JPH01271492A - Solid lubricant for extrusion molding - Google Patents

Abstract

PURPOSE:To develop a solid lubricant for extrusion molding permitting simplification of an automatic device for application of a lubricant, having excellent lubricating and mold release properties and ensuring improvement of operation rate and working environment by dispersing a solid lubricant in a mixture of a binder of a particular wax material with a high temp. adhesive of a synthetic resin etc. CONSTITUTION:The present lubricant is produced by dispersing a solid lubricant in a mixture of a binder of a wax material having a m.p. of 80-150 deg.C with a high temp. adhesive of a synthetic resin etc. capable of attaining film strengthening at high temps. As the wax, there may be mentioned petroleum- based and synthetic waxes. In particular, a petroleum-based microcrystalline wax is most pref. Examples of high temp. adhesives include inorg. (glass material, phosphate, etc.) and org. (polyolefin, polyethylene, polyurethane, etc.) adhesives. In particular, a polyolefin resin is most pref. from the viewpoints of melt viscosity and hardness. As the solid lubricant, there may be mentioned a layer lattice compd., a non-layer inorg. compd, a polymeric compd., a soft metal, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a solid lubricant for extrusion processing, and more specifically, it is used for releasing a dummy block of an extrusion press from a workpiece, and for separating a container surface from a workpiece. The present invention relates to a solid lubricant that is highly effective in lubrication, mold release, lubrication between dies and workpieces, mold release, etc., and further improves the working environment by solidifying.

(Prior Art) Dummy blocks for extrusion press machines can be broadly classified into 2 to 11 types. Currently, roost-type dummy blocks are used, and they are used cyclically in the process of lubricant application, installation, extrusion, and removal.

Many devices are automated in this process. At this time, the lubricant is applied by coating or dipping.

The problem with using a roost type dummy block is that it takes time to install and remove it, so idle time cannot be shortened, resulting in poor operating efficiency, and maintenance and space are required for the dummy block circulation equipment.

In order to solve this problem, the use of fixed-type dummy blocks has recently begun. Using a fixed type dummy block reduces idle time by ~20% compared to using a roost type dummy block, improving operating efficiency and eliminating the need for a dummy block circulation device, eliminating the need for maintenance and space.

Brushing or spraying is the only way to apply lubricant to fixed type dummy blocks as long as conventional liquid or paste lubricants are used.

Liquid or paste lubricant compositions are mainly prepared by dispersing a solid lubricant in highly flammable mineral oil.1. This method cannot be said to be a preferable method because it involves the use of foreign materials, which poses safety hazards for the workplace and the environment. There are also cases where liquid lubricant is applied in 1/- stripes for automation, but in addition to the problems mentioned above, the spray nozzle is easily clogged because the solid lubricant is dispersed, and it is difficult to control the spray amount. I have a difficult problem.

Under the above circumstances, it is desired to provide a lubricant that has good lubrication and mold release, and can easily automate lubricant application, and in addition, improves the working environment.

(Problems to be Solved by the Invention) The present invention attempts to solve the following problems in conventional lubricants as described above.

a. The lubricant coating has an appropriate thickness.

For lubrication and mold release during extrusion processing, approximately 300 to 5
It is necessary to form a lubrication and release film with a uniform and appropriate thickness on the surface of the dummy block, which is at 50°C. If this film is thin, the lubrication and mold release performance will be reduced11, and if it is thick, it will be mixed into the workpiece, giving rise to adverse effects such as cracking of the product.

Byr4 Lubricant Coating Automation In order to improve the operating efficiency of the extrusion press machine and stabilize product quality by uniformizing working conditions, it is necessary to automate the 1-lubricant coating, and it must be a simple method.

Reduction of environmental pollution It is necessary to reduce the pollution caused by lubricant dripping around the workplace, mist scattering in the case of spraying, oil vapor mist, and combustion, which occur with conventional liquid lubricants. be.

In view of the above problems, the purpose of the present invention is to automate the application of a lubricant for extrusion processing, and to achieve excellent lubrication and mold release performance.
The object of the present invention is to provide a solid lubricant for extrusion processing that improves operating efficiency by shortening idle time and improving the working environment.

(Means for Solving the Problems) The present invention uses a wax-like substance with a melting point of 80 to 150°C as a binder, and disperses a solid lubricant in a high-temperature adhesive such as synthetic resin that strengthens the film at high temperatures. This relates to a solid lubricant for extrusion processing.

The wax-like substance used in the present invention solidifies at room temperature and plays the role of binding solid lubricants, and preferably has lubricating properties.Specific waxes include petroleum-based waxes (puffin wax, microcrystalline wax, etc.). etc.), synthetic systems (polyethylene wax, etc.), etc. Microcrystalline wax in particular has a high melting viscosity, is soft despite its high melting point, and has the characteristics of sharply melting and sharply solidifying, and does not sag during use. Further, even if a solid lubricant is dispersed, the mechanical strength is not weakened and cracking does not easily occur. When using a wax-like substance with a melting point in a specific range of 80 to 150°C, it is desirable to have a melting point 30 to 40°C higher than the environmental temperature of the extrusion process so as not to melt at the environmental temperature.
This is because if the melting point is too high (if it comes into contact with the dummy block and melts), rapid melting will not be obtained and this will be a hindrance to the work.

Inorganic and organic adhesives can be used as the high-temperature adhesive in the present invention. High-temperature adhesives play the role of firmly adhering to the dummy block surface and improving the film strength. However, inorganic adhesives (plus substances, phosphates, etc.) have too strong an adhesive force, so if the usage conditions are incorrect, they may cause lubrication and release surface. There is a risk of accumulation. From this point of view, there are various organic thermoplastic hydrocarbon resins such as goliolefin, polyethylene, polyurethane, and epoxy resins, but polyolefin resins are suitable in terms of melt viscosity, hardness, etc.

Next, the solid lubricant used in the present invention must have appropriate lubricity, be stable without causing physical or chemical alteration, be free from corrosion or other harmful effects, and be compatible with lubricating surface materials. It is sufficient to satisfy conditions such as not having an undesirable effect on the surrounding environment, and materials that meet these conditions include layered lattice compounds (graphite, MoS2, BN, WS2).
．． graphite heptadide, mica, etc.), non-layered inorganic materials (PbO, Zn
O.

M o Os, S iN 4. CaFi, etc.), polymer compounds (polytetrafluoroethylene, organic molybdenum, melamine shea slate (MCA), polyimide, polyacetal, etc.), soft metals (gold, silver, lead, tin, zinc, etc.), and the like can be used.

The high temperature adhesive used in the present invention increases the melt viscosity, provides lubrication,
The objective is to increase the thickness of the coating on the mold release surface. Another purpose is to assist the chicken-tropic properties of solid lubricants.

In the present invention, 10 to 100 parts by weight of the high-temperature adhesive is added to the binder, preferably 10 to 50 parts by weight, per 100 parts by weight of the binder. If this happens, the melt viscosity will increase and the film thickness will become too thick, and the solidification during cooling will not be sharp, causing liquid blurring.

The role of solid lubricants is lubrication at high temperatures.#! It has a mold effect, provides lubrication, and gives chicken-tropic properties to the mold release film.
The purpose is to appropriately control the thickness of the L film If1. To give chicken tropism, oil absorption of homogeneous lubricant is required.
The higher the value, the better, and the oil absorption value is 30et! / 100F
The particle size is preferably 1 or more, and the particle diameter is preferably 50 μm or less based on the specific surface area, and 20 μm or less, particularly 10 μm or less. The amount added is preferably 50% or less; if it exceeds 50%, the mechanical strength will decrease and the chicken tropism will become strong, and the product will be affected by excessive adhesion to lubricating and type III surfaces.

When using the solid lubricant of the present invention, for example, press the solid lubricant onto the liquid-processing material contact surface of a fix-type dummy block for extrusion blending while rotating it. It lubricates surfaces and improves mold releasability.

Next, the present invention will be explained with reference to the drawings.

Figure 1 shows an example using the solid lubricant M of the present invention.
An example of me applied to the contact surface between a fix-type dummy block of an extrusion Buns machine and a billet as a workpiece is shown.

In FIG. 1, 5 is an extrusion stem of an extrusion press machine, and 6 is a fix type gummy block attached to the tip j11 of the extrusion stem 5 with a bolt or the like. 1 is a solid lubricant according to the present invention, 21i is a holding member for the solid lubricant M1, 3 is a plate, and 4 is an arm that rotatably holds the plate 3 at its tip, and the rear 18 parts of the arm 4 are not shown. It is attached to a fixed part so that it can swing and move forward. As a rotating device for the plate 3, although not shown, ta*
or a chain is installed in the arm 4 and connected to an external rotation drive device, or the end of the arm 4 is connected to the plate 3.
A motor is attached directly to the rotating shaft.

When lubricating a fixed-type gummy block 6, swing the arm 4 in a direction perpendicular to the plane of the paper and apply the solid lubricant 1 to the fixed-type dummy block 6 as shown in Figure @1.
Place it on the entire surface. In this state, the arm 4 is advanced in the tangential direction of the fixed type gummy block 6 while rotating the plate 3, and the rotating solid lubricant 1 is pressed against the surface of the fixed type dummy block 6 to lubricate it.

In this case, the solid lubricant 1 may be a plurality of solid lubricants as shown in FIG. After the arm 4 is moved backward and swung to a position where it does not interfere with the extrusion operation, the extrusion operation is performed.

(Examples) The present invention and its effects will be specifically explained below in more detail with reference to Examples.

Example 1 100 parts of microcrystalline wax at 150°C
Then, 10 parts by weight of GRA7I) having an average particle size of 7 μm is added, and the mixture is stirred under reduced pressure. While maintaining the temperature at 150°C, 10 parts by weight of polyethylene resin is added and melted. After lowering the temperature to 120°C, the mixture was poured into a mold and solidified by cooling to obtain a solid lubricant.

Examples 2 to 6 and Comparative Examples 1 to 3 Solid lubricants were obtained in the same manner as in Example 1 using each component listed in Table 1.

Comparative Example 3 was carried out using a commercially available mineral oil lubricant.

The melt viscosity was measured using a B-type viscometer (rotation IL: 12 rpm), and the swelling coefficient was measured using a B-type viscometer at a rotation speed of 6 rpm.
It was calculated by dividing the viscosity value at + by the viscosity value at 60 rpm. The performance evaluation test results of the formulations obtained in Examples 1 to 6 and Comparative Examples 1 to 3 are shown in Tables 2 and 3.

Performance evaluation test Aluminum extrusion processing was performed and the lubrication, mold release effect, appearance of processed products, internal effects, and working environment were evaluated.

The lubrication and mold release effects were determined by visually observing the degree of abrasion of the dummy and the degree of aluminum adhesion.

The display method was divided into the following three stages.

O No problem Δ Slight problem X Problem found Test 1 Performance evaluation was performed by applying lubricant once every 3 shots (hand application).

Table 2 High Temperature Welding When the amount of polyethylene resin and solid lubricant with chicken tropism added increases, the film thickness increases, which affects the inside and outside of the product.

Furthermore, as shown in Comparative Example 2, if the amount of polyethylene resin added is too high, it becomes hard, the melting rate is slow, an appropriate coating thickness cannot be obtained, and the lubrication and mold release effects become weak.

Test 2 Performance evaluation was performed by applying lubricant once every 8 shots (hand application).

Table 3: Products with low swelling coefficients and weak film strength have weak lubrication and mold release effects. However, Comparative Example 2 is an exception. or,
In Comparative Example 1, in which the swelling coefficient is too high, the coating thickness is still too thick.

Test 3 Performance evaluation was performed by applying lubricant once every 8 shots (automatic application).

Table 4: In the case of automatic machine application, compared to hand application, pressing requires higher pressure (and melts more).Thus, materials with a low swelling coefficient will melt excessively, causing dripping in areas other than the required areas and contaminating the surrounding area. .

As is clear from the above table, the solid lubricant of the present invention has superior lubrication and mold release effects compared to conventionally used mineral oil-based lubricants, does not affect products, and improves the working environment. Automation is possible with easy-to-use automation equipment,
It has a tremendous effect.

(Effects of the Invention) The solid lubricant for extrusion processing according to the present invention solves problems that were previously expected but could not be achieved, and by making the type of lubricant solid, automation equipment can be improved. It is simple, does not affect idle time, and has advantages such as improving the working environment.

That is, the lubricant of the present invention is compatible with the mechanical conditions, material conditions, and working conditions in extrusion processing by combining a binder, a high-temperature adhesive, and a solid lubricant, and the lubricant and mold release effects are compatible with the usage conditions. By solidifying it, you can obtain a product with improved working environment.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing an embodiment of a device using the solid lubricant of the present invention. 1...solid lubricant,
2... Holding member, 3... Plate, 4
......7-A, 5...Extruded stem, 6.
...It is a fixed type gummy block. (That's all) Applicant Matsumura Oil Research Institute Ube 9! ! Representative of Sansan Co., Ltd. Patent attorney 1) Iwadai Mura,
Figure 1 + 1 Solid lubricant 2 Holding member 3 Plate 4 Arm 5 Extruded stem 6 Fix dummy block

Claims (1)

[Claims] (1) A solid lubricant for extrusion processing in which a solid lubricant is dispersed in a high-temperature adhesive such as a synthetic resin that uses a wax-like substance with a melting point of 80 to 150°C as a binder and strengthens the coating at high temperatures.