SCH 80 pipe reducer

What is a pipe reducer?

Pipe reducers are also called reducing straight-through, reducing short pipes, and are commonly known as steel butt welding large and small heads. They are a type of steel butt welding pipe fittings. They are used to connect two different diameter pipes. The role of transition between caliber pipe welds. It is divided into two categories: concentric large and small heads and eccentric large and small heads. SCH 80 refers to the wall thickness of the reducer.

What is SCH 80?

SCH 80 (Schedule 80) represents the wall thickness, which refers to XS thickened pipes with a pressure wall thickness less than DN200mm. Usage scenarios generally involve high temperature, high pressure, and highly corrosive conditions. The wall thickness of SCH 80 grade pipes is relatively thick, and the pressure and temperature in the use environment must comply with ASME/ANSI standards to ensure the safety and reliability of the pipeline system. SCH 80 grade piping systems are often used in the manufacture of chemical equipment, high-pressure pipelines, high-temperature heaters and some special piping systems. When designing and installing a steel pipe system, it is necessary to select the appropriate pipe number according to the actual use environment to ensure the stability and safety of the pipeline system.

Standard specification for SCH 80 pipe reducer:

The standard specification for SCH 80 carbon steel pipe fittings is an important guarantee for ensuring the safety and quality of pipeline system operations. Various standard-setting organizations at home and abroad have formulated corresponding standards, such as the international pipe fitting standard ASME B16.9, the domestic steel pipe fitting standard GB/T12459, etc. There are corresponding regulations on the specifications, dimensions, surface treatment, pipe wall thickness, etc. of pipe fittings.

The internationally accepted pipe flange standards can be summarized into two different and non-interchangeable pipe flange systems: one is the European pipe flange system represented by Germany; the other is the American pipe flange system represented by the United States. 

How many types of steel pipe reducers are there? What are the process differences?

Classification of pipe reducer shapes:
(1) Concentric large and small heads. The large and small heads with the center of the circle on a straight line are called concentric large and small heads.
(2) Eccentric large and small heads refer to the large and small heads where the center of the circle is not on the same straight line. Its function is to run pipelines against the wall or the floor without taking up space, and to connect two pipes of different diameters to change the flow rate.
(3) Clamp-type large and small heads are mostly used to quickly connect the large and small heads with clamps, and are suitable for medium and low-pressure fire-fighting water conservancy pipelines.
(4) The size of the thread (thread) is divided into three types: internal and external threads, or internal and external threads.
(5) Socket-type heads: generally forged or forged high-pressure thick-walled heads.
(6) Grooved large and small heads: mostly used for grooved connection of reducers for fire protection pipelines.

How to make a SCH 80 pipe reducer？

The SCH 80 pipe reducer (large and small heads) is a pipe fitting used at the pipe diameter reduction point. The commonly used forming processes are mainly diameter reduction pressing, diameter expansion pressing, or diameter reduction plus diameter expansion pressing. For certain specifications of reducers, stamping can also be used.

1. Diameter reduction/diameter expansion forming
The reduction forming process of the reducer is to put a tube blank with the same diameter as the large end of the reducer into the forming mold, and by pressing the tube blank along the axial direction, the metal moves along the mold cavity and shrinks to form. According to the size of the reducer, it is divided into one-time press forming or multiple press forming.

Diameter expansion forming is to use a tube blank that is smaller than the diameter of the large end of the reducer, and use an inner punch to expand the diameter along the inner diameter of the tube blank. The diameter expansion process mainly solves the problem that the reducer with a larger diameter cannot be easily formed by diameter reduction. Sometimes, the diameter expansion and diameter reduction methods are combined according to the material and product forming needs.

During the deformation and pressing process of diameter reduction or expansion, cold pressing or hot pressing is determined according to different materials and diameter reduction conditions. Under normal circumstances, cold pressing should be used as much as possible, but hot pressing should be used when multiple diameter changes cause severe work hardening, when the wall thickness is too thick, or when alloy steel materials are used.

2. Stamping forming
In addition to using steel pipes as raw materials to produce reducers, some specifications of reducers can also be produced using steel plates using the stamping forming process. The shape of the punch used for drawing is designed with reference to the inner surface dimensions of the reducer, and the punch is used to punch and stretch the blanked steel plate into shape.

3. Steel plate rolling and forming
After using the steel plate for fan-shaped blanking, the large and small heads are rolled into large and small heads, and then butt welded. This process is mostly suitable for the production of large-diameter reducers, such as 1 meter to 6 meters in diameter. head.

4. High pressure forging large and small heads

Forged small and large heads are integrated reducers forged directly from round steel and steel ingots. Generally, socket pipe fittings and alloy high-pressure small and large heads are suitable for this process. This type of reducer is mostly used in high-pressure pipelines that require high wall thickness, pressure and sealing performance, such as steam pipelines, boiler pipes, nuclear power pipelines, etc.

Quality control of pipe reducer fittings:
Quality control of pipe reducer fittings is the key to ensuring the quality and safety of the pipeline system. The quality inspection of pipe fittings includes appearance quality inspection, chemical composition analysis, physical performance testing, non-destructive testing and other aspects. Only pipe fittings that have passed the inspection can be put into use to ensure the safe and effective operation of the pipeline system.

SCH 40 pipe vs SCH 80 pipe reducer fittings:
The main difference between SCH 40 and SCH 80 pipe reducer fittings is the wall thickness. SCH 40 pipe has a thinner wall thickness and is often used in low-pressure applications such as residential plumbing or irrigation systems. SCH 80 pipe elbow fitting has thicker walls and is used in high-pressure applications such as industrial processes, hydraulic systems and underground piping. They are designed to handle higher pressures and withstand greater stresses than SCH 40 pipe.

Looking at specific dimensions, the wall thickness of SCH 40 pipe is approximately 0.109 inches, while the wall thickness of SCH 80 pipe is approximately 0.154 inches. This means that SCH 80 pipe is approximately 30% thicker than SCH 40 pipe. While SCH 80 pipe is stronger and more durable than SCH 40 pipe, they are also more expensive.

SCH 80 pipe has thicker walls and requires more material and more manufacturing time, which increases costs. When selecting pipe for a specific application, it is important to consider the pressure requirements and the cost-effectiveness of selecting thicker, more expensive pipe.

Read more: Pipe reducer size selection