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Allegheny Valve & Coupling · Hardware & Fasteners
20521
In stock · ships from Knoxville
A 4-inch blind flange with 8 bolt holes, used to seal off a flanged pipe opening or unused connection on tank truck and trailer piping systems.
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Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Commonly used on petroleum trailers. Available in both steel and 304 stainless steel versions; verify material and outer diameter (7.12" for steel, 7.25" for stainless) before ordering.
Part data verified against 4 catalog sources
Numbers this part supersedes or interchanges with. Showing 2 of 2.
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It bolts to a mating TTMA flange, preventing product flow and protecting the line from contamination. Typically replaced when the flange face is corroded, warped, or the gasket surface is damaged, to maintain a leak‑free seal.
Part Number: 20521
BLIND FLANGE 4 8 HOLE
Unit: ea
Dealer: Post Onsite
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