High pressure pipe seal face grinding method

Abstract

The application relates to the technical field of sealing surface grinding, in particular to a high-pressure pipeline sealing surface grinding method, which comprises the following steps: acquiring a first pipeline shape parameter; processing a grinding contact surface through a grinding tool based on the first pipeline shape parameter, so that the processed grinding contact surface is coupled with a pipeline sealing surface; placing grinding material on the grinding contact surface of the grinding tool and tightly abutting the grinding material with the pipeline sealing surface for grinding. The high-pressure pipeline sealing surface grinding method provided by the application reduces the local grinding caused by manual grinding in the grinding process, reduces the uneven contact of the sealing surface, reduces the additional cost caused by outsourcing mechanical processing, adopts a light and not easy-to-wear grinding tool, tightly abuts the grinding tool and the pretreatment surface of the pipeline sealing surface, and keeps the relative movement of the grinding tool and the pipeline sealing surface concentric, so that the treatment of the treatment surface defects is completed, and only the grinding material is consumed in the process, and the grinding tool is not damaged.

Description

Technical Field

[0001] This invention relates to the field of surface grinding technology, and more particularly to a method for grinding the sealing surface of a high-pressure pipeline. Background Technology

[0002] Polyolefins are essential basic chemical raw materials, playing a vital role in the national economy. Polyolefin production is also a key indicator of a country's petrochemical development level. Currently, China is vigorously developing a high-end polyolefin industry chain, and the polyolefin market outlook is promising. A large number of polyolefin plants are currently under construction or about to commence construction. The LDPE / EVA plant, as one of the main units, utilizes foreign technology and products in its core high-pressure section's process package, detailed design, equipment, and components. The high-pressure piping system includes four pressure rating systems: PN4000, PN3600, PN1600, and PN500. The PN3600, PN1600, and PN500 systems use flange connections and high-pressure lens gaskets. Flange connections account for over 70% of all connections in the high-pressure system, making their installation quality crucial. The installation quality of the lens gasket sealing surface is key to ensuring the overall system's tightness. Following the standard installation procedure for high-pressure systems, all connections undergo sequential processes including installation tightening, tightness testing, purging, and overall airtightness verification. The connection pairs require multiple disassembly and tightening. Due to repeated tightening, the sealing surfaces of pipes and lens gaskets will inevitably show indentations, wear, and unavoidable sealing defects. Currently, the conventional methods for handling sealing surface defects in high-pressure systems are manual grinding and outsourced processing. Outsourced processing has a shorter cycle, but for the sealing surfaces of pipe sections, mechanical transportation is required, resulting in a long turnaround time. Most pipe sections are prefabricated and irregularly shaped, requiring high standards for the site and equipment for mechanical processing. Irregularly shaped pipes are installed within the structural frame, and once installed, the space is limited, requiring outsourced processing to be dismantled, significantly increasing the workload and difficulty of dismantling, resulting in high construction costs. Manual grinding, on the other hand, only incurs labor costs and is not limited by space, making it relatively cheaper. However, manual grinding is done locally and in sections, which can lead to uneven treatment of the sealing surfaces, compromised quality, and low grinding efficiency. Summary of the Invention

[0003] In view of this, the present invention provides a method for grinding the sealing surface of a high-pressure pipeline to solve the aforementioned technical problem.

[0004] Specifically, the present invention is achieved through the following technical solution:

[0005] This invention provides a method for grinding the sealing surface of a high-pressure pipeline, the method comprising:

[0006] Obtain the first pipe shape parameters, which include the structural shape sub-parameters and sealing surface size sub-parameters of the high-pressure system pipe sealing surface;

[0007] Based on the structural shape sub-parameters and sealing surface size sub-parameters, the grinding contact surface is processed using a grinding tool to couple the processed grinding contact surface with the pipe sealing surface;

[0008] Abrasive material is placed on the abrasive contact surface of the abrasive tool and then tightly fitted to the pipe sealing surface for abrasive grinding.

[0009] In some embodiments, the abrasive material is sandpaper of different grades.

[0010] In some embodiments, abrasive material is placed on the abrasive contact surface of the abrasive tool and abrasive material is tightly fitted against the pipe sealing surface for abrasive grinding, including:

[0011] The pipe sealing surface is ground by using a handheld low-speed power tool to drive a grinding tool.

[0012] In some embodiments, the grinding includes at least one coarse grinding and at least one fine grinding.

[0013] In some embodiments, the grinding tool is provided with a guide at its center to prevent the grinding material from falling off.

[0014] In some embodiments, the grinding tool is provided with a guide at its center to ensure the concentricity of the grinding tool relative to the pipe sealing surface.

[0015] In some embodiments, the pipe sealing surface has a concave structure, and the grinding contact surface of the grinding tool has a convex structure.

[0016] In some embodiments, the diameter of the guide is smaller than the inner diameter of the pipe.

[0017] In some embodiments, the diameter of the guide is 2-5 mm smaller than the inner diameter of the pipe.

[0018] In some embodiments, the guide is detachably mounted on the grinding end of the grinding tool by a screw.

[0019] The technical solution provided by this invention brings at least the following beneficial effects:

[0020] The high-pressure pipeline sealing surface grinding method provided by this invention reduces uneven contact of the sealing surface caused by localized grinding in manual grinding and reduces the additional costs caused by outsourced machining. It uses a lightweight and wear-resistant grinding tool to ensure that the grinding tool and the pre-treated surface of the pipeline sealing surface are in close contact and maintain concentric relative movement, thus completing the treatment of surface defects. In this process, only grinding material is consumed and no damage is caused to the grinding tool. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the high-pressure pipeline sealing surface grinding method provided in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To facilitate understanding of the high-pressure pipeline sealing surface grinding method described in this embodiment, the relevant defects of the prior art will be explained again:

[0026] Existing processing method 1:

[0027] Manual grinding involves using sandpaper of the appropriate grade to manually grind the defective areas in order to eliminate defects on the sealing surface.

[0028] One drawback of the existing processing method:

[0029] The advantages of manual grinding are low cost, convenient construction, and easy operation. However, its disadvantages include low efficiency. Grinding only targets minor defects and is a localized process. For larger defects, localized grinding can easily lead to uneven grinding, failing to ensure good contact between the lens gasket and the pipe sealing surface. This can cause discontinuous sealing surfaces, affecting installation quality and increasing the likelihood of pipe leaks. Manually grinding the entire sealing surface is time-consuming, has a long cycle, low efficiency, and increased costs.

[0030] The second existing processing method is to outsource machining to a factory, using machine tools to process the sealing surfaces of pipes and lens gaskets to eliminate surface defects.

[0031] Defects of the existing processing method two:

[0032] Machining has the advantages of high efficiency, a wide range of defect handling capabilities, and the ability to process the entire sealing surface, resulting in high-quality machining. However, its disadvantages include the need to transport defective components to a machining plant, making it unsuitable for on-site construction. For irregularly shaped pipe sections already installed, not only is pipe removal difficult, but the workload for auxiliary removal increases dramatically, leading to poor on-site feasibility and operability. Furthermore, processing defects in irregularly shaped pipe sections requires modification of the machining equipment and tooling, resulting in high costs.

[0033] Example 1

[0034] Reference Figure 1 As shown in the figure, this embodiment provides a method for grinding the sealing surface of a high-pressure pipeline, the method including steps S100, S200 and S300.

[0035] Step S100: Obtain the first pipe shape parameters, which include the structural shape sub-parameters and sealing surface size sub-parameters of the high-pressure system pipe sealing surface;

[0036] Step S200: Based on the structural shape sub-parameters and sealing surface size sub-parameters, the grinding contact surface is processed using a grinding tool to couple the processed grinding contact surface with the pipe sealing surface;

[0037] Step S300: Place the grinding material on the grinding contact surface of the grinding tool and grind it in close contact with the pipe sealing surface.

[0038] The pipe sealing surface has a concave structure, while the grinding contact surface of the grinding tool has a convex structure.

[0039] In this embodiment, by reducing uneven contact of the sealing surface caused by localized manual grinding and reducing the additional costs caused by outsourced machining during the grinding process, a lightweight and wear-resistant grinding tool is used to ensure that the grinding tool and the pre-treated surface of the pipe sealing surface are in close contact and maintain concentric relative movement, thereby completing the treatment of surface defects. In this process, only grinding material is consumed and no damage is caused to the grinding tool.

[0040] Example 2

[0041] This embodiment is based on Embodiment 1. The abrasive material is sandpaper of different grades. The sandpaper material in this embodiment can be selected according to the material of the pipe to be processed. Furthermore, the sandpaper materials used for coarse grinding and fine grinding are also different. Specifically:

[0042] Dry sandpaper uses synthetic resin as a binder to bond silicon carbide abrasive to latex, and is coated with an antistatic coating to create a high-end product. It boasts advantages such as anti-clogging, antistatic properties, good flexibility, and high abrasion resistance. Multiple grits are available, suitable for sanding metal surfaces, putty, and coatings. Dry sandpaper is generally made from special kraft paper and latex paper, using natural and synthetic resins as binders, and manufactured using an advanced high-static sanding process. This product features high grinding efficiency and is not prone to chip adhesion, making it suitable for dry sanding, such as the initial coarse grinding of pipes.

[0043] Water-resistant sandpaper, also known as wet sandpaper, gets its name from its ability to be used by immersing in water or sanding underwater. It is made by using water-resistant paper or treated water-resistant paper as a base, with paint or resin as a binder to firmly adhere corundum or silicon carbide abrasive particles to the base. It comes in both sheet and roll forms. Based on the abrasive material, it can be classified as: brown corundum sandpaper; white corundum sandpaper; silicon carbide sandpaper; zirconium corundum sandpaper, etc. According to the binder, sandpaper can be divided into: ordinary binder sandpaper and resin binder sandpaper. Wet sandpaper has a finer texture and is suitable for sanding things with fine textures and is also suitable for post-processing. Wet sandpaper has smaller gaps between the abrasive grains, and the abrasive particles produced are also smaller. When used with water, the particles will flow out with the water, so it must be used with water. If wet sandpaper is used for dry sanding, the particles will remain in the gaps between the abrasive grains, making the sandpaper surface shiny and failing to achieve its intended effect. Dry sandpaper is not so troublesome. The gaps between the abrasive grains are larger, and the abrasive particles produced are also larger. During the sanding process, the particles will fall off due to the larger gaps, so it does not need to be used with water and is suitable for fine grinding in pipe grinding.

[0044] Example 3

[0045] This embodiment is based on Embodiment 1, and involves placing abrasive material on the abrasive contact surface of the abrasive tool and abrading it in close contact with the pipe sealing surface, including:

[0046] The grinding process involves using a handheld low-speed power tool to drive a grinding tool to grind the sealing surface of the pipe. Several requirements exist during this process; for example, the power of the grinding machine is a crucial indicator of its performance. Generally, the higher the power of the grinding machine, the better the grinding effect. Therefore, when selecting a grinding machine, the required power range must be determined based on the specific pipe dimensions and grinding needs.

[0047] Secondly, the rotational speed of the grinder is also a key indicator; too high or too low a speed will affect the grinding effect. Therefore, it is necessary to determine the appropriate rotational speed range based on the hardness of the grinding material and the grinding requirements. Generally speaking, the preferred rotational speed range is 1000-1300 rpm.

[0048] Example 4

[0049] This embodiment is based on embodiment 3 and is used to further illustrate the relevant matters of the pipeline during the grinding process, such as that at least one coarse grinding and one fine grinding should be performed during the grinding process.

[0050] However, existing electromechanical parts have certain drawbacks in processing. Traditionally, electromechanical parts are processed by mechanical grinding. Since the surface thickness of electromechanical parts varies, it is difficult to control the thickness during grinding, which easily leads to uneven surfaces and causes inconvenience in use.

[0051] The specific steps are as follows:

[0052] For cleaning related parts, first clean the electromechanical components by immersing them in a cleaning solution at a temperature of 30-40℃. Wipe the surface of the components with a cotton cloth for 5-8 minutes. After washing, dry the components and let them sit in a ventilated area for 30 minutes to obtain clean parts. Next, perform rough and fine sanding. First, sand the cleaned components with 120-grit sandpaper until evenly coated. Then, use 320-grit dry sandpaper for a second sanding. Rough sanding removes burrs and protrusions around the components, while fine sanding eliminates roughness from the rough sanding process and further refines any defects. Grinding; fine grinding is similar to coarse grinding; if there are still many defects and coarse grinding wheel marks after one pass, grinding should continue; the amount of grinding depends on the number of defects, resulting in the ground electromechanical parts; polishing and cleaning: place the ground electromechanical parts into polishing liquid for polishing, then place the electromechanical parts into the water tank of an ultrasonic cleaner containing deionized water at 40-50℃ for 2-3 minutes. After removal, rinse the parts 2-3 times with clean water, then drain and dry at 60-85℃. Remove and set aside. This completes the high-smoothness grinding method for electromechanical parts, ultimately obtaining electromechanical parts with high gloss.

[0053] After fine sanding, use 480-grit wet sandpaper for final polishing, and finally dry the electromechanical parts at 100-120℃.

[0054] When roughing and fine polishing, polish in the same direction, such as clockwise or counterclockwise.

[0055] Example 5

[0056] This embodiment is based on embodiment 1, and the grinding tool is provided with a guide at the center to prevent the grinding material from falling off.

[0057] Secondly, the guide body can also ensure the concentricity of the relative movement between the grinding tool and the pipe sealing surface.

[0058] Function 1: To counteract radial displacement during mechanical rotation and to act as a guide.

[0059] Function 2: It serves as a fixed grinding material, achieving overall grinding through the relative movement of the grinding tool and the pipe sealing surface, thereby ensuring grinding quality.

[0060] Example 6

[0061] This embodiment is based on embodiment 5 and is used to further illustrate the installation position and dimensional data of the guide body.

[0062] Specifically, the diameter of the guide body is smaller than the inner diameter of the pipe. Preferably, the diameter of the guide body is 2-5 mm smaller than the inner diameter of the pipe. The guide body is detachably mounted on the grinding end of the grinding tool by screws.

[0063] Example 7

[0064] This embodiment provides a high-pressure pipeline sealing surface grinding device, the device comprising:

[0065] The first acquisition module is used to acquire the first pipe shape parameters, which include the structural shape sub-parameters and sealing surface size sub-parameters of the high-pressure system pipe sealing surface.

[0066] The first processing module is used to process the grinding contact surface using a grinding tool based on the structural shape sub-parameters and sealing surface size sub-parameters, so that the processed grinding contact surface is coupled with the pipe sealing surface;

[0067] The second processing module is used to place abrasive material on the abrasive contact surface of the abrasive tool and to fit it tightly against the pipe sealing surface for abrasive grinding.

[0068] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0069] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for grinding the sealing surface of a high-pressure pipeline, characterized in that, The method includes: Obtain the first pipe shape parameters, which include the structural shape sub-parameters and sealing surface size sub-parameters of the high-pressure system pipe sealing surface; Based on the structural shape sub-parameters and sealing surface size sub-parameters, the grinding contact surface is processed using a grinding tool to couple the processed grinding contact surface with the pipe sealing surface; The pipe sealing surface is ground by using a handheld low-speed power tool to drive a grinding tool; the grinding includes at least one coarse grinding and at least one fine grinding. The coarse grinding includes grinding the cleaned electromechanical parts evenly with 120-grit sandpaper, and then grinding them a second time with 320-grit dry sandpaper. The speed of the handheld low-speed power tool is 1000-1300 rpm. The grinding tool is provided with a guide body at its center. The guide body is used to prevent the grinding material from falling off and to ensure the concentricity of the relative movement between the grinding tool and the pipe sealing surface. The diameter of the guide body is 2-5 mm smaller than the inner diameter of the pipe.

2. The high-pressure pipeline sealing surface grinding method according to claim 1, characterized in that, The pipe sealing surface has a concave structure, and the grinding contact surface of the grinding tool has a convex structure.

3. The high-pressure pipeline sealing surface grinding method according to any one of claims 1-2, characterized in that, The guide body is detachably mounted on the grinding end of the grinding tool by screws.

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