A Step-by-Step Guide to Closed Die Steel Forging Parts Manufacturing

Forging has always been regarded as the foundation of the manufacturing sector. It is a significant input to industries including automobiles, industrial machinery, power, construction and mining equipment, railroads, and general engineering that sustain the nation's economic prosperity. For its technical prowess, the Indian forging sector is well-known on a global scale. The Indian forging industry has the potential to forge a variety of raw materials, including stainless steel, super alloy, carbon steel, alloy steel, titanium, aluminium, and so forth, depending on the demands of the user industry. This industry's installed capacity is around 38.5 lakh MT.

The Indian forging industry has witnessed a sea change over time from being labour-intensive to capital-intensive. The present plant and equipment investment made by Indian forging business leaders is around INR 27,833 crore. The forging units can be categorized as stated below:

• Large (capacity above 30,000 to 75,000 MT)
• Medium (capacity above 12,500 to 30,000 MT)
• Small (capacity above 5,000 to 12,500 MT), or
• Very small (capacity up to 5,000 MT) based on their installed capacities.

As per the classification above, it can be seen that 83% of all units are small or very small, compared to just 8% that may be categorized as very large or giant, and the remaining 9% that make up medium-sized units.

This blog further sheds light on the steel forging process adopted by the top steel forging manufacturers in India to produce a comprehensive range of products making use of steel forgings using the closed die forging technique:

1. Designing & creating dies

Making dies is a procedure that is not necessary for closed die steel forging parts. Once a new order is placed, the engineers involved will create dies using the customer's steel forging drawing. Forging dies are substantially more expensive than casting molds since they include forging dies, trimming dies, and flattening dies, unlike casting.

2. Cutting and heating the billet

For continuous manufacturing, forging manufacturers in India maintain some typical steel material specifications on hand in the forging facility. Following the completion of the dies, steel billets are removed from the material warehouse, chopped to the desired length, and heated in a medium-frequency furnace before forging.

3. Closed Die Forging

Heat-treated steel bars that are placed under upper and lower dies and then pressed into the desired shape after being heated from billets are known as flash.

4. Trimming

Now that forging blanks with flash have been acquired, the flash is removed by pressing the steel blanks once more while being placed under trimming dies. A complete forging blank is finished in this step.

5. Heat Treatment

After forging, heat treatment is carried out to enhance the strength and mechanical qualities. Common heat treatment techniques for steel forgings include normalizing, quenching, annealing, tempering & hardening, solution treatment, etc., just like they are for investment castings. Naturally, heat treatment is only used when necessary.

6. Shot blasting

Steel forgings are shot blasted by the fabrication manufacturing company to get rid of the scale and get a superior surface finish. After shot blasting, products appear considerably more smooth and transparent.

7. Machining

Although forging blanks have tighter tolerances than casting ones, occasionally this is still insufficient for application; in these circumstances, machining is required. The NC lathe and CNC are the primary machining tools used in the forging facilities. While CNC is used for precise, expensive machining, NC lathes are utilized for simple machining. The process takes place in an extremely sophisticated facility equipped with the following tools and machines:

• 2 Con-rod Machining Lines
• Daimler Support Arms Machining Line
• Hub Machining Line
• CNC Machining Centers
• Vertical Turning Lathes
• Flexible machining centers
• Multi-machine manning
• Hydraulic fixture for quick clamping / de-clamping
• In-process gauging
• Special Gauges for Con Rods

8. Surface Treatment

When it comes to packaging, water/oil anti-rust painting is sufficient if specific surface treatment is not needed. Depending on how steel forgings are used, further particular surface treatments, such as color painting, zinc plating, electro painting, etc., may be carried out.

9. Inspection

An additional crucial phase is inspection. The inspection procedure can be divided into internal and external inspections. Dimension testing and visual flaw assessment are included in the external inspection. Internal inspection also refers to an inspection of internal qualities.

10. Delivery of the package

For steel forgings that are to be exported, top steel forging manufacturers in India package the goods in ploybags before placing them in a typical wooden case to prevent damage. Additionally, the manufacturers can alter a package to meet the needs of the customer.

Below are some good examples of the products produced via the forging process:

• Spring Clamp Plates, Mounting Brackets, and Tow Hook
• Spindle Lock Nut, Drive Shafts, and Final Gear
• Transmission Shafts and Eye Shafts
• Pinions and Input, Output Shafts
• Wheel Hub, Rack Piston, and Drop Arm
• Crankshafts, Connecting Rods, Steering Knuckles, and Wheel Hubs
• Brackets, Connectors, Flanges, and Valve Segments
• Steering Arms, Pitman Arms and Tie Rods
• Sector Shaft, Cylinder Cover, and Worm Cover
• Gears, Support Arms, and Helper Spring Plate
• Balancer and Cam Shafts.

In India, the forging industry directly employs more than 95,000 people. The medium and large units are more mechanical, but the mid-size and small units rely primarily on manual labor. The industry's quality standards have substantially increased, and it is now recognized internationally for its high quality. Currently, the automotive sector only makes up around 58% of all forging production; the remainder is produced by non-auto industries. Since forging components are the foundation of the Indian automotive industry, changes have a direct impact on the forging sector in India.

Concluding Remarks

Caparo’s forging division is India’s leading fabrication manufacturing company. This significant division of the company was established in 2009 to manufacture and supply a comprehensive range of forged and machined products including Crankshafts, Connecting Rods, Support Arms, and other components for a variety of automotive and non-automotive applications. Caparo forging is the preferred partner for leading names in the industry such as Iljin, Daimler, Rane TRW, Woosu, AVTEC, Royal Enfield, Delphi TVS, CAT, Simpson & Co Ltd, and many more.