What is a rolled flange?
The rolled flange is cut into slats by the middle plate, and then rolled into a round welded joint and then processed by a flattening process. The coil is made up of cold and hot coils. After processing into a circle, the water line, bolt holes, and stops are processed. This is generally a large flange, which can be up to 7 meters in one shot. Most of the plate type flat welding flanges are connected by welding. If the production process is produced in stages, it can be made to specifications of 12 meters to 15 meters or more. This type of flange has a good quality guarantee. Because the raw material is medium plate, the density is good. The welding process at the interface of the rolled flange is a top priority, and X-ray or ultrasonic film inspection is required. The interface is done, and the material of the entire flange is no problem. Relatively speaking, the product is thinner, lighter in weight, narrower in one side of the product, and has a higher sealing price, and some of the thicker, heavier, and less cumbersome processing flanges are available. It is lower.
When the bolt hole is machined, it is not allowed to hit the bolt hole to the place where the weld is made. Such flanges are made of carbon steel, stainless steel, alloy steel, etc. Lpipe.com is capable of producing products up to 7 meters. Rolling flanges of more than 3 meters must first consider the transportation problem when signing the contract. Because the height limit of the overpass on the highway is 4.5 meters. The height of the car’s trunk is about 1.5 meters, and the height of the flange is too high. Ultra-high and ultra-wide coiled flanges can be applied to the local traffic management department for bulk transportation. However, the transportation cost of large parts is too high, it is recommended to produce in sections and go to the site for installation.
Algorithm for theoretical weight of carbon steel coiled flanges:
1. First use (outer diameter – inner diameter) divided by 2 to get the result.
2. Reuse (outer diameter – above result) multiplied by the above result X0.0246615X thickness
3. After the above two steps, the theoretical weight of the carbon steel coiled flange is obtained.
For example, the calculation method of the rolled flange with an outer diameter of 3000 mm, an inner diameter of 2800 mm and a thickness of 70 mm is as follows:
After calculation, the theoretical weight of the flange is 500.63kg.
In the machinery industry, many manufacturers use flanges (also known as reinforcement rings) only as a connection or support, so steel strips (flat steel) can be directly rolled onto the flanged equipment directly into the required ring. The circle can be used, this processing method saves labor and materials, and greatly saves costs.
Classification of rolled flanges:
Cold rolled flange
The cold coil flange is a disc-shaped part that is commonly used in boiler piping engineering. The cold coil flange is mainly used for pipe connection. At the pipe joints to be connected, one roll flange is installed, and the low pressure pipe can use a wire-wound flange. The pressure of 4 kg or more is used to weld the cold-roll flange. A seal is placed between the two cold-roll flanges and then bolted. Cold-rolled flanges of different pressures have different thicknesses and use different bolts. Cold-rolled flanges increase with the percentage of carbon content. They are also called ordinary carbon steels. Nowadays, steels that are common in drunk are relatively low-priced, cold-rolled. Flange quotations provide relevant material properties to the cold-roll flange, what the cold-roll flange means, which is acceptable for many applications. The cold coil flange contains approximately 0.05 – -0.15% carbon, which enhances its toughness and plasticity. The rolled flange has a relatively low tensile strength, non-standard flange, but the rolled flange is relatively cheaper and easier to form. Coiled flanges often use a large amount of steel, and the hardness of the rolled flange can be increased by the carburized surface. The density of the rolled flange is approximately 7.85 grams per cubic centimeter.
Hot coil flange
The hot-roll flange blank is carried out by rolling a steel slab into a flat steel by a hot-rolling machine and rolling it into a circle. It is a relatively advanced flange blank manufacturing form in China, and the traditional flange manufacturing process. Compared to the following, there are obvious advantages:
(1) All raw materials are made of standard billet, and the material is stable and reliable;
(2), the flatness and ovality of the blank can be precisely controlled to minimize the processing volume;
(3) The processing precision of the blank is high and the machining efficiency is increased by 50%;
(4), the finished product rate is high, the material ratio reaches 1.25-1.35;
(5) The newly developed convex flange blank product saves about 24% of raw materials compared with the traditional process;
(6), energy saving and consumption reduction, the new process can produce 60% coal consumption per ton of flange compared with the traditional process, and the power consumption is 40%;
(7), can be adjusted according to customer requirements.
The difference between a cold coil flange and a hot coil flange is:
The cold coil flange is formed at a low temperature (below the recrystallization temperature);
The hot coil flange is formed at a high temperature (above the recrystallization temperature).
Rolling flange processing technology:
The middle plate is first cut into suitable slivers, and the length of the sliver is determined according to the specifications of the large flange. Then, the ring is rolled into a circle, and the joint is welded firmly with the electrode. Then use the press to flatten it, and then use the lathe to process the waterline, chamfering, etc. Finally, the indexing disc is used in conjunction with the drilling machine to process the hole of the bolt hole.
The cost of a rolled flange is lower than that of a forged one. But some oversized flanges are forged. Most of these products are weighed by the theoretical weight. In the calculation, the weight of the water line, the stop, the bolt hole and the chamfer are not reduced. The price of a flat product is lower, but if a large flange with a process such as a dovetail is expensive, the price will be higher. The theoretical weight is calculated according to the above formula.
The rolled flange replaces the original steel plate blanking, docking correction, lathe processing and other complicated processes, and saves oxygen, acetylene, labor, raw materials, etc., and the process is simpler. As a connection and support, the products are widely used. In the wind turbine, bridge last class, chemical equipment, cable racks, centrifuges and other industries.
The rolled flange is a ring or arc that is directly cold-formed into the required diameter. The roundness is determined according to the customer’s requirements. The customer can directly use it on the cylinder or in the cylinder as a connection. Flange, talking about the support ring, etc., is convenient and inexpensive.
The welding process at the interface of the rolled flange is a top priority, and X-ray or ultrasonic film inspection is required. The interface is done, and the material of the entire flange is no problem. Relatively speaking, the product is thinner, lighter in weight, narrower in one side of the product, and has a higher sealing price, and some of the thicker, heavier, and less cumbersome processing flanges are available. It is lower.
Lpipe.com is a professional manufacturer of stainless steel coiled flanges, which produces rolled flanges of various materials such as super duplex stainless steel, duplex stainless steel, alloy steel and stainless steel.
Source: China Stainless Steel Flange Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)