Forging Cost Reductions

Problem

When hub shapes are achieved through machining solid bar stock or flame cutting plate, waste is an inescapable part of the process.

• When machining a shape from solid bar or flame cutting plate, all excess material—material paid for—is lost.

• Machining or flame cutting means costly machine time, lowered tool life and increased freight costs for material.

• Most importantly, the uni-directional grain flow of both bar and plate increases the likelihood of failure due to fatigue.

Problem

Castings are not always economical and can extend deliveries. Machining from a large block or plate can result in excessive machine times.

• The need to manufacture dies for specifically shaped castings often result in extended deliveries
• Castings produce enlarged grain structure, which lowers mechanical properties
• Excessive costs for small quantity casting runs are incurred due to expensive molds and set-up times
• When forging to near net is not an option, machining excessive amounts of material from plate is inefficient

Problem

Centrifugal castings are not always economical and can extend deliveries.

• Heavy wall centrifugal castings often fail to meet critical I.D. surface requirements and require welding and re-machining.
• The need to manufacture dies for specially shaped centrifugals often results in extended deliveries.
• Excessive costs for small-quantity runs are incurred due to expensive molds and setup times.
• Centrifugal castings produce enlarged grain structure, which lowers mechanical properties.

Solution

Custom hollow forgings offer consistently high quality, often at lower costs and with quicker turnaround times.

• Hollow forgings are uniformly forged with guaranteed soundness regardless of section size.
• Our extensive in-house tooling enables us to forge a large variety of hollows without added costs or extended lead times.
• Setup time is nonexistent for hollow forgings, keeping costs and lead time to a minimum whether the quantity is one or one hundred.
• Our forging process produces a seamless cross section and continuous grain flow which yields the optimum combination of fatigue strength and toughness.
• The hollow forging process offers a greater variety of O.D. as well as I.D. configurations thus reducing machining time and cost.
• Using our custom engineered, in-house tooling, we are able to provide thick walled hollows with multiple steps on both the O.D. and I.D.

Problem

Flame cutting a ring from plate is not always viable when meeting material requirements, or economical.

• Material costs are increased due to removal of excess corner stock and center slug.
• As desired thickness of the ring increases, availability of plate sizes and grades drastically decreases.
• Uni-directional grain flow of plate increases susceptibility of ring to fatigue failure.

Problem

Machining a solid bar to form a step-down causes wasteful use of material, labor and time.

• When machining the step-down, all excess material, as shown here, is lost.
• Machining time, tool life and freight costs are excessive.
• Grain flow within the bar is exposed when machined, thus making the material more susceptible to fatigue failure.

Previous processing problems

Three different metalworking processes were attempted to make one ring: a forging, a casting, and a rolled and welded plate.

• The cast ring failed sonic requirements and had inclusion problems which required excessive machining and weld repair.
• Extensive welding on the fabricated ring reduced part integrity, jeopardized corrosion resistance and caused distortion of the ring's shape.

Previous processing problems

The part was previously produced as a cast ring, with high maintenance and repair costs.

• The absence of grain flow and directional strength caused part integrity problems.
• Gears were breaking in the field due to fatigue failure, shortening the service life of the product.

Previous processing problems

The past production process involved torch cutting a heavy wall ring from plate.

• Excess waste was substantial, since all corner stock and the full center slug of the plate were lost.
• Desired plate sizes and grades were sometimes difficult to obtain due to ring thickness.
• Parts were rejected due to inclusions found on the polished surface of the plate.

Previous processing problems

Part originally consisted of three components: one rolled and welded plate and two forged rings welded to the ends.

• The two different metalworking processes made the welding difficult with inconsistent results.
• Inclusions were present in the plate, requiring extensive weld repair and reinspection.
• Weld areas required expensive X-ray testing.

Previous processing problems

Previously the part was made from a cast head welded to a hot rolled bar.

• Casting proved too weak for the application, resulting in shortened product life.
• The need for welding lengthened process times.
• In the field, excessive loads on the cast head caused part failures and required subsequent repairs.

Previous processing problems

The former part was a rolled bar welded to a forged blank.

• Heating required during the welding process changed the hardness and tensile properties in the weld zone, making it necessary to re-heat treat the part.
• Cracking was occurring in the weld layer, rework was needed, and there were many failures in the field.

Previous processing problems

Formerly, a solid steel bar was bored, machined, heat treated, and then finish machined with a tapered inside diameter.

• Bar size limitations, and the need to bore out the I.D. resulted in extensive material waste.
• Excessive machining caused high costs and shortened tool life.
• Since the I.D. was not tapered prior to heat treating, core hardness could not be achieved in that area.

Previous processing problems

Off-the-shelf tubing was previously used to form this part.

• Limited available sizes often required excess machining.
• Frequent inclusions resulted in poor surface quality and low part strength, causing internal rework and high part rejections.

Previous processing problems

A centrifugal casting with a straight I.D. and single-step O.D. was formerly used.

• Failure to meet critical I.D. surface requirements often caused extensive welding and machining repair.
• High rejection rates were experienced due to poor casting integrity.
• Excessive reworking costs and failure to meet critical production deadlines were causing major problems.