What is Threaded Flange?
The threaded flange means that the inner hole of the flange is a thread, and the shape is like the slip-on flange. It could be plate shaped or with a hub for the longer threads. The threaded flange is usually supplied with a flat face (FF) or raised face (RF) sealing face.
Compared with the weld neck flanges and slip-on flanges, the threaded flanges has the advantages of convenient installation and maintenance, and it can be used in some piping systems that are not allowed to be welded on site. However, because threaded flange does not have welding work, it is more prone to leakage than welded connections. It is recommended not to use the threaded flange to avoid leakage when the pipe temperature changes sharply or the temperature is higher than 260 ° C and lower than -45 ° C.
Threaded flanges are available in various materials, including carbon steel, stainless steel, alloy steel and others. The choice of material depends on factors, such as pressure, temperature, and the nature of the fluid or gas being transported.
Applications
Threaded flanges are widely used for the pipeline connections of petroleum & gas, petrochemical, water engineering, ship building, seawater cleaning, construction etc.
Technical Specifications
Threaded flange has many sizes no matter for carbon steel or stainless steel. The following information is just about their sizes and tolerances.
Threaded Flange type According to sealing face
Threaded Flanges Type According to standards
ASME B16.5 Threaded Flange
ASME B16.5 standard is the most popular standard in the world for producing flanges. ASME B16.5 threaded flange is available in sizes from NPS 1/2 to 24 inches for the pressure ratings of Class 150 to Class 900; The pressure ratings for Class 1500 and Class 2500 are available in sizes from NPS 1/2 to 2-1/2 inches.
EN1092-1 Threaded Flange
EN1092-1 standard is commonly used in European countries. EN1092-1 threaded flange is usually made to the specific standards of EN1092-1 type 13A/B PN6, PN10, PN16, PN25, PN40, PN63 and PN100, with the nominal sizes ranging from DN10 to DN2000. Threaded Flanges are mostly used in low pressure, yet smaller diameter applications.
JIS B2220 Threaded Flange
For metric sizes, Japan Industrial Standard (JIS) is yet another option. The inner diameter of the JIS B2220 flange is manufactured slightly larger than the outside diameter of pipes. JIS B2220 threaded flange provides in JIS 5K, JIS 10K, JIS 15K, and JIS 20K pressure classes, sizes range from 10A to 1500A.
Threaded Flange material
Quality Assurance
1) Raw material re-inspection: Raw materials undergo chemical composition analysis, mechanical property testing and non-destructive testing.
2) After cutting the material, inspect the cut surface and detect the weight.
3) Non-destructive testing: ultrasonic flaw detection, magnetic flaw detection, radiographic flaw detection, specification and size inspection, surface defect detection, etc.;
4) Paint marking: Carry out steel stamping or electric corrosion marking on the flange, including: type, pressure, specification, material, standard, etc.