use of filler metal. Additional typical specifications are ASTM A 672, which require both inside and out side welds and the use of filler metal.


Spiral-welded pipe

This type of pipe is also made by the electric fusion-welded process with either a butt joint, a lap joint or a lock-seam joint. Typical specifications are ASTM A 134, ASTM A 139 (Butt joint), API 5L and ASTMA 211 (butt joint, lap joint, or lock steam joint).


Electric-flush-wedded pipe

It is a type of pipe having a longitudinal butt joint, where in coalescence is produced simultaneously over the entire area of abutting surfaces by the heat obtained form resistance to the flow of electric current between the two surfaces and by the specification of pressure after heating is substantially completed. Flashing and upsetting are accompanied by expulsion of metal from the joint. A typical specification is API 5L


Double Submerged Are Welded Pipe (DSAW)

This is a type of pipe which has a longitudinal butt joint produced by at least two passes, one of which is on the inside of the pipe. Heating with an electric arc or arcs between the bare mental electrode or electrodes and the work produces coalescence. The welding is shielded by a blanket or granular, fusible material on the work. Pressure is not used and filler metal for the inside and outside welds is obtained from the electrode or electrodes. Typical specifications are ASTMA 381 and API 5L.


Seamless Pipe

Seamless pipe is wrought tubular product made without welded seam. It is manufactured by hot working steel and if necessary by subsequently cold finishing the hot-worked tubular product to produce designed shape, dimensions and properties. Typical specifications are ASTM A 53, ASTM A 106 and API 5L.