How do I know what class my flange is?
When trying to determine the flange rating of a pump, the best method is to look for a stamp printed onto the flange. If one is not visible, or it is worn, then start by counting the number of bolt holes. This will point you to a narrower range of flange sizes in the chart below. Next measure the bolt circle diameter.
How do I know what flange I have?
You need to find the outer diameter, the inner diameter, the number of bolt holes, bolt hole diameter, and the bolt circle diameter. Bolt circle diameter (B.C.) is one of the most important measurements to make when identifying a flange.
What is the difference between RF and FF flange?
RF is raised face flange, which can be used under the pressure of PN1. FF is flat face flange, which has lower sealability than RF, its pressure is 1.6~2.0MPA (standard: GB9113), and other joint faces like RTJ, FM have higher pressure. The gaskets for RF and FF can be used for each other.
What is the difference between slip on and weld neck flange?
The Weld Neck Flange is easily recognizable by the hub that gradually tapers from the bolted connection to the pipe. The Slip On Flange is connected to the pipe by two welds, one on the back side of the Flange and one on the inside of the Flange. …
What does RTJ flange mean?
RING TYPE JOINT
How are slip on flanges welded?
Flanges and fittings are either slip-on or weld-neck. Slip-on fittings slip onto the end of the pipe. The flange is then welded around the contact points on the inside and outside of the pipe and the flange. Slip-on flanges are not considered as strong a joint as weld-neck or butt-welded connections.
Can you weld a slip on flange to a 90 degree elbow?
There is no Code restriction against welding a Slip-On (SO) Flange directly to an elbow, a Reducer, a Tee or any other fitting.
Are lap joint flanges raised face?
Lap Joint Flanges have all the same common dimensions as any other flange named on this page however it does not have a raised face, they used in conjunction with a “Lap Joint Stub End”.
Why raised face flange is used?
The raised face is the most common flange face type used. It’s called a raised face because it has a raised surface above the bolting circle where the gasket is placed. The purpose of the RF flange is to focus more pressure on the smaller gasket area, which increases the pressure containment capabilities of the joint.
What is a lap joint flange used for?
The lap-joint flange and stub end assembly are used mainly in piping systems that necessitate frequent dismantling for inspection or routine maintenance. It is also used in the erection of large-diameter or hard-to-adjust piping configurations because of its quick bolt hole alignment.