Double-Acting Compression Joint for Compact HVDC Cable Splicing

The invention uses a nested structure where an inner compression sleeve is placed inside an outer compression sleeve. The inner sleeve compresses the conductor strands first, then the outer sleeve provides additional compression. This nested arrangement allows the joint to maintain a compact cross-sectional diameter comparable to the original cables while achieving sufficient compression force for strong electrical and mechanical connection.

The invention transitions from single-direction compression to multi-directional compression by using both inner and outer sleeves that can apply compressive forces from different directions. The inner sleeve provides radial compression, while the outer sleeve adds circumferential compression, creating a three-dimensional compression field that reduces the joint diameter while maintaining connection strength.

The nested dual-sleeve structure enables progressive compression where the inner sleeve first compresses the conductor strands to a reduced diameter, then the outer sleeve applies additional compression force. This multi-stage compression process ensures that the conductor strands are tightly bound with sufficient compressive stress to withstand tensile forces equal to or greater than the original cables, while maintaining a compact joint diameter.

The invention combines the functions of multiple compression elements (inner sleeve and outer sleeve) into a single integrated joint structure. By merging these compression functions, the joint achieves both compact dimensions and high tensile strength simultaneously, as the combined compressive action of both sleeves creates a mechanically robust connection that matches the original cable properties.

The joint is segmented into distinct functional components: an inner compression sleeve, an outer compression sleeve, and optional positioning elements. This segmentation allows each component to be prepared and positioned independently before final assembly, simplifying the installation process. The modular structure enables workers to insert conductors into the inner sleeve first, then add the outer sleeve, making the process more systematic and less cumbersome than conventional single-piece joints.

The inner compression sleeve can be pre-positioned on the conductor strands before the outer sleeve is added. This preliminary action allows for proper alignment and initial compression to be established before the final assembly step, reducing installation time and complexity. The pre-positioned inner sleeve serves as a guide and initial compression element, making the subsequent addition of the outer sleeve a simpler operation.