Introduction

In piping engineering design, do you always have to face the problem  how to choose mechanical joint or flange?  Today , for all the concerns, you will learn their mechanical properties , their usage scenarios and advantages and disadvantages .

Mechanical Joint

Mechanical joint is a kind of connecting device for pipe fittings,values and some pipelines.  Generally ,  there are gaskets between tow pieces, made of  rubber, silicone, or PTFE.

Installation

1. Sealing surface from pipe end to groove need to keep clean and smooth.
2. Width of sealing surface at pipe end need to meet the technical requirements.
3. Width and depth of groove need to meet the technical requirements.
4. Pipeline should keep concentric after installation.

Application

Mechanical joints are often used in some low-pressure pipelines due to their convenience, speed and competitive price.

Flange

A flange is a component that connects tow pipes, used for connecting pipe ends.  flange is  on the inlet and outlet of equipment for connecting two devices.

Installation

1. Before installation, you should check if flange including its material,size,sealing face and gasket meets design requirements.
2. When connecting flanges, must maintain the parallelism between the flanges ,It is not allowed to eliminate flange misalignment by tightening bolts.
3. The flange plane should be perpendicular to the pipe axis and impurities such as oxides should be removed.
4. Install flange gaskets, only one gasket can be placed at each interface, and it is not allowed to place double layers or misalignment.

Application

1. In mechanical engineering field,flange is the component to connect pipeline. It always used in  components such as compensator, to ensure the security and reliability of the connection.
2. In construction modeling field, flanges are often used in plumbing, HVAC systems, power systems, and more.
3. In the chemical industry, flanges are widely used. Because flange can withstand high temperature and corrosion to transport these special chemical media.

Mechanical Joint vs. Flange

Advantages of Mechanical Joint

1. Mechanical joint is sturdy and durable. It mainly made of carbon steel or stainless steel,  so it can effectively resist corrosion and oxidation, with a longer service life.
2. Mechanical joints have strong clamping force. It can be used to clamp pipes, valves, and other equipment by rotating screws  to ensure that they do not move or fall off due to force.
3. Mechanical joint installation is simple. The installation of the steel card is very simple. You don’t need professional tools and technical support, just use simple tools such as wrenches and screwdrivers to complete it.

Disadvantages of Mechanical Joint

Mechanical joints have poor shock proof and anti release performance.

Advantages of Flanges

1. Flange can bear high pressure.  It can ensure the normal operation of the equipment and the pipeline under high pressure.
2. Flange has better sealing performance. It can ensure the sealing performance, to  prevent fluid leakage or external impurities entering.
3. Flange is removable. So you can remove or replace, and its easy to maintain for the equipment .

 Disadvantages of Flanges

1. Higher cost.  Compared to others, flange may cost more, because of its raw materials and processes.
2. Professionals are required for the installation. If not installed properly, it may affect the use effect and safety of the equipment.

Conclusion

Choose mechanical joints or flanges based on different usage ranges and conditions.

When we use it in normal industrial pipeline connection that is low pressure and non flammable and explosive, or connecting the pipes that made of same material, which applied  in the normal media such as water or steam, you can choose mechanical joint.

When we use it in the  high level Industrial pipeline connection that is high pressure , flammable and explosive or connecting the pipes that made of different material or different diameter, which applied  in the media that is  high degree and pressure or flammable and explosive , you can choose flange.