A production process for improving the forming quality of a tapered cement pole

Abstract

The application provides a production process for improving the forming quality of a tapered cement pole, and relates to the technical field of cement pole preparation.The production process is characterized by the following steps: numerical control straightening and cutting of steel bars, encryption and reinforcement of ring steel in the tapered section, cleaning of a mold to Ra<=3.2 microns, coating of a water-based release agent and sealing, forced stirring of concrete with a water-cement ratio of 0.32-0.38, layered material distribution and vibration, three-section variable frequency centrifugation with a low speed of 100-200 r / min, a medium speed of 300-500 r / min and a high speed of 600-800 r / min, intelligent tensioning by the post-tensioning method (stress 0.7-0.8 times the ultimate strength), segmented temperature control steam curing (temperature rise <=25°C / h, constant temperature 80+ / -5°C, temperature drop <=20°C / h), natural curing for more than 7 days after demolding, and system inspection of finished products.The application has the following advantages: the steel skeleton precision and the strength of the tapered section can be improved, the appearance and the size precision can be improved, the concrete compactness and the bending resistance can be improved, the centrifugal layering and the internal wall wavy lines can be avoided, the prestress tensioning precision can be improved, the temperature and the dry shrinkage cracks can be reduced, and the product quality is stable and reliable.

Description

Technical Field

[0001] This invention relates to the field of cement pole manufacturing technology, and in particular to a production process for improving the forming quality of tapered cement poles. Background Technology

[0002] Tapered cement poles are widely used supporting components in power transmission and distribution lines, communication and lighting facilities. Their molding quality directly affects the pole's load-bearing capacity, durability, and service life. Currently, the production of tapered cement poles typically includes processes such as steel reinforcement frame fabrication, concrete mixing, concrete placement, mold assembly, centrifugal molding, curing, demolding, and inspection.

[0003] However, in the use of existing technologies, traditional straightening and cutting equipment has a large length error, resulting in eccentricity of the skeleton in the mold and uneven protective layer thickness; the spacing of the ring reinforcement in the conical section is uniform but not reinforced, and the concrete at the small end is easily thrown to the large end during centrifugal molding, causing wall thickness deviation and affecting structural strength; the concrete mix proportion and mixing control are rough, and after centrifugation, stratification and excessive laitance are prone to occur, reducing flexural strength and impermeability; existing centrifuges mostly use fixed speed or simple two-stage speed change, which cannot be precisely controlled according to the flow characteristics of concrete in the conical mold, and problems such as inner wall ripples, uneven wall thickness or insufficient filling at the small end are easy to occur; improper steam curing temperature control, with excessively rapid heating or cooling rates during the preparation process and large temperature differences in the curing kiln, causes internal thermal stress cracking of the concrete; insufficient humidity leads to surface water loss and shrinkage, reducing durability.

[0004] Therefore, there is an urgent need for a production process that can reliably improve the forming quality of cement poles in order to solve the above problems. Summary of the Invention

[0005] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0006] A production process for improving the forming quality of tapered cement poles includes the following steps: Step 1, preparation of steel reinforcement cage: the steel bars are straightened and cut by CNC, and the length accuracy is controlled within ±1mm. Then, the tapered steel reinforcement cage is formed by automatic welding or binding, and the diameter-changing area of ​​the tapered section is set with dense and reinforcing ring bars.

[0007] Step 2, Mold preparation: Clean the inner wall of the lower flat mold to make its surface roughness Ra≤3.2μm, and evenly apply water-based release agent with a coating amount of 0.2 to 0.3 kg / m². After closing the mold, use a 0.1 mm feeler gauge to check the gap between the mating surfaces to ensure that there are no through gaps.

[0008] Step 3, Concrete preparation and mixing: Measure sand, gravel, and cement according to the set mix ratio using electronic metering, control the water-cement ratio to be 0.32 to 0.38, and the slump to be 30 to 50 mm. Use a forced mixer to mix for no less than 120 seconds. After the concrete is discharged from the mixer, check the homogeneity. The density difference of the mortar should be ≤8 kg / m³.

[0009] Step 4, Layered Concrete Pouring and Formwork Closure: Pour concrete into the lower flat formwork in layers, each layer being ≤200mm thick, and use a vibrator to remove air. Then close the formwork and tighten the bolts gradually in three symmetrical steps from the middle to both ends. The final tightening torque is 200-250 N·m for M20 bolts.

[0010] Step 5, Three-stage variable frequency centrifugation: Use a variable frequency speed centrifuge to perform three-stage centrifugation in sequence: low speed, medium speed and high speed. The total time is controlled between 8 and 12 minutes. The speed is 100 to 200 r / min in the low speed stage, 300 to 500 r / min in the medium speed stage and 600 to 800 r / min in the high speed stage.

[0011] Step 6: Post-tensioning of prestressed steel: After centrifugal molding and curing to a certain strength, prestress is applied to the pole. The tensioning stress is controlled at 0.7 to 0.8 times the standard value of the ultimate strength of the steel bar. An intelligent tensioning system is used to monitor the elongation and stress value in real time. The deviation between the measured elongation value and the theoretical value is ≤ ±6%.

[0012] Step 7, Segmented temperature-controlled steam curing: Segmented temperature-controlled steam curing is adopted: heating rate ≤25°C / h, constant temperature stage temperature is 80±5°C and maintained for 4 to 6 hours, constant temperature and humidity ≥95%, cooling rate ≤20°C / h, until the temperature difference with the outside is ≤20°C;

[0013] Step 8, Demolding: When the compressive strength of the test block cured under the same conditions reaches more than 70% of the design value, use a special demolding device to demold it. It is strictly forbidden to knock or pull it.

[0014] Step 9, Natural Curing: Place the demolded pole horizontally on the support, cover it with moisturizing material, spray water 2-3 times a day, and allow it to cure naturally for no less than 7 days. When the ambient temperature is below 5℃, cover it with an insulation blanket and stop spraying water.

[0015] Step 10, Finished Product Inspection: Conduct visual inspection, dimensional inspection, and mechanical performance testing on the poles. The dimensional errors are: length deviation ±5mm, wall thickness deviation ±3mm, and taper deviation ±2mm / m.

[0016] As an improvement, in step 1, the surface of the reinforcing bar after CNC straightening and cutting is free of creases and rust, and the cut end face is flat and free of burrs; the arrangement of the reinforcing ring bars is as follows: at the small end of the tapered pole and in the tapered change area, the spacing of the ring bars is reduced from 200mm to 100mm, or the diameter of the ring bars is increased by 1 to 2mm.

[0017] As an improvement, in step 2, the mold is cleaned using a wire brush or a high-pressure water gun, and then dried with compressed air; if there are pits on the inner wall of the mold, they should be repaired by welding and grinding; after the mold is closed, a light transmission inspection is performed, and no light leakage is acceptable.

[0018] As an improvement, in step 3, the crushed stone has a continuous gradation of 5 to 20 mm in size and a needle-like or flaky content of ≤8%; the sand fineness modulus is 2.6 to 3.0 and the mud content is ≤1.0%; a polycarboxylate-based high-efficiency water-reducing agent is added to the concrete; the mixing sequence is to first add sand, stone, and cement and dry mix for 30 seconds, then add water and admixtures and wet mix for 90 to 120 seconds.

[0019] As an improvement, in step 4, the mold is placed at an angle with the smaller end slightly lower, and the concrete is laid from the larger end to the smaller end; after each layer of concrete is laid, an immersion vibrator is used to vibrate along the mold wall for 10 to 15 seconds; the free fall height of the concrete is ≤500mm.

[0020] As an improvement, the speed deviation of the frequency conversion speed regulation in step 5 is ≤ ±5%; after centrifugal molding, the end plate is disassembled and the inner wall is observed. It should be smooth and free of slurry accumulation; if wavy lines or delamination appear on the inner wall, the running time of the medium or high speed stage is adjusted.

[0021] As an improvement, the intelligent tensioning system in step 6 includes jacks, pressure sensors, displacement sensors, PLC controllers, and data storage modules. It can automatically and synchronously tension, hold loads, and anchor, and draw stress-elongation curves in real time. It will automatically alarm and stop if the deviation exceeds the limit. Tensioning records are generated for each pole and stored for at least 5 years.

[0022] As an improvement, in step 7, steam curing is carried out in a closed curing kiln with a circulating fan installed inside, and the temperature difference within the kiln is ≤5℃. The heating program is as follows: from 20℃ to 45℃ and maintain for 1 hour, from 60℃ to 60℃ and maintain for 1 hour, and from 80℃ to 80℃ and maintain for 1 hour. When cooling down, the kiln door is first opened to slowly dissipate heat, and then the door is fully opened.

[0023] As an improvement, in step 8, when demolding, first loosen the bolts and remove the end plate, then use a hydraulic demolding tool or a gantry crane with special lifting equipment to lift the upper mold smoothly; after demolding, check the surface of the pole, and if there are defects of sticking to the mold, the mold needs to be polished and the release agent adjusted.

[0024] As an improvement, in step 9, the poles are laid flat on sleepers spaced 1.5m apart, with a gap of ≥50mm between poles, and the bottom layer is ≥200mm from the ground; geotextile or plastic film is used as the moisture-retaining material; and the natural curing period for prestressed poles is extended to 14 days.

[0025] The beneficial effects of this invention are as follows: by controlling the length accuracy within ±1mm through CNC straightening and cutting, and by setting up dense and reinforced ring bars in the tapered section diameter change area, the risk of skeleton eccentricity is significantly reduced, the circumferential bearing capacity of the small end and the diameter change area is enhanced, and the wall thickness defects caused by uneven concrete distribution during centrifugal molding are avoided.

[0026] By adopting measures such as surface roughness control, quantitative application of water-based release agent, and gap inspection after mold closing, we can effectively prevent sticking and grout leakage, and ensure that the pole has a smooth appearance and accurate dimensions.

[0027] Employing a three-stage variable frequency centrifugal process with low, medium, and high speeds, the rotation speed and time at each stage are precisely controlled, ensuring that the concrete is evenly distributed and compacted along the conical mold, resulting in a smooth inner wall without delamination or wavy texture.

[0028] The post-tensioning method combined with an intelligent tensioning system controls the tension stress to 0.7 to 0.8 times the ultimate strength, with an elongation deviation of ≤ ±6%. The system automatically records data and issues alarms for exceeding tolerances, which can avoid human error and reduce prestress loss and early cracking. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a production process for improving the forming quality of tapered cement poles according to the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0031] It should be noted that the terms "first" and "second" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0032] like Figure 1As shown, a production process for improving the forming quality of tapered cement poles includes the following steps: Step 1, Reinforcing steel cage preparation: The reinforcing steel is CNC straightened and cut, with the length accuracy controlled within ±1mm. Then, a tapered reinforcing steel cage is formed by automatic welding or binding, and dense reinforcing rings are set in the diameter-changing area of ​​the tapered section; Step 2, Mold preparation: The inner wall of the lower flat mold is cleaned to make its surface roughness Ra≤3.2μm, and a water-based release agent is evenly applied with a coating amount of 0.2 to 0.3kg / m². After the mold is closed, the gap between the mating surfaces is checked with a 0.1mm feeler gauge to ensure that there are no through gaps; Step 3, Concrete preparation and mixing: Sand, gravel, and crushed stone are electronically metered according to the set mix ratio. Stone and cement, with a water-cement ratio controlled at 0.32 to 0.38 and a slump of 30 to 50 mm, are mixed using a forced mixer for at least 120 seconds. After mixing, the homogeneity is checked, and the mortar density difference is ≤8 kg / m³. Step 4, Layered placement and formwork assembly: Concrete is poured into the lower flat mold in layers, each layer ≤200 mm thick, and vented with a vibrator. The mold is then closed, and the bolts are tightened gradually in three symmetrical steps from the middle to both ends. The final tightening torque is 200–250 N·m for M20 bolts. Step 5, Three-stage variable frequency centrifugal molding: A variable frequency speed-controlled centrifuge is used to perform three stages of centrifugal molding: low speed, medium speed, and high speed. The total time is controlled to be 8 to 12 minutes. The rotation speed is as follows: low speed stage: 100-200 r / min; medium speed stage: 300-500 r / min; high speed stage: 600-800 r / min. Step 6: Post-tensioning prestressing: After centrifugal forming and curing to a certain strength, prestress is applied to the pole. The tension stress is controlled at 0.7 to 0.8 times the standard value of the ultimate strength of the steel reinforcement. An intelligent tensioning system is used to monitor elongation and stress values ​​in real time. The deviation between the measured elongation value and the theoretical value is ≤ ±6%. Step 7: Segmented temperature-controlled steam curing: Segmented temperature-controlled steam curing is used: heating rate ≤ 25°C / h; constant temperature stage temperature is 80±5°C and maintained for 4 to 6 hours; constant temperature and humidity ≥ 9%. 5%, cooling rate ≤20°C / h, until the temperature difference with the outside temperature ≤20°C; Step 8, Demolding: When the compressive strength of the test block cured under the same conditions reaches more than 70% of the design value, use a special demolding device to demold it. Knocking or pulling is strictly prohibited; Step 9, Natural Curing: Place the demolded pole horizontally on the support, cover with moisturizing material, spray water 2-3 times daily, and allow natural curing for no less than 7 days. When the ambient temperature is below 5°C, cover with an insulation blanket and stop spraying water; Step 10, Finished Product Inspection: Perform visual inspection, dimensional inspection, and mechanical property testing on the pole. Dimensional errors include: length deviation ±5mm, wall thickness deviation ±3mm, and taper deviation ±2mm / m. During use, the operating data of each device will be centrally transmitted to the central processing module via a wireless signal transmission module and displayed to the administrator via a terminal. It can also be used in conjunction with other terminals to provide timely reminders to operators, effectively ensuring the safe and stable use of the equipment while improving the overall preparation effect.

[0033] In step 1, after CNC straightening and cutting, the surface of the reinforcing bar is free of creases and rust, and the cut end is flat and burr-free. The arrangement of the reinforcing ring bars is as follows: at the small end of the tapered pole and in the tapered change area, the spacing of the ring bars is reduced from 200mm to 100mm, or the diameter of the ring bars is increased by 1 to 2mm. In step 2, the mold is cleaned with a wire brush or high-pressure water gun, and then dried with compressed air. If there are pits on the inner wall of the mold, they should be repaired by welding and grinding. After the mold is closed, a light transmission inspection is performed, and no light leakage is acceptable. In step 3, the crushed stone particle size is 5 to 20mm with continuous gradation, and the content of needle-like and flaky particles is ≤8%; the fineness modulus of sand is 2.6 to 3.0, and the mud content is ≤1.0%; polycarboxylate-based high-efficiency water-reducing agent is added to the concrete; the mixing sequence is to first add sand, stone, and cement and dry mix for 30s, then add water and admixtures and wet mix for 90 to 120s. In step 4, the mold is tilted with the smaller end slightly lower during material placement, and material is placed sequentially from the larger end to the smaller end. After each layer of material is placed, an immersion vibrator is used to vibrate along the mold wall for 10 to 15 seconds. The free fall height of the concrete should be ≤500mm. In step 5, the speed deviation of the frequency conversion speed regulation should be ≤±5%. After centrifugal molding, the end plate is removed to observe the inner wall, which should be smooth and free of laitance accumulation. If wavy lines or delamination appear on the inner wall, the running time of the medium or high speed stage should be adjusted. In step 6, the intelligent tensioning system includes jacks, pressure sensors, displacement sensors, a PLC controller, and a data storage module. It can automatically and synchronously tension, hold loads, and anchor, and draw stress-elongation curves in real time. It automatically alarms and stops when deviations exceed the limit. Tensioning records are generated for each pole and stored for at least 5 years. The recorded information can be transmitted wirelessly to the central processing module, where it is classified, compressed, and stored. Data is retained on locally deployed terminals and in the cloud for easy retrieval later.

[0034] In step 7, steam curing is carried out in a closed curing kiln with a circulating fan. The temperature difference within the kiln is ≤5℃. The heating program is as follows: raise the temperature from 20℃ to 45℃ and maintain it for 1 hour, raise the temperature to 60℃ and maintain it for 1 hour, and raise the temperature to 80℃ and maintain it for 1 hour. When cooling down, first open the kiln door to slowly dissipate heat, and then open the door completely. In step 8, when demolding, first loosen the bolts and remove the end plate, and then use a hydraulic demolding tool or a gantry crane with special lifting equipment to smoothly lift the upper mold. After demolding, check the surface of the pole. If there are defects caused by sticking to the mold, the mold needs to be polished and the release agent adjusted. In step 9, when stacking, the poles are laid flat on sleepers spaced 1.5m apart, with a gap of ≥50mm between poles, and the bottom layer is ≥200mm from the ground. Geotextile or plastic film is used as the moisture-retaining material. The natural curing of prestressed poles is extended to 14 days. In step ten, the visual inspection includes taper, surface smoothness, honeycomb, pitting, and cracks, wherein the total area of ​​honeycomb and pitting is ≤5% of the pole's surface area and the area of ​​a single point is ≤25cm²; the mechanical performance testing includes bending strength, crack resistance, and prestress loss testing, wherein the bending test deflection does not exceed L / 50, the residual deflection is ≤L / 200, and the crack resistance test, when loaded to 120% of the design load, has a crack width ≤0.05mm and a total prestress loss ≤15%; the production process also includes centrifuge equipment maintenance steps: the mold ellipticity is checked every 100 runs, and correction is performed when the deviation is >2mm; the height difference of the centrifuge rollers is ≤1mm.

[0035] Example: A CNC straightening and cutting machine was used to straighten and cut spiral ribbed steel wires with a diameter of 8mm. The length tolerance was set to ±1mm. The actual measured length deviation of each steel bar was between +0.5mm and -0.8mm, and the end face was flat and burr-free. After straightening, the surface of the steel bar was free of creases and rust.

[0036] Construction of the framework: The longitudinal main reinforcement consists of 12 prestressed steel wires with a diameter of 8mm, evenly distributed along the circumference; the circumferential reinforcement uses cold-drawn steel wire with a diameter of 4mm, arranged at 200mm intervals along the entire length of the pole, but at the small end and in areas with tapered changes, the spacing of the circumferential reinforcement is increased to 100mm, and the diameter of the circumferential reinforcement is increased to 5mm. Resistance spot welding is used to weld the circumferential reinforcement to the longitudinal reinforcement to form an integral framework, ensuring strong welds without burning the main reinforcement. Plastic protective layer pads are tied to the outside of the framework in a quincunx pattern at 500mm intervals, with the thickness deviation controlled within ±3mm.

[0037] A segmented, modular conical steel mold (lower flat mold + upper mold) was selected. The inner wall of the mold was cleaned with a high-pressure water gun to remove residual concrete, then polished with a wire brush, and finally dried with compressed air and inspected. Raw materials were then prepared and layered, with a vibrator used to ensure full filling. After centrifugal molding, the inner wall of the pole must be smooth, free of laitance accumulation, and free of ripples.

[0038] After the poles are centrifugally formed, they are left to stand at room temperature for 2 hours before prestressing. The prestressing tendons consist of seven high-strength steel wire bundles with a diameter of 5 mm and an ultimate strength standard value of fptk = 1570 MPa. The tension control stress is taken as 0.75fptk = 1177.5 MPa, corresponding to a tension force of approximately 161.5 kN, given that the area of ​​a single steel wire is 19.6 mm², the total area of ​​the seven wires is 137.2 mm².

[0039] The tensioned poles are placed in a sealed curing kiln equipped with a circulating fan and steam nozzles, maintaining a relative humidity above 95%. Segmented temperature control is employed: Heating stage: from 20℃ to 45℃ (heating rate 25°C / h, 1 hour), to 60℃ (heating rate 15°C / h, 1 hour), and to 80℃ (heating rate 20°C / h, 1 hour). Total heating time is 3 hours, with a maximum heating rate of 25°C / h. Constant temperature stage: 80±2℃, maintained for 5 hours, humidity 96%. Cooling stage: first, steam is shut off, the kiln door is opened slightly (10cm), and the temperature is lowered to 40℃ at a rate of 18°C / h (approximately 2.2 hours), then the door is fully opened for natural cooling until the outdoor temperature difference is ≤20℃. Demolding and natural curing are then carried out. After passing inspection, product identification (specifications, production date, and qualification stamp) is sprayed on the end of the pole, and the poles are stacked according to specifications with wooden strips placed at the bottom, ready for warehousing and shipment.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A production process for improving the forming quality of tapered cement poles, characterized in that, Includes the following steps: Step 1: Preparation of steel reinforcement cage: The steel bars are straightened and cut by CNC, and the length accuracy is controlled within ±1mm. Then, a tapered steel reinforcement cage is made by automatic welding or binding, and dense reinforcing ring bars are set in the diameter-changing area of ​​the tapered section. Step 2, Mold preparation: Clean the inner wall of the lower flat mold to make its surface roughness Ra≤3.2μm, and evenly apply water-based release agent with a coating amount of 0.2 to 0.3 kg / m². After closing the mold, use a 0.1 mm feeler gauge to check the gap between the mating surfaces to ensure that there are no through gaps. Step 3, Concrete preparation and mixing: Measure sand, gravel, and cement according to the set mix ratio using electronic metering, control the water-cement ratio to be 0.32 to 0.38, and the slump to be 30 to 50 mm. Use a forced mixer to mix for no less than 120 seconds. After the concrete is discharged from the mixer, check the homogeneity. The density difference of the mortar should be ≤8 kg / m³. Step 4, Layered Concrete Pouring and Formwork Closure: Pour concrete into the lower flat formwork in layers, each layer being ≤200mm thick, and use a vibrator to remove air. Then close the formwork and tighten the bolts gradually in three symmetrical steps from the middle to both ends. The final tightening torque is 200-250 N·m for M20 bolts. Step 5, Three-stage variable frequency centrifugation: Use a variable frequency speed centrifuge to perform three-stage centrifugation in sequence: low speed, medium speed and high speed. The total time is controlled between 8 and 12 minutes. The speed is 100 to 200 r / min in the low speed stage, 300 to 500 r / min in the medium speed stage and 600 to 800 r / min in the high speed stage. Step 6: Post-tensioning of prestressed steel: After centrifugal molding and curing to a certain strength, prestress is applied to the pole. The tensioning stress is controlled at 0.7 to 0.8 times the standard value of the ultimate strength of the steel bar. An intelligent tensioning system is used to monitor the elongation and stress value in real time. The deviation between the measured elongation value and the theoretical value is ≤ ±6%. Step 7, Segmented temperature-controlled steam curing: Segmented temperature-controlled steam curing is adopted: heating rate ≤25°C / h, constant temperature stage temperature is 80±5°C and maintained for 4 to 6 hours, constant temperature and humidity ≥95%, cooling rate ≤20°C / h, until the temperature difference with the outside is ≤20°C; Step 8, Demolding: When the compressive strength of the test block cured under the same conditions reaches more than 70% of the design value, use a special demolding device to demold it. It is strictly forbidden to knock or pull it. Step 9, Natural Curing: Place the demolded pole horizontally on the support, cover it with moisturizing material, spray water 2-3 times a day, and allow it to cure naturally for no less than 7 days. When the ambient temperature is below 5℃, cover it with an insulation blanket and stop spraying water. Step 10, Finished Product Inspection: Conduct visual inspection, dimensional inspection, and mechanical performance testing on the poles. The dimensional errors are: length deviation ±5mm, wall thickness deviation ±3mm, and taper deviation ±2mm / m.

2. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 1, after CNC straightening and cutting, the surface of the reinforcing bar is free of creases and rust, and the cut end face is flat and free of burrs. The arrangement of the reinforcing ring bars is as follows: at the small end of the tapered pole and in the tapered change area, the spacing of the ring bars is reduced from 200mm to 100mm, or the diameter of the ring bars is increased by 1 to 2mm.

3. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 2, the mold is cleaned using a wire brush or a high-pressure water gun, and then dried with compressed air. If there are pits on the inner wall of the mold, they should be repaired by welding and ground smooth. After the mold is closed, a light transmission inspection is performed, and no light leakage is acceptable.

4. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 3, the crushed stone has a continuous gradation of 5 to 20 mm in size and a needle-like or flaky content of ≤8%; the fineness modulus of the sand is 2.6 to 3.0 and the mud content is ≤1.0%; a polycarboxylate-based high-efficiency water-reducing agent is added to the concrete; the mixing sequence is to first add sand, stone, and cement and dry mix for 30 seconds, then add water and admixtures and wet mix for 90 to 120 seconds.

5. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 4, the mold is placed at an angle with the smaller end slightly lower, and the material is laid from the larger end to the smaller end. After each layer of material is laid, an immersion vibrator is used to vibrate along the mold wall for 10 to 15 seconds. The free fall height of the concrete is ≤500mm.

6. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 5, the speed deviation of the variable frequency speed regulation should be ≤ ±5%; after centrifugal molding, the end plate should be removed and the inner wall should be observed. It should be smooth and free of slurry accumulation. If wavy lines or delamination appear on the inner wall, the running time of the medium or high speed stage should be adjusted.

7. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, The intelligent tensioning system in step 6 includes jacks, pressure sensors, displacement sensors, PLC controllers, and data storage modules. It can automatically and synchronously tension, hold loads, and anchor, and draw stress-elongation curves in real time. It will automatically alarm and stop if the deviation exceeds the limit. Tensioning records are generated for each pole and stored for at least 5 years.

8. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 7, steam curing is carried out in a closed curing kiln with a circulating fan inside. The temperature difference within the kiln is ≤5℃. The heating program is as follows: from 20℃ to 45℃ and maintain for 1 hour, from 60℃ to 60℃ and maintain for 1 hour, and from 80℃ to 80℃ and maintain for 1 hour. When cooling down, the kiln door is first opened to slowly dissipate heat, and then the door is fully opened.

9. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 8, when demolding, first loosen the bolts and remove the end plate, then use a hydraulic demolding tool or a gantry crane with special lifting equipment to lift the upper mold smoothly; after demolding, check the surface of the pole. If there are defects of sticking to the mold, the mold needs to be polished and the release agent adjusted.

10. The production process for improving the forming quality of tapered cement poles according to claim 1, characterized in that, In step 9, the poles are laid flat on sleepers spaced 1.5m apart, with a gap of ≥50mm between poles, and the bottom layer is ≥200mm from the ground; geotextile or plastic film is used as the moisture-retaining material; the natural curing period for prestressed poles is extended to 14 days.

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