Malleable Iron 321 Flange BS4504 with 4 Bolt Holes NPT Thread

Size: 1/2”-6”
Material: ANSI/ASTM A197-A,KTH350-10
Dimension: ANSI/ASTM B16.3/14/39
Thread: ANSI/ASTM B1.20.1,NPT
Pressure Rating: 363PSI,CLASS150
Surface Treatment:Hot-dip Galvanized,Electro Galvanized,Black
Zinc Coating: ASTM A 153
Certificate: UL Listed / FM Approved / NSF 61
Application: Fire Protection,Waterworks,HVAC,Plumbing,GAS,Irrigation,or other piping systems

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Product Description

Products Details

Malleable Iron 321 Flange BS4504 with 4 bolt holes. Flange BS4504 with 4 bolt holes is a kind of threaded flange. It can be with BSPT or NPT, working pressure is 2.5 Mpa or 363 PSI. Threaded flange is a common flange connection method used to connect pipes and equipment with threaded ports. It consists of two threaded flanges and some bolts and nuts.

Product Drawing

Size A(mm) B(mm) C(mm) D(mm) PCS/CTN.
1/2″ 15 5 67 94.5 120
3/4″ 26 5 73 99.5 100
1″ 19 6 83 114.3 80
1-1/4″ 21 6 87 119.2 50
1-1/2″ 21 7 98 134 38
2″ 26 8 115 150 24
2-1/2″ 30 9 127 164 10
3″ 33 10 146 184 8
4″ 39 11 178 214 6
6″ 40 13 235 279 4

The difference between threaded flang and welded fange:

1. Structure: Welding flange connects pipes or pipe fittings together through welding process, while threaded flange connects threaded pipes through the threads in the inner hole.
2. Usage scenarios: Welded flanges are mainly used in low-pressure situations, such as water treatment systems, petrochemical equipment, shipbuilding and other fields. Threaded flanges are suitable for high-pressure applications, such as aerospace equipment, petrochemical industry and other fields.
3. Connection method: Welding flange uses welding as the connection method, and professional tools and skills are required for installation and disassembly. The threaded flange is connected through threads, making installation and disassembly quick and easy.

How to use the malleable iron flange with 4 bolt holes

The threaded flange connection method is to butt two threaded flanges and tightly connect them together through bolts and nuts through the 4 bolt holes. The threaded flange has internal threads and can be connected to externally threaded pipes or equipment. The connection method of threaded flange is relatively simple and does not require additional sealing gaskets, but its sealing performance is poor and leakage is prone to occur.