Lamination construction method to improve RTRP pipeline construction quality

Abstract

The invention relates to a lamination construction method for improving the construction quality of RTRP pipelines. After the RTRP pipelines are cut and the interfaces are polished, the pipelines are fixed on an operating platform using a binding belt. Fillers are uniformly filled into all gaps of the interfaces of the RTRP pipelines fixed on the operating platform using a scraper and compacted; then the interface layer, the primary layer, the slope layer, the structural layer and the surface layer of the RTRP pipeline are wrapped with a tape in sequence, and finally the RTRP pipeline accessories are constructed and the RTRP pipeline is inspected and tested. The method of the invention has high interface strength, no leakage and flexible installation.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline assembly, and in particular to a RTRP pipeline lamination construction method. Background Art

[0002] In the chemical industry, water supply and drainage and other industries, composite material RTRP (REINFORCED THERMOSETTINGRESIN PIPING)-Reinforced thermosetting resin pipe has occupied a considerable market. This material is made of resin, glass fiber, and quartz sand as raw materials, and is solidified by winding or centrifugal casting. It has attracted more and more attention from the market for its superior cost performance, excellent corrosion resistance, light weight, high specific strength, low friction, superior hydraulic characteristics, strong designability, strong anti-aging, good wear resistance and toughness. It is widely used in municipal water supply and drainage, heating, irrigation, construction, petroleum, chemical industry, light industry, energy, transportation, sewage treatment and other fields, especially in large and medium-sized water supply, sewage discharge, seawater desalination and some industrial transportation pipelines in the Middle East. Different types of resin pipes are almost all used. The pipe connection methods of this material mainly include butt connection, socket-type adhesive connection, flange connection and socket-type sealing ring connection. In the traditional construction method, due to the influence of factors such as environment, materials, equipment, and operator proficiency, a large number of leakage points often appear during the pressure test process or operation process, which brings great losses to the construction unit or production unit. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a lamination construction method for improving the construction quality of RTRP pipelines, so as to achieve the purpose of high interface strength and no leakage.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A lamination construction method for improving the construction quality of RTRP pipelines, the steps are as follows:

[0006] Step 1: RTRP pipe cutting and interface grinding;

[0007] Step 2: RTRP pipeline assembly: Use binding tape to fix the pipeline on the operating platform;

[0008] Step 3: Filler configuration and filling: After the filler configuration is completed, use a scraper to evenly fill the configured filler into all gaps of the RTRP pipe interface that has been fixed on the operating platform and compact it;

[0009] Step 4: Tape wrapping on the opposite layer of the RTRP pipeline; first, apply a layer of adhesive evenly on the surface of the pipeline, and then manually wrap a layer of tape, alternating continuously until all four layers of tape wrapping on the opposite layer are completed;

[0010] Step 5: Wrap the RTRP pipeline with the first layer of tape; use a polishing machine to polish the dried interface layer and corners, clean the powder and pollution, use the tape to start the interface lamination and wrapping construction, apply a layer of adhesive, wrap a layer of tape, and alternately wrap the tape twice, and finally finish and compact it;

[0011] Step 6: Tape wrapping of the slope layer of the RTRP pipeline; after the initial layer of the RTRP pipeline is completed and the joints are checked to be tight and correct, the slope layer tape wrapping construction is started using the wrapping tape; the adhesive brushing and the wrapping tape wrapping are carried out alternately, and finally the finishing is compacted;

[0012] Step 7: RTRP pipe structure layer wrapping tape; first wrap 13 layers of 360 / 100 glass fiber roving cloth on the basis of the groove layer, then wrap 4 layers of 580 / 100 glass fiber roving cloth, and finally wrap 2 layers of 360 / 100 glass fiber roving cloth to finish; adhesive brushing and wrapping are carried out alternately, and finally the structure layer is wrapped with 19 layers of tape manually;

[0013] Step 8: wrapping the RTRP pipe with a surface tape; after the structural layer is wrapped, the adhesive and surface gauze prepared in step 7 are used to wrap the surface layer;

[0014] Step nine: RTRP pipeline accessories construction and RTRP pipeline inspection and testing.

[0015] Furthermore, in step one, when polishing the interface, use a polishing machine to polish off all the wax layers on the surface of the 125 mm width parts of the pipe joint, polish the exposed internal structural layer into a rough surface, and then polish the two pipe ends 1 cm each into a smooth transition groove. Finally, use a blower to clean up all the fiberglass powder and other debris on the inside and the polished surface, and all the joint surfaces will expose the new sand layer of the original RTRP pipe. After the polishing and cleaning of both sides of the butt pipe section is completed, use a hot air blower to heat it. The assembly and lamination process must be completed within two hours after the polishing is completed.

[0016] Furthermore, in step three, the raw materials of the filler include 246g of vinyl resin, 38g of silica powder and 4g of LPT catalyst, and the above raw materials are mixed in proportion in a stirrer and stirred thoroughly to obtain the filler.

[0017] Furthermore, in step 4, step 5 and step 6, the adhesive is prepared by adding 9 g of LPT catalyst to 575 g of ethylene resin.

[0018] Furthermore, in step 4 and step 5, the wrapping tape is made of 270 / 100 glass fiber roving cloth.

[0019] Furthermore, in step six, the wrapping tape is made of 360 / 100 glass fiber roving cloth, and the number of layers wound is 17 in total.

[0020] Furthermore, in step seven, the adhesive is prepared by weighing 1828 g of vinyl resin, 30 g of LPT catalyst, 9 g of retarder and 162 g of UV curing agent, mixing them in a stirrer and stirring them thoroughly.

[0021] Furthermore, in step eight, when winding, start from the middle of the joint of the pipe section to one side, and then to the other side. After winding one layer, scrape off the cotton yarn layer in the gauze, leaving only the silk thread, and continue to wind 3-5 times, and cut it to finish.

[0022] The RTRP pipeline butt joint lamination construction process provided by the present invention has high butt joint tape interface strength, no leakage, and flexible installation. Its reliable construction process can meet the RTRP pipeline construction technical requirements such as new construction, expansion, especially old plant reconstruction involving multiple new and old device connection points. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the tooling and fixing of the RTRP pipeline assembly;

[0024] Figure 2 This is a schematic diagram of the lamination construction of the opposite layers of the RTRP pipeline;

[0025] Figure 3 This is a schematic diagram of the initial lamination construction of the RTRP pipeline;

[0026] Figure 4 It is a schematic diagram of the lamination construction of the RTRP pipeline structure layer.

[0027] In the figure, 1-construction ground, 2-operating platform, 3-wooden triangular wedge, 4-nylon binding belt, 5-RTRP pipe, 6-group groove, 7-wrapping belt. DETAILED DESCRIPTION

[0028] The present invention relates to a lamination construction process for improving the construction quality of RTRP pipelines, which is specifically as follows:

[0029] Construction preparation → Pipe material numbering and cutting → Bevel grinding → Pipe assembly → Pipe fixing → Pipe cleaning → Putty preparation → Putty filling → Interface drying → Putty surface grinding → Tape wrapping and laying of interface layer → Adhesive rolling → Tape wrapping and laying of primary layer → Slope layer wrapping and laying → Adhesive rolling → Structural layer wrapping and laying → Adhesive rolling → Surface layer laying → Rolling and finishing → Air drying → Hardness testing → Water pressure test → Completion acceptance.

[0030] The following is an example of the RTRP pipeline project involved in the SADAF EOP project undertaken by the applicant to illustrate this lamination construction method for improving the construction quality of RTRP pipelines. The RTRP pipelines in this project include different pipe diameters such as D25-DN300. The connection methods of the pipes and pipe fittings of different diameters are all connected by winding and laminating with glass fiber roving. The thickness of the pipe tape and the thickness of the adhesive applied are different for pipes of different diameters. In the Middle East regions such as Saudi Arabia, where the temperature is high, the humidity is high, and the salinity is high in the desert area, the lamination method of winding can ensure that all interfaces are tightly connected. The resin, catalyst and other auxiliary materials and glass fiber roving that are basically the same as those used in the production of RTRP pipelines are continuously polished, wound, solidified and heated to ensure the strength and process performance of the docking interface. Especially in the local underground pipeline network and technical transformation projects, the construction is more convenient and flexible, and it is widely used.

[0031] 1. Preparation for RTRP pipeline construction

[0032] In order to speed up the construction progress, the construction of thermosetting resin pipelines is divided into two parts: prefabrication in the prefabrication yard and on-site installation. When marking the welds on the single-line diagram, the prefabrication ports should be marked reasonably and efficiently to reduce the on-site work content as much as possible.

[0033] RTRP pipes, pipe fittings, guard plates, etc. are all finished products. Before prefabrication, carefully check for scratches, damage or defects. If found, mark them immediately and store them separately and stop using the material.

[0034] Resin, catalyst (LPT) (temperature controlled at 20-25°C), silica powder, glass fiber roving cloth wrapping tape, dressing gauze cloth wrapping tape, etc. must be stored in a cool, dry, clean separate work shed and must be isolated from acids, alkalis, heavy metal compounds, etc., especially the catalyst (LPT) must be stored in a separate space because of its strong oxidizing properties. Saudi Arabia Construction has prepared an air-conditioned room to store these auxiliary materials.

[0035] Prepare operating platform (for fixing RTRP pipes), cutting machine, axial flow fan, blower, grinding wheel polishing machine, (with hook) nylon strap, iron roller, heating blanket, hot air blower, putty knife, scissors, sandpaper, stirrer, mixing bucket, hardness tester, platform scale, disposable protective clothing, gas mask, safety shoes and hats, etc.

[0036] (ii) RTRP pipe cutting

[0037] Mark the size of the material on the pipe according to the single-line diagram of the weld annotation, use a white marker or marking tape, and ensure sufficient reserved space when marking the material. Reserve 1.0mm for 1-4 inches and 2.0mm for 10-12 inches. After the data is confirmed to be correct, use a manual cutting machine to accurately cut the material according to the marked lines.

[0038] (III) RTRP pipeline interface polishing

[0039] After the RTRP pipe is cut, use a polisher to polish off the wax layer on the surface of the 125 mm width of the DN300 FRP pipe joint section, and polish the exposed internal structural layer into a rough surface. Then polish the two material ports 1 cm each into a smooth transition groove (make sure there is no breakage or gap). Finally, use a blower to clean all the FRP powder and other debris inside and on the polished surface to ensure the dryness and cleanliness of the joint surface. All joint surfaces must ensure that the new sand layer of the original pipe is exposed (pay special attention to the polishing quality of the bottom area on both sides of the joint pipe section). After the two sides of the joint pipe section are polished and cleaned, use a hot air blower to heat it to ensure that there is no dew. It should be noted here that the next group must complete the lamination joint process within two hours after the polishing is completed. The roughness and cleanliness of the internal and external joint surfaces of the pipe must be confirmed, otherwise it needs to be polished again. Remember, the quality of polishing is the top priority of the quality control of the pipe lamination interface.

[0040] 4. RTRP pipeline pairing

[0041] Prepare the operating platform and tie bands, fix the cut and cleaned RTRP pipe 5 on the operating platform 2, and use the wooden triangular wedge 3 to leave an operating gap between the operating platforms at the middle docking interface. After the joint surface of the butted pipe section is inspected and qualified, start the assembly. The maximum gap between the DN25-DN100 pipe section and the maximum gap between the DN150-DN300 pipe section is 1mm, and the maximum gap between the DN150-DN300 pipe section and the DN25-DN100 pipe section is 2mm. After the pipe is docked, use the nylon tie band 4 to fix it on the operating platform 2. When the pipe section docking operation starts, prevent it from any movement and collision to ensure the stability of the operation.

[0042] (V) Filling configuration and filling

[0043] Prepare a clean and dry mixing barrel. The DN300RTRP pipe filler configuration is configured according to the project volume. Weigh 246g of vinyl resin, 38g of silica powder and 4g of LPT catalyst for each seam, mix and stir in a stirrer for about 3 minutes. Ensure that the mixture is evenly mixed and free of bubbles before use. At the same time, it must be used within half an hour to prevent its deterioration from affecting the quality of the first seam filling construction. After the filler configuration is completed, use a scraper to evenly fill the configured filler into all the gaps of the RTRP pipe interface that has been fixed on the operating platform and compact it. After the gap is filled, the filler should be dried and polymerized. The construction temperature is high and it takes about 2 hours. During this period, it is strictly forbidden to move or impact the filled pipe in any way to affect the connection quality of the interface filler. If the temperature is low, consider heating it with a hot hair dryer or an electric heating blanket. The temperature should be controlled at about 100-110℃ to ensure uniform polymerization and hardening inside and outside the junction.

[0044] RTRP pipe joint layer wrapping

[0045] After the filler is dried, polymerized and inspected, use a grinder to grind off the uneven parts of the filler. At the same time, make sure that all smooth surfaces 50mm on both sides of the joint have been polished to expose the rough surfaces to ensure cleanness and dryness. During this period, use a clean mixing bucket to prepare the adhesive. For each joint, take 575g of ethylene resin and add 9g of LPT catalyst, and stir evenly without bubbles for use. Get 270 / 100 glass fiber roving cloth from the material warehouse and start winding the interface layer. First, use a roller to evenly apply a layer of adhesive on the surface of the cleaned pipe. Immediately, manually wrap a layer of glass fiber roving cloth, and keep alternating. Before wrapping each layer of tape, make sure to apply the adhesive all the way, until the 4 wrappings of the interface layer are all completed manually. Finally, use scissors to cut the tape, and compact it tightly. During construction, pay attention to 50% overlap of the wound glass fiber roving cloth. Each layer should be evenly tightened to avoid wrinkles, missing wraps, and excessive spacing. If the angle is not adjusted well, use scissors to cut part of the side of the tape to adjust the angle.

[0046] (VII) RTRP pipeline primary tape wrapping

[0047] After the construction of the RTRP pipeline joint interface is completed, check again that all smooth surfaces at 125mm on both sides of the interface gap have been polished to reveal the rough surface and ensure that they are clean and dry. At the same time, use a polishing machine to polish the dried interface layer and corners, and clean the powder and pollution again to ensure that the next process can be carried out. Use 270 / 100 glass fiber roving cloth to start the interface lamination glass fiber roving cloth winding construction, apply a layer of adhesive, wrap a layer of glass fiber roving cloth, and alternately wrap the tape twice, and finally finish and compact it.

[0048] 8. RTRP pipeline slope layer wrapping

[0049] After the initial construction of the RTRP pipeline is completed and the joints are checked to be tight, the warehouse picks up 360 / 100 glass fiber untwisted roving cloth to start the slope lamination tape winding construction. This layer is wound with 17 layers in total. Due to the large number of layers, when the adhesive is applied and the roving cloth is wound alternately, each layer must be evenly tightened, and remember not to produce wrinkles, missing winding, too large spacing, etc. For the last few layers, use scissors to cut the side of the tape to adjust the tape angle, and finally finish and compact it.

[0050] (IX) RTRP pipeline structure layer wrapping

[0051] Prepare a clean and dry mixing barrel. The DN300RTRP pipe structure layer adhesive is configured according to the project volume. For each seam, weigh 1828g of vinyl resin, 30g of LPT catalyst, 9g of retarder and 162g of UV curing agent, mix them in a blender and stir them thoroughly for about 3 minutes. Ensure that the mixing is even and there are no bubbles before use. At the same time, check that the joint slope layer is tight and correct. After ensuring cleaning, the material warehouse collects 360 / 100 and 580 / 100 glass fiber roving cloth to start the laminated structure layer winding construction. On the basis of the slope layer, first wrap 13 layers of 360 / 100 glass fiber roving cloth, then wrap 4 layers of 580 / 100 glass fiber roving cloth, and finally wrap 2 layers of 360 / 100 glass fiber roving cloth to finish. During the specific construction, a roller is still used to evenly apply the prepared adhesive on each layer of the structural layer wrapping glass fiber roving, and then the wrapping required by the process is tightly and continuously wrapped, alternating. Before wrapping each layer of tape, the adhesive must be applied all the way, until the 19 wrappings of the structural layer are all completed manually. Finally, the tape is cut with scissors, and the end is pressed and compacted. During construction, the wrapped glass fiber roving is still overlapped by 50%. Each layer must be evenly tightened to avoid wrinkles, missing wraps, and excessive spacing. When the angle is not adjusted well, use scissors to cut part of the side of the tape to adjust the angle of the tape.

[0052] (10) RTRP pipeline surface wrapping

[0053] After the structural layer is wrapped according to the construction requirements, the material warehouse picks up 100mm wide gauze for the surface layer winding construction. The adhesive uses the adhesive configured for the structural layer. The specific construction should start from the middle of the RTR pipe section joint to one side, and then to the other side. The tension must be guaranteed for each circle. After wrapping one layer, scrape off the cotton yarn layer in the gauze, leaving only the silk thread, and then wrap it about 3 times, cut off the end, so that the arc of the final interface surface is smooth.

[0054] RTRP pipeline accessories construction

[0055] The construction of RTRP pipeline accessories mainly includes the construction of flange heads, elbows, tees, bracket guard plates, and pipeline openings of corresponding materials.

[0056] The construction process of RTRP pipe fittings is the same as that of pipelines, and the lamination winding method is also used for the construction of pipe fittings. When constructing flanges, first insert the corresponding caliber slip-on flanges into the pipeline, and then select the corresponding caliber flange heads for construction according to the lamination process of pipeline joints. After the position of the FRP bracket is located for the guard plate construction, the contact surface with the guard plate is polished and cleaned at the same time, and then bonded with the prepared adhesive, and finally tied and fixed with a tie to complete the entire construction process.

[0057] For RTRP pipeline drilling, first locate the hole according to the single-line diagram using a steel ruler and a marker, then select the appropriate wrapping tape according to the size of the hole and cut it into corresponding blocks, then construct from the primary layer to the surface layer according to the construction process of pipeline butt joint lamination, and use an electric drill to drill the hole after drying and polymerization.

[0058] During the construction of the RTRP pipe support guard plate, the smooth surface of the inner surface of the guard plate and the pipe surface is polished away to expose the rough surface, all powder and debris are cleaned up, and after drying and cleaning, it is pasted with the prepared adhesive and fastened with a binding tape.

[0059] 12. RTRP pipeline inspection and testing

[0060] 1. After the pipeline construction is completed, all joints shall be tested for hardness according to the drawings and the requirements of the third-party testing agency.

[0061] 2. For pipelines installed on site, according to the classification of pressure test packages, select 1.5 times the design pressure for strength test and the design pressure for tightness test.

[0062] The present invention adopts low-temperature storage of auxiliary materials such as resin and catalyst, combined application of fixed pipe mouth binding belt and construction platform, application time of prepared materials, precautions of each process and final acceptance of pipe mouth quality, combined with actual cases on site, to provide certain reference significance for efficient and smooth construction of RTRP pipeline, especially RTRP pipeline construction in Saudi Arabia and other Middle East regions.

Claims

1. A lamination construction method for improving the construction quality of RTRP pipelines, characterized in that: Step 1: RTRP pipe material selection, cutting and interface polishing; When grinding the interface, use a polisher to grind off all the wax layers on the surface of the 125 mm wide part of the pipe joint, and grind the exposed internal structural layer into a rough surface. Then grind the ends of the two pipes into a smooth transition groove of 1 cm each. Finally, use a blower to clean all the fiberglass powder and other debris inside and on the grinding surface, and expose the new sand layer of the original RTRP pipe on all joint surfaces. Step 2: RTRP pipeline assembly: Use binding tape to fix the pipeline on the operating platform; Step 3: Filler configuration and filling: After the filler configuration is completed, use a scraper to evenly fill the configured filler into all gaps of the RTRP pipe interface that has been fixed on the operating platform and compact it; The raw materials of the filler include 246g of vinyl resin, 38g of silica powder and 4g of LPT catalyst. The above raw materials are mixed in a stirrer according to proportion and stirred thoroughly to obtain the filler, and the filler is filled into the assembled gaps with a scraper. If the temperature is low, a hot air blower is used to heat it to accelerate the curing process in order to shorten the construction time; Step 4: Tape wrapping on the opposite layer of the RTRP pipeline; first, apply a layer of adhesive evenly on the surface of the pipeline, and then manually wrap a layer of tape, alternating continuously until all four layers of tape wrapping on the opposite layer are completed; Step 5: Wrap the RTRP pipeline with the first layer of tape; use a polishing machine to polish the dried interface layer and corners, clean the powder and pollution, use the tape to start the interface lamination and wrapping construction, apply a layer of adhesive, wrap a layer of tape, and alternately wrap the tape twice, and finally finish and compact it; In step 4 and step 5, the wrapping tape is made of 270 / 100 glass fiber roving cloth; Step 6: RTRP pipeline slope layer wrapping; after the RTRP pipeline initial layer construction is completed and the joints are checked to be tight and correct, the slope layer wrapping construction is started with the wrapping tape; the adhesive brushing and the wrapping tape wrapping are carried out alternately, and finally the end is compacted and compacted; in this step, the wrapping tape is made of 360 / 100 glass fiber untwisted coarse cloth, and the layer is wrapped with 17 layers in total; In step 4, step 5 and step 6, the adhesive is prepared by adding 9g of LPT catalyst to 575g of ethylene resin; Step seven, RTRP pipeline structural layer wrapping tape; first wrap 13 layers of 360 / 100 glass fiber roving cloth on the basis of the groove layer, then wrap 4 layers of 580 / 100 glass fiber roving cloth, and finally wrap 2 layers of 360 / 100 glass fiber roving cloth to finish; the adhesive brushing and wrapping are carried out alternately, and finally until the structural layer is wrapped with 19 layers of tape all manually completed; in this step, the preparation method of the adhesive is: weigh 1828g of vinyl resin, 30g of LPT catalyst, 9g of retarder and 16g of UV curing agent, mix and stir well in a stirrer; Step 8: Wrap the RTRP pipe with a surface tape; after the structural layer is wrapped, use the adhesive prepared in step 7 and the surface gauze to wrap the surface layer; when wrapping, first wrap from the middle of the pipe section joint to one side, and then to the other side. After wrapping one layer, scrape off the cotton yarn layer in the gauze, leaving only the silk thread, and continue to wrap 3-5 times, and cut off the end; Step nine: RTRP pipeline accessories construction and RTRP pipeline inspection and testing.

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