Bk 521-204BG Malleable Black Iron Coupling 3/4 in

Product Description

The BK 521-204BG is a 3/4-inch malleable black iron coupling designed for threaded pipe assemblies in gas, water, and general-purpose piping systems. Manufactured from malleable iron meeting ANSI/ASTM A-197 material standards, this coupling joins two sections of male-threaded pipe in a straight run. Threads conform to ANSI B1.20.1, and dimensional standards meet ANSI/ASME B16.3, B16.14, and B16.39. Each fitting is individually flag tagged and 100% inspected and quality tested before shipment. Licensed plumbers and pipefitters install this fitting in both residential and light commercial applications.

This coupling is suited for use in black iron pipe systems where a threaded, non-union straight connection is required. Common applications include gas distribution lines, steam piping, compressed air, and general fluid conveyance. The 3/4-inch size is a standard trade size found throughout residential gas supply runs and commercial mechanical rooms. Plumbing and mechanical contractors working with Schedule 40 black iron pipe will encounter this size routinely in branch and main line assemblies.

Key Features

• Malleable iron construction per ANSI/ASTM A-197 for durability in threaded piping systems
• Threads cut to ANSI B1.20.1 for reliable engagement with standard NPT pipe
• Dimensional compliance with ANSI/ASME B16.3, B16.14, and B16.39
• 100% inspected and quality tested at the factory
• Individually flag tagged for identification and traceability
• Sold individually; minimum order quantity of 5 units

Compatibility

Designed as an OEM-style replacement and standard-use fitting for 3/4-inch NPT threaded black iron pipe systems in residential and commercial gas, steam, and fluid piping applications.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable local codes, the International Fuel Gas Code (IFGC), and the International Plumbing Code (IPC). Shut off gas or fluid supply and depressurize the line completely before disassembly or fitting installation. Apply an approved thread sealant or pipe tape rated for the intended service to the male threads before assembly. Do not overtighten; follow standard hand-tight-plus-turns practice appropriate for malleable iron fittings.

Technical Specifications

• Material: Malleable Black Iron, ANSI/ASTM A-197
• Thread Standard: ANSI B1.20.1 (NPT)
• Dimensional Standard: ANSI/ASME B16.3, B16.14, B16.39
• Pipe Size: 3/4 inch
• Weight: 0.295 pounds
• Unit of Measure: Each
• Minimum Order Quantity: 5
• UPC: 00032888406902

Standard Information

• Brand: BK
• Manufacturer Part Number: 521-204BG