Technology for manufacturing large forgings of high accuracy (1985)

Rotary excavator.

Rolling line.

Alternating frames with large details of complex productions.

All these parts are made of high-strength alloy structural steels.

They are produced by steelmaking workshops of machine-building enterprises, poured into mills and various containers and, according to orders, delivered in ingots with a unit weight of up to 250 tons.

At a temperature of 1200 degrees, these ingots are subjected to forging and are the starting material for the manufacture of a wide range of large-size parts.

The press is working.

Forging of ingots is carried out by the method of free forging on universal presses of various capacities.

The operator directs the work of the press.

To maintain an optimal temperature during the forging process, the metal is repeatedly heated.

Press operator at the console.

With repeated heating, the technological costs of the metal increase.

For many types of large-sized forged parts, such waste amounts to 60-80% of the initial mass of the original ingot.

Meeting at the design bureau.

A cartoon explaining the forging of rolling rolls in four heats.

Specialists of VPTI Tyazhmash and production workers of the Uralmash association managed to partially solve the problem of reducing time and energy costs.

A technology has been developed, which is based on a set of replaceable hinged strikers, which makes it possible to exclude a long and energy-intensive precipitation operation.

The strikers are put into operation during the second heating and are designed for a strictly defined diameter of the workpiece.

They conduct a comprehensive crimping of the ingot along the entire length.

A cartoon explaining the process.

At the same time, the structure of the metal improves and the allowances for machining the workpiece are significantly reduced.

The final operations are performed on the third heating.

A cartoon explaining the disadvantages of free forging of support necks.

The development of specialists of the Novokramatorsky Machine-Building Plant association allows to reduce losses.

The method is based on a set of calibration stamps for the most common types of rolls.

Metal losses still remain prohibitively high.

On the bluming rolls, losses reach 60%.

Due to deep structural disturbances in the metal, the wear resistance of the rolls is sharply reduced.

The design bureau of the Novokramatorsky plant.

Scientists and designers of the plant have developed a new technology based on a set of narrow strikers that allow you to squeeze calibration streams at the final stage of workpiece manufacturing simultaneously with forging support necks.

All work is carried out without replacing the equipment, regardless of the number and geometric dimensions of the calibration streams.

A cartoon showing the change in the size of the workpieces.

Mechanical processing of such forgings is reduced to the removal of a relatively thin surface layer, which gives significant metal savings and greatly increases the operational properties of the rolls.

Installation of crankshafts in engines.

A significant part of the shafts is produced by conventional stamping.

To produce a crankshaft weighing about 20 tons and a length of about 10 meters, extra-large dies and heavy-duty press units would be needed.

Production of large-sized, multi-shaft shafts by hot free forging, followed by turning the knees with a wrench and a bridge crane.

With this method, up to 90% of the expensive metal went into the chips.

In addition, due to deep structural disorders in the metal, the wear resistance of finished parts was sharply reduced.

Specialists of VPTI Tyazhmash and Uralmashzavod have developed a more advanced technology for the production of large-size crankshafts.

A universal press with a capacity of 4000 tons /force, with a detachable stamper, equipped with a neck girth mechanism and a knee fixation device.

Induction furnaces for heating metal with industrial frequency currents.

Only the section of the workpiece that should be deformed is subjected to heating.

The workpiece delivered to the press area is clamped in a stamping plant that combines two metal processing processes: bending and disembarking.

A cartoon explaining these processes.

From the stamping plant, the workpiece returns to the furnaces to heat the next section and the cycle repeats.

Cartoon explaining the process of disembarking the shaft end flanges.

Blanks of super-large crankshafts are stamped using the same technology.

For this purpose, a more powerful large-sized stamping machine has been developed, designed for a universal press with a force of 10,000 tons / force.

Panorama of the workshop.

The mechanical processing of workpieces is reduced to the stripping of the chip and the removal of a thin surface layer of metal.

Installation in the crankshaft housing.

Rotary excavator.

Large-size rollers on an excavator.

Blanks for them are made in an outdated way.

Large, press operator.

Turning of the workpiece rollers.

Specialists of VPTI Tyazhmash and Uralmashzavod have developed the technology of sector stamping.

A cartoon explaining the technology of such stamping.

Less time is spent on the machining of such workpieces, metal waste is sharply reduced, and the wear resistance of finished parts increases.

Design bureau.

Furnace for casting large-capacity ingots by progressive electroslag method.

Installation of continuous casting of steel for the needs of forging production.

The work of powerful forging complexes.

Rolling mill.

Rotary excavator.