Flanges are disc-shaped parts that are most common in plumbing and flanges are used in pairs. In plumbing, flanges are mainly used for the connection of steel pipes. In the pipelines that need to be connected, a variety of flanges are installed, and the low-pressure pipelines can use wire-bonded flanges, and the welding flanges are used at pressures above 4 kg. A sealing point is added between the two flanges and then fastened with bolts. Different pressure flanges have different thicknesses and use different bolts.
Pumps and valves, when connected to the pipeline, part of these equipment, also made into the corresponding flange shape, also known as flange connection. Connection parts that are closed at the same time by bolting on both planes are generally referred to as “flanges”. For example, the connection of ventilation ducts may be referred to as “flange parts”.However, this connection is only a part of the equipment, such as the connection between the flange and the water pump, it is not good to call the pump “flange parts”. Smaller such as valves, etc., can be called “flange parts”.
Flange flange connections are an important connection for pipeline construction.
Flange connection is to fix two pipes, pipe fittings or equipment on a flange, and between the two flanges, with flange mats, bolted together to complete the connection. Some fittings and equipment have their own flanges and are also flanged.
Flange threaded connection (wire connection) flange and welded flange. Low-pressure small-diameter wire-bonded flanges, high-pressure and low-pressure large diameters are all welded flanges. The thickness of the flanges of different pressures and the diameter and number of connecting bolts are different.
Depending on the level of pressure, the flange pads are also available in different materials, from low pressure asbestos pads, high pressure asbestos pads to metal pads.
Flange connections are widely used in industrial piping. In the home, the pipe diameter is small and low pressure, and the flange connection is not visible. If you are in a boiler room or production site, there are flanged pipes and equipment everywhere.
Pipe connection, heat treatment and non-destructive testing pipe section connection pipe can be directly connected in the following ways: (1) Butt welding between pipes or between pipe and valve box or other accessories, butt welding should be full penetration type, and the root quality is Special regulations, or full penetration type, but no special provisions for root quality; (2) Sleeve welded joints, sleeve welding shall be carried out according to recognized standards, with appropriate size sleeves and related welding processes; (3) Approved type Threaded sleeve connection. The scope of use of the above pipe connection method is as follows: (1) Butt weld connection and sleeve weld connection shall comply with the requirements of Table 22.214.171.124(1). The connection mode between the pump and the pipe system is applicable to the pipe system. The outer diameter is taken to improve the quality of the weld root. The butt welding I, II, III does not adopt the butt welding of the root quality of the weld. II, III However, toxic media or pipes that are expected to cause fatigue and severe corrosion
during work are excluded D ≤ 88.9 mm
Threaded sleeve connections shall be in accordance with recognized standards. Threaded sleeve connections can be used for piping systems of the following outer diameters, but not for piping systems that carry toxic or flammable media or that are expected to cause fatigue and severe corrosion during operation. Threaded connections in the carbon dioxide system are only available in the protected space and in the carbon dioxide cylinder chamber. 1 Threaded connection of tapered thread can be applied to Class I pipe system with outer diameter of not more than 33.7mm and class II pipe system with outer diameter of not more than 60.3mm. Threaded connection of 2 parallel thread can be used for III with outer diameter of not more than 60.3mm Grade piping, 3 In special cases, if it meets the requirements of recognized international or national standards, it can accept dimensions larger than the above. Flange Connections Typical flange connections are indicated for small diameter pipes. Depending on the individual case and operating conditions, sleeve connections, threaded sleeve connections or other pipe sections can be used for direct butt joints (eg horn sleeve or shoulder joint). The provisions for the selection of the above various flange connections. Typical flanged applications are toxic or corrosive media. The size of the flammable flange and its bolts should be selected according to national standards or acceptable standards.
The dimensions of the flanges and their bolts for special purposes should be considered separately. Mechanical joints of all types of mechanical joints to which this section applies. . Mechanical joints shall be type approved according to the requirements of Appendix 3 of this Chapter for different purposes and locations. The mechanical joint shall be constructed to prevent seal failure due to pressure pulsation, piping vibration, temperature changes and other similar adverse effects after shipment. Pumps and Pipes Steel Seagoing Rules for Classification Typical flanged mechanical joints are to be compatible with piping materials and internal and external media. Mechanical joints should be able to withstand internal and external pressure. The mechanical joints used for the suction line should be able to work properly under a certain degree of vacuum. The reduction in wall thickness due to the use of snap rings or other structural elements should be considered when determining the minimum wall thickness at design pressure. Pumps and Pipes Steel Seagoing Classifications Mechanical joints that cause fire or water immersion in the event of damage and should not be directly connected to the pipe section of the sea or flammable liquid tank. The number of mechanical joints in the oil circuit system should be as small as possible.