The pipe support is a pipe accessory that directly supports the pipe and bears the force of the pipe. Its function is to support the pipeline and limit the displacement of the pipeline. The support bears the gravity of the pipeline and the force caused by the internal pressure and temperature changes of the external load, and transmits these loads to the building structure or the pipeline components on the ground.
一、Movable support
The movable support is a pipeline support that allows relative displacement between the pipeline and the supporting structure. According to its structure and function, the movable support can be divided into sliding, rolling, spring, suspension and guiding support forms.
1. The sliding support and the bracket are composed of a steel pipe support installed on the pipe and a supporting structure below. It bears the vertical load of the pipeline and allows the pipeline to slide in the horizontal direction. According to the shape of the cross-section of the tube bracket, there are curved trough type, T-shaped bracket type and curved plate type. In the first two forms, the pipeline is supported by the support, and the sliding surface is lower than the insulation layer, and the insulation layer will not be damaged. The sliding surface of the curved plate sliding support is directly attached to the pipe wall, so the insulation layer should be removed when the support is installed, but the pipe installation position can be lower.
2. The rolling bearing is composed of a steel pipe holder installed on the pipe and a roller, roller or ball disk installed on the supporting structure. With roller type and roller type bearings, when the pipe is displaced in the axial direction, there is rolling friction between the pipe support and the rolling parts, and the friction coefficient is below 0.1; but when the pipe is displaced in the lateral direction, it is still sliding friction. With ball-bearing disc support, the horizontal movement of the pipe in all directions is rolling friction. Rolling bearings require necessary maintenance to keep rolling parts in normal condition and are generally only used for overhead laying of pipelines.
3. Suspension brackets are often used on indoor heating pipes. The pipes are suspended under the bearing structure with hoop, boom and other rods. The structure of the suspension bracket is simple, and the pipe expansion resistance is small; when the pipeline is displaced, the boom shakes, because the swing range of each bracket boom is different, it is difficult to ensure that the pipeline axis is a straight line. Therefore, the pipeline thermal compensation needs to be free from the influence of the bending deformation of the pipeline. Compensator.
4. The structure of the spring support is generally constituted by adding a spring under the tube support of the sliding support, the rolling support or the component of the suspension support. Its characteristic is to allow the horizontal displacement of the pipeline and adapt to the vertical displacement of the pipeline, so that the vertical load of the pipeline on the support does not change much. It is often used where the pipeline has a large vertical displacement to prevent the pipeline from separating from the support, causing excessive stress on the adjacent support and the corresponding pipe section.
5. The guide support is a support form that only allows the pipeline to expand and contract in the axial direction and restricts the lateral displacement of the pipeline. The structure is usually to provide guide baffles on both sides of the pipe support of the sliding support or rolling support along the axial direction of the pipeline. The main function of the guide support is to prevent longitudinal instability of the pipeline and to ensure the normal operation of the compensator.
二、Fixed Bearing
The fixed support is a pipeline support that does not allow relative displacement between the pipeline and the supporting structure. It is mainly used to divide the pipeline into a number of compensation pipe sections and perform thermal compensation separately to ensure the normal operation of the compensator.
The most commonly used is the fixed support of metal structure, there are snap ring type, welded angle steel fixed support, curved groove fixed support and baffle type fixed support, etc. The first three types of bearing axial thrust are relatively small, usually no more than 50kN. When the axial thrust bearing the fixed bearing exceeds 50kN, the baffle-type fixed bearing is often used. In non-ditch laying or impassable trenches, fixed supports are also made into reinforced concrete fixed piers.
