Types of Stainless Steel Flanges Explained
November 02, 2011 in Blog, Manufacturing, News & Articles, Pipes Valves and Fittings, Valves and Fittings by Tim Walshauser
High pressure steel flanges are essential to include in your next piping project. Stainless steel flanges are highly resistant to corrosion and contain enough strength for your industrial piping plan. For high temperature and pressure treatment, consider purchasing high pressure steel flanges that comply with ASTM, ASME, ANSI and/or API standards.
API vs. ASME/ANSI standards:
Flanges meeting API standards can withstand high pressures and temperatures. The main difference between flanges that meet API standards and those that meet ASME or ANSI standards is the material used that can handle a high-pressure environment. Typically they are more efficiently used in dealings with gas and oils. When working with water, air, and steam in an industrial setting, ASME/ANSI flanges are more common.
Types of stainless steel flanges:
- Weldneck flanges create a smooth weld matching the thickness and bevel of the pipe. With a diameter that matches the inside of the pipe, they work by transferring pressure from the flange to the pipe. Typically used for high-pressure applications, weldneck flanges are the most commonly used flange style.
- Threaded Pipe flanges are unique and beneficial because there is no need to weld them to the pipe. Instead, they have an outer thread. These are most commonly used for small diameter projects with high pressure.
- Slip-On flangesare the least expensive type and come in large or small sizes. They have a diameter slightly larger than the pipe, allowing them to easily slip directly over the pipe. After slipping on , they are then also fillet welded. The two types of slip-on flanges are the ring and hub flanges, differing by size specifications.
- Lap Joint flanges are typically used in conjunction with either a stub end or taft. Because it is easily assembled and aligned, this type of flange should be used in low-pressure applications or those that require frequent reassembling.
- Blind flanges, also known as blanking flanges, are used to seal off pipelines, pumps or valves to prevent flow. They are suitable for testing the pressure of liquid or gas flowing through a pipe and can sometimes be sued as an inspection cover. It is easily manageable and can be reversed to allow for expansion.
- Socket Weld flanges are used in high pressure, smaller pipe applications. Here, the pipe is inserted into the socket and fillet welded at the top allowing for a smoother fluid and gas flow through the pipe.
- Ring-Type Joint flanges can help in high-pressure applications to prevent leaks. These flanges have a unique groove that can be compressed onto a Slip-On, Blind or Weldneck flange. This will further allow the pipe to withstand extreme pressure and temperature.
St Louis Pipe and Supply offers high pressure steel flanges including weldneck flanges and slip-on flanges. All stainless steel flanges meet or exceed ASTM, ASME, ANSI and/or API standards.