Indoor and outdoor heat-shrinkable cable terminations, pumped concrete projects, plastering works
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10(6) KV cross-linked polyethylene insulated cables – Manufacturing of indoor and outdoor heat-shrinkable terminal fittings 1 Scope: This technical standard applies to the manufacturing of indoor and outdoor heat-shrinkable terminal fittings for 10(6) KV cross-linked polyethylene insulated cables in electrical installation projects in general industrial and civil buildings. 2 Construction Preparation 2.1 Requirements for equipment and materials: 2.1.1 The equipment and materials to be used must meet the voltage requirements and design specifications, and must come with proof of product conformity. 2.1.2 Main materials: insulated three-prong gloves, insulated tubes, stress tubes, woven copper wires, filling adhesive, sealing tape, sealing tubes, phase color tubes, and rainproof skirts. Auxiliary materials: terminal blocks, solder, cleaner, sandpaper, white cloth, gasoline, flux. 2.2 Main tools: spray lamp, crimping pliers, steel tape measure, hacksaw, soldering iron, electrician’s knife, needle-nose pliers, screwdriver, large porcelain plate. 2.3 Operating conditions: 2.3.1 There should be a spacious working area, the construction site must be clean, and 220V AC power supply should be available. 2.3.2 The ambient temperature at the work site should be above 0°C and the relative humidity below 70%; construction is strictly prohibited in rainy, foggy, or windy weather. 2.3.3 For work at heights (on utility poles), a platform should be set up, and a tent should be erected above the area where work is being carried out to prevent dust from entering (in outdoor areas). 2.3.4 The transformers, high-voltage switchgear (high-voltage switches), and cables have all been installed, and the cable insulation meets the required standards. 3 Operating procedures: The manufacturer provides the operating procedures, which should be followed. In the absence of process instructions, the following production procedure can be followed. It is required that the peeling and cutting process must be carried out continuously from start to finish in one go, to avoid moisture absorption. 3.1 Process flow: Insulation testing, inspection of individual equipment components, removal of the cable insulation layer → welding of the grounding wire → wrapping, filling, and securing of the three-pronged glove → removal of the copper shielding layer and semiconductive layer → securing of the stress tube → crimping of the terminals → securing of the phase-color sealing tube → acceptance testing after power is applied; securing of the insulation tube, securing of the rainproof skirt → securing of the sealing tube → securing of the phase-color tube → acceptance testing after power is applied. 3.2 Inspection of individual equipment components: Check upon unboxing to ensure that the quantity of items matches what is listed on the packing list, and to verify that there are no any abnormalities in appearance; arrange the items in the order specified in the procedures on a large porcelain plate. 3.3 Insulation resistance testing of cables: Open the ends of the cable, use a 2500V insulation tester; only after the test passes can the process proceed to the next stage. 3.4 Removing the cable sheath (Figure 2-23): Figure 2-23, Figure 2-24, Figure 2-25 3.4.1 Removing the outer sheath: Fix the cable vertically using clamps. Measure 750 mm from the cable end (550 mm for indoor ends), and remove the outer sheath. 3.4.2 Stripping the armor: Measure 30 mm of armor from the break in the outer protective layer, tie it with lead wire, and then strip off the remaining part. 3.4.3 Removing the inner cushion layer: Take a 20 mm section of the cushion layer from the armor fracture, and remove the rest. Then, remove the filler and separate the core wires. 3.5 Welding ground wire (Figure 2-24): Braided copper wire is used for the cable steel strip and shielding to form the ground wire. First, separate the woven wire into three parts, re-weave them to wrap around each phase respectively, and solder them to the shielding copper strip using a soldering iron and solder. Smooth the welded area of the steel strip with sandpaper, then bind it with steel wire and weld it firmly to the steel armor. At the seal, the woven wire is filled with tin to create a moisture-proof section. 3.6 Wrap with filling compound and secure the three-pronged glove (Figure 2-25): 3.6.1 Wrapping with filling compound: Fill and wrap the three-core junction area using cable filling compound. Giving it an olive-shaped appearance. When wrapping the sealing tape, first clean the surface of the cable jacket and the cable core wires. The maximum diameter of the sealing tape when wrapped around the cable should be about 15 mm larger than the outer diameter of the cable, with the ground wire enclosed within it. 3.6.2 Fixing the three-prong glove: Put the glove over the root of the three prongs. Then, heat it with a blowtorch to cause shrinkage and fixation. When heated, it contracts and fixes from the base of the glove toward both ends. 3.6.3 Precautions should be taken when heating and contracting thermoshrinkable materials: 3.6.3.1 The heating and contraction temperature is 110–120°C. 3.6.3.2 Adjust the burner flame to have a soft yellow color; be careful to avoid a high-temperature blue flame, as this can cause burns to the thermally shrinkable materials. 3.6.3.3 When starting to heat the material, the flame should approach it slowly, move around it to ensure even heating, and keep moving in the forward (contracting) direction to preheat the material. 3.6.3.4 The flame should move in a spiral pattern to ensure that the tube contracts evenly in all directions around it. 3.7 Copper shielding layer and semiconductive layer: Measure 55 mm of the copper shielding layer from the tip of the glove, and remove the rest. Measure 20 mm of the semiconductive layer starting from the copper shielding layer, and strip off the rest. 3.8 Create a stress cone. Wipe the cable core clean with alcohol, then proceed according to the requirements in Figure 2-26. Figures 2-26 and 2-27 3.9 Fixed-stress tube: Clean the copper shielding layer, semiconductive layer, and insulating surface using a cleaner to ensure that there are no carbon residues on the surface. Then, the three phases are respectively inserted into the stress tubes, with a 20 mm overlap of the copper shielding layer, and heated and contracted upward starting from the lower end of the stress tubes for fixation. 3.10 Crimp terminals: First determine the length of the wire; add 5 mm to the depth of the terminal hole. Strip the insulation from the wire core, and shape both ends into a \"pencil tip\" shape. For crimp terminals, clean the surface, fill the gaps between the terminal and the insulation as well as the indentations on the terminal with filler, and overlap the insulation and the terminal by 10 mm each to smooth them out. 3.11 Fixed insulating tube: After cleaning the surfaces of the insulating tube, stress tube, and finger cover, insert the insulating tube to the root of the trifurcation (with the upper end of the tube extending 10 mm beyond the filler). Heated and fixed starting from the root. 3.12 Fixed-phase color-sealing tube: Fit the phase-color sealing tube over the terminal connection part, preheat the terminal first, and heat it while securing it from the upper end. The indoor cable terminal has been fabricated. 3.13 Fixed rain skirt (Figure 2-27): 3.13.1 Fixed three-hole rain skirt: Fit the three-hole rain skirt according to the dimensions shown in the figure. Then, heat the neck to secure it. 3.13.2 Fixed single-hole rain skirt. Fit the single-hole rain skirt according to the dimensions shown, and heat it to secure it in place. 3.14 Fixed sealing tube: Fit the sealing tube over the terminal connection part, preheat the terminal first, and then heat and fix it starting from the upper end. 3.15 Fixed-phase color tube: Fit the phase color tubes onto the sealed tubes and heat them to fix them in place. The outdoor head has been completed. 3.16 Power-on operation acceptance: 3.16.1 Testing. After the cable terminations are completed, they are tested by the testing department as required. 3.16.2 Acceptance. After passing the tests, it was powered on and operated under no-load conditions for 24 hours without any abnormalities; thereafter, the acceptance procedures were completed and it was handed over to the construction party for use. At the same time, submit technical documents such as change requests, product manuals, certificates of conformity, test reports, and operation records. 4 Quality Standards 4.1 Assurance Items: 4.1.1 The cable terminations shall be tightly sealed, with adequate filling material, and free from bubbles or cracks ； The core wires are tightly connected. The results of the voltage withstanding test, leakage current, and insulation resistance must meet the requirements specified in the construction specifications. 4.1.2 The semiconductor tape and shielding tape of the cable terminal shall not extend beyond the highest point in the stress cone; the taper should be uniform and the surface smooth. 4.1.3 The cable terminations are installed and secured firmly, with the correct phase sequence. Inspection method: Visual inspection and examination of installation records and test records. 4.2 Basic requirements: The cable connector should have an attractive appearance, be smooth with no wrinkles, and have a glossy finish. Inspection method: Visual inspection. 5 Finished product protection 5.1 After counting the equipment and materials, place them in ceramic dishes in order and cover them with a white cloth to prevent foreign objects from getting in. 5.2 Once the cable terminal is prepared, notify the testing department to conduct the tests as soon as possible. After passing the test, install and fix it. It is then connected to the transformer and high-voltage switch, and put into operation to supply power. When power supply cannot be restored temporarily or other operations are underway, the cable ends must be protected to prevent them from being damaged by impact or collision. 6 Quality issues to note 6.1 From the start of peeling and cutting to completion, the process must be carried out continuously in one go to avoid moisture absorption. 6.2 Quality issues to be noted during the cable termination process (Table 2-8). Quality issues to be paid attention to during cable terminal fabrication Table 2-8 Sequence Number Common quality issues Preventive and corrective measures 1 Excessive leakage current during testing 2 When cleaning the insulating surface of the core wire, use insulated gloves; avoid heating to such an extent that local burning or loss of luster occurs – adjust the heating flame to a yellow color. The heating flame cannot remain in one place. Bubbles appear when the heat-shrink tube contracts due to heating; it is necessary to rotate it in a certain direction while continuing to apply heat for contraction. Cracks occur when the end of the insulating tube contracts due to heating; the end face must be smooth when cutting the insulating tube. 7 Quality records that should be kept: 7.1 Product certification. 7.2 Equipment and material inspection records. 7.3 Cable test report form. 7.4 Self-inspection records. 7.5 Records of design change discussions. This post was last edited by 3721 on 2007-3-11 11:31]
Technical Instructions Card for Pumped Concrete Engineering 1. Pre-construction preparations 1.1 Positioning, installation and commissioning of the pumping machine at the site. 1.2 Additional preparation for pump hoses and chuck gaskets. 2. Key points of the construction process 2.1 Before pouring the concrete, send someone to water the formwork until it is thoroughly moist. Recheck the correctness of the formwork and rebar installation, and set up the concrete pump pipe. 2.1.1 Before pumping concrete, the pump operator must thoroughly check whether the pump’s power supply, electrical circuits, oil systems, oil pipes, and other components are safe and functional, and then start the pump for a no-load test run. 2.1.2 Before pumping concrete, prepare the cement mortar with the same strength grade as that of the concrete to be pumped in advance. Fill the feed hopper with water first, start the pump to flush out the water and moisten the pump pipes, then feed in the cement mortar, and finally pump in the concrete. When pumping concrete, pay attention to maintaining the amount of material remaining in the hopper; it is strictly prohibited to allow the flow to stop due to an empty hopper. 2.1.3 When pumping concrete, attention should be paid to its slump (which should generally be kept between 12 and 16 mm). In cases of high temperatures, the pump pipes should be covered with sacks and soaked with water to keep them moist, thereby preventing the concrete from losing moisture, drying out, and hardening during transport, which could cause blockages in the pipes. 2.1.4 During the pumping of concrete, if a \"pipe blockage\" occurs, the pump operator should immediately reverse the pump to perform suction. If suction three times is ineffective, the section of the pipe that is blocked should be identified immediately; the pump should be stopped, the blocked pipe removed, a new pipe installed, and concrete pumping resumed, with the concrete inside the blocked pipe being cleaned up afterward. 2.2 Ensure the concrete mix is evenly distributed; in areas where it is difficult to reach, manual handling is used to spread the mix. It is strictly prohibited to use vibration rods to flatten the concrete mix. 2.3 Carefully limit the blanking height, and reserve blanking and vibration ports at an appropriate height. 2.4 Pouring should be carried out in layers; concentrated pouring is strictly prohibited. The order of pouring and tamping is from far to near, and from low to high. It is strictly forbidden to pour near the supports to prevent the pump pipes’ pulsations from toppling the supports. 2.5 Reinforce the formwork in advance to ensure the safety of the formwork support. 2.6 Strengthen the management of all aspects related to concrete; adding water on site is strictly prohibited. The remaining concrete must not be mixed into the newly poured concrete, ensuring that the variation in slump remains within 2 cm. 2.7 Retarders can be added to prolong the initial setting time and ensure good quality of concrete samples. 2.8 When pouring concrete, set up pump pipe supports and lay temporary walkways to prevent the rebar from shifting due to foot traffic. 2.9 The aggregates and slump of the pumped concrete shall be determined based on the pump pipe diameter, design drawings, and number of construction layers. When pumping ready-mixed concrete, the slump of each truckload should be measured to check whether it meets the specified requirements. 2.10 After the concrete pouring is completed or when pouring is stopped midway, the pump pipe should be cleaned promptly to remove debris and water; such waste material must not be directed at the formwork of columns, beams, and slabs, to prevent the accumulation of sand and debris at the bottom of these elements or at construction joints, which could lead to quality issues with the concrete. 3. Safety regulations 3.1 Due to the high pressure on the pumping feet, they should be placed firmly; each foot should have a cushioning area of 0.3 m2. 3.2 The pump truck should be leveled, and the leg cylinders should be adjusted and locked to prevent the truck from shifting. 3.3 When the fabric rod is in operation, the wind force should be less than level 8; otherwise, operation must be stopped. 3.4 The lowest position of the material rod on the pump truck should be above the mixing shaft; otherwise, air vortices may blow concrete out of the material hopper and cause injury. 3.5 When using air washing for the fabric rod, the rubber hose at its end must be removed and a shut-off plate installed; no one should stand near the end of the hose to prevent injury from concrete residues. 3.6 When there is pressure in the pipeline, its joints must not be disassembled; otherwise, the fluid should first be pumped back. 3.7 Pipes under high pressure at the high-level outlet are prone to wear and may experience pipe explosions; therefore, they should be inspected regularly. Generally, when replacing them with new pipes, these new pipes should be installed first at the pump outlet. 4. In cases not specified in this card, the relevant construction specifications and JGJ59-99 \"Safety Inspection Standards for Building Construction\" shall be followed. 5. Special requirements for this project:
Plastering work construction 1.1 This technical standard applies to plastering works on the interior walls and ceilings of industrial and civil buildings. 2.1 Material requirements: 2.1.1 Gypsum, putty, talcum powder, polyvinyl acetate emulsion, carboxymethyl cellulose, 107 glue, or various types of wallpaper, adhesives, etc. 2.1.2 Wallpapers: To ensure the quality of wall covering, the quality of various wallpapers and wall coverings must meet the design requirements and relevant **standards**. 2.1.3 Adhesives, sealant putties, glass mesh sheets, etc., should be prepared in advance according to the design requirements and the actual needs of the substrate. However, the adhesive must meet the fire safety requirements of the building, to prevent fires from occurring due to the adhesive losing its adhesion at high temperatures and causing the wallpaper to fall off. 2.2 Main Equipment ； 2.2.1 Paper cutting workbench, steel ruler (1m long), wallpaper knife, towel, plastic bucket, plastic basin, putty knife, putty mixing tray, small roller, cutter, brush, squeegee, cloth made of cotton fibers, powder line reel, white thread, iron level, line holder, plumb bob, tape measure, nails, hammer, red pencil, sandpaper. Brooms, tool bags, etc. 2.3 Working conditions: 2.3.1 The concrete and wall plastering have been completed and have dried, with a moisture content of no more than 8% ； Wood products shall not exceed 12%. 2.3.2 Water, electricity, equipment, and the pre-installed components in the ceiling have been completed. 2.3.3 Painting of doors and windows is complete. 2.3.4 Rooms with terrazzo floors have undergone polishing and waxing, and the surface terrazzo has been properly protected. 2.3.5 The walls must be cleaned thoroughly; any unevenness, missing corners, or damaged surface areas should be repaired in advance and allowed to dry. The surface of precast concrete should be leveled using gypsum putty beforehand. 2.3.6 Remove and store in advance any equipment components that protrude from the wall, and reinstall them once the wallpaper has been applied. 2.3.7 If there is a large color difference in the substrate, and thin wallpaper that is prone to showing through is chosen for use, the substrate should be pre-treated before installation to ensure uniform color. 2.3.8 In rooms with high humidity and on wall surfaces that are frequently damp, waterproof wallpaper and adhesives should be used if wall covering is to be applied. 2.3.9 If the room is tall, scaffolding should be prepared in advance; if the room is not tall, wooden stools should be nailed in place in advance. 2.3.10 When providing technical instructions to construction personnel, emphasis should be placed on technical measures and quality requirements. Before carrying out large-scale construction, a sample unit should be built first; only after it is approved by the quality inspection department can the work be assigned to the construction teams. 3.1 Process flow: In principle, the ceiling is covered first, followed by the walls. Base preparation → Leveling, framing, marking lines → Calculating material needs and cutting paper → Applying wallpaper → Trimming the wallpaper. 3.2 Applying wallpaper to ceilings: 3.2.1 Base preparation: Clean the concrete ceiling surface and apply putty evenly. First, remove any dust, debris, or stains from the concrete surface, then sweep away the dust with a broom, followed by applying a layer of putty evenly. The volume ratio of the putty is 1 part polyvinyl acetate emulsion, 5 parts gypsum or talcum powder, and 3.5 parts of a 2% carboxymethyl cellulose solution. After the putty dries, use sandpaper to smooth it; apply a second layer of putty, and once that dries as well, use sandpaper to level and polish it. 3.2.2 Leveling, setting square, marking guidelines, and drawing lines: First, the symmetrical center line of the top piece should be determined by means of leveling, setting square, and marking guidelines, so as to enable symmetric control from the center outward. Principles for handling wall junctions: Follow the mirror-hanging line where one exists; if no such line is available, draw lines according to the design requirements. 3.2.3 Calculating material requirements and cutting paper: Determine the direction in which the wallpaper will be applied based on the design requirements, and then calculate the material needs and cut the paper accordingly. Leave a margin of 2–3 cm on each side according to the measured dimensions. If plastic wallpaper is used, soak it in water for 2–3 minutes, then take it out, shake off the excess water, and dry the surface with a clean towel. 3.2.4 Applying glue and pasting paper: Apply glue to the back of the paper as well as to the areas where it will be attached to the ceiling. It is important to apply the glue in lines corresponding to the width of the wallpaper; the application should not be too wide. When installing the wallpaper, start from the center and work your way toward the edges. For the first sheet, it must be aligned along the already drawn line and glued firmly; care should be taken to leave 1–2 cm of space on each side of the paper so that it is not compressed, in order to meet the requirements for proper alignment when bonding it with the second sheet. Then, follow the same method to apply the second sheet; the two sheets should overlap by 1–2 cm. Use a steel ruler to align them, with two people pressing the ruler in place while one person uses a paper cutter to make the cut. Immediately after that, remove the overlapping parts of the two sheets, and use a squeegee to press the adhesive firmly into the gap. Next, align and straighten the inner corners at both ends of the top piece using a steel ruler, compact it with a scraper and rollers, and finally wipe away the glue marks left on the joint areas by rolling them with a damp towel; repeat this process step by step. 3.2.5 Finishing: After the wallpaper has been applied, it is necessary to check whether there are any areas that are not firmly attached, whether the joints are smooth, whether there is any warping, whether the glue marks have been wiped away, whether there are any bulges, whether the surface is flat, and whether any excess glue has been removed – all until the requirements are met. 3.3 Wallpaper on textured walls: 3.3.1 Substrate preparation: For concrete walls, depending on the quality of the existing substrate, apply 1–2 layers of gypsum putty onto the cleaned wall; once dry, sand it smooth and polish it ； For plastered walls, apply 1 to 2 coats of plain putty to level and smooth the surface, but be careful not to damage the plaster layer ； For gypsum board walls, seal the gaps tightly with joint compound, attach glass mesh fabric or silk strips, satin strips, etc., and then apply compound locally to level the surface. 3.3.2 Checking verticality, using a square, setting out lines: First, the interior and exterior corners of the room must be checked for verticality and alignment using a square; then it is determined which interior corner should be used as the starting point for marking lines according to the dimensions of the wallpaper (*the conventional practice is to start laying the first piece of wallpaper at the left interior corner upon entering the room). If there is a line for hanging the mirror, follow that line; if no such line exists, use string lines as specified in the design. 3.3.3 Calculating materials and cutting paper: Increase the measured wall height by approximately 2–3 cm, and use this dimension to calculate the required materials and cut the paper. The cutting should generally be done on a workbench; after cutting, the paper should be wiped with a damp, warm towel and then folded for later use. 3.3.4 Applying glue and pasting paper: Glue should be applied to both the paper and the wall, and the width of the glue application should match on both surfaces; the glue applied to the wall should not be too wide in a single application. When applying the paper, start by laying the first sheet at the inner corner of the wall; align it using the vertical lines that have been marked, then smooth it out from top to bottom by hand. Use a trowel to press it firmly in place, and apply a small roller to compress the areas at the upper and lower inner corners. Stick the first sheet with a 1–2 cm overhang (about 2 cm beyond the corner), then stick the second sheet on top; press it flat using the same method, ensuring that there is a 1–2 cm overlap with the first sheet. The seams should be aligned from top to bottom, and the pattern should be neat. Use a scraper to level the surface, and use a steel ruler to cut along the overlap between the first and second sheets. Tear off the edges of the paper, press the edges together so that glue is applied, and wipe away any excess glue promptly with a damp cloth. Then, use the same method to cut and tidy up the edges where the sheets meet at the top and bottom, pressing them together with glue. When there are switches or socket boxes on the wall, paper should be cut at those locations as a marker. When pasting, joint seams are not allowed at right angles; at corners, the paper must be cut to create overlapping seams – it is not permissible to lay the paper in one continuous piece to avoid bulging and wrinkles. 3.3.5 Pattern paper assembly: 3.3.5.1 The patterns at the seams of the paper should be aligned and fitted together properly. 3.3.5.2 Before laying, care should be taken to ensure that the pattern and color of the paper are consistent. 3.3.5.3 The overlap of wall and ceiling wallpaper shall be determined according to design requirements; in rooms with a mirror line, the mirror line shall serve as the boundary, while in rooms without such a line, guiding lines shall be used as a reference. 3.3.5.4 When encountering difficulties in achieving a floral pattern joint, any misalignments should be placed in less noticeable recessed corners; the main surfaces should not show any misalignments or chaotic patterns. 3.3.6 Wallpaper finishing: After applying the wallpaper, it should be carefully inspected. Any issues such as curled edges, bubbles, wrinkles, or residual glue marks must be addressed and corrected promptly to ensure the wallpaper is in good condition. 3.7 Construction in winter: 3.4.1 Construction in winter shall be carried out under heated conditions, with the indoor operating temperature not falling below 5°C. 3.4.2 Seal the gaps around doors and windows properly, and assign a dedicated person to monitor temperature, remove moisture, and ensure proper ventilation, in order to prevent cold air from entering and damaging the finished products. 4.1 Guarantee items: 4.1.1 The types, grades, properties, specifications, and patterns of the surface materials and auxiliary materials must meet the requirements of the design documents, product technical standards, and current construction acceptance specifications, as well as the relevant fire safety regulations for interior decoration in buildings. Inspection method: Check the product certificate and on-site material acceptance records. 4.1.2 Wallpapers and wall coverings must be firmly bonded, without any defects such as bulging, warping, or wrinkles. Inspection method: Visual inspection. 4.2 Basic project: 4.2.1 The surface is smooth, without any ripples or unevenness. Wallpaper, wall coverings are in close contact with the mirror mounting lines, faceplates, and baseboards, with no gaps ； Uniform color, without stains; no adhesive marks from strabismus, nor obvious indentations. Inspection method: Visual inspection. 4.2.2 Each panel should be aligned horizontally and vertically, with proper patterns; the patterns at the joints should match. When viewed from 1 meter away from the wall, no seams should be visible. At recessed corners, the panels should overlap in such a way that light passes through smoothly, while at protruding corners there should be no seams, and the angles should be precise with clean edges without any burrs. Inspection method: Visual inspection. 4.2.3 The joints between the plastering compound and the mirror mounting lines, face plates, baseboards, electrical junction boxes, etc., shall be tight with no gaps, no missing or additional applications of material. Any movable parts that do not need to be covered with plastering compound shall have their edges, as well as the edges of the mirror mounting lines, face plates, baseboards, etc., cut neatly and smoothly, without any rough edges. Inspection method: Visual inspection. 4.2.4 Fiberglass wallpaper, non-woven fabric, and satin wall coverings should have a smooth and firm surface, with correct pattern alignment, complete patterns that are symmetrical, no color differences or glue marks, no floating of the surface layer, and straight warp and weft lines. Inspection method: Visual inspection. 5.1 Rooms with wallpaper applied should be cleaned promptly; they must not be used as storage areas or rest rooms to prevent contamination and damage. 5.2 Throughout the entire wallpapering process, it is strictly prohibited for unauthorized personnel to touch the wallpaper. 5.3 When installing electrical and other equipment, care should be taken to protect the wallpaper from contamination and damage. 5.4 When applying wallpaper, it is necessary to follow the procedures strictly. The work must be carried out neatly and efficiently; the edges should be cut properly, and any glue residues must be removed promptly. 5.5 It is strictly prohibited to drill holes in ceilings and walls that already have wallpaper applied. If it is purely a design change, corresponding measures should also be taken; careful protection is required during construction, and thorough repairs must be carried out promptly after construction to ensure the integrity of the wallpaper. 5.6 When applying the second repair oil/paste, cleaning the grinding stone again, and waxing, be sure to protect the wallpaper to prevent contamination, damage from collisions, and other harm. 6.1 Edge warping: This is mainly caused by insufficient application of glue at the joints, partial lack of gluing, or inadequate compaction of the edge seams; as a result, warping of the edges and seams occurs after drying. Once detected, the rubber roller should be promptly coated with glue and pressed to make the repair. 6.2 Lack of paper at the top and bottom ends: This is mainly due to incorrect measurement of dimensions during paper cutting, or the cutter moving while the steel ruler is pressing down on it, resulting in the paper being cut too small. Care and attention must be paid during construction operations. 6.3 Unclean walls with glue marks from misalignment: This is mainly due to the failure to wipe away the glue marks promptly with a damp, warm towel; or insufficient and careless cleaning; or contamination of the surface material caused by other processing steps. 6.4 The wallpaper surface is uneven with bumps: This is mainly due to incomplete cleaning of the underlying wall surface, or cleaning that was not thorough enough; as a result, there is still dust, putty residues, cement stains, small sand particles, and glue lumps on the surface. Hence, bumps appear after the wallpaper is applied ； Or, due to unripe quicklime particles present in the plaster mortar, the wallpaper may also bulge into small bumps. When handling it, cut the wallpaper to remove the dirt, then apply glue again and reattach it properly. 6.5 Bubbles on wallpaper: This is mainly due to a high moisture content in the underlying layer; the wallpaper is applied before the plaster layer has dried. As the plaster layer prevents excess water from escaping, vaporization causes the wallpaper to bulge and form bubbles. During processing, the bubble can be punctured with a syringe and glue can be injected, followed by compression with a roller. 6.6 Bulging of wallpaper at right and left corners, as well as cracks at these corners: At right angles, the wallpaper is usually applied as a whole sheet, and it is necessary to ensure that both surfaces and the corner are properly sized, have a smooth surface, and be firmly attached – which presents certain challenges. The situation at left angles is slightly better, but it is directly related to the quality of the plaster base; ensuring that the adhesive is applied evenly and that proper pressure is applied can help prevent bulging. To prevent cracks at corners, it is essential that the overlap of wallpaper at those corners extend 1–2 cm beyond the corner itself; this creates an additional layer at the actual corner, which prevents the wallpaper from cracking over time due to shrinkage. 6.7 The colors of the surface layer vary, and the intensity of the patterns differs: this is mainly due to poor quality of the wallpaper and inadequate selection during installation. 6.8 The surfaces above and below the window sills, as well as those above and below the curtain boxes, are rough, have poor joint alignment, and are severely contaminated ； It’s mainly due to careless operation. Work responsibility should be strengthened; high standards and strict requirements must be applied, and construction must be carried out carefully in accordance with the regulations. 6.9 In rooms with high humidity and walls that are frequently damp, waterproof wallpaper and adhesives should be used; in rooms subject to acidic corrosion, acid-resistant wallpaper and adhesives should be employed. 6.10 For glass fiber cloth and non-woven wall coverings, they should not be soaked before pasting; simply wipe them with a damp towel and set them aside. This process standard shall include the following quality records: 7.1 Certificates of conformity for materials such as wallpaper. 7.2 Quality inspection and evaluation form for this sub-item of work.