We Need to Pay Attention to Several Problems for Purchasing Pipe Fittings
Posted: 05/08/2017 03:52:06 Hits: 51
Several Problems for Purchasing Pipe Fittings
1. Material Problem
Many companies use nonstandard materials, which refers to the amount of nickel. We can use solution to differentiate, but it is clear that this is a misunderstanding. Because the small burden only contains about 7% of nickel, which is undistinguishable. The price difference of the raw material is great, which makes counterfeit materials often occur in the manufacturing, especially in 321 and 316 high nickels.
2. Size Problem
Many customers basically have no technical support for testing. For example, the regular radius of 90 degree elbow is 1.5D, but the molds are usually with the radius of 1.25D in the market. Don't underestimate this 1.25D, for the material weight of the 1.5D 90 degree elbow is very different from that of 1.25D 90 degree elbow. This is the so-called factory standard, which is much lower than the normal standard.
3. Thickness Problem
Of course, nowadays, customers are very smart. They will use calipers to measure the thickness of the pipe fitting. Sometimes customers feel that the thickness has basically achieved the standard after checking, but they neglect one thing, that is, the thickness of the back arc is not enough! Because the thickness of the elbow will be reduced in the pushing process, the diameter can basically meet the standard, while the back arc can not. Usually, experts of this field will use pipes with 114X4 thickness when they need to manufacture elbows with 114X3.5 thickness. If the manufacturer purchases materials with thinner thickness, the natural loss will reduce a lot. But the pipe fitting will appear better than it is, not completely meeting the standard.
4. Solution Treatment and Nondestructive Testing, Sand Treatment and Sandblasting Treatment
Many manufacturers don't provide have solution treatment and 100% penetration of nondestructive testing. Some of them even adopt sandblasting treatment instead of sand treatment, which greatly reduced costs without these processes.
5. Welding without Seams
Welding without seams refers to welded elbows without any signs of welding after grinding, pickling and then sandblasting. You can't know it is the welding elbow, even if you use advanced inspection equipment to check.
6. Spot Welding and Repair Welding
The thickness of the elbow will be reduced in the pushing process, so the manufacturer will choose the thicker pipe. If the manufacturer use thin raw materials, the finished products will not be qualified. Generally the thickness of the pipe fitting will be reduced by 0.4 millimeter. And the thickness will be much lower than that of normal standard due to poor technology or the use of drawing pipes. We can use welding wires with the same material to spot weld the parts where the pipe fittings are not thick enough. Planishing and sandblasting the surface after the parts being welded to a certain thickness. Repair welding can be used for the part with cracks. Even for steel pipes with large seams, they can be repaired by these methods.
1. Material Problem
Many companies use nonstandard materials, which refers to the amount of nickel. We can use solution to differentiate, but it is clear that this is a misunderstanding. Because the small burden only contains about 7% of nickel, which is undistinguishable. The price difference of the raw material is great, which makes counterfeit materials often occur in the manufacturing, especially in 321 and 316 high nickels.
2. Size Problem
Many customers basically have no technical support for testing. For example, the regular radius of 90 degree elbow is 1.5D, but the molds are usually with the radius of 1.25D in the market. Don't underestimate this 1.25D, for the material weight of the 1.5D 90 degree elbow is very different from that of 1.25D 90 degree elbow. This is the so-called factory standard, which is much lower than the normal standard.
3. Thickness Problem
Of course, nowadays, customers are very smart. They will use calipers to measure the thickness of the pipe fitting. Sometimes customers feel that the thickness has basically achieved the standard after checking, but they neglect one thing, that is, the thickness of the back arc is not enough! Because the thickness of the elbow will be reduced in the pushing process, the diameter can basically meet the standard, while the back arc can not. Usually, experts of this field will use pipes with 114X4 thickness when they need to manufacture elbows with 114X3.5 thickness. If the manufacturer purchases materials with thinner thickness, the natural loss will reduce a lot. But the pipe fitting will appear better than it is, not completely meeting the standard.
4. Solution Treatment and Nondestructive Testing, Sand Treatment and Sandblasting Treatment
Many manufacturers don't provide have solution treatment and 100% penetration of nondestructive testing. Some of them even adopt sandblasting treatment instead of sand treatment, which greatly reduced costs without these processes.
5. Welding without Seams
Welding without seams refers to welded elbows without any signs of welding after grinding, pickling and then sandblasting. You can't know it is the welding elbow, even if you use advanced inspection equipment to check.
6. Spot Welding and Repair Welding
The thickness of the elbow will be reduced in the pushing process, so the manufacturer will choose the thicker pipe. If the manufacturer use thin raw materials, the finished products will not be qualified. Generally the thickness of the pipe fitting will be reduced by 0.4 millimeter. And the thickness will be much lower than that of normal standard due to poor technology or the use of drawing pipes. We can use welding wires with the same material to spot weld the parts where the pipe fittings are not thick enough. Planishing and sandblasting the surface after the parts being welded to a certain thickness. Repair welding can be used for the part with cracks. Even for steel pipes with large seams, they can be repaired by these methods.
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Landee is a professional industrial pipe fitting manufacturer and be well accepted by customers all over the world, we has been producing Pipe Fitting for a variety of applications since 1985. welcome to access our website: https://www.landeepipefitting.com.
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