Common Types of Supports for Pressure Vessel

 
Pressure vessels play a crucial role in industrial production, and their installation and placement require careful attention, particularly the support sections that come into contact with the foundation plane. The supports are key load-bearing components, and their manufacturing quality, along with the assembly and welding quality to the vessel shell, directly affects the operational stability and safety of the pressure vessel. Furthermore, the assembly of the supports with the vessel shell typically occurs during the final assembly stage of the vessel, a process that directly impacts critical quality elements such as the orientation of the nozzles, elevation, and axis inclination. Therefore, the entire process of manufacturing and assembling the supports must be given adequate attention to ensure the reliability and stability of the equipment during use.

The Role and Importance of Supports

 
The primary function of supports is to hold the pressure vessel in place, ensuring the safety and stability of the equipment under various operating conditions. Depending on the vessel’s shape, size, working environment, and load, the type and design of the supports can vary. Proper design and installation of supports can effectively reduce vibrations and stress concentrations during operation, thereby enhancing the service life and operational safety of the equipment.

Common Types of Pressure Vessel Supports

 
When selecting supports for pressure vessels, understanding the common types and their characteristics is crucial. Different types of supports have distinct structural designs and applications, suitable for various shapes and sizes of vessels. The following sections provide detailed descriptions of several common support types and their applications to help you better understand their characteristics and selection criteria.

1. Saddle Supports

 
Saddle supports are widely used in medium to large horizontal pressure vessels and are named for their saddle-like shape. They are designed to closely fit the local outer wall of the vessel, providing stable support. Typically, horizontal equipment is supported by two saddle supports, but additional supports are required if the equipment is too long to be adequately supported by two. Saddle supports are mainly composed of saddle pads (reinforcement plates), webs, gussets, and base plates welded together. The pads are used to improve the local stress conditions of the equipment shell, allowing the saddle to evenly bear the vessel's load. The gussets enhance the rigidity of the supports, ensuring that the equipment can effectively transmit compressive forces and resist external bending moments during operation, preventing deformation or damage to the equipment.

2. Leg Supports

 
Leg supports, often referred to as legs, are primarily used for vertical equipment but can also be used for certain horizontal equipment. The design is simple, consisting of a base plate, a cap plate, and columns welded together. The base plate has bolt holes for securing the equipment to the foundation. Typically, three leg supports are evenly distributed around the equipment to ensure balance and stability. For larger equipment, four leg supports may be used to provide better support. Leg supports are categorized into angle iron column type, steel tube column type, and H-shaped column type based on the column material and structure, with each type having variants with or without pads, resulting in a total of six types. These supports are suitable for applications requiring the equipment bottom to be relatively close to the ground and needing simple support.

3. Lug Supports

 
Lug supports, also known as hanging supports, are usually used for equipment that needs to be suspended. Depending on the arm length, lug supports are divided into short arm, long arm, and extended arm types, with each type available with or without pads. Long arm and extended arm lug supports are commonly used when the vessel is insulated or needs to be placed directly on a floor. The advantage of this type of support is its simple installation and high flexibility, making it suitable for various installation conditions.

4. Bracket Supports

 
Bracket supports are typically used as support structures on the bottom or lower outer wall of vessels, securing the equipment by welding several columns or support plates. The columns can be made of round pipes or shaped steel welded to the base plate, while the support plates are formed by welding two gussets to the base plate. This design effectively reduces local stress at the bottom of the vessel and enhances the support’s load-bearing capacity and stability. Pads are usually welded at the connection points between the supports and the vessel shell to reduce local stress concentration. Bracket supports are simple and lightweight and do not produce eccentric moments, making them very suitable for small vertical or horizontal vessels. However, due to higher local stress, these supports may not be suitable for all applications, especially where the bottom of the vessel is close to the ground.

Considerations for Choosing Supports

 
Selecting supports for pressure vessels requires a comprehensive consideration of several factors, including the type, size, working environment, load distribution, and installation space of the vessel. Each support type has its unique advantages and applicable scenarios. Proper selection and design can not only enhance the operational stability of the equipment but also extend its service life.

1. Equipment Type and Size

 
For medium to large horizontal vessels, saddle supports are usually chosen; for large tower-type vessels, skirt supports are commonly used. Smaller vessels may use bracket supports, lug supports, or leg supports.

2. Working Environment and Load Distribution

 
If the equipment needs to withstand large dynamic loads or frequent vibrations, supports with higher rigidity and better stability, such as saddle or leg supports, may be required.

3. Installation Space and Conditions

 
In cases where installation space is limited or suspension installation is needed, lug supports and bracket supports may be more suitable.
 
In conclusion, pressure vessel supports play an indispensable role in the installation and use of the equipment. Different types of supports are selected based on the characteristics of the pressure vessel, the operating environment, and operational requirements. Proper design and installation of supports can significantly enhance the safety and stability of the equipment. Understanding the features and applications of various supports helps optimize the operational performance of the equipment, ensuring the reliability and safety of pressure vessels in use.