# US 10,246,253 B2 · Floating roof reel type ground > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,246,253 B2 - Document ID: US10246253B2 - Status: Granted - Kind: B2 - Application number: 15/006,487 - Filed: 2016-01-26 - Published: 2016-08-25 - Granted: 2019-04-02 - Earliest claimed: 2015-02-25 - Applicants: Lightning Eliminators - Inventors: Kirk S. Chynoweth; Lee B. Howard - Web page: https://patentgrep.com/patent/US10246253B2 ## CPC - B65D 90/46: Arrangements for carrying off, or preventing the formation of electrostatic charges (carrying-off, or preventing the formation of electrostatic charges in general H05F) - B65D 88/46: with mechanical means acting on the seal - B65D: CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES ## Abstract In a fluid reservoir tank such as an oil tank, the metal roof floats. The American Petroleum Institute (API) Recommended Practice (RP) number 545 requires a floating roof to tank resistance of less than 30 milli-ohms. The improved cable system uses a preferred aluminum braided cable to provide low resistance combined with resistance to sour fluids. Prior art used copper and tinned copper braided cables. The new reel is factory pre-assembled and tensioned using a new cable guide with a cable stop bar which stops a cable stop attached near the end of the (approximately 80 foot) cable. A new spring assembly increased tension and extends cable life by minimizing slack in the cable. ## Claims ### Claim 1 In a fluid/liquid storage tank with a sidewall and a floating roof floating atop the fluid/liquid, an improved grounding system comprising: a reel connected to the sidewall; said reel having a low impedance conductor for lightning related frequencies connected to the floating roof; said conductor comprising a bare braided aluminum cable; said reel having a take up spool which keeps any slack out of the conductor and maintains a shortest fractional length; said spool having a rewind spring assembly that produces about 80 to about 90 pounds of rewind tension at a maximum payout; said reel having a cable guide with a built in cable stop anchor and a low resistance connection to a spool axle; wherein an excess length of said conductor is wound around said take up spool thereby shorting together adjacent sections of said conductor wound around said take up spool; said conductor having a cable stop; and said reel having a U shaped mounting bracket that bolts to a flat indent on a left end of the spool axle and to a flat indent on a right end of the spool axle. ### Claim 2 (depends on 1) The grounding system of claim 1, wherein the spring assembly further comprises two springs tied in series via a collar. ### Claim 3 (depends on 1) The grounding system of claim 1, wherein the U shaped mounting bracket further comprised a flat flange at each of its ends which fit against the respective flat indent. ### Claim 4 (depends on 1) The grounding system of claim 1, wherein the cable guide has a welded connection to the spool axle. ### Claim 5 (depends on 1) The grounding system of claim 1, wherein the bare braided aluminum cable is about 1⅜″ wide by about 0.120″ thick. ### Claim 6 (depends on 5) The grounding system of claim 5, wherein the bare braided aluminum cable has a double braided connection assembly for bolting to a vertical roof flange between a first and a second braid of the double braided connection assembly. ### Claim 7 (depends on 1) The grounding system of claim 1, wherein the bare braided aluminum cable with the cable stop is pre-tensioned at final assembly with the cable stop tensioned against the cable stop anchor. ### Claim 8 (depends on 1) The grounding system of claim 1, wherein the maximum payout is about 80 feet. ### Claim 9 (depends on 1) The grounding system of claim 1, wherein the spool axle further comprises a handle at each end. ### Claim 10 (depends on 1) The apparatus of claim 1 further comprising a plurality of said reels and low impedance conductors connected to the sidewall. ### Claim 11 In a fluid/liquid storage tank with a sidewall and a floating roof floating atop the fluid/liquid, an improved grounding system comprising: a reel connected to the sidewall; said reel having a low impedance conductor for lightning related frequencies connected to the floating roof; said conductor comprising a bare braided aluminum cable; said reel having a take up spool which keeps any slack out of the conductor and maintains a shortest fractional length; said spool having a rewind spring assembly that produces about 80 to about 90 pounds of rewind tension at a maximum payout; said reel having a cable guide with a built in cable stop anchor and a low resistance connection to a stationary spool axle; wherein an excess length of said conductor is wound around said take up spool thereby shorting together adjacent sections of said conductor wound around said take up spool; said conductor having a cable stop; and said reel having a U shaped mounting bracket that connects to the stationary spool axle. ### Claim 12 (depends on 11) The grounding system of claim 11, wherein the spring assembly further comprises two springs tied in series via a collar. ### Claim 13 (depends on 11) The grounding system of claim 11, wherein the U shaped mounting bracket further comprised a flat flange at each of its ends which fit against a respective flat indent on each end of the stationary spool axle. ### Claim 14 (depends on 11) The grounding system of claim 11, wherein the cable guide has a welded connection to the spool axle. ### Claim 15 (depends on 11) The grounding system of claim 11, wherein the bare braided aluminum cable is about 1⅜″ wide by about 0.120″ thick. ### Claim 16 (depends on 15) The grounding system of claim 15, wherein the bare braided aluminum cable has a double braided connection assembly for bolting to a vertical roof flange between a first and a second braid of the double braided connection assembly. ### Claim 17 (depends on 11) The grounding system of claim 11, wherein the bare braided aluminum cable with the cable stop is pre-tensioned at final assembly with the cable stop tensioned against the cable stop anchor. ### Claim 18 (depends on 11) The grounding system of claim 11, wherein the maximum payout is about 80 feet. ### Claim 19 (depends on 11) The grounding system of claim 11, wherein the spool axle further comprises a handle at each end. ### Claim 20 (depends on 11) The apparatus of claim 11 further comprising a plurality of said reels and low impedance conductors connected to the sidewall.