Marzogh logo


free consultation

Working hours: 08:30 am to 13:00 pm and 14:00 pm to 17:30 pm

Iraq- baghdad

kradeh inside, near babel, hotel Jamrh complex, 3rd floor





Certainly, one of the most efficient and natural simple machines must be the pipe. A pipe is a hollow cylinder of metal, wood, or other material used for the transferring of water, gas, steam, petroleum, and so on. A pipe is a pervasive product in the industrial, commercial, and residential industries.  Pipes are sometimes referred to as tubes. The main difference between them is that pipe is specified by nominal size and schedule, but tube is specified by the outside diameter (OD) and a wall thickness.

Generally, a pipe is introduced by 7 main parameters:

  1. Type
  2. Size
  3. Material
  4. Dimensional standards
  5. Thickness
  6. Pipe ends
  7. Length                 

  1. Type

Generally, the two types of the pipe are welded and seamless.

Welded pipe:

In a welded pipe, a long ribbon of steel is trimmed to the desired length and a flat rectangular sheet is produced. The rectangular sheets are fed through a rolling machine that curls the longer sides up toward one another, forming a cylinder. In the ERW process, high frequency current is passed between the edges, making them to melt and fuse together.

There are 4 common methods of the welding of the pipe:

  • Electrical Resistance Welding (ERW)
  • Furnace Butt Welding (FBW)
  • Electrical Fusion Welding (EFW)
  • Submerged Arc Welding (SAW)

Seamless pipe:

A seamless pipe is produced by piercing a billet followed by rolling or drawing or both to the desired length. Therefore, a seamless pipe does not have a welded joint in its cross section.

  1. Size

The sizes of the pipe are determined by two numbers: diameter and thickness

In the US, pipe is determined by 2 non-dimensional numbers: nominal pipe size (NPS) and schedule (SCH).

Nominal pipe size (NPS) is used to describe a pipe by its name. NPS is generally associated with the inside diameter (ID) for sizes 1.8 to 12, and NPS is equal to the outside diameter (OD) in inches for the sizes 14 and beyond.

Schedule (SCH) refers to the wall thickness of the pipe. As the schedule number increases, the wall thickness increases, and the inside diameter (ID) is decreased.

3. Material

Based on the ASTM (American society of testing and material), the materials of the pipe can be categorized as metal and non-metal.

Metal materials

Metal materials can be categorized as ferrous and non-ferrous materials.

Ferrous materials: iron is the main constituent element in these materials. Some of them are:

Carbon steel

Carbon steel is used in the great majority of the piping. Based on the amount of carbon, it is classified as:

Low carbon steel (less than 0.1% carbon)

Mild carbon steel (up to 0.3% carbon)

Medium carbon steel (0.3 to 0.6% carbon)

High carbon steel (over 0.6% carbon)

Stainless steel

Stainless steel pipe are used for different reasons:

  • to resist corrosion and oxidation
  • to resist high temperatures
  • for cleanliness and low maintenance costs
  • to maintain the purity of materials which come in contact with stainless

The ability of stainless steel to resist corrosion is obtained by adding a minimum of 12% chromium to the iron alloy.

Alloy steel

Nickel Steels : These steels contain from 3.5% nickel to 5% nickel.

Chromium Steels: An addition of up to 9% Chromium combats the tendency to oxidize at high temperatures and resists corrosion from sulfur compounds. Stainless Steels contain at least 10.5% Chromium.

Chrome Vanadium Steels: Steels of this type contain from 0.15% to 0.25% vanadium, 0.6% to 1.5% chromium, and 0.1% to 0.6% carbon.

Manganese Steels: Larger amounts (between 2% and 10%) produce somewhat brittle steel, while still larger amounts (11% to 14%) produce steel that is tough and very resistant.

Cast iron: Cast iron is any iron containing greater than 2% carbon. The high carbon content makes it extremely hard and brittle. Cast iron has a high compressive strength and good wear resistance.

Galvanized steel: Galvanized iron pipe (GI) is a regular iron pipe that is coated with a thin layer of zinc. The zinc greatly increases the life of the pipe by protecting it from rust and corrosion.

Non-ferrous materials: iron is not the main element in these materials. They are usually made of aluminum, copper and etc. such as:

Aluminum and aluminum alloy

Copper and copper alloy

Nickel and nickel alloy

Titanium and titanium alloy

Non-metal materials: these materials are used for their light weight, chemical resistance, non-corrosive properties, and ease of making connections. They are mostly used in water industry and drainage systems. Non-metal materials include polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), fiber reinforced plastic (FRP), polypropylene (PP), polyethylene (PE), cross-linked high-density polyethylene (PEX), and etc.

  1. Dimensional standards

Pipe sizes are documented by a number of standards, including API5L, ANSI/ASME B 36.10M in the US, and BS 1600 and BS 1387 in the United Kingdom.

  1. Thickness

The distance between inside diameter (ID) and outside diameter (OD) is called thickness.

6. End preparation

There is a direct relationship between the two pipe’s connection and the end preparation of the pipe. The steel pipes are categorized to three types based on their specific end preparation:

  1. Plain ends (PE)
  2. Bevel ends (BE)
  3. Threading ends (TE)

 Plain Ends (PE)

Plain end pipe is a pipe that has been trimmed to 90° perpendicular to the pipe run. This type of end is needed when two pipes join to each other by mechanical couplings, socket weld fittings, or slip on flange.

 Bevel Ends (BE)

This type of end is formed when a surface of the pipe is not at a right angle (perpendicular) to another surface. The standard angle on a pipe bevel is 37.5°. The experts use this type of the end for Butt welding.

Threading Ends (TE)

Typically, it is used on pipe 3 and smaller. Threaded connections are referred to as screwed pipe. Due to the tapered grooves cut into the ends of a pipe, screwed pipe and screwed fittings can easily be assembled without welding.

  1. Length

Pipe is supplied in Random length (18 to 25 ft) or double random length (38 to 48 ft).


With the above explanations, we have completely realized that the pipes in different dimensions and materials depend on the kind of executive projects. But the significant point is that Marzogh Company has more than one design project and the implementation of mini-petrochemical and petrochemical in Iraq and Iran and an ongoing project in Afghanistan. Marzogh Company does not apply any ordinary material. If you use the ordinary material, you will definitely observe the lack of the quality of equipment in the production process. Marzogh Company possesses a specialized board in connection and piping. It is the provider of the main parts of the popular and valid brands in the world at a reasonable price. It gives the opportunity for its customers to choose high-quality products in petrochemical parts and equipment in the production for many years. Stay tuned.

Leave an answer

Your email address will not be published.

Last articles
Last comments