Method and system for coating bolt and nut pairs using molybdenum disulfide dry film lubricant

Abstract

The present invention belongs to the field of coating technology, and specifically to a method and system for coating bolt nuts with molybdenum disulfide dry film lubricant, comprising: pre-treating the surface of the nut, mixing the concentration of the molybdenum disulfide dry film lubricant based on the thickness of the molybdenum disulfide lubricant coating, coating the nut and drying and curing it, performing surface molybdenum disulfide lubricant coating flatness detection and adhesion detection on the dried and cured nut, and making a judgment based on the detection result, wherein nuts that meet the detection standard indicate that the entire coating process has been completed, nuts that do not meet the standard are returned to the coating treatment step for rework, the quality pass rate of the nuts after coating is improved by roughening treatment and setting environmental conditions, the molybdenum disulfide lubricant coating coated on the surface of the nut is tested for flatness and adhesion, unqualified nuts are reworked, and the nut coating method is optimized to meet the long-term use requirements of the nuts.

Description

Technical Field

[0001] The invention belongs to the technical field of anchor rods, and in particular to a method and a system for coating bolt and nut pairs with molybdenum disulfide dry film lubricant. Background Art

[0002] Nuts are fasteners with internal threads that are used in conjunction with bolts. They are universal basic parts with a wide range of uses and are widely used in industrial fields such as transportation, mechanical equipment, etc. With the development of industrial modernization, the requirements for the surface performance of mechanical equipment and parts are becoming higher and higher.

[0003] A patent application with publication number CN107150017A discloses a coating method for nut products, including: pre-treatment of parts such as sandblasting and ultrasonic cleaning as required, placing the treated nuts in a dipping container for dipping with dry film lubricating coating, then placing them in a centrifugal dryer for drying and natural drying, placing the nuts in the dipping container again for dipping and centrifugation and natural drying, placing the products on a pallet for pre-curing and curing after spraying, and delivering the products for inspection.

[0004] In the above-mentioned prior art, the nut products are sprayed, and the thickness, flatness and adhesion of the coating of the nut after spraying are not tested. Whether the nut spraying is qualified is not specifically analyzed, which will cause the nut to fail to meet long-term use requirements.

[0005] To this end, the present invention provides a method and system for coating bolt and nut pairs using molybdenum disulfide dry film lubricant. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0007] The technical solution adopted by the present invention to solve the technical problem is: the method and system for coating bolt nuts with disulfide dry film lubricant of the present invention comprises: step 1: roughening, cleaning and drying the surface of the nut base;

[0008] Step 2: Determine the standard thickness of the molybdenum disulfide lubricant coating to be sprayed on the surface of the nut substrate according to the use requirements, and configure the concentration ratio of the molybdenum disulfide dry film lubricant based on the standard thickness of the molybdenum disulfide lubricant coating;

[0009] Step 3: coating the nut by coating equipment in a specific environment such as ventilation and drying and curing the surface molybdenum disulfide lubricant coating of the coated nut;

[0010] Step 4: Use a thickness measuring instrument to measure the thickness of the molybdenum disulfide lubricant coating in the threaded ring of the nut, obtain thickness points with thickness different from the standard thickness, construct a plane coordinate system, mark the reference points on the Y-axis based on the specific value of the standard thickness of the molybdenum disulfide lubricant coating, mark the thickness points and connect them to form a thickness point connection line;

[0011] By making line processing on the thickness point connection line and calculating and analyzing the area of ​​the enclosed interval, the flatness error coefficient of the molybdenum disulfide lubricant coating in the threaded circle of the nut is obtained, and the flatness of the molybdenum disulfide lubricant coating is detected and determined by the flatness error coefficient, and the nut judged to be unqualified by the detection is subjected to the molybdenum disulfide lubricant coating for completion coating and other treatments;

[0012] Step 5: Scratch and tape the qualified nuts. By analyzing the volume of the adhered coating, the number of scratches and the original volume of the coating on the nut substrate surface, the adhesion coefficient of the molybdenum disulfide lubricant coating is obtained. The adhesion of the molybdenum disulfide lubricant coating is determined by the adhesion coefficient. Nuts that are qualified by the test have completed the entire coating process. Nuts that are unqualified by the test return to the coating step and the process is repeated.

[0013] Roughening methods include: grinding with a grinding wheel, sandblasting, pickling, electrochemical polishing, electric spark machining, etc., which roughen the surface and improve the adhesion of the nut surface to the molybdenum disulfide lubricant coating;

[0014] The cleaning process includes: placing the nut in a cleaning agent, removing dirt and residue on the surface of the nut through vibration and the impact of the cleaning liquid, and drying the cleaned nut to prevent the nut from rusting and reducing the adhesion of the molybdenum disulfide lubricant coating.

[0015] Specific environmental requirements include: coating environment temperature, coating environment relative humidity, coating pressure, and drying temperature.

[0016] The reference point is the starting end of the reference line, the reference line is a straight line parallel to the X-axis, and the length of the reference line is the circumference of the internal thread circle of the nut.

[0017] The Y coordinate of the thickness point is the specific thickness value of the thickness point, and the X coordinate of the thickness point is the total circumference of all single thread turns contained between the thickness point detection position and the starting detection position of the thickness measuring instrument.

[0018] The line processing includes: drawing perpendicular lines from both ends of the thickness point connection line to the reference line and drawing a second perpendicular line to the X-axis through the foot of the perpendicular line.

[0019] The closed interval includes: a closed interval enclosed by the reference line, the second perpendicular line and the X-axis, and a closed interval enclosed by the perpendicular line, the reference line and the thickness point connection line.

[0020] The specific process of obtaining the adhesion coefficient is to mark the volume of the MoS2 lubricant coating as hi;

[0021] Calculate the original volume of the molybdenum disulfide lubricant coating on the surface of the nut substrate and mark it as fi;

[0022] Collect the number of traces and mark them as gi;

[0023] The volume of the molybdenum disulfide lubricant coating taken by the tape, the original volume of the lubricant coating on the nut substrate, and the number of scratches were processed and the formula Obtain the adhesion coefficient, where is the preset correction factor.

[0024] A system for coating bolt and nut pairs with molybdenum disulfide dry film lubricant includes: a pretreatment module for roughening, cleaning and drying the surface of the nut substrate;

[0025] A configuration module is used to adjust the concentration of the molybdenum disulfide dry film lubricant according to the usage requirements;

[0026] A coating module, used for coating the nuts under ventilation and certain environmental conditions and drying and curing the coated nuts;

[0027] The first detection module is used to detect the flatness of the molybdenum disulfide lubricant coating on the surface of the nuts after drying and curing, and determine whether the nuts meet the standards based on the detection results;

[0028] A completion module, used for applying a molybdenum disulfide lubricant coating or performing a grinding process on nuts that are judged to be substandard by the first detection module to meet the qualified standards;

[0029] A second detection module is used to perform surface molybdenum disulfide lubricant coating adhesion detection on the nuts determined to meet the standards by the first detection module, and determine whether the nuts meet the standards based on the detection results;

[0030] The rework module is used to return the nuts that are judged as not meeting the standards by the second detection module to the coating processing step for rework.

[0031] After the nut has been completed and coated with a molybdenum disulfide lubricant coating or polished to meet the qualified standards in the completion module, it will continue to be inspected and judged by the second detection module.

[0032] The beneficial effects of the present invention are as follows:

[0033] 1. The method and system for coating bolt and nut pairs with molybdenum disulfide dry film lubricant of the present invention comprises the following steps: measuring the thickness of the molybdenum disulfide lubricant coating in the threaded ring by a thickness measuring instrument, obtaining thickness points different from the standard thickness, constructing a plane coordinate system, marking reference points on the Y axis based on the specific value of the standard thickness of the molybdenum disulfide lubricant coating, and calculating and obtaining the flatness error coefficient by line processing. The flatness of the molybdenum disulfide lubricant coating is determined by the flatness error coefficient. The scratch treatment and tape adhesion treatment are performed to obtain the molybdenum disulfide lubricant coating adhered by the tape and calculate its volume. The volume of the molybdenum disulfide lubricant coating adhered by the tape, the original volume of the lubricant coating on the nut substrate surface and the number of scratches are processed to obtain the adhesion coefficient. The adhesion of the molybdenum disulfide lubricant coating is determined by the adhesion coefficient. Through the above-mentioned detection and determination of the flatness and adhesion of the molybdenum disulfide lubricant coating, the nut coating method is optimized and the nut coating qualification rate is improved, so that the coated nuts can meet the long-term use requirements.

[0034] 2. The method and system for coating bolt nuts with molybdenum disulfide dry film lubricant described in the present invention first detects and determines the flatness of the molybdenum disulfide lubricant coating, performs supplementary coating and other treatments on nuts that do not meet the standards, further performs surface molybdenum disulfide lubricant coating adhesion detection and determination on nuts that have passed the treatment, reworks and optimizes unqualified nuts until they pass, thereby improving the utilization rate of the nuts while optimizing the coating method. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will be further described below in conjunction with the accompanying drawings.

[0036] Figure 1 is a flow chart of a method according to a first embodiment of the present invention;

[0037] Figure 2 1 is a concentration ratio diagram of the molybdenum disulfide lubricant in Example 1 of the present invention;

[0038] Figure 3 is a line diagram of thickness points;

[0039] Figure 4 It is a flow chart of the system of embodiment 2 of the present invention. DETAILED DESCRIPTION

[0040] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods. Example

[0041] like Figure 1As shown, the method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to an embodiment of the present invention comprises: step 1: roughening, cleaning and drying the surface of the nut base;

[0042] Among them, the roughening methods include: grinding with a grinding wheel, sandblasting, pickling, electrochemical polishing, electric spark machining, etc., to roughen the surface and improve the adhesion of the nut surface to the molybdenum disulfide lubricant coating;

[0043] Put the nut into the cleaning agent, and remove the dirt and residue on the surface of the nut through vibration and the impact of the cleaning liquid. Dry the cleaned nut to prevent the nut from rusting and reduce the adhesion of the molybdenum disulfide lubricant coating;

[0044] Step 2: According to the use requirements, determine the standard thickness of the molybdenum disulfide lubricant coating to be sprayed on the surface of the nut substrate. Based on the standard thickness of the molybdenum disulfide lubricant coating, configure the concentration ratio of the molybdenum disulfide dry film lubricant. The specific molybdenum disulfide lubricant coating thickness corresponding to the molybdenum disulfide lubricant concentration ratio is Figure 2 As shown, the prepared molybdenum disulfide lubricant is placed into the coating equipment;

[0045] Step 3: Coating the nuts with coating equipment in a specific environment such as ventilation and drying and curing the coated nuts;

[0046] Among them, the ventilation environment requirements are: the coating environment temperature is not less than 12°C, the relative humidity of the coating environment is not less than 75%, the coating pressure is 0.1MPa-0.25MPa, and the drying temperature is 90-120°C;

[0047] Step 4: Test the flatness of the molybdenum disulfide lubricant coating on the dried and cured nuts and determine whether the nuts meet the standards based on the test results;

[0048] The method comprises: measuring the thickness of the molybdenum disulfide lubricant coating in the thread ring of the nut after drying, analyzing it with reference to the standard thickness, obtaining the flatness error coefficient of the molybdenum disulfide lubricant coating in the thread, and marking it as pi, judging the flatness of the molybdenum disulfide lubricant coating in the thread based on the flatness error coefficient of the molybdenum disulfide lubricant coating in the thread, and conducting surface molybdenum disulfide lubricant coating adhesion test on the nuts that meet the standards after judgment;

[0049] For nuts that do not meet the standards, the molybdenum disulfide lubricant coating is applied to the reference thickness points or polished to meet the qualified standards. Specifically, based on the standard thickness of the coating, the higher thickness points are polished, and the lower thickness points are applied with the coating to meet the standard thickness of the coating;

[0050] The standard thickness is the thickness of the molybdenum disulfide lubricant coating required to be applied to the surface of the nut substrate according to the use requirements;

[0051] The specific process of obtaining the thickness error coefficient of the molybdenum disulfide coating is as follows: use a thickness measuring instrument to measure the thickness of the molybdenum disulfide lubricant coating in the thread ring, obtain thickness points different from the standard thickness, and mark the thickness points as a1, a2, a3...ai, such as Figure 3 As shown, a plane coordinate system is constructed, a reference point is marked on the Y-axis based on the specific value of the standard thickness of the molybdenum disulfide lubricant coating, and a straight line parallel to the X-axis is made through the reference point as a reference line;

[0052] The reference point is the starting end of the reference line, the length of the reference line is the circumference of the thread circle, and the obtained thickness point is marked in the coordinate system;

[0053] The Y coordinate of the thickness point is the specific thickness value of the thickness point, and the X coordinate of the thickness point is the total circumference of all single thread turns between the thickness point detection position and the starting detection position of the thickness measuring instrument;

[0054] Specifically, for point a1, the thickness detector starts to scan the thread circle from the starting end of the thread circle. When point a1 is detected, the circumference of the scanned thread circle is the X coordinate value of point ai;

[0055] Connect the marked thickness points with straight lines to form a thickness point line, draw perpendicular lines from both ends of the thickness point line to the reference line, calculate the area of ​​the closed interval enclosed by the perpendicular line, the reference line and the thickness point line based on the thickness point coordinates, and mark the area of ​​the closed interval as li;

[0056] Based on the vertical line made above, make a second vertical line to the X-axis through the foot of the vertical line, calculate the area of ​​the closed interval surrounded by the reference line, the second vertical line and the X-axis, and mark the area of ​​the closed interval formed as oi;

[0057] The area li of the closed interval enclosed by the obtained vertical line, the reference line and the connecting line is ratioed to the area oi of the closed interval enclosed by the reference line, the second vertical line and the X-axis (pi=li / oi) to obtain the flatness error coefficient pi of the molybdenum disulfide coating in the thread;

[0058] The flatness of the molybdenum disulfide coating is determined as follows:

[0059] The preset flatness error coefficient pi threshold is p;

[0060] If the flatness error coefficient pi < p, it means that the flatness of the molybdenum disulfide coating of the nut meets the standard, and the next step of analysis is carried out;

[0061] If the flatness error coefficient pi ≥ p, it means that the flatness of the molybdenum disulfide coating of the nut does not meet the standard. For nuts whose flatness does not meet the standard, the molybdenum disulfide lubricant coating is applied to the reference thickness point to meet the qualified standard.

[0062] Step 5: Perform surface molybdenum disulfide lubricant coating adhesion test on nuts whose molybdenum disulfide lubricant coating flatness meets the standard, and make a judgment based on the test results. Among them, nuts that meet the judgment standard indicate that the entire coating process is completed, and nuts that do not meet the judgment standard are returned to the coating processing step for rework;

[0063] Specifically, the molybdenum disulfide lubricant coating on the surface of the nut substrate is scratched, the obtained scratches are subjected to a tape adhesion treatment, the molybdenum disulfide lubricant coating adhered with the tape is obtained and its volume is calculated, and the volume of the adhered molybdenum disulfide lubricant coating is marked as hi;

[0064] Calculate the original volume of the molybdenum disulfide lubricant coating on the surface of the nut substrate and mark it as fi;

[0065] Collect the number of traces and mark them as gi;

[0066] The volume of the molybdenum disulfide lubricant coating taken by the tape, the original volume of the lubricant coating on the nut substrate, and the number of scratches were processed and the formula Obtain the adhesion coefficient, where To preset the correction factor, the adhesion of the molybdenum disulfide lubricant coating is determined by the adhesion coefficient;

[0067] The preset adhesion coefficient threshold is d;

[0068] If the adhesion coefficient di of the molybdenum disulfide lubricant coating is less than the adhesion coefficient threshold d, it means that the adhesion of the molybdenum disulfide lubricant coating does not meet the standard, and the nut is returned to the coating treatment step for rework;

[0069] If the adhesion coefficient di of the molybdenum disulfide lubricant coating ≥ the adhesion coefficient threshold d, it means that the adhesion of the molybdenum disulfide lubricant coating meets the standard, and the nut meets the test standard;

[0070] After passing the above tests, nuts that meet the test standards have completed the entire coating process.

[0071] Embodiment 2

[0072] like Figure 4 As shown, a system for coating bolt and nut pairs with molybdenum disulfide dry film lubricant includes: a pretreatment module for roughening, cleaning and drying the surface of the nut base;

[0073] A configuration module is used to adjust the concentration of the molybdenum disulfide dry film lubricant according to the usage requirements;

[0074] A coating module, used for coating the nuts under ventilation and certain environmental conditions and drying and curing the coated nuts;

[0075] The first detection module is used to detect the flatness of the molybdenum disulfide lubricant coating on the surface of the nuts after drying and curing, and determine whether the nuts meet the standards based on the detection results;

[0076] A completion module, used for applying a molybdenum disulfide lubricant coating or performing a grinding process on nuts that are judged to be substandard by the first detection module to meet the qualified standards;

[0077] A second detection module is used to perform surface molybdenum disulfide lubricant coating adhesion detection on the nuts determined to meet the standards by the first detection module, and determine whether the nuts meet the standards based on the detection results;

[0078] A rework module, used for returning nuts that do not meet the standards as determined by the second inspection module to a coating process step for rework;

[0079] Among them, the nuts that have been completed and coated with a molybdenum disulfide lubricant coating or polished to meet the qualified standards in the completion module continue to be inspected and judged by the second detection module.

[0080] Working principle: first, the surface of the nut base is roughened, cleaned and dried, and the thickness of the molybdenum disulfide lubricant coating required to be sprayed on the surface of the nut base is determined according to the use requirements. Based on the thickness of the molybdenum disulfide lubricant coating, the concentration ratio of the molybdenum disulfide dry film lubricant is configured and the configured molybdenum disulfide lubricant is placed in the coating equipment. The nuts are coated with the coating equipment in a ventilated environment and the coated nuts are dried and cured. Secondly, the surface molybdenum disulfide lubricant coating flatness of the nuts after drying and curing is tested and whether the nuts meet the standards is determined based on the test results. Finally, the surface molybdenum disulfide lubricant coating adhesion test is performed on nuts whose molybdenum disulfide lubricant coating flatness meets the standards, and a judgment is made based on the test results. Among them, nuts that meet the judgment standards indicate that the entire coating process is completed, and nuts that do not meet the judgment standards are returned to the coating process step for rework.

[0081] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for coating bolt and nut pairs using molybdenum disulfide dry film lubricant, characterized in that include: Step 1: Roughen, clean and dry the surface of the nut base; Step 2: According to the use requirements, determine the standard thickness of the molybdenum disulfide lubricant coating to be sprayed on the surface of the nut substrate, and configure the concentration ratio of the molybdenum disulfide dry film lubricant; Step 3: coating the nuts by coating equipment in a ventilated specific environment and drying and curing the molybdenum disulfide lubricant coating on the surface of the coated nuts; Step 4: Use a thickness measuring instrument to measure the thickness of the molybdenum disulfide lubricant coating in the threaded ring of the nut, obtain thickness points with thickness different from the standard thickness, construct a plane coordinate system, mark the reference points on the Y-axis based on the specific value of the standard thickness of the molybdenum disulfide lubricant coating, mark the thickness points and connect them to form a thickness point connection line; By making a line processing on the thickness point connection line and calculating and analyzing the area of ​​the enclosed interval, the flatness error coefficient of the molybdenum disulfide lubricant coating in the threaded circle of the nut is obtained, and the flatness of the molybdenum disulfide lubricant coating is detected and determined by the flatness error coefficient, and the nut judged to be unqualified is subjected to a molybdenum disulfide lubricant coating supplementary coating treatment; Step 5: Scratch and tape the qualified nuts. The adhesion coefficient of the molybdenum disulfide lubricant coating is obtained by analyzing the volume of the adhesive coating, the number of scratches, and the original volume of the coating on the nut substrate surface. The adhesion of the molybdenum disulfide lubricant coating is determined by the adhesion coefficient. The nuts that are qualified by the test represent that the entire coating process has been completed. The nuts that are unqualified by the test return to the coating step to repeat the process; The specific process of obtaining the adhesion coefficient is to mark the volume of the molybdenum disulfide lubricant coating as hi; Calculate the original volume of the molybdenum disulfide lubricant coating on the surface of the nut substrate and mark it as fi; Collect the number of traces and mark them as gi; The volume of the molybdenum disulfide lubricant coating taken by the tape, the original volume of the lubricant coating on the nut substrate, and the number of scratches were processed and the formula Obtain the adhesion coefficient, where is the preset correction factor.

2. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The roughening method includes: grinding with a grinding wheel, sandblasting, pickling, electrochemical polishing, and electric spark machining to roughen the surface and improve the adhesion of the nut surface to the molybdenum disulfide lubricant coating; The cleaning process includes: placing the nut in a cleaning agent, removing dirt and residues on the surface of the nut through vibration and the impact force of the cleaning liquid, and drying the cleaned nut to prevent the nut from rusting and reduce the adhesion of the molybdenum disulfide lubricant coating.

3. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The specific environmental requirements include: coating environment temperature, coating environment relative humidity, coating pressure, and drying temperature.

4. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The reference point is the starting end of the reference line, the reference line is a straight line parallel to the X-axis, and the length of the reference line is the circumference of the internal thread circle of the nut.

5. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The Y coordinate of the thickness point is the specific thickness value of the thickness point, and the X coordinate of the thickness point is the total circumference of all single thread turns contained between the thickness point detection position and the starting detection position of the thickness measuring instrument.

6. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The line drawing process includes: drawing perpendicular lines from both ends of the thickness point connection line to the reference line and drawing a second perpendicular line to the X-axis through the foot of the perpendicular line.

7. The method for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 1, characterized in that: The closed interval includes: a closed interval surrounded by the reference line, the second perpendicular line and the X-axis, and a closed interval surrounded by the perpendicular line, the reference line and the thickness point connection line.

8. A system for coating bolt and nut pairs using molybdenum disulfide dry film lubricant, which implements the method for coating bolt and nut pairs using molybdenum disulfide dry film lubricant according to any one of claims 1 to 7, characterized in that: include: A pretreatment module is used to roughen, clean and dry the surface of the nut substrate; A configuration module is used to adjust the concentration of the molybdenum disulfide dry film lubricant according to the usage requirements; A coating module, used for coating the nuts under ventilation and certain environmental conditions and drying and curing the coated nuts; The first detection module is used to detect the flatness of the molybdenum disulfide lubricant coating on the surface of the nuts after drying and curing, and determine whether the nuts meet the standards based on the detection results; A completion module, used for applying a molybdenum disulfide lubricant coating or performing a grinding process on nuts that are judged to be substandard by the first detection module to meet the qualified standards; A second detection module is used to perform surface molybdenum disulfide lubricant coating adhesion detection on the nuts determined to meet the standards by the first detection module, and determine whether the nuts meet the standards based on the detection results; The rework module is used to return the nuts that are judged as not meeting the standards by the second detection module to the coating processing step for rework.

9. The system for coating bolt and nut pairs with molybdenum disulfide dry film lubricant according to claim 8, characterized in that: The nuts that have been completed and coated with a molybdenum disulfide lubricant coating or polished to meet the qualified standards in the completion module continue to be inspected and determined by the second detection module.

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