Duplex Steel Spectable flanges get their name because they look like a pair of reading glasses, or spectacles. Spectacle flanges, also known as spectacle blind flanges, are most commonly used on piping systems that need to be separated regularly or where the flow through the systems is regularly stopped. One end of the spectacle flange is solid, while the other end has a hole in the center. The spectacle flange can be rotated to place either the solid or hollow end within the pipe system, thereby opening or closing the flow.
For pipe Flanges-regularly seperated for isolation, maintenance or reasons, a spectacle extrudes Solution. Typically, spec blinds was mounted in the open position so-your flow pipe operates and is normally. Blinds is mounted onto one of the $number so is need to isolate a, it ' s easy!
Duplex Steel Spectacle Blinds are used in separating pipe systems for the connection. It is a steel plate divided into two discs of a certain thickness. Out of these two discs, one disc is of a solid plate and other is a ring whose inner diameter is equal to that of a flange. Spectacle Blinds is required in the systems that regularly need to be separated from other installations. Generally, it is mounted in the “Open” position so that flow through the pipe is possible. If it is placed in the “close” position and if it is rotated, then, the pipe is blanked off and no flow is feasible. The whole idea of a spectacle blind is to ensure that an item of equipment is properly and securely blanked off with no leakage or no flow through a valve during maintenance.
The whole idea of a spectacle blind is so that one can be absolutely sure that an item of equipment is properly and securely blanked off with no possibility of any flow or leakage through a valve during maintenance. The flow can be diverted to other items of equipment but not just bypassed around the blank as this would compromise the safety function of the spectacle blind. The flow has to valved off and pressure relieved prior to loosening flange bolts and swinging the blind.
Grade: 2205 (1.4507)
|Tensile strength||620MPa min||Density||7,805kg/m3|
|Yield strength||450MPa mi||Elastic modulus||200GPa|
Stainless Steel :
Grade: 304 (1.4301), 304L (1.4307), 304H (1.4948), 309 (1.4828), 309S, 310, 310S (1.4845) , 316 ( 1.4401), 316H, 316L( 1.4404 /1.4432) , 317, 317L (1.4438), 321 (1.4541), 321 H(1.4878), 347 (1.4550), 347H (1.4961), 904L (1.4539)
Grade: Nickel 200, Nickel 201
Super Duplex Steel:
Grade: 2507 (UNS S32750) (1.4410) (UNS S32750), Z100
Grade: Inconel 600 (2.4640), Inconel 601 (2.4851), Inconel 625 (2.4856), Inconel 718(2.4668)
Grade: Gr.1 (3.7025) , Gr.2 (3.7035) , Gr.3:(3.7055) , Gr.5(3.7164/65), Gr. 7(3.7235) , Gr. 11 (3.7225)
Grade: Monel 400 ( 2.4360), Monel K500, Monel R-405
Grade: Hastalloy B2, Hastalloy B3, Hastalloy C22, Hastalloy C276, Hastalloy X
Grade: Incoloy 800 (2.4958), Incoloy 800H, Incoloy 800HT
The manufacturing process of flange mainly is divided into forging, casting, cutting and rolling. .
The casting and forging flanges have advantages that the blanks of them have accurate shape, size and low costs and only need simple process. But forging flanges have manufacturing defects such as blowholes, cracks, etc and have not very smooth internal organization streamline. The obvious advantages of forging flanges are that they can be forged in various shapes and they have low costs. .
Forging flanges generally have lower carbon content than the casting flanges and are not easy to rust. They have smooth streamline, uniform internal organization, and better mechanical performance than that of casting flanges. There are no defects, such as blowholes and cracks existing in the casting flanges. Forging flanges are able to withstand higher shear and drawing forces than casting flanges. However, if adopting improper forging process, it will also cause appearance of large, uneven grains and solidification cracking phenomenon, resulting in higher cost than the casting flanges. .
We can distinguish between the casting flanges and forging flanges from the different production process. To take the centrifugal flange as an example, it is a kind of casting flange. Centrifugal flanges are produced by a precision casting method, which makes the flanges’ organization smaller than those commonly produced by sand casting and improves the quality of flanges, making fewer occurrences of loose tissue, pore, sand hole etc.
Cutting process refers to producing flanges by directly cutting a round plate with the inner diameter, outer diameter and thickness which can be further processed later from the middle plate, and then processing the bolt hole and waterline. The maximum diameter of such flanges is limited by the width of the middle plate.
Cutting process refers to producing flanges by cutting stripes from the middle plate and then rolling them into round shape. This process is mainly used for the production of large flange. After the rolling process, weld and then flatten the round shape, and finally process the serrated spiral finish and bolt hole.