In the modern industrial field, pipeline systems are like the blood vessels of the human body, undertaking the crucial task of transporting various media. Whether in the power, chemical, petroleum, or other industries, the safe and stable operation of pipeline systems is of vital importance. Among the many devices that ensure the stability of pipeline systems, spring supports and hangers play an irreplaceable role, worthy of being called the "stabilizing guardians" of industrial pipeline systems. Next, let's delve into the mysteries of spring supports and hangers.
1. Working Principle of Spring Supports and Hangers
Spring supports and hangers are mainly designed based on the principle of moment balance. Within the specified load displacement range, the load moment and the spring moment always maintain a state of balance. When pipelines or equipment produce displacement due to factors such as thermal expansion, vibration, or external forces, spring supports and hangers can automatically adjust the supporting force through the expansion and contraction of their own springs, thereby providing stable support for pipelines and equipment.
Take thermal expansion as an example. Many industrial pipelines, when transporting high-temperature media, will undergo thermal expansion due to temperature rise, resulting in an increase in pipeline length and displacement. If rigid supports and hangers are used, the thermal expansion displacement of the pipeline will be restricted, generating huge stress inside the pipeline, which may lead to serious problems such as pipeline deformation, leakage, or even rupture. However, spring supports and hangers allow the pipeline to displace freely within a certain range, and at the same time, compensate for the displacement through the elastic deformation of the spring, maintaining stable support for the pipeline, effectively avoiding the generation of additional stress, and ensuring the safe operation of the pipeline system.
2. Types of Spring Supports and Hangers
There are various types of spring supports and hangers, and the common ones can be divided into two major categories: variable spring supports and hangers, and constant force spring supports and hangers.
(1) Variable Spring Supports and Hangers
Variable spring supports and hangers are mainly composed of cylindrical helical springs, displacement indicator plates, shells, and adjusting nuts and other components. When the pipeline system produces vertical displacement, the spring will compress or extend accordingly, causing the force at the fulcrum to change, and the load of the pipeline system at the fulcrum will be redistributed to nearby fulcrums. Usually, the load change rate of variable spring supports and hangers is specified within a certain range, generally 25%.
According to different installation methods, variable spring supports and hangers are further divided into seven types: A, B, C, D, E, F, and G.
Type A - Upper Thread Suspension Type: One end of the upper suspension rod is connected to the root, and the other end is screwed into the screw hole of the top plate of the spring support and hanger through threads and locked with a nut. The lower end of the turnbuckle is connected to the upper end of the pipeline suspension rod through threads. By rotating the turnbuckle, the pipeline can be hoisted to the specified installation position, and finally locked with a nut.
Type B - Single Ear Suspension Type and Type C - Double Ear Suspension Type: The upper ends of these two types of spring supports and hangers are connected to suspension rods or hanging plates, and the other ends of the suspension rods and hanging plates are rooted on steel beams or floor slabs. Other installation operations are similar to those of Type A.
Type D - Upper Adjustment Resting Type: The spring support and hanger are fixed on the steel beam or floor slab with bolts. The suspension rod passes through the hanger body and is connected to the pipeline. The top nut can be rotated to hoist the pipeline to the specified installation position, and then locked with a nut.
Type E - Lower Adjustment Resting Type: The spring support and hanger are also fixed on the steel beam or floor slab with bolts, and the installation method is similar to that of Type A.
Type F - Supporting Resting Type: The bottom plate of the spring support and hanger is fixed on the foundation, steel beam, or floor slab with bolts, and the top is used to support horizontal pipelines or the bottom of bends. When there is a difference between the actual on-site support height and the designed installation height, the load column can be rotated for fine adjustment, and the fine adjustment amount varies for different types of springs.
Type G - Parallel Suspension Type: By rotating the turnbuckle, the suspension rod fixed on the steel beam or floor slab is tightened, and after adjusting the hanger to the designed installation height, the turnbuckle is locked with a nut.
(2) Constant Force Spring Supports and Hangers
Constant force spring supports and hangers are mainly composed of cylindrical helical springs, fixed frames, rotating frames, motion mechanisms, adjusting devices, spring sleeves, etc. Their notable feature is that when the pipeline system displaces up and down (vertically), the load remains unchanged, and theoretically, the load change rate is zero. This makes constant force spring supports and hangers particularly suitable for pipeline systems with large vertical displacement and occasions with extremely strict requirements on the load change rate.
In practical applications, for pipelines and equipment supported by constant force spring hangers, even if displacement occurs, they can obtain a constant supporting force, thus not bringing additional force and stress to the pipelines and equipment, effectively avoiding adverse force transfer in the pipeline system, and strongly ensuring the normal operation of pipelines and equipment.
3. Application Fields of Spring Supports and Hangers
Due to their excellent performance, spring supports and hangers are widely used in many fields.
(1) Power Industry
In power plants, the suspended parts such as boiler bodies, steam, water, smoke, and air ducts, and burners are inseparable from the support of spring supports and hangers. These parts will produce displacement during operation due to factors such as temperature changes and medium flow. Spring supports and hangers can effectively absorb displacement, reduce displacement stress, ensure the safe and stable operation of equipment, and guarantee normal power production.
(2) Petroleum and Chemical Industry
Petroleum and chemical equipment and pipelines usually need to withstand harsh working conditions such as high temperature, high pressure, and strong corrosion. Spring supports and hangers can not only provide stable support for pipelines and equipment but also adapt to complex working conditions, preventing problems such as pipeline leakage and equipment damage caused by displacement, and playing a key role in ensuring the continuity and safety of petroleum and chemical production.
In addition to the power and petroleum and chemical industries, spring supports and hangers are also widely used in metallurgy, textiles, construction, water treatment, shipbuilding, and other industries. In the construction field, they can be used to support pipeline systems such as air conditioning and ventilation; in the water treatment industry, they can provide reliable support for pipelines transporting various liquids; in the shipbuilding industry, they can be used for the installation and fixation of pipeline systems inside ships.
4. Installation and Maintenance of Spring Supports and Hangers
(1) Installation Points
When installing spring supports and hangers, it is necessary to strictly follow the installation load provided by the manufacturer, use upper and lower positioning blocks to fix the indicator plate of the spring support and hanger at the position corresponding to the installation load, so that the spring support and hanger are temporarily in a rigid state. This can ensure that during the installation of the pipeline system, the spring supports and hangers will not displace or deform due to external forces.
The upper and lower positioning blocks can only be removed after the pipeline has undergone cleaning and hydrostatic testing, so that the pipeline can be put into normal use. At this time, the spring supports and hangers begin to play their elastic supporting role and can adapt to the displacement changes of the pipeline during operation.
When the pipeline starts to operate, it is necessary to carefully check whether there is jamming during the displacement of the indicator plate from the installation load to the working load. If jamming is found, the cause should be investigated and handled in a timely manner to ensure the normal operation of the spring supports and hangers.
After the pipeline is put into normal operation, it is necessary to regularly check whether the displacement of the spring supports and hangers under the working load is consistent with the design. At the same time, after the pipeline stops operating, check whether the indicator plate returns to the position of the installation load, as well as the tightness of the spring hangers, etc., to ensure that the spring supports and hangers are always in good working condition.
(2) Maintenance Notes
Regularly inspect the appearance of spring supports and hangers, check whether the springs have cracks, deformation, corrosion, and other abnormalities, and whether the connecting components are loose. If problems are found, they should be repaired or replaced in a timely manner to avoid the failure of spring supports and hangers due to component damage.
Pay attention to the working environment of spring supports and hangers, such as temperature, humidity, corrosive media, etc. For spring supports and hangers working in harsh environments, corresponding protective measures should be taken, such as selecting spring supports and hangers made of corrosion-resistant materials or performing anti-corrosion treatment on them to extend their service life.
When the operating conditions of the pipeline system change, such as changes in temperature, pressure, medium flow, and other parameters, it is necessary to re-evaluate the applicability of spring supports and hangers. If necessary, adjust or replace the spring supports and hangers to ensure that they can continue to provide reliable support for the pipeline system.
As an indispensable important component in industrial pipeline systems, spring supports and hangers, with their unique working principles, diverse types, and wide application fields, play a vital role in ensuring the safe and stable operation of pipeline systems. In practical applications, only by correctly selecting, installing, and maintaining spring supports and hangers can their performance advantages be fully exerted, ensuring the smooth progress of industrial production. With the continuous development of industrial technology, the technology of spring supports and hangers is also constantly innovating and improving, and it will surely show greater value in more fields in the future.
