AN IMPROVED LOOSE TUBE CABLE WITH DRY WATER BLOCKING ELEMENTS

摘要

In today’s economy, where cable designs have been developed to accommodate opticalrnfiber in virtually every environment, improvements to existing designs have becomernimperative. These improvements come in the form of increased ease of handling andrnentry, effective cable performance, reductions in cable weights, etc. An improvedrncable design is introduced to address these issues for loose tube applications.rnStandard loose tube optical cables, which comprise a significant share of commerciallyrnavailable designs, currently contain a viscous falling/flooding compound (jelly) tornprovide both axial and radial water penetration resistance. This component of thernconventional design is responsible for a variety of inconveniences. When preparing forrncable connections, the filling/flooding compound must be thoroughly cleaned from therncable components and working area which creates a time consuming, hence costly task.rnAdditionally, there are manufacturing issues regarding adequate application of therncompound to the cable core structure to provide reliable long-term water blockingrnalong the entire cable length.rnA new loose tube cable design that addresses the aforementioned issues is introduced.rnThe proposed cable incorporates water blocking provisions via “dry” components in thernform of water blocking yarns and tapes. These materials can be easily applied duringrnthe core stranding process and/or the cable jacketing process. This design providesrnboth handling and cable performance improvements when compared to the conventionalrnjelly filled cable.rnFor cable manufacturers, the elimination of the jelly means reduced maintenance ofrnprocessing lines, increased line speeds when limited by the core filling/floodingrnprocess, and significantly increased confidence in uniform water penetrationrnperformance of the product. Those who install and connect cables will be handling arnlighter and much more user friendly cable. Time studies of this cable, compared to thernconventional loose tube cable, will illustrate reductions in preparation time of cablernends and mid-span access. This time reduction is realized through the elimination ofrnjelly clean up time combined with significantly easier removal of the strength membersrnand binding materials. Additionally, the lighter weight of this cable makes installationrnof longer lengths by current pulling or blowing techniques feasible.