Rubber expansion joint is a core flexible fitting for the inlet and outlet pipelines of pumps and valves. It can effectively compensate for pipeline displacement and absorb equipment vibration impact. Whether its installation and adaptation are standardized directly affects the operational stability of pumps, valves, and the entire pipeline system. The following shares practical installation and adaptation skills, which balance adaptability and use safety to make the rubber expansion joint exert the best effect.
1. Precise Adaptation and Selection Skills
Select a rubber expansion joint of the same specification according to the nominal diameter and working pressure of the pump and valve inlet and outlet. If the conveying medium is acid-base or high-temperature fluid, it is necessary to match corrosion-resistant and high-temperature-resistant rubber materials, such as fluororubber and EPDM rubber, which are very suitable.
Select the model with the corresponding compensation according to the vibration amplitude of the pump and valve operation, and the axial and radial displacement of the pipeline. Prioritize single-sphere or double-sphere structures to meet the flexible compensation requirements of the pipeline.
The matching flange standard of the rubber expansion joint must be consistent with that of pumps, valves, and pipelines to ensure the tight fit of the connecting surface and avoid seal failure and uneven stress caused by flange specification deviations.
2. Key Points of Standard On-site Installation
Keep the rubber expansion joint coaxial with the inlet and outlet of pumps and valves during installation, and it is strictly forbidden to force eccentric or torsional installation. Otherwise, the rubber body is prone to cracks due to long-term torsion, which greatly shortens the service life.
Install it as close as possible to the inlet and outlet of pumps and valves, and reserve a reasonable installation space to prevent collision with surrounding equipment during pipeline expansion and contraction. Tighten the bolts evenly diagonally with moderate force and do not over-tighten to avoid damaging the sealing surface and affecting the sealing effect.
Install a limiting device if necessary. If the pipeline is under high-pressure working conditions or a long-distance layout, it is necessary to set limiting tie rods on both sides of the rubber expansion joint to prevent the joint from falling off caused by excessive displacement. At the same time, do not make the limiting device too tight to restrict the flexible compensation effect of the rubber expansion joint.
3. Adaptation Protection and Post-use Notes
If the rubber expansion joint is at risk of medium scouring and debris impact during the operation of pumps and valves, install a protective sleeve on the outside to avoid damage to the rubber layer. For outdoor installation, it is also necessary to take good sun protection and anti-aging protective measures.
The rubber expansion joint used in conjunction with pumps and valves should be kept away from the direct vibration area of the equipment, and can also be used with shock absorption pads to improve the overall anti-vibration effect. Regularly inspect the sealing surface and rubber body at ordinary times, and replace them in time if bulges or cracks are found.
Different types of pumps and valves need to be adapted to different installation methods. The inlet and outlet of centrifugal pumps and gate valves are preferably installed horizontally, and vertical pumps and valves can use axial compensation type rubber expansion joints, which fit the stress characteristics of equipment operation and make the use more stable.
