JPH0350298A - Carrier-free lubricant for forging, and use thereof - Google Patents

Abstract

PURPOSE: To provide a carrier-free lubricant compsn. for powder forging wherein the amt. of smoke generated during forging operation can be decreased by incorporating at least one kind of ingredient with adhesiveness at forging temp. as an essential ingredient.

CONSTITUTION: At least one kind of ingredient with adhesiveness at a forging temp. as an essential ingredient is incorporated and pref., additionally, an ingredient selected from graphite, ceramics and metal soaps (e.g. zinc stearate) is incorporated to prepare a lubricant compsn. for powder forging which does not contain oil and carrier such as volatile org. compd at all. As the practical example of the ingredient with adhesiveness at the forging temp., natural and synthetic wax, a polymer resin with high thermal resistance (e.g. high density polyethylene), Gilsonite (R) and glass are cited. the lubricant compsn. for forging obtd. is used by a method wherein coating is applied by spraying on a die or (and) a molding material when forging of the molding material is performed in the die.

COPYRIGHT: (C)1991,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates generally to metalworking lubricants, and more particularly to forging lubricants. Additionally, the present invention relates to novel forging lubricant compositions and methods of using the compositions in hot forging metal forming materials.

BACKGROUND OF THE INVENTION Metal parts of various sizes and shapes are manufactured by several types of forging operations, and these parts are formed from raw materials consisting of very large quantities of metals and metal alloys. A large number of parts are forged from such metals and metal alloys, such as steel, aluminum, titanium, and the like.

The conditions for forging metal parts include not only the properties of the metal, but also
It varies considerably depending on the size and complexity of the part required. Small, thin, simple-shaped parts can be forged from relatively fluid metals like aluminum under less stringent conditions than are required to forge larger, more complex-shaped parts from metals like steel. Forged from certain metal.

Each forging condition requires a specific lubricant, and therefore many water, oil or organic solvent based lubricants are commonly used for various forging operations.

Many of these lubricant systems, especially those used under the most severe forging conditions, are required to avoid, as much as possible, the safety, worker health, and environmental hazards associated with their use. It forces users to make certain compromises to achieve functionality. Moreover, more stringent health and environmental guidelines are currently being implemented that require the use of lubricant systems that are either very expensive or not easily implemented. The present invention relates to these.

Conventional lubricants effective in high-performance forging operations used in producing large intricate parts from aluminum alloy feedstocks typically combine various lubricating agents with mineral oil and/or
or in a carrier containing a volatile organic solvent.

The dies used in such forging operations are maintained at high temperatures, i.e., in the range of 350<0>F to 700<0>F, to permit adequate metal flow during the forging operation.

Forging lubricants are usually supplied by spraying into the die and molding material, and due to the temperature of the system, the mineral oil and volatile organic compounds ignite instantaneously, leaving a relatively small amount of residue that actually functions as a lubricant. Only that remains. Anyone who has observed such a forging operation will know that 1. Ignition of mineral oil and volatile organic compounds produces large amounts of open flame.
flame) and that the spray flame for supplying lubricant looks like a flamethrower. Furthermore, a large amount of smoke is generated when the mineral oil and volatile organic compounds ignite and at the same time most of the lubricating agent is burned off.

In this regard, various improvements are known in the use of forging lubricants by reducing the generation of large amounts of smoke.

Similar difficulties exist when utilizing oil-based paste lubricants. Paste lubricants contain little or no volatile organic compounds, but the oil carriers they contain burn partially or completely at normal forging temperatures, causing significant smoke production.

The risks, costs, and environmental concerns associated with such forging operations are significant and are rapidly becoming greater.

In states like California, where environmental protection laws and regulations set strict standards for industrial operations, and in other states with similar environmental protection programs, smoke generated by large-scale forging operations is a major problem. It becomes.

As the Environment Agency often monitors smoke emissions through atmospheric surveys, close attention is paid to the reduction of smoke generated in forging operations. Unfortunately, this often limits efforts to evacuate smoke from buildings in which forging operations are conducted. This results in a significant reduction in air quality within the building.

For example, in the state of California, a tax would soon be levied on every gallon of volatile organic compounds released into the atmosphere, which is a significant economic consideration. More importantly, as air quality standards continue to rise, there will soon come a time when forge operators will simply be prohibited from emitting significant amounts of smoke.

The choice would then be to either find an alternative lubricant that significantly reduces the amount of smoke or to cease operations altogether.

Pond-related concerns have led to a strong demand for alternative forging lubricants.

As mentioned above, open flames occur when conventional mineral oil and volatile organic compound based lubricants are fed to a hot die. Therefore, the area adjacent to the forging operation must be equipped with effective fire protection and extinguishing equipment, such as fire extinguishers and sprinkler systems. In fact, fire extinguishers are in constant use in many forging operations and their maintenance costs are significant. Generally, hot forging operations are equipped with all types of fire protection, extinguishing and fire detection systems, which require significant capital and maintenance costs.

A problem with the use of conventional volatile organic compound-based lubricants is that they require special storage facilities due to their high flammability. This also imposes significant costs on the use of conventional lubricants.

The transportation of these flammable lubricants in special containers and special transport equipment also adds to the additional costs associated with their use.
This is another cause of danger and inconvenience.

Another disadvantage of conventional lubricant systems, due to the instantaneous ignition of oil and solvent carriers, is the fumes generated, tar-like deposits that are applied to machinery, finished products, floors, windows, and forging operations. It forms on top of almost everything else in the same building.

Apart from the aesthetic problems of such deposits, there are economic and health concerns. Many large forging operations maintain permanent steam cleaning equipment at great expense. Furthermore, the many types of combustion products generated by uncontrolled ignition of volatile organic compounds used as carriers in conventional lubricants may themselves be hazardous to human health.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a forging lubricant and method of using the same that significantly reduces the amount of smoke generated during forging operations.

A related objective is to eliminate organic carrier materials that are an essential component of conventional high performance forging lubricants.

Accordingly, it is a general object of the present invention to provide a lubricant that reduces many of the health, environmental, and safety disadvantages of conventional lubricants containing mineral oil and volatile organic compounds as carriers.

Another major object of the present invention is to reduce the need for special transportation and storage equipment required for conventional lubricants.

Other objects and advantages of the invention will be apparent to those skilled in the art from the following description and claims.

Means for Solving the Problems The most basic form of the composition of the present invention is a carrier-free powdered forging lubricant, i.e., an oil or volatile organic It is a lubricant that does not contain any compounds. Similarly, the most basic form of the method of the present invention involves applying an effective amount of a carrier-free powder lubricant composition onto at least one of the die and the molding material. This is a forging method.

The carrier-free powder forging lubricant of the present invention is lubricating at normal forging process temperatures and can be formed into a physical form that can be applied to the die and/or forming material by conventional powder coating equipment. May contain substances.

According to the present invention, there is no need to incorporate carriers based on mineral oil and/or volatile organic compounds, so the smoke generated by using conventional lubricants is greatly reduced.

The advantages of the compositions and methods of the present invention are numerous.

Elimination of the large amounts of smoke traditionally produced by the ignition of mineral oil and volatile organic compound carriers allows forging operations to continue as a business while complying with environmental laws and regulations. Additionally, forging operations can continue without incurring financial obligations such as paying taxes based on volatile organic compound emissions. In many cases, the use of the compositions and methods of the present invention allows forging operations to continue under highly regulated environmental programs that would otherwise prohibit all operations. can.

Other economic advantages of the compositions and methods of the invention are equally very important.

The weight and volume reduction that results from the removal of traditional lubricant carriers results in savings in shipping and storage costs for the product. Since the carrier-free compositions of the present invention are neither flammable nor hazardous, further savings are realized in transportation and storage costs and can be loaded and stored on ships in the same manner as other non-hazardous materials. I can do it.

Additionally, a 5-gallon cylindrical plastic container of the carrier-free powder forging lubricant of the present invention functionally replaces a 55-gallon steel drum of conventional lubricant.
Packing costs are drastically reduced.

The compositions and methods of the present invention significantly reduce the cost of installing and maintaining fire protection and extinguishing systems at the forging operation itself, and generally maintain a safer environment for humans at a much lower cost.

By using the compositions and methods of the present invention, significant savings can still be made in fees paid for fire, personnel compensation and insurance premiums.

Since the amount of carrier in conventional lubricants accounts for more than 90% of the composition on a weight and volume basis,
Removal of the carrier material reduces the cost of raw material.

The need to maintain costly and space-consuming machinery and cleaning equipment for finished products is also eliminated by the compositions of the present invention, as there is no ignition of the mineral oil and volatile organic compound carriers and little combustion residue is produced. and reduced by the use of methods.

As mentioned above, the most basic form of the composition of the present invention is
A carrier-free powdered forging lubricant. The compositions of the present invention may include materials that are lubricious at normal forging process temperatures and can be formed into a physical form that can be delivered to a die and/or molding material by conventional powder coating equipment.

Many materials are known that act to lubricate the die and maintain physical separation between the die and the molding material, and many of these are in the physical form necessary for the practice of this invention; i.e., granular at room temperature; in the form of short fibrous or powdery solids.The materials used in the compositions of the present invention can
For example, approximately 600°F to 1000°F for aluminum
°F, approximately 1500°F for steel or titanium
It is not necessary to maintain either the solid or powder state at temperatures from 2500°F to 2500°F. It is sufficient that it has a particulate shape at room temperature.

They can be supplied in the above forms by conventional powder coating equipment, even though they partially or completely melt or burn on contact with the heated die or molding material. In fact, at least one component of the carrier-free powder forging lubricant may be used to promote adhesion of the dry forging lubricant composition to the molding material and die surfaces.
Preferably, it becomes sticky when heated.

Conventional materials capable of maintaining a physical barrier between the die and molding material and acting as solid lubricants are used in the compositions of the present invention. These materials include metallic soaps, graphite, ceramics, polymeric resins with high heat resistance, natural and synthetic waxes, gilsonite,
Examples include glass and mixtures of these substances.

Among metal soaps, fatty acid soaps such as zinc stearate and sodium stearate are preferred in terms of their properties, ease of availability, and low cost.

Other metal soaps, such as tin and lithium soaps, may also be used as long as they have a similar effect.

Materials such as graphite and certain ceramic materials such as boron nitride are useful in maintaining physical separation between the die and the molding material.

While the exact mechanism of physical separation is unknown, this property appears to be due to the relative planar crystal structure of these materials.

Useful polymeric materials with high thermal resistance include poly(tetrafluoroethylene) (PTFE), high density polyethylene (HDPE), and polyvinyl chloride (PVC).

Of the natural and synthetic waxes advantageously used, relatively high molecular weight polyethylene waxes are generally preferred because of the smoothness they provide.

The glass material used in the present invention is preferably a low melting point glass, such as alumina, alumina/silica, silica,
Contains boric acid and borax.

Optionally, these glass materials may be used in the form of chopped fibers.

The average particle size of the materials present in the carrier-free powder forging lubricants of the present invention may range from about 1 (H) microns to about 70 microns, preferably from about 30 to about 40 microns. The limitations are of little importance as far as the performance of the forging lubricant composition is concerned; particle size is primarily related to the electrostatic spray equipment commonly utilized.

In the most basic form of the method of the present invention, an effective amount of carrier-
After the free powder lubricant composition is coated on at least one of the die and the molding material, the molding material is forged into the desired finished part. In general, the lubricants of the present invention can be used in conventional powder coating equipment. As is well known, powder atomization is carried out under very low pressure with such equipment. Preferably, the carrier-free powder forging lubricant is delivered by an electrostatic spray device, since there is little loss of lubricant due to the electrostatic attraction of the particles to the die and/or molding material.

The lubricant of the present invention may be applied to a heated or heating die in a manner similar to prior lubricant applications. Alternatively, the lubricant composition may be sprayed onto the cold green molding material, which is then heated to partially melt the lubricant composition and then inserted into a heated die for forging. .

Materials such as graphite and amorphous boron nitride are easier to retain on the surface of dies and molding materials than some of the other materials mentioned above due to their finely powdered, almost dust-like nature. It turns out that's not the case. Therefore, the ventilator or air flow may remove powdered forging lubricant from the die and/or molding material prior to the forging operation. Therefore, when one or more such substances are included in the lubricant of the present invention, adhesive properties such as glass, gilsonite, and polymer resins at normal forging temperatures are used to retain the lubricant on the die and molding material. It is preferable to include at least one component having the following.

EXAMPLES The following examples illustrate the compositions and methods of the present invention.

Examples 1 and 2 High wall, approximately 0° 125 inch thick boxchannels were forged from aluminum alloy stock in a wrapped die using the following compositions. The press is hydraulic, and the temperature of the molding material is 700°.
F. The die temperature was 375°F.

Example 1 Part Weight % Gilsonite 5 Zinc stearate 34 Sodium stearate 10 Graphite 17 Polyethylene wax 34 00 Example 2 Europe Weight % Gilsonite 5 Zinc stearate 34 Sodium stearate 10 Graphite 17 Amido wax 34 00 Seven parts only Forging was carried out; that is, it was not possible to select the optimum conditions for the spraying technique. However, examination of the forged parts indicated that there was good metal movement in the channel walls that completely flushed the die.

There was good miniaturization of critical component dimensions, and the part easily separated from the die without sticking. The die had some tendency to stick together, but this is normal depending on the shape of the part. The smoke levels were significantly lower than those generated using conventional solvents, oils, and graphite.Based on this limitation, the composition of Example 1 and the composition of Example 2 The compositions were observed to be superior to the composition of Example 2, although both were effective as forging lubricants.

Example 3 In a comparative example, the composition of Example 1 was evaluated using a conventional solvent-based zinc stearate forging lubricant as a standard. The press is mechanical, and the temperature of the molding material is 7.
The temperature of the 00°F1 die was 400°F.

Forty parts were forged from each composition.

Inspection of the forged parts showed good metal movement without resistance. There was good miniaturization of critical component dimensions. The part easily separated from the die without sticking and there was no lubricant residue on the part. The smoke levels when using the composition of Example 1 were much lower than the smoke generated throughout the tests reported in Examples 1 and 2.

Examples 4 and 5 The following compositions were each evaluated under the same conditions as in Example 3 and were fully satisfactory, each producing significantly less smoke than conventional solvent-based lubricants.

Example 4 Ingredients Weight % Graphite 33.0 Zinc stearate 34.5 Gilsonite
10.9 Polyethylene wax 21.19
9.5 Example 5 Ingredients Sodium Graphite Stearate Gilsonite Polyethylene Wax Weight % 23.8 33.4 23.8 9.5 Examples 6 and 7 The following carrier-free powder forging lubricant compositions also is useful for forging forming materials of aluminum and aluminum alloys: Example 6 Graphite Gilsonite Weight % 5 5 00 Example 7 Ingredients Weight % Graphite 50 Gilsonite
25 Zinc stearate
15 Examples 8-11 Other carrier-free powder forging lubricant compositions are useful for forging titanium and steel at high temperatures, including the following ingredients: Example 8 Ingredients Weight % Alumina/Silica Glass 40 Graphite 60 O0 Example 9 Ingredient Boron Nitride Borax Weight % 5 5 00 Example 10 Ingredient Graphite Borax Weight % 5 5 OO Example 1 ■ Ingredient Graphite Gilsonite Borax Weight % 0 0 0 00 Example 12 In particular, the following composition was used with good results in steel forging operations: Example 12 Ingredients Weight % Graphite 40 Gilsonite 30 Boric acid 30 00 From the above description and examples, the objects of the present invention are demonstrated. What has been achieved is clear. Although only certain embodiments have been described, other possible embodiments and various modifications will be apparent to those skilled in the art. These and other possible embodiments and modifications are considered equivalent to and within the spirit and scope of the invention.

Advantages of the Invention According to the present invention, there is no need to incorporate carriers based on mineral oil and/or volatile organic compounds, thereby significantly reducing the smoke generated by using conventional lubricants.

Because the compositions of the invention are not flammable, there is no need for special transportation and storage equipment, and the cost of installing and maintaining fire protection and extinguishing systems in forging equipment is significantly reduced;
Additionally, the need to maintain cleaning equipment is reduced, as less combustion residue is produced due to the absence of ignition of the mineral oil and volatile organic compound carriers.

Claims (25)

[Claims] (1) A carrier-free powdered forging lubricant composition characterized by containing at least one component that has adhesive properties at forging temperatures. (2) The carrier-free powder forging lubricant composition according to claim 1, which contains a component selected from the group consisting of graphite and ceramics, and a component having adhesive properties at a forging temperature. (3) The carrier-free powdered forging lubricant composition according to claim 1 or 2, which contains graphite and gilsonite. (4) Approximately 75% graphite and approximately 25% gilsonite
% by weight of the carrier-free powder forging lubricant composition according to claim 2 or 3. (5) A carrier-free powdered forging lubricant composition characterized by containing a metal soap component, a component selected from the group consisting of graphite and ceramics, and a component having adhesive properties at a forging temperature. (6) The carrier-free powdered forging lubricant composition according to claim 5, wherein the metal soap is selected from the group consisting of zinc stearate, sodium stearate, and mixtures thereof. (7) The carrier-free powder forging according to claim 5, wherein the component having adhesive properties at the forging temperature is selected from the group consisting of natural and synthetic waxes, polymer resins having high heat resistance, gilsonite, and glass. Lubricant composition. (8) The carrier-free powder forging lubricant composition according to claim 7, wherein the polymer resin is poly(tetrafluoroethylene), high-density polyethylene, polyvinyl chloride, or a mixture thereof. (9) The carrier-free powder forging lubricant composition according to claim 5, which contains zinc stearate, sodium stearate, gilsonite, graphite, and polyethylene wax. (10) 34% by weight zinc stearate, 10% by weight sodium stearate, 5% by weight Gilsonite, 17% by weight graphite and 34% by weight polyethylene wax.
The carrier-free powdered forging lubricant composition according to claim 9, comprising: (11) Zinc stearate, sodium stearate,
The carrier-free powder forging lubricant composition according to claim 5, containing gilsonite, graphite, and amide wax. (12) The carrier-free powder forging lubricant according to claim 11, which contains 34% by weight of zinc stearate, 10% by weight of sodium stearate, 5% by weight of gilsonite, 17% by weight of graphite, and 34% by weight of amide wax. Composition. (13) A claim containing about 15 to 50% by weight of a metal soap component, about 15 to 50% by weight of a component selected from the group consisting of graphite and ceramics, and about 25 to 45% by weight of a component that has adhesive properties at forging temperature. The carrier-free powdered forging lubricant composition according to item 5. (14) spraying and coating an effective amount of a carrier-free powdered lubricant composition onto at least one of the die and the molding material, the spraying being performed under substantially normal pressure; A method for forging a forming material in a die, characterized in that: 15. The method of claim 14, wherein the carrier-free powder lubricant composition is provided by electrostatic spraying. (16) (a) coating the molding material with an effective amount of the carrier-free powder lubricant composition; (b) heating the molding material to a preselected temperature; (c) applying the molding material to the die. 15. The method of claim 14, comprising the steps of: inserting the molding material into a desired shape; and (d) forging the molding material into a desired shape. (17) The carrier-free powder lubricant composition according to claim 14, wherein the carrier-free powder lubricant composition contains a first component selected from the group consisting of graphite and ceramics, and a second component having adhesive properties at a forging temperature. the method of. 18. The method of claim 17, wherein the amount of the first component is about 25-60% by weight and the amount of the second component is about 40-75% by weight. 19. The method of claim 18, wherein the carrier-free powder lubricant composition contains about 40% by weight alumina/silica glass and about 60% by weight graphite. 20. The method of claim 18, wherein the carrier-free powder lubricant composition contains about 75% by weight borax and 25% by weight boron nitride. 21. The method of claim 18, wherein the carrier-free powder lubricant composition contains about 35% by weight graphite and about 65% by weight borax. (22) spraying and coating an effective amount of a carrier-free powder lubricant composition onto at least one of the die and the molding material, the composition comprising the step of spraying and coating the die and at least one of the molding material; A method for forging a molding material in a die, comprising a component selected from the group consisting of and a component having adhesive properties at a forging temperature, and the spraying is performed under substantially normal pressure. (23) A component having adhesive properties at the above forging temperature,
23. The method of claim 22, wherein the material is selected from the group consisting of polymeric resins with high thermal resistance, natural and synthetic waxes, gilsonite and glass. (24) The method of claim 23, wherein the polymer resin is poly(tetrafluoroethylene), high density polyethylene, polyvinyl chloride, or a mixture thereof. (25) The metal soap component is zinc stearate,
23. The method of claim 22, selected from the group consisting of sodium stearate and mixtures thereof.