how foundries perform welding of cast iron castings?

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Foundries of CI Castings - BY RAINBOW TECHNOCAST PVT. LTD.

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Engineers may find the job of welding bit tricky, yet they do it all with perfection under harsh environment. In most cases, welding process of cast iron involves casting repairs.

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Page 1: How Foundries Perform Welding Of Cast Iron Castings?

Foundries of CI Castings - BY RAINBOW TECHNOCAST PVT. LTD.

Page 2: How Foundries Perform Welding Of Cast Iron Castings?

Foundries of CI Castings

Inroduction How Foundries Perform Welding Of Cast Iron Castings? Images of Cast Iron Castings Welding Techniques With Preheat Welding Techniques Without Preheat Conslusion Contacts Blogs and Articles

Page 3: How Foundries Perform Welding Of Cast Iron Castings?

Introduction

Engineers may find the job of welding bit tricky, yet they do it all with perfection under harsh environment. In most cases, welding process of cast iron involves casting repairs. These repairs may be done inside the foundry that is producing various cast iron castings, or may be done when engineers determine them after machining process. Defected cast iron components can be repaired with welding technique. Broken cast iron components are rare and fixed by welding process.

Page 4: How Foundries Perform Welding Of Cast Iron Castings?

How Foundries Perform Welding Of Cast Iron Castings?Manufacturers of castings use various range of cast iron and out of them, gray iron is their most preferred material to cast and shape. We are now going to discuss about a fact file of cast iron that helps us in understanding the challenges of welding.

(1) Cast iron usually has 2%-4% carbon content (this is about 10 times more than steel). (2) Due to presence of more carbon content, it form graphite flakes. (3) This graphite offers gray cast iron its characteristics looks when fractured. (4) When manufacturers form castings, molten cast iron is poured inside a mold cavity and allowed to set and slowly cool down. (5) With such slowly cooling technique, foundries can achieve crack-free or defect-less castings. It is necessary to keep the casting at cool place during or after welding process.

Page 5: How Foundries Perform Welding Of Cast Iron Castings?

Images of Cast Iron Castings

Page 6: How Foundries Perform Welding Of Cast Iron Castings?

Welding Techniques With Preheat

Performing preheating process for cast iron parts prior welding will slow down the cooling rate of the weld and its surrounded region. As per experts, one should heat the entire casting and preheat temperature should be range from 500° F to 1200° F. Overheating will make the temperature critical for casting part. It is important to preheat the part uniformly and slowly to reduce cracking tendencies.

Page 7: How Foundries Perform Welding Of Cast Iron Castings?

Welding Techniques Without Preheat

The size and other circumstances influence engineers to repair castings with welding by eliminating preheat process. For this, they keep the part cool, but not cold. The casting temperature raised to 100°F and if the part is located on an engine, engineers me run it for a few minutes to attain this range of temperature. Heat the casting up to the temperature at which you can place your hand on it.

After welding, peening is necessary and you should not raise the cooling rate with compressed air or water.

Page 8: How Foundries Perform Welding Of Cast Iron Castings?

Conclusion

This is how cast iron castings foundries perform welding process. After Peening, they seal the cracks and give the perfect finish to the component.

Page 9: How Foundries Perform Welding Of Cast Iron Castings?

Contacts

Page 12: How Foundries Perform Welding Of Cast Iron Castings?

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