Key Precautions for Installing Swivel Joints of Loading Arms
Improper installation of loading arm swivel joints often leads to issues such as medium leakage, rotational jamming, and accelerated wear of components. To ensure the long-term stable and safe operation of the loading arm system, the following key requirements must be strictly followed during installation:
1. Pre-Installation Cleaning and Preparation
Before installing the swivel joint, thorough cleaning of the joint itself and the connecting ports of the loading arm is a critical prerequisite to avoid premature failure of internal components.
Component Cleaning: Disassemble the swivel joint (in accordance with the manufacturer's manual) to clean the inner cavity of the shell, the surface of the rotating shaft, and the sealing groove. Use a lint-free cloth dipped in a neutral cleaning agent (e.g., industrial alcohol for non-food-grade scenarios, food-grade cleaning agents compliant with FDA standards for food/beverage applications) to wipe away impurities such as welding slag, metal shavings, and dust. Avoid using abrasive tools (e.g., steel wool) that may scratch the sealing surface or the rotating shaft.
Port Inspection: Check the inner wall of the loading arm's connecting port for burrs, corrosion, or deformation. If burrs are present, use a deburring tool to smooth the port edge-sharp burrs can cut the sealing ring during installation, causing hidden leakage risks.
Drying Treatment: After cleaning, dry all components with compressed air (oil-free and water-free) or let them air-dry naturally. Ensure no residual cleaning agent or moisture remains, as this could react with the medium (e.g., causing corrosion in oil-based media or bacterial growth in food-grade media) or affect the adhesion of lubricating grease.
2. Coaxiality Adjustment
Coaxiality between the swivel joint and the loading arm boom is directly related to the stress state of the rotating shaft and the service life of the sealing elements. Even a small coaxiality deviation can cause uneven force on the rotating shaft during operation, leading to abnormal wear of the seal and rotational jamming.
Measurement Tools: Use a laser alignment tool (preferred for high precision) or a dial indicator to measure the coaxiality of the swivel joint and the loading arm boom.
Adjustment Methods: If deviation is detected, adjust the installation position of the swivel joint or the loading arm boom using shims (stainless steel shims for corrosion resistance) or adjustable brackets. Avoid forcing the joint into alignment by tightening bolts, as this will cause permanent deformation of the shell or the boom.
Dynamic Verification: After initial adjustment, manually rotate the swivel joint 360° to check for uneven resistance. If resistance varies significantly at different angles, re-measure and adjust the coaxiality until the rotation is smooth.
