Blind Flange
It is a flange without any bore in the middle in order to block off media through a pipeline, like what welded cap and casing cap function, except that only casing cap and blind flange are able to be uninstalled at any time.
Blind Flange with Anti-Corrosion Lining
It is a kind of blind flange whose side which is close to media is welded with stainless steel and is used as a blind plate that blocks off corrosive media.
Lap Joint Flange with Welding Neck Collar
It is a movable flange assorted with fitting for water supply and drainage.
Function:
The main purpose of using lap joint flange with welding neck collar is saving materials, which is by making flange plate with low-grade materials and the tube part using the same materials with pipeline.
Advantages:
1. Saving cost
2. Being able to connect with pipes that are inconvenient to weld, such as plastic pipes, RPM pipes
3. Easy installation
Disadvantages:
1. It can only withstand low pressure
2. Low intensity (especially when thickness is less than 3mm)
Lap Joint Flange with Welding-on Collar
It is also a movable flange plate that is directly connected with pipeline, and screws used in the device. The structure of lap joint flange with welding-on collar can be divided into two parts: pipe, which connects with pipeline on one of its end side and the other end side is designed as a cuff; along with flange plate that is set on the cuff.
Advantages:
1. Being able to connect with pipes such as plastic pipes, RPM pipes
2. Easy construction
3. Saving cost
Disadvantages:
1. Being unable to bear with high pressure
2. Low intensity (especially when thickness is less than 3mm)
Slip-on Flange (US standard)
Slip-on Flange is a spare part that connects pipe and pipe, with bores, and screw bolts can be threaded on it so as to connect two flanges, between which a gasket is used for sealing. After screws are tightened, the gasket will deform and fill the irregular surface due to the ratio of surface sealing pressure has reached to a certain figure, thus the connection will be leakless. Connecting by flanges is a dismountable connection type that can be categorized into vessel flanges and pipe flanges according to which part they are going to connect. Normally, slip-on flanges are applicable to connecting with pipes whose nominal pressure are under 2.5MPa.
The structure of welding slip-on flange and pipe has a relatively high strength, rigidity and reliable sealability, also, it is practical enough to be able to withstand high temperature and pressure, repeated bending as well as temperature fluctuation. Slip-on flanges with 0.25-2.5MPa pressure adopt M&F (male and female) face type.
Welding Neck Flange (US standard)
Welding neck flange (US standard) has two manufacturing methods: forging and casting. The connection is with two flange plates and one gasket between them, which are tightened by screws through the bores on the flange.