JP2002220596A - Stabilizer for clamping force of fastening body, method for stabilizing clamping force using the same, and stabilizer-adhered component part for fastening body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stabilizer for clamping force capable of controlling fluctuation of a torque coefficient suitable for managing the clamping force of a fastening body in a torque method as possible. SOLUTION: Disclosed is a stabilizer for a fastening body comprising conducting fastening working after making a polymer of an unsaturated linear hydrocarbon having carbon number 4 as an active ingredient adhere to at least either one of a screw element, a washer a screwing part of screw of a fastened body or a washer-contact surface of bolt members or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stabilizer capable of stabilizing the tightening force of a fastener, a method for stabilizing the tightening force of a fastener using the same, and a method of pre-adhering the stabilizer. The present invention relates to a component that constitutes a fastening body formed by the above method. Here, the “parts forming the fastening body (fastening body constituent parts)” refers to a bolt member formed with a male screw and a nut member formed with a female screw, which are screw parts to be screwed together, such as a bolt, a screw, and a nut. , Pipe joints, etc., and also includes washers, washers, and objects to be fastened, which are used as an auxiliary to the fastener. The terms used in this specification conform to the general rules for screw tightening (JIS B1083) and screw terms (JIS B0101).

[0002]

2. Description of the Related Art Screw tightening is performed according to JIS B108.
3 has general rules. FIG. 8 is a graph showing the relationship between the elongation of the bolt and the tightening axial force. FIG. 8 is a graph showing the relationship between the elongation of the bolt and the tightening axial force. It changes linearly. In the elastic region, the relationship between the tightening torque Tf and the tightening force Ff is expressed by the following equation (1).

Tf = Ts + Tw = K · Ff · d (Equation 1) Here, K, Ts, and Tw in Equation (1) are as follows.

K = (1 / 2d) · ((P / π) + μs · d2 · sec α ′ + μwDw) (Equation 2) Ts = (Ff / 2) · ((P / π) + μs · d2 · sec α ′) (Equation 3) Tw = (Ff / 2) · μw Dw (Equation 4) When the contact surface (including the case of using a washer) is annular, Dw in the expression (4) is It is given by the following equation (5).

Dw = (2/3) · ((Do3-Di3) / (Do2-Di2)) (Formula 5) The symbols in the above formulas and their meanings are as follows.

Dw: equivalent diameter of friction torque on the bearing surface Di: inner diameter of the bearing surface in contact Do: outer diameter of the bearing surface in contact Ff: initial tightening force or tightening force K: torque coefficient P: screw pitch Tf: tightening Torque Ts: Thread torque Tw: Seat torque d: Nominal diameter of screw d2: Effective diameter of screw α: Flank flank angle of thread α ': Flank angle (tan α)
´ = tan α ・ cos β) β: Lead angle of thread μs: Friction coefficient of thread surface μw: Friction coefficient of bearing surface By the way, the management of the tightening force of the fastener is important to give the required strength to the fastener. As a management method, a torque method, a rotation angle method, and a torque gradient method are generally known, but a torque method that manages only a tightening torque during a tightening operation has an advantage that a special tightening tool is not required. Therefore, in practical use, this torque method is widely used.

However, around 90% of the tightening torque Tf is consumed by the friction between the screw surface and the seat surface, and the initial tightening force largely depends on the friction and the contact state between the screw surface and the seat surface during the tightening operation. There is a problem that is.

That is, when the following (Formula 1 ′) Ff = Tf / K · d (Formula 1 ′) obtained by modifying the above (Formula 1), the tightening force (tightening axial force) Ff is It is directly proportional to the torque Tf, the torque coefficient K and the nominal diameter d of the screw.
It can be seen that it is inversely proportional to
When a large number of the same fastening members are formed by using a nut member, the nominal diameter d of the screws is the same (basically the same diameter even though there is a slight difference of a tolerance), so that a fixed tightening torque Tf In the case where the tightening is performed, if the torque coefficient K is constant, a constant tightening force (tightening axial force) Ff should be always obtained. However, in practice, a certain tightening force is not always obtained when a tightening operation of a bolt-nut fastener of the same standard is performed with a certain tightening torque.

[0009] This is because the tightening force of the fastening member between the bolt member and the nut member is different from the usual friction, wear, and lubrication in the machine and machining fields, and the variety of friction and contact between the screwing surface and the bearing surface of the screw is different. Because they are susceptible to specificity. For example, if galling or seizure occurs partially on the screwing surface or seating surface of the screw, there is a problem that the frictional state becomes non-uniform and the torque coefficient changes. It is.

That is, in order to stably obtain the screw tightening force indirectly by the tightening force as in the case of the torque method, it is necessary to sufficiently consider the diversification and specificity of the friction and contact between the screw surface and the seat surface. However, if galling or seizure occurs partially on the screw surface or seat surface and the friction state becomes uneven, not only the friction coefficient of the screw surface or seat surface changes, but also the friction torque on the screw surface or seat surface. Factors such as the equivalent diameter and the effective diameter of the screw are also affected, leading to fluctuations in tightening characteristics and instability.

FIG. 9 shows a state in which the tightening axial force Ff changes due to the change in the torque coefficient K. If the tightening torque Tf further changes, the difference between the maximum axial force Ffmax and the minimum Ffmin is shown. Is considerably large, and it can be seen that this is a great obstacle to obtaining a stable tightening force during the fastening operation.

[0012] Under the circumstances described above, a contrivance has been made to stably obtain a constant tightening force by controlling the tightening torque.

Conventional techniques for stabilizing the tightening force of a fastening body by a torque method include: 1) a method of applying a paste containing machine oil or solid lubricating powder.

2) A method of coating a powder of molybdenum disulfide or PTFE (polytetrafluoroethylene or tetrafluoroethylene) with a resin binder or the like (JP-A-50-139256, JP-A-10-338824)
No.).

3) A method of performing a bonderite / bonder-lube treatment (Japanese Patent Application Laid-Open No. 49-81237).

4) A method of dipping and applying low-molecular-weight oxidized polyethylene dispersed in water and a synthetic resin emulsion, followed by drying and coating (Japanese Unexamined Patent Publication No. 9-40991). 5) Coating by coating graphite powder with an epoxy resin or the like. (Japanese Unexamined Patent Application Publication No. 08-28535,
0-120638).

6) A method of applying a resin dispersed or dissolved in water or the like, followed by drying and coating.

The method 6) is disclosed in Japanese Patent Laid-Open No. 52-0814.
No. 62, JP-A-52-149566, JP-A-55-60711, JP-A-55-062985, JP-A-56-041285, and JP-A-06-06.
080983, JP-A-07-224824 and the like.

[0019]

Here, "stabilization" means that the tightening torque is measured while the tightening axial force is constant.
The average torque coefficient Km is determined from the equation (1), and the variation (standard deviation Sk of the torque coefficient, variation coefficient B) is calculated.
The case where the variation is relatively small is referred to as “stable”, and the case where the variation is large is referred to as “unstable”.

B = Sk / Km (Equation 6) B: Coefficient of variation of torque coefficient Sk: Standard deviation of torque coefficient Km: Average torque coefficient Considering the prior art from the viewpoint of “stabilization”, The method of simply applying a mineral oil (machine oil) 1) or the method of coating the powder of the above 2) with a resin binder is as follows.
Stabilization of tightening force and torque coefficient is not enough.
Temperature has a large effect on tightening characteristics, and although friction resistance can be reduced, it does not act as a stabilizer,
The object of the present invention cannot be achieved.

In other words, the method using the attachment of the mineral oil or the paste containing the solid lubricating powder has the effect of reducing the frictional surface resistance, but is not effective for the above-mentioned stabilization.

In addition, the stabilizer is expensive.
In the method using solid lubricating powder, there is a problem that solid powder and oil are easily separated from the difference in specific gravity when left unattended,
Furthermore, once tightened, the solid powder deforms or breaks,
If tightening and loosening are repeatedly performed, there is a problem in that a tightening characteristic is changed due to a running-in effect, resulting in instability. The reason for "repetition of tightening and loosening" is that, for example, in the case of maintenance in the field of chemical plants and nuclear power plants, aircraft and railways, and also in the repair and replacement of tires in automobiles, disassembling and reassembling are performed repeatedly. This is because it is necessary to repeat the tightening and loosening.

The above methods 3) to 6) are used for stabilizing the tightening force of the fastening body, but each has problems.
For example, the method of performing the bonderite-bonder-lube processing among the above methods has a problem that the sensitivity to temperature is high and the torque coefficient value greatly changes due to the temperature change.

According to the method (4) of dipping, coating, and drying the water-dispersed oxidized low-molecular-weight polyethylene and the synthetic resin emulsion (JP-A-9-40991), 1) it is not dissolved in an organic solvent. Therefore, it is difficult to uniformly disperse the stabilizing substance in water, and the film characteristics such as the film thickness formed on the fastener differ depending on the dispersion state, and the torque coefficient varies.

2) If dissolved in an organic solvent, it will volatilize and can be used immediately after spraying. However, since a drying device is required to dry water, aerosol (spray)
Even if it is used, there is a problem that it cannot be used immediately after spraying the fastener on site.

According to the method (5) of coating and coating the graphite powder together with the epoxy resin (JP-A-08-28535 and JP-A-2000-120538), the graphite powder reduces the friction coefficient and causes The fastening body is likely to be loosened. Further, there is a problem that the torque coefficient changes depending on the dispersion state and the particle size of the graphite powder, and the dispersion increases.

Furthermore, the method (6) of applying a resin dispersed or dissolved in water or the like and drying and coating (hereinafter referred to as "solid coating type") has the following problems. [B] Insufficient stabilization. [B] Special processing equipment is required and is not suitable for small-lot production. [C] The coating film thickness affects the tightening characteristics. [D] The coating peels off during contact or screwing during transportation. [E] The coating peels off due to repeated loosening of the tightening, and the tightening characteristics change. [D] Tightening characteristics change due to deposits such as water and oil.

As described above, any of the prior art methods for stabilizing the fastening body fastening force have problems.

The present invention solves these problems and provides a tightening force capable of suppressing fluctuations in a torque coefficient suitable for controlling the tightening force of a fastening body by a practically superior torque method. It is intended to provide a stabilizer.

Another object of the present invention is to provide a method for stabilizing the fastening force of a fastening body, which can stably obtain the fastening force of the fastening body by using the fastening force stabilizer.

Still another object of the present invention is to attach the above-mentioned tightening force stabilizer to a fastener body component in advance at a factory or the like where the fastener body component is manufactured or shipped, and mechanically attach the fastener body. It is an object of the present invention to provide a fastener component with a stabilizer attached thereto, which is supplied to an assembly factory or the like.

[0032]

The object of the present invention is attained by the inventions having the following constitutions. In the present invention, the term “fastened body” refers to “screw-fastened body” of JIS B1083. (1) A fastener tightening force stabilizer comprising a polymer of an unsaturated chain hydrocarbon having 4 carbon atoms as an active ingredient of the stabilizer. (2) The polymer of an unsaturated chain hydrocarbon having 4 carbon atoms is n-
Any one of a butene polymer, an isobutene polymer, a copolymer of n-butene and isobutene, or a mixture thereof, wherein the fastener fastening force stabilizer according to the above invention (1) is used. . (3) The fastener tightening force stabilizer according to the invention (1) or (2), wherein the active ingredient of the stabilizer is dissolved in mineral oil in an amount of 10% by mass or more. (4) The fastener tightening force stabilizer according to any one of the inventions (1) to (3), wherein an active ingredient of the stabilizer is dissolved in an organic solvent.

(5) The active ingredient is ASTM D25
The fastener tightening force stabilizer according to any one of the above inventions (1) and (2), wherein the number average molecular weight measured in 03-92 is 5,000 or less. (6) The active ingredient is an NPCC method (NIPPON PETROCHE
The stabilizer for tightening force of the above-mentioned invention (1) or (2), wherein the weight average molecular weight measured by MICALS Method (GPC) is 50,000 or more. (7) The fastener tightening force stabilizer according to any one of the above-mentioned inventions (1) to (6), wherein the viscosity of the stabilizer is adjusted to be 235 mPa · s or more at the environmental temperature during the fastening operation of the fastener. (8) At least one of a screw member such as a bolt member and a nut member and a screw threaded portion of a member to be fastened, and a screw member such as a bolt member and a nut member and a seat surface of a washer and a member to be fastened are described above. A method for stabilizing a fastening body fastening force, wherein the stabilizer according to any one of the inventions (1) to (7) is adhered and used. (9) The fastening force stabilizing agent according to any one of the inventions (1) to (7) is previously attached to at least one of the screw part and the washer, the screwed portion of the object to be fastened, or the seat surface. A fastener constituting part of the fastener, wherein the fastener is stored. (10) The above invention (1), (2), (3) or (5),
(9) The invention according to the above (9), which comprises forming a coating by dissolving an active ingredient of the stabilizer of any one of (6) and (7) in an organic solvent and then evaporating the organic solvent. 3. The fastening member component according to claim 1. (11) The fastening member component having the fastening force stabilizing agent according to any one of the inventions (1) to (7) adhered to the surface is a screw member such as a bolt member or a nut, or a washer and a fastened member. A fastener component constituting a fastener, which is at least one of the above.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION In the above invention (1), the olefinic hydrocarbon butene (also referred to as butylene) of the invention (2) is preferably used as the unsaturated chain hydrocarbon having 4 carbon atoms. Any of butene and isobutene may be used. The polymer (polybutene) may be a homopolymer thereof (polymer), a copolymer thereof (copolymer), or a homopolymer of these polymers or copolymer. (Note that in the following description, polybutene (polymer) includes a single polymer, a copolymer, or a mixture except for the description in Examples.)

The polybutene used in the present invention preferably has a number average molecular weight Mn of 300 or more, a viscosity average molecular weight Mv of 1 × 10 ⁷ or less, more preferably a number average molecular weight Mn of 500 or more, and a viscosity average molecular weight Mn of 500 or more. Mv is 6 × 10
⁶ or less is often appropriate. If the average molecular weight is too small, the coefficient of variation of the torque coefficient, which will be described later, tends to increase, and the risk increases because the flash point decreases. Conversely, if the average molecular weight is too large, the stabilizing substance becomes hard, and the frictional resistance on the screw surface and the bearing surface and the torque coefficient become too large. When the average molecular weight is further increased, the stabilizing substance is solidified and broken by the force applied to the screw surface and the seat surface, and the variation in the torque coefficient is increased.

As such polybutene, for example,
Glissopal 1000, 1300, 2300: manufactured by BSF Ltd. (hereinafter referred to as "BASF"):
Weight average molecular weight 1000-2300 by GPC (gel permeation chromatgraphy) method, TETRAX 3
T, 4T, 5T, 6T: Nippon Petrochemical Co., Ltd .: NP
Weight average molecular weight 66000 to 1290 by CCC method (GPC)
00, Idemitsu polybutene OH, 5H, 2000H (hydrogenated grade), 15R, 35R, 100R, 300R (hydrogen-free grade): manufactured by Idemitsu Petrochemical Co., Ltd .: number average molecular weight of 350 to 3000 by ASTM D2503-92, etc. Can be mentioned as a representative.

In order to avoid a seizure phenomenon when the fastener is used at a high temperature, a solid lubricant may be added to and mixed with the fastener tightening force stabilizer of the present invention.

When the viscosity is high and the adhesion is difficult and the workability is poor, a polymer of n-butene, a polymer of isobutene, a copolymer of isobutene and n-butene, or a mixed composition thereof is used. May be dissolved in an appropriate solvent to adjust the viscosity, or a mixed composition obtained by mixing two or more of a polymer of n-butene, a polymer of isobutene, or a copolymer of n-butene and isobutene The substance can be used as an emulsion using a surfactant in an incompatible dispersion medium (for example, water).

In the above description, the stabilizer containing a butene polymer (polybutene) as an active ingredient is compatible with, for example, mineral oil and adheres to bolt members or the like, or is dissolved in an organic solvent and adheres to bolt members or the like. Before or after deposition, the solvent can be used by drying to volatilize and remove the solvent. When the former mineral oil is used as a compatibilizer, it is preferable to use the active ingredient of the stabilizer as a compatible component in mineral oil of 10% by mass or more as in the above invention (3). If the amount of compatibility is less than this, the tendency for the coefficient of variation to increase increases, making it difficult to achieve the object of the present invention. In the latter case where an organic solvent is used, a volatile solvent that can dissolve the butene polymer and can be used is not limited, and for example, toluene, hexane, or the like can be used. When these organic solvents are used as a solvent, the solvent can be volatilized and removed by drying. Examples of the mineral oil include neutral oils and bright stocks obtained by distilling and separating paraffinic, naphthenic, and intermediate group mineral oils and subjecting them to hydrorefining or solvent refining treatment. The solvent dewaxed oil,
It can be used as an oil from which hydrogen has been further refined under high pressure to remove impurities such as sulfur, and is not limited thereto.
As long as it is used for general screw tightening, it can be used. In particular, machine oil (ISO VG46)
Can be mentioned as a representative.

The addition of an agent for another purpose as necessary to the stabilizer of the present invention is not excluded. Such additives include, for example, extreme pressure additives,
Defoaming agents, coloring agents for facilitating visual confirmation of the presence or absence of adhesion, and the like can be given.In general, the amount of these additives is very small, and stabilizes the tightening force of the present invention. The effect of the coefficient of variation B is substantially negligible.

In the stabilizer of the present invention, depending on the difference in the average molecular weight, the properties of the adhesion layer such as a film formed on the screw surface or the like are liquid, soft viscous, or rubber.

In the present invention, the term "rubber-like" refers to a viscous substance and a rubber-like (excluding Table 5).

Such a difference in the properties of the coating greatly affects the use of the stabilizer of the present invention.
In applications where large numbers are used, such as in the automotive industry, it is often not appropriate to perform the work of attaching a stabilizer at the work site for the production of fasteners. It is preferable to manufacture and provide in advance as a product to which a stabilizer has been attached at a factory or the like. For this reason, a stabilizer prepared by mixing a butene polymer having a weight-average molecular weight of 50,000 or more with a rubber-like property while being attached to the surface of a bolt member or the like is suitable. Conversely, when using a small number of fasteners, it is preferable to apply the stabilizer at the assembly work site rather than the workability of adhesion to the surface of the bolt member, etc. Those having an average molecular weight of 5000 or less are suitable. Those having a weight-average molecular weight of more than 5,000 and less than 30,000 can be used to obtain any effect of a method of performing an adhesion work in a factory or a method of performing an adhesion work in a field. Coating: weight average molecular weight 50,000
Above) or a liquid adhesion layer (number average molecular weight 5000)
The following effects will be used eclectically.

When a mixture of n-butene, isobutene, a polymer and a copolymer of these simple substances is used, the average molecular weight of each butene constituting the mixture may be the same or different. . The use of a mixture of materials having significantly different average molecular weights has the advantage that the viscosity and the range of stabilizing properties at the temperature of use can be widened. Further, the same butene polymer (polybutene) having the same composition may be used as a mixture of polymers having different average molecular weights (for example, isobutene having an average molecular weight of several thousand and tens of thousands of isobutene). The range of preparation of the stabilizing properties can be widened.

In the above description, the term “adhesion” is not particularly limited as long as the stabilizer can be coated on a target surface (screw surface or the like), and application, dipping (dipping), spraying, or the like using a brush or the like is possible. Any of these may be used.

Depending on the surface condition of the fastener, an extreme pressure additive (see "Physical Chemistry of Lubrication", pp. 226 to 229: 1974, see Koshobo :), a defoamer or the like can be used to stabilize the fastening force of the fastener according to the present invention. The stabilizer may be added, or another suitable additive may be added if there is no problem in the properties of the stabilizer. In order to make it easy to visually check the presence or absence of adhesion, a coloring agent (pigment,
Dyes) may be added to the fastener tightening force stabilizer of the present invention.

[0047]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a fastener tightening force stabilizer of the present invention, a fastener tightening force stabilizing method of the present invention, and a fastener component to which the tightening force stabilizer of the present invention is attached will be described. Although described with reference to the accompanying drawings, the present invention is not limited to this embodiment.

After applying the lubricants and stabilizers of Examples and Comparative Examples of various tightening force stabilizers to bolts, nuts and washers (hereinafter referred to as “bolts”), the following conditions are satisfied. A fastening test was performed below, and the fastening body fastening force stabilizing characteristics were compared. In the present invention, the average molecular weight is measured according to ASTM D2503-92 when the number average molecular weight Mn is 5000 or less, and when the number average molecular weight Mn exceeds 5000, the weight average molecular weight Mw is measured by the NPCC method (GPC). The weight average molecular weight M
w100000 or more, the viscosity average molecular weight Mv is
The Staudinger index was determined and calculated by the method. However, in Example 1, the weight average molecular weight Mw (BASF method:
GPC).

The numerical value of the variation coefficient B of the torque coefficient of the above equation (6), which indicates the degree of stabilization of the fastening body tightening force of the present invention, was obtained by a test under the following conditions.

Tightening test conditions Standard screw fastener: Nominal diameter hexagon bolt (M16 pitch 2m
m), hexagon nut (both sides taken) M16 pitch 2mm Bolt strength classification: 8.8 Nut strength classification: 8 Use of flat washer: Use of flat washer (HRC40 ± 5) Surface treatment of screw fastener: Zinc plating chromate treatment (JI
SH8610 Class 1 B, Class 3: Chromate treatment) Tightening axial force: 80 KN (however, excluding Table 7, FIGS. 1 to 3, 6, and 7) In the tightening test, a fastener and a measuring device are installed. After the room temperature reached the set ambient temperature during the tightening operation, the temperature was maintained for one hour or more before starting.

As an active ingredient of the stabilizer, a polymer of isobutene (isobutylene), that is, polyisobutylene is trade name “Glissop” manufactured by BASF.
al "and trade name" Oppanol "are commercially available,
In this example, among these, "Glissopa"
l "and" Oppanol ".

As the active ingredient of the stabilizer, a polymer of isobutene and n-butene, that is, polybutene, trade names “Tetrax”, “Hymol”, “Evertac” manufactured by Nippon Petrochemical Co., Ltd. "," Nisseki Polybutene "," SV-7000 ", trade name" VISTANEX "manufactured by Exxon, trade name" Idemitsu Polybutene "manufactured by Idemitsu Petrochemical Co., Ltd., trade name manufactured by NOF Corporation “Polyvis” and a product name “In” manufactured by Amoco
dopol ”and“ Napvis ”(trade name, manufactured by BP) are commercially available. In this example,“ Tetrax ”and“ Idemitsu Polybutene ”were used.

A mixed composition of the above polyisobutene and the above polybutene was used.

As the tightening force stabilizer of the product of the present invention, an isobutene polymer, an n-butene polymer, a copolymer of isobutene and n-butene, or a mixture of two or more thereof can be used. In the case of a mixture, those having various viscosities can be prepared (details are described in the margins of Tables 2 and 3). Table 2 (Examples 1 to 12) shows the case where polybutene was adhered without dissolving in an organic solvent to form a film, and Table 3 (Examples 13 to 27) shows that polybutene was machine oil (ISO VG46). ) Is used (Compatibility ratio is described in Table 3).

Mineral oil (machine oil), which is a lubricant used in Comparative Example 1, is commonly used for screw tightening, "IS
OVG46 ", and a lubricant containing a calcium compound-based solid lubricant (Solbest 103: manufactured by STT) was used as the paste containing the solid lubricant of Comparative Example 2. In addition, a Torukar CHA Green (manufactured by Nippon Oil & Fats Co., Ltd.) Torukar-treated product was used as the water-soluble resin dry-coated product as the stabilizer of Comparative Example 3, and the epoxy resin (Epicoat 828) was used in Comparative Example 4. : Yuka Shell Epoxy Co., Ltd.).

According to the above conditions and settings, the tightening force stabilizing characteristics (coefficient of variation B of torque coefficient) of the fastening body as a result of the tightening test using the conventional lubricant and stabilizer are shown below. Table 1 and Table 2 and Table 3 below show the tightening force stabilizing characteristics (coefficient of variation B of the torque coefficient) of the fastening body as a result of the tightening test when the tightening force stabilizer of the present invention was used. Further, the “mixed” state in Tables 2 and 3 indicates a compatible state.

[0057]

[Table 1]

[0058]

[Table 2]

[0059]

[Table 3]

As can be seen from Tables 1 to 3, Comparative Examples 1 to 3 show that the coefficient of variation B of the torque coefficient (hereinafter simply referred to as “variation coefficient B”) exceeds 0.06, Examples of the product of the present invention in which the coalesced particles were adhered to bolts or the like (see Table 2) have a low coefficient of variation B of less than 0.06, a stabilized viscosity of 338 mPa · s or more, or an average molecular weight of 4
In the case of 00 or more, the coefficient of variation B is less than 0.04, and particularly in the case of the stabilized viscosity of 628 mPa · s or more, or the average molecular weight is 570 or more, the extremely excellent stabilization of the coefficient of variation B of less than 0.02 is obtained. The test confirmed that the variation was small.

The coefficient of variation B of the example of the product of the present invention (see Table 3) in which the butene polymer was made compatible with mineral oil and adhered to bolts or the like was found to increase with increasing the butene polymer blending ratio. When the mixing ratio is 10% by mass or more, the coefficient of variation B is less than 0.04, and especially when the mixing ratio is 30% by mass.
When the content is equal to or more than the mass%, it was confirmed that the coefficient of variation B was less than 0.03, and extremely excellent stabilization was obtained, and the variation was small.

Test Example 1 In order to confirm the cause of the above measurement results, the condition of the washer seat surface of the fastening member was observed with an electron microscope, and the results are shown in FIGS.

The state shown in FIGS. 1 to 3 shows a state where it is tightened and loosened.

That is, the electron micrograph of FIG. 1 shows a washer seat surface when a stabilizer having the same composition as in Example 38 was applied and dried, and then tightened with a fastening body tightening axial force of 60 KN. Is an electron micrograph showing the washer seat surface when the lubricant (machine oil) of Comparative Example 5 is applied and tightened with an axial force of 60 KN. FIG. 3 is a paste containing a solid lubricant of Comparative Example 7 (calcium compound solid lubricant). Paste)
5 is an electron micrograph showing a washer seat surface when tightening is performed at an axial force of 60 KN after the application of.

As can be seen from these electron micrographs, the washer seat surface of the tightened body which was tightened after applying mineral oil (machine oil) had a chromium layer (black portion) on the plating surface as shown in FIG. It is partially lost, and it is presumed that galling has occurred.

Further, as shown in FIG. 3, a linear scratch was observed on the entire surface of the washer seat of the fastener after the paste containing the solid lubricant of Comparative Example 7 was applied, and a hard solid was observed. It is presumed that the lubricant is a trace of being rubbed.

On the other hand, in the example of the present invention to which the tightening stabilizer is adhered, the tightened washer seat surface is partially strongly rubbed as shown in FIG. It is clearly observed that a large amount of the compound (see black portion) remains.

Therefore, from these electron micrographs, it can be seen that the tightening force stabilizing agent used in the product of the present invention has superior tightening force stabilizing characteristics as compared with the lubricant etc. of the comparative example.

Test Example 2 FIG. 4 is a graph showing the relationship between the viscosity of polybutene as the tightening force stabilizer of the example and the torque coefficient.

It can be seen that the logarithm of the viscosity and the torque coefficient are substantially linear in the viscosity range of 2000 mPa · s or more. If the viscosity is 235 mPa · s or more, as can be seen from Table 3 shown above, the desired stabilizer having practically sufficient excellent performance and small variation can be obtained as compared with the conventional example, It can be seen that by adjusting the viscosity, the advantage that a desired torque coefficient can be set can be obtained. Furthermore, as can be seen from Table 2,
It can be seen that when the viscosity is in the range of 630 mPa · s or more, the advantage that a stabilizer having a very small variation in the variation coefficient B can be obtained can be obtained.

Test Example 3 FIG. 5 shows a case where the tightening force stabilizer of Example 1 was used, and FIG.
9 is a graph showing the results of examining the effect of the environmental temperature during the tightening operation on the torque coefficient when using machine oil as the lubricant of Comparative Example 1.

Regarding the tightening force stabilizer of Example 1,
It can be seen that the torque coefficient has a very small dependency on the tightening temperature, whereas the torque coefficient of the lubricant machine oil of Comparative Example 1 changes significantly.

In the screw tightening work, when controlling the fastening body tightening axial force of the fastening body with the tightening torque, it has not been almost considered the influence of the temperature, but the work is performed outdoors such as a construction site. If this is the case, the ambient temperature during the tightening operation usually changes greatly. In such a case, the fact that the dependence of the variation coefficient B of the torque coefficient on the tightening temperature is small contributes greatly to the stabilization of the tightening axial force because the tightening axial force is managed by the torque method.

Test Example 4 FIG. 6 shows a case where the tightening force stabilizer of Example 38 was used.
When the machine oil of Comparative Example 5 was used, when the paste containing the calcium compound-based substance of Comparative Example 7 was used, and when the paste containing the molybdenum disulfide-based solid lubricant was used, the results of repeated tightening characteristics were tested. It is a graph shown. The ambient temperature during the fastening operation is 24 ° C.

Depending on the fastening body, the tightening and loosening may be repeated many times. At this time, if the torque coefficient decreases, overtightening occurs. Conversely, if the torque coefficient increases, the tightening force becomes insufficient, which may lead to a serious accident. Absent.

As can be seen from FIG. 6, when the machine oil of Comparative Example 5 and the paste containing the solid lubricant of Comparative Example 7 are used after ten times of repetitive tightening, the torque coefficient is greatly reduced as the repetitive tightening is performed. I understand. In this case, if the number of tightening increases, overtightening tends to occur, and an excessive force is applied to the fastener.

On the other hand, in the case of Example 7 using the stabilizer of the present invention, it was found that the change in torque coefficient hardly occurred, and there was an advantage that the problem of the above conventional example was not caused. can get.

Test Example 5 FIG. 7 is a graph showing the results of a comparison test of the loosening characteristics between the case where the tightening force stabilizer of Example 7 was used and the case where the lubricant machine oil of Comparative Example 1 was used. It is.

As can be seen from the results of this comparative test, when a lubricant machine oil was used, a certain tightening axial force (5
5 to 60 KN), the tightening axial force gradually decreases gradually when the tightening force stabilizer of Example 7 of the present invention is used.

Such a phenomenon occurring in the product of the present invention is a very advantageous point also from the damage-tolerant design concept used for an aircraft, for example. In other words, damage-tolerant design is based on the premise that defects (damage) exist from the beginning, and through repeated inspections during operation, these damages must be discovered before they grow to a critical size, and appropriate repairs made. The purpose of this is to maintain the soundness of the structure, and even if the screw fastener becomes loose, it is extremely superior to the conventional example in that it will not easily reach a fatal looseness until the next inspection. Thus, in applications where safety is extremely important, the advantages and importance of applying the product of the present invention are enormous.

Next, the results of a test confirming the effect of deposits (water, oil) on the surface of the fastener on the stabilizing effect of the tightening force stabilizer of the example will be shown.

That is, when the fastening force stabilizer is attached to the surface of the fastening member component such as a bolt, if water or oil is attached to the surface, the torque coefficient due to the attachment of the fastening force stabilizer is reduced. We examined whether it would adversely affect stabilization. Needless to say, this effect is preferably small. The results are shown in Table 4. The degree of adhesion of water and oil was such that the entire bolt and nut were immersed in water or oil, and the stabilizer was adhered to such an extent that water or oil did not drip.

[0083]

[Table 4]

As can be seen from the results, even if water or oil adheres to the surface of the fastening member component, the stabilizer of the present invention has a small coefficient of variation B of 0.02 It was confirmed to be within an extremely excellent numerical range of less than.

Test Example 6 Further, a stabilizing agent was dissolved in an organic solvent, and was applied to the surface of a fastening member component such as a bolt by a method such as coating, and then dried. Was conducted, and the results are shown in Table 5 below (only this test example was dissolved in an organic solvent).

[0086]

[Table 5]

As can be seen from the results shown in Table 5, when the product of the present invention containing a butene polymer as an active ingredient is used, fastening components such as bolts and the like due to differences in the degree of polymerization (ie, differences in average molecular weight). The properties of the adhesion layer formed on the surface of
Although it was different from a rubbery, liquid, or soft viscous material, it was confirmed that in any case, the coefficient of variation B was extremely stable with less than 0.02.

Test Example 7 Table 6 shows the results of examining the effect of surface treatment on the fastening body. Surface treatment is zinc plating chromate treatment is JIS
H8610 Class 1 B, Class 3 was used, and the dacrotization treatment was performed by coating zinc particles and a chromium compound.

[0089]

[Table 6]

As can be seen from the results in Table 6, it was confirmed that the coefficient of variation B was extremely stable.

Test Example 8 The results of examining the effect of the tightening axial force on the fastening body are shown in Table 7.
It was shown to.

[0092]

[Table 7]

As can be seen from the results shown in Table 7, it was confirmed that the coefficient of variation B was extremely stable even when the fastening axial force was changed.

[0094]

According to the present invention, the following effects are obtained by the stabilizing agent for the fastening body fastening force, the method for stabilizing the fastening body fastening force, and the fastening body to which the fastening force stabilizer is adhered.

Effect 1) The variation of the coefficient of variation B of the torque coefficient is extremely small, and the tightening axial force when the tightening torque is constant can be stably secured in a range where the variation is extremely small.

Effect 2) The cost is lower than that of a conventional paste containing a solid lubricant.

Effect 3) There is an advantage that the torque coefficient and the variation coefficient B can be set in a target range by changing the viscosity.

Effect 4) The coefficient of variation B due to a change in the environmental temperature during the tightening operation is small.

Effect 5) Sudden loosening is unlikely to occur.

Effect 6) It is difficult to peel off (compared to the solid coating type).

Effect 7) Even in repeated tightening and loosening of the fastener, the tightening force is stable.

Effect 8) No special device is required for attaching to the fastener. Therefore, it is hard to be limited by the number of processes and the processing place.

Effect 9) It is hard to be affected by the film thickness seen in the coating type.

Effect 10) It is hardly affected by the adhesion of water or oil to the fastening body.

Effect 11) It is possible to easily cope with a small number of adhesion treatments to the fastening body.

[Brief description of the drawings]

FIG. 1 is an electron micrograph showing a state of a washer seat after a butene polymer as a tightening force stabilizer of Example 38 is applied, tightened and loosened.

FIG. 2 is an electron micrograph showing the state of a washer seat surface tightened and loosened after applying a lubricant (machine oil) of Comparative Example 5.

FIG. 3 is an electron micrograph showing a washer seat surface that has been tightened and loosened after applying the lubricant of Comparative Example 7 (a paste containing a calcium compound-based solid lubricant).

FIG. 4 is a graph showing the relationship between the viscosity of the butene polymer of the tightening force stabilizer of Test Example 2 and the torque coefficient.

FIG. 5 is a graph showing the influence of the environmental temperature during the tightening operation on the torque coefficient for the butene polymer of the tightening force stabilizer of Example 1 and the mineral oil of the comparative lubricant.

FIG. 6 is a graph showing the repetitive tightening characteristics of a paste containing a machine lubricant, a calcium compound-based and a molybdenum disulfide-based solid lubricant as a lubricant compared with a butene polymer as a tightening force stabilizer of Example 38.

FIG. 7 is a graph comparing the loosening characteristics of a butene polymer as a tightening force stabilizer of Example 7 and a machine oil as a comparative lubricant.

FIG. 8 is a graph showing the relationship between bolt elongation and tightening axial force.

FIG. 9 is a graph showing an influence of a change in a torque coefficient on a tightening torque and a tightening axial force.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) // C10N 30:00 C10N 30:00 Z 40:00 40:00 G (72) Inventor Hiroshi Tsuji Tokyo 2-12-12 Omorikita, Ota-ku, Japan Tono Manufacturing Co., Ltd. (72) Inventor Naohiro Ishida 3-13-10, Nishigaoka, Kita-ku, Tokyo Tokyo Metropolitan Industrial Technology Research Institute (72) Inventor Kazuhiro Okubo Tokyo 3-13-10 Nishigaoka, Tohoku-ku Tokyo Metropolitan Industrial Technology Research Institute F term (reference) 3C038 AA01 AA06 EA01 4H104 CA04C CA05C DA02A LA20 PA38 4J002 AE05W BB17X BB18X GH01 HA05

Claims (11)

[Claims] 1. A fastener tightening force stabilizer comprising a polymer of an unsaturated chain hydrocarbon having 4 carbon atoms as an active ingredient of the stabilizer. 2. The polymer of an unsaturated chain hydrocarbon having 4 carbon atoms is a polymer of n-butene, a polymer of isobutene, or a polymer of n-butene.
2. The fastener fastening force stabilizer according to claim 1, which is any one of a copolymer of butene and isobutene, or a mixture thereof. 3. 3. The fastener tightening force stabilizer according to claim 1, wherein the active ingredient of the stabilizer is compatible with 10% by mass or more of the mineral oil. 4. The fastener tightening force stabilizer according to claim 1, wherein an active ingredient of the stabilizer is dissolved in an organic solvent. 5. The method according to claim 1, wherein the active ingredient is ASTM D2503.
The stabilizer for fastening force of a fastener according to claim 1 or 2, wherein the number average molecular weight measured at -92 is 5,000 or less. 6. The method according to claim 1, wherein the active ingredient is an NPCC method (GPC).
3. The fastener tightening force stabilizer according to claim 1, wherein the weight-average molecular weight measured by the method is not less than 50,000. 7. The stabilizer according to claim 1, wherein the viscosity of the stabilizer is 235 mPa · s or more at an ambient temperature during the fastening operation of the fastener. 8. A screw member such as a bolt member and a nut member and a screwed portion of a member to be fastened, and at least one of a screw member such as a bolt member and a nut member, a washer and a seat surface of the member to be fastened. A method of stabilizing a fastening body fastening force, wherein the method comprises attaching the stabilizer according to any one of claims 1 to 7 to use. 9. The fastening force stabilizer according to claim 1, which is previously attached to at least one of a threaded part, a washer, a threaded portion of a fastened body, or a seating surface. A fastener constituting part of the fastener characterized by being stored. 10. A film formed by dissolving and attaching an active ingredient of the stabilizer according to any one of claims 1 to 3 or 5 to 7 in an organic solvent and then volatilizing the organic solvent. The fastener component according to claim 9, wherein: 11. A fastening member having a fastening force stabilizing agent according to any one of claims 1 to 7 attached to a surface thereof is a screw member such as a bolt member or a nut member, or a washer and a member to be fastened. The fastener component according to claim 9 or 10, wherein the fastener component is at least one of them.