A construction process of regeneration gas electric heater

Abstract

The present invention provides a construction process for a regenerative gas electric heater, which includes the following steps in sequence: construction preparation, equipment installation, and electrical instrumentation construction. The present invention is applicable to the installation of main equipment, construction and commissioning of supporting electrical instruments for various types of electric heaters, and can effectively guide construction, improve work efficiency, reduce construction costs, and ensure installation quality.

Description

Technical Field

[0001] The invention relates to the technical field of regeneration gas electric heaters, and in particular to a construction process of a regeneration gas electric heater. Background Art

[0002] Regenerative gas electric heaters have outstanding advantages such as low pollution, high thermal efficiency, safety, and easy control. They are widely used in a wide range of fields, and with the development of energy conservation and environmental protection, their market share is constantly increasing. However, regenerative gas electric heaters are a kind of supporting equipment. The installation work includes professional-related contents such as equipment, electrical and instrumentation, and the installation technology requirements are high. Improper installation will cause the heated materials to deteriorate during operation, and may even cause damage to the heating components, resulting in economic losses.

[0003] For large and high-power models of heater equipment, the installation and debugging technology requirements are high, and in the actual construction process, due to the influence of surrounding conditions, conventional lifting methods cannot be used. Summary of the invention

[0004] In order to solve the above problems, the present invention discloses a construction process for a regenerative gas electric heater, which is suitable for the installation of main equipment, construction and debugging of supporting electrical instruments of various types of electric heaters, and can effectively guide the construction, improve work efficiency, reduce construction costs, and ensure the quality of installation.

[0005] The specific plan is as follows:

[0006] A construction process for a regeneration gas electric heater, characterized in that it comprises the following steps in sequence: construction preparation, equipment installation and electrical instrumentation construction.

[0007] As a further improvement of the present invention, the construction preparation includes equipment unpacking acceptance and equipment foundation acceptance; wherein, the equipment unpacking acceptance includes unpacking acceptance of on-site equipment and its accessories, and unpacking acceptance of distribution panels.

[0008] The equipment unpacking acceptance specifically includes:

[0009] 1) After the heater equipment arrives at the site, unpacking shall be carried out under good weather conditions.

[0010] 2) Before removing the packaging, confirm the appearance and remove the packaging after confirming that it is qualified.

[0011] 3) After removing the box packaging, count the contents according to the packing list and technical agreement:

[0012] 3.1) Check the equipment list, model and take inventory of accessories.

[0013] 3.2) Carry out material testing on special material equipment and accessories according to the technical agreement.

[0014] 3.3) Take inventory of accessories and replacement parts that are not being installed yet, keep video footage and collect them into the warehouse for separate storage.

[0015] The equipment basic acceptance specifically includes:

[0016] 1) Check the basic dimensions and appearance quality as required.

[0017] 2) Confirm the foundation elevation reference line and center position, use fine steel wire to mark the center line position of the horizontal and vertical axes, and then check the related dimensions such as flatness and verticality.

[0018] 3) Before the equipment is put in place, the foundation surface should be trimmed, the foundation surface to be grouting should be chiseled into a rough surface, the oily concrete should be scraped off, and the lower surface of the equipment base should be carefully cleaned to remove rust, oil, etc. At least 6 hours before grouting, the foundation surface and foundation bolt holes to be poured with concrete should be thoroughly wetted, and then the water on the foundation surface and in the bolt holes must be blown dry with compressed air, wiped dry with a rag, or drained with a pump.

[0019] As a further improvement of the present invention, the equipment installation includes equipment positioning and equipment alignment.

[0020] The equipment placement specifically includes: during the equipment installation process, the equipment is located directly below the steel structure, and the upper structure needs to be dismantled when it is hoisted by a crane. In order to reduce the construction cost without dismantling the completed structure, the installation method shown in the figure is adopted; in order to prevent the equipment from falling off during the installation process, a 5t double hoist is used for coordinated traction, and after confirmation by the structural professional, the hoist is fixed on the steel structure directly in front of the equipment foundation for installation; since the equipment body is made of S30408 ​​material, in order to protect the equipment body, a 10t sling is used for pulling during transportation, and the contact position of the equipment is padded; during the sliding process of the equipment, a DN50 thick-walled steel pipe is used as a roller, and a 10mm steel The plate is used for padding. In order to ensure that the equipment does not get stuck during movement due to the sliding of the rollers during sliding, the number of rollers is increased, and personnel are arranged to cooperate synchronously to slide the rollers out of the rear of the equipment base and move them forward again; in order to reduce the longitudinal force when the hoist is pulled, the length of the sliding platform is appropriately increased, and a 10mm steel plate is used on the sandy ground to prevent overturning and collapse during sliding; sleepers are used for support under the sliding platform to ensure that all hardened cement floors are not damaged; after the equipment is transported to the predetermined position on the foundation, a 10t hydraulic jack is used to lift the equipment under the equipment base, the rollers and steel plates are pulled out, and temporary pads are placed on the base for support.

[0021] The equipment alignment specifically includes: the regeneration gas electric heater is the starting point of the process piping of the entire gasoline hydrogenation unit as the raw material preheating equipment. In order to ensure the subsequent pipeline assembly, the accuracy of the equipment position needs to be ensured; during the initial alignment, a precise level is used to carefully level the base in the vertical and horizontal directions, so that the anchor bolts are naturally vertical in the reserved bolt holes, with a spacing greater than 15mm from the hole wall and do not touch the bottom of the hole; during the primary grouting, high-strength non-shrinkage grouting material is used to pour 100mm below and 100mm above the anchor bolt hole. To avoid the formation of bubbles, stir the grouting material; tighten the anchor bolts when the grouting material reaches more than 75% of the design strength. After tightening the nuts, the bolts should protrude 2-3 pitches from the nuts; place a set of formal shims on the left and right of each anchor bolt and on the base beam. After removing the temporary shims, use a frame level to perform secondary alignment of the equipment and perform secondary grouting. The secondary grouting work must be completed in one go with the cooperation of the installers. After the secondary grouting strength reaches the standard, pour C20 concrete into the base to ensure stable operation of the subsequent equipment.

[0022] As a further improvement of the present invention, the electrical instrument construction includes cabinet construction, cable construction, equipment wiring and equipment debugging.

[0023] The cabinet construction includes cabinet hoisting and cabinet installation inspection; among them, cabinet hoisting specifically includes: during the hoisting process, the well-protected cabinet is first hoisted to the reserved hoisting platform on the second floor. Because the inside of the substation is too high, in order to facilitate the tilted cabinet to move inward as much as possible, a movable hoisting device group composed of a hoist and a pulley is used to move it; the cabinet installation inspection specifically includes: according to the "Electrical Installation Engineering Panel, Cabinet and Secondary Circuit Wiring Construction and Acceptance Specification" (GB50171-2012), the cabinet installation is inspected, and the inspection contents are as follows:

[0024] 3.1) Appearance inspection

[0025] Serial number project Permissible deviation 1 Top of two adjacent cabinets ≤2mm 2 Top of the row tray ≤5mm 3 Disk Deviation Adjacent plate edges ≤1mm 4 Column plate ≤5mm 5 Disk seam ≤2mm 6 Verticality (per meter) 1.5mm 7 Exterior paint The cabinet paint surface is intact and undamaged

[0026] 3.2) Component inspection

[0027] The center lines of the moving and static contacts are consistent, and the contacts are in close contact; the switching contacts of the secondary circuit auxiliary switch have accurate movement and reliable contact.

[0028] After checking and confirming the above contents, in order to prevent the welding current from damaging the internal electrical components, the cabinet is fixed by bolt connection (tightening torque 75N.m) and the bolts are marked. After completing the above work, the cabinet body and internal components are grounded and tested for insulation. The grounding resistance is not greater than 1Ω, and the insulation resistance is not less than 1000MΩ.

[0029] As a further improvement of the present invention, the cable construction and equipment wiring include: bridge and piping installation; cable laying and wiring; bridge and piping installation and wiring quality acceptance; cable installation quality acceptance.

[0030] The bridge and piping installation specifically includes:

[0031] 1) The starting point of the heater cable tray is at the C2 substation on the south side of the gasoline hydrogenation unit, and a span is made to connect the internal bridge of the substation. During the connection process, close communication is carried out with the designer to optimize the cable laying line and reduce the number of spans.

[0032] 2) The original design used 32 DN100 galvanized steel pipes as cable protection pipes for laying from the pipe gallery to the equipment. However, considering the small space of the actual construction area on site, the bending radius of the cable protection pipe cannot meet the requirements of the specification. In addition, the cable here is 3×120+1×70mm2 armored cable, and the cable pipe spacing cannot meet the cable heat dissipation requirements. In order to ensure the normal laying of the cable and not affect the normal use of the equipment, the original design laying method was changed to laying in a double-layer cable bridge, which reduced a lot of construction costs and material costs.

[0033] 3) At the equipment wiring buckle, due to the low elevation of the on-site equipment design, the cable bending radius cannot meet the specifications of the specification no matter how it is bent. The protection pipe and bridge at the line inlet are cancelled, and a cable protection pool is added at the heater line inlet. The cable protection pool adopts a brick structure and is filled with coarse sand to protect the cable and ensure the heat dissipation of the cable.

[0034] 4) The instrument cables are laid along the bridge, and the distance from the bridge to the equipment is too long. In order to ensure production safety in the explosion-proof area, the cables originally designed to be laid through pipes are changed to be laid along 50×50mm trough boxes.

[0035] The cable laying and wiring are as follows: the latest linkage cable laying equipment is adopted, which has stable operation, high transmission speed and can be remotely controlled and linked. In cable laying, it is only necessary to set up according to the number of equipment, and each equipment can be equipped with one or two people for supervision, which greatly solves the problem of large labor consumption in cable laying and improves the speed. Taking 3×35~95 cross-linked polyvinyl chloride steel armored cable as an example, the speed can reach about 200m / h*person. Specifically including:

[0036] 1) After the cable arrives, first cut 1500-2000mm and send it to the testing department to test the conductor resistance, insulation resistance, thickness of the thinnest point of the insulation, change rate of tensile strength, elongation at break after aging, tensile strength after aging, elongation at break before aging, tensile strength before aging, withstand voltage test, insulation thickness, elongation change rate, and overall dimensions of the cable. After obtaining the cable re-inspection permit, the cable is placed in place according to the area.

[0037] 2) Before laying the cable, first clean the site, fix the cable bracket, and use a 2000V meter to check the insulation resistance again. The resistance value should not be less than 400MΩ.

[0038] 3) When laying the cable, first fix the cable conveyor to be used, and install the cable traction machine at the terminal, set all the equipment to the same frequency, and after debugging, the cable is sent out from the top of the cable drum and pulled by the traction rope. Two cables (ZA-YJV22-3×120+1×70mm2) are laid at the same time. Although affected by winter construction, the equipment is about 7,200 meters, and a total of 36 cables took less than two days.

[0039] 4) During the cable wiring process, it was found that the cable design capacity in the original design was relatively large. Although the incoming lines had been checked before laying and there were no problems, the internal terminals were relatively tight after the junction box was opened, so cable clamps were used to meet the needs of on-site use.

[0040] 5) In order to prevent discharge inside the equipment due to the close terminals, the copper nose is polished and separated by an insulating plate. After the line inlet is sealed with explosion-proof putty, the dust inside the junction box is cleaned and dried. When the junction box is restored, butter is used to apply to the edges to achieve sealing and anti-corrosion effects.

[0041] 6) After the wiring of the distribution cabinet is completed, in order to prevent the thyristor from absorbing dust due to the electromagnetic field, the patterned plate is cut to seal the base of the cabinet body, and explosion-proof putty is used to seal it.

[0042] The bridge, piping installation and wiring quality acceptance specifically includes:

[0043] 1) Check the horizontal, vertical, slope and direction of the cable tray installation. The spacing between the layers of the multi-layer cable tray is uniform, the curvature of the curved parts of each layer is consistent, and the bending radius meets the bending radius requirements of the cable laying.

[0044] 2) The cable tray is firmly connected to the bracket, the butt connection is firm and burr-free, and expansion gap is reserved. Reinforcement plates have been installed at the bolted connections, the bolts are tightened, and the nuts are on the outside of the slot plate.

[0045] 3) When the straight section of steel cable tray exceeds 30m and the aluminum alloy or fiberglass cable tray exceeds 15m, an expansion joint of no less than 20mm should be left.

[0046] 4) The holes for the protective tubes on the pallet bridge should be opened mechanically, and the opening position should be above 2 / 3 of the height of the bridge side wall.

[0047] 5) The inside of the cable tray is smooth and clean, without any debris or burrs.

[0048] 6) The cable tray has good grounding.

[0049] The cable installation quality acceptance specifically includes:

[0050] 1) There is no mechanical damage to the cable protective layer.

[0051] 2) The horizontal section of the cable fixing shall not exceed 1500mm, the vertical section shall not exceed 2000mm, and the bending radius shall not be less than 12D.

[0052] 3) All grounded points of the cable line should be in good contact with the grounding electrode, and the grounding resistance value should not exceed 4Ω.

[0053] 4) The cable terminals and cable connectors are firmly fixed, and the cable terminals are in good contact with the terminals of the connected equipment.

[0054] 5) Cable identification plates are complete, correct and clear.

[0055] The equipment debugging specifically includes:

[0056] 1) Before debugging the secondary circuit of the thyristor distribution cabinet, you must first carefully check the drawings, including the schematic diagram and installation wiring diagram, familiarize yourself with the structural characteristics and action principles of the thyristor distribution cabinet circuit, and confirm that the factory tests of the electrical equipment, instruments, relays and automatic devices in the circuit have been completed;

[0057] 2) Use a 1000V electric shake meter to measure the DC circuit, signal circuit, and insulation resistance to ground, and the results are no less than 1MΩ;

[0058] 3) Test the on-site temperature transmitter, using a handheld operator to generate a 4-20MA signal to simulate a 0-100% range;

[0059] 4) Short-circuit the distribution cabinet to the automatic control point of the DCS cabinet instrument between the cabinets, set up a cordon within 10m around the on-site equipment and assign dedicated personnel to guard it, power on the equipment for testing, adjust the power to 25%, 50%, 75%, and 100% respectively, and stay for 15 minutes, and record the central control feedback temperature in the main operation room; after the temperature rise is over, turn off the power of the electric heater equipment, and record the temperature drop curve, and the electrical debugging is completed.

[0060] The beneficial effects of the present invention are:

[0061] 1. According to the installation location of the regeneration gas electric heater, a ramp traction installation method was developed to solve the problem of installing horizontal equipment on the ground within a narrow range within the frame and reduce the cost of construction machinery;

[0062] 2. Each heater has 18 inlets. 18 3×120+1×70mm2 cables are connected to 9 inlet terminals. The space at the end of the heater is too small to accommodate extra cables. Before laying the cables, the cable layout is carried out, the cable length is reasonably calculated, and the inlet and wiring positions are determined, which saves cable usage and improves work efficiency.

[0063] 3. The size of the power distribution cabinet is larger than the size of the reserved hole of the substation. The combination of hoist and pulley was adopted to successfully complete the installation without damaging the finished building;

[0064] 4. The automatic temperature control system of the electric heater is interlocked and debugged, and a reasonable debugging method has been formulated, which is qualified in one debugging during the trial operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 This is a schematic diagram of the equipment body being installed.

[0066] Figure 2 and 3 This is a diagram of the cabinet lifting process. DETAILED DESCRIPTION

[0067] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0068] A regeneration gas electric heater construction process comprises the following steps in sequence: construction preparation, equipment installation and electrical instrument construction.

[0069] In this embodiment, the construction preparation includes equipment unpacking acceptance and equipment foundation acceptance; wherein, the equipment unpacking acceptance includes unpacking acceptance of on-site equipment and its accessories, and unpacking acceptance of distribution panels.

[0070] The equipment unpacking acceptance specifically includes:

[0071] 1) After the heater equipment arrives at the site, unpacking shall be carried out under good weather conditions.

[0072] 2) Before removing the packaging, confirm the appearance and remove the packaging after confirming that it is qualified.

[0073] 3) After removing the box packaging, count the contents according to the packing list and technical agreement:

[0074] 3.1) Check the equipment list, model and take inventory of accessories.

[0075] 3.2) Carry out material testing on special material equipment and accessories according to the technical agreement.

[0076] 3.3) Take inventory of accessories and replacement parts that are not being installed yet, keep video footage and collect them into the warehouse for separate storage.

[0077] The equipment basic acceptance specifically includes:

[0078] 1) Check the basic dimensions and appearance quality as required.

[0079] 2) Confirm the foundation elevation reference line and center position, use fine steel wire to mark the center line position of the horizontal and vertical axes, and then check the related dimensions such as flatness and verticality.

[0080] 3) Before the equipment is put in place, the foundation surface should be trimmed, the foundation surface to be grouting should be chiseled into a rough surface, the oily concrete should be scraped off, and the lower surface of the equipment base should be carefully cleaned to remove rust, oil, etc. At least 6 hours before grouting, the foundation surface and foundation bolt holes to be poured with concrete should be thoroughly wetted, and then the water on the foundation surface and in the bolt holes must be blown dry with compressed air, wiped dry with a rag, or drained with a pump.

[0081] In this embodiment, the equipment installation includes equipment positioning and equipment alignment.

[0082] Wherein, the equipment in place specifically includes: Figure 1 During the installation of the equipment, the equipment is located directly below the steel structure. The upper structure needs to be dismantled when it is hoisted by a crane. In order to reduce the construction cost without dismantling the completed structure, the installation method shown in the figure is adopted; to prevent the equipment from falling off during installation, a 5t double hoist is used for coordinated traction. After confirmation by the structural professional, the hoist is fixed on the steel structure directly in front of the equipment foundation for installation; since the equipment body is made of S30408 ​​material, in order to protect the equipment body, a 10t sling is used for pulling during transportation, and the contact position of the equipment is padded; during the sliding process of the equipment, a DN50 thick-walled steel pipe is used as a roller, and a 10mm steel plate is used for padding In order to ensure that the equipment does not get stuck during movement due to the sliding of the rollers, the number of rollers was increased, and personnel were arranged to cooperate synchronously to slide the rollers out of the rear of the equipment base and move them forward again; in order to reduce the longitudinal force when the hoist is pulled, the length of the sliding platform was appropriately increased, and a 10mm steel plate was used on the sandy ground to prevent overturning and collapse during sliding; sleepers were used to support the bottom of the sliding platform to ensure that all hardened cement floors were not damaged; after the equipment was transported to the predetermined position on the foundation, a 10t hydraulic jack was used to lift the equipment under the equipment base, the rollers and steel plates were pulled out, and temporary pads were placed on the base for support.

[0083] The equipment alignment specifically includes: the regeneration gas electric heater is the starting point of the process piping of the entire gasoline hydrogenation unit as the raw material preheating equipment. In order to ensure the subsequent pipeline assembly, the accuracy of the equipment position needs to be ensured; during the initial alignment, a precise level is used to carefully level the base in the vertical and horizontal directions, so that the anchor bolts are naturally vertical in the reserved bolt holes, with a spacing greater than 15mm from the hole wall and do not touch the bottom of the hole; during the primary grouting, high-strength non-shrinkage grouting material is used to pour 100mm below and 100mm above the anchor bolt hole. To avoid the formation of bubbles, stir the grouting material; tighten the anchor bolts when the grouting material reaches more than 75% of the design strength. After tightening the nuts, the bolts should protrude 2-3 pitches from the nuts; place a set of formal shims on the left and right of each anchor bolt and on the base beam. After removing the temporary shims, use a frame level to perform secondary alignment of the equipment and perform secondary grouting. The secondary grouting work must be completed in one go with the cooperation of the installers. After the secondary grouting strength reaches the standard, pour C20 concrete into the base to ensure stable operation of the subsequent equipment.

[0084] In this embodiment, the electrical instrumentation construction includes cabinet construction, cable construction, equipment wiring and equipment debugging.

[0085] The cabinet construction includes cabinet hoisting and cabinet installation inspection; the cabinet hoisting specifically includes: Figure 2 and 3 As shown, during the hoisting process, the protected cabinet is first hoisted to the reserved hoisting platform on the second floor. Because the inside of the substation is too high, in order to facilitate the tilted cabinet to move inward as much as possible, a movable hoisting device group composed of a hoist and a pulley is used to move it; the cabinet installation inspection specifically includes: In accordance with the "Electrical Installation Engineering Panel, Cabinet and Secondary Circuit Wiring Construction and Acceptance Specification" (GB 50171-2012), the cabinet installation is inspected, and the inspection contents are as follows:

[0086] 3.1) Appearance inspection

[0087] Serial number project Permissible deviation 1 Top of two adjacent cabinets ≤2mm 2 Top of the row tray ≤5mm 3 Disk Deviation Adjacent plate edges ≤1mm 4 Column plate ≤5mm 5 Disk seam ≤2mm 6 Verticality (per meter) 1.5mm 7 Exterior paint The cabinet paint surface is intact and undamaged

[0088] 3.2) Component inspection

[0089] The center lines of the moving and static contacts are consistent, and the contacts are in close contact; the switching contacts of the secondary circuit auxiliary switch have accurate movement and reliable contact.

[0090] After checking and confirming the above contents, in order to prevent the welding current from damaging the internal electrical components, the cabinet is fixed by bolt connection (tightening torque 75N.m) and the bolts are marked. After completing the above work, the cabinet body and internal components are grounded and tested for insulation. The grounding resistance is not greater than 1Ω, and the insulation resistance is not less than 1000MΩ.

[0091] As a further improvement of the present invention, the cable construction and equipment wiring include: bridge and piping installation; cable laying and wiring; bridge and piping installation and wiring quality acceptance; cable installation quality acceptance.

[0092] The bridge and piping installation specifically includes:

[0093] 1) The starting point of the heater cable tray is at the C2 substation on the south side of the gasoline hydrogenation unit, and a span is made to connect the internal bridge of the substation. During the connection process, close communication is carried out with the designer to optimize the cable laying line and reduce the number of spans.

[0094] 2) The original design used 32 DN100 galvanized steel pipes as cable protection pipes for laying from the pipe gallery to the equipment. However, considering the small space of the actual construction area on site, the bending radius of the cable protection pipe cannot meet the requirements of the specification. In addition, the cable here is 3×120+1×70mm2 armored cable, and the cable pipe spacing cannot meet the cable heat dissipation requirements. In order to ensure the normal laying of the cable and not affect the normal use of the equipment, the original design laying method was changed to laying in a double-layer cable bridge, which reduced a lot of construction costs and material costs.

[0095] 3) At the equipment wiring buckle, due to the low elevation of the on-site equipment design, the cable bending radius cannot meet the specifications of the specification no matter how it is bent. The protection pipe and bridge at the line inlet are cancelled, and a cable protection pool is added at the heater line inlet. The cable protection pool adopts a brick structure and is filled with coarse sand to protect the cable and ensure the heat dissipation of the cable.

[0096] 4) The instrument cables are laid along the bridge, and the distance from the bridge to the equipment is too long. In order to ensure production safety in the explosion-proof area, the cables originally designed to be laid through pipes are changed to be laid along 50×50mm trough boxes.

[0097] The cable laying and wiring are as follows: the latest linkage cable laying equipment is adopted, which has stable operation, high transmission speed and can be remotely controlled and linked. In cable laying, it is only necessary to set up according to the number of equipment, and each equipment can be equipped with one or two people for supervision, which greatly solves the problem of large labor consumption in cable laying and improves the speed. Taking 3×35~95 cross-linked polyvinyl chloride steel armored cable as an example, the speed can reach about 200m / h*person. Specifically including:

[0098] 1) After the cable arrives, first cut 1500-2000mm and send it to the testing department to test the conductor resistance, insulation resistance, thickness of the thinnest point of the insulation, change rate of tensile strength, elongation at break after aging, tensile strength after aging, elongation at break before aging, tensile strength before aging, withstand voltage test, insulation thickness, elongation change rate, and overall dimensions of the cable. After obtaining the cable re-inspection permit, the cable is placed in place according to the area.

[0099] 2) Before laying the cable, first clean the site, fix the cable bracket, and use a 2000V meter to check the insulation resistance again. The resistance value should not be less than 400MΩ.

[0100] 3) When laying the cable, first fix the cable conveyor to be used, and install the cable traction machine at the terminal, set all the equipment to the same frequency, and after debugging, the cable is sent out from the top of the cable drum and pulled by the traction rope. Two cables (ZA-YJV22-3×120+1×70mm2) are laid at the same time. Although affected by winter construction, the equipment is about 7,200 meters, and a total of 36 cables took less than two days.

[0101] 4) During the cable wiring process, it was found that the cable design capacity in the original design was relatively large. Although the incoming lines had been checked before laying and there were no problems, the internal terminals were relatively tight after the junction box was opened, so cable clamps were used to meet the needs of on-site use.

[0102] 5) In order to prevent discharge inside the equipment due to the close terminals, the copper nose is polished and separated by an insulating plate. After the line inlet is sealed with explosion-proof putty, the dust inside the junction box is cleaned and dried. When the junction box is restored, butter is used to apply to the edges to achieve sealing and anti-corrosion effects.

[0103] 6) After the wiring of the distribution cabinet is completed, in order to prevent the thyristor from absorbing dust due to the electromagnetic field, the patterned plate is cut to seal the base of the cabinet body, and explosion-proof putty is used to seal it.

[0104] The bridge, piping installation and wiring quality acceptance specifically includes:

[0105] 1) Check the horizontal, vertical, slope and direction of the cable tray installation. The spacing between the layers of the multi-layer cable tray is uniform, the curvature of the curved parts of each layer is consistent, and the bending radius meets the bending radius requirements of the cable laying.

[0106] 2) The cable tray is firmly connected to the bracket, the butt connection is firm and burr-free, and expansion gap is reserved. Reinforcement plates have been installed at the bolted connections, the bolts are tightened, and the nuts are on the outside of the slot plate.

[0107] 3) When the straight section of steel cable tray exceeds 30m and the aluminum alloy or fiberglass cable tray exceeds 15m, an expansion joint of no less than 20mm should be left.

[0108] 4) The holes for the protective tubes on the pallet bridge should be opened mechanically, and the opening position should be above 2 / 3 of the height of the bridge side wall.

[0109] 5) The inside of the cable tray is smooth and clean, without any debris or burrs.

[0110] 6) The cable tray has good grounding.

[0111] The cable installation quality acceptance specifically includes:

[0112] 1) There is no mechanical damage to the cable protective layer.

[0113] 2) The horizontal section of the cable fixing shall not exceed 1500mm, the vertical section shall not exceed 2000mm, and the bending radius shall not be less than 12D.

[0114] 3) All grounded points of the cable line should be in good contact with the grounding electrode, and the grounding resistance value should not exceed 4Ω.

[0115] 4) The cable terminals and cable connectors are firmly fixed, and the cable terminals are in good contact with the terminals of the connected equipment.

[0116] 5) Cable identification plates are complete, correct and clear.

[0117] The equipment debugging specifically includes:

[0118] 1) Before debugging the secondary circuit of the thyristor distribution cabinet, you must first carefully check the drawings, including the schematic diagram and installation wiring diagram, familiarize yourself with the structural characteristics and action principles of the thyristor distribution cabinet circuit, and confirm that the factory tests of the electrical equipment, instruments, relays and automatic devices in the circuit have been completed;

[0119] 2) Use a 1000V electric shake meter to measure the DC circuit, signal circuit, and insulation resistance to ground, and the results are no less than 1MΩ;

[0120] 3) Test the on-site temperature transmitter, using a handheld operator to generate a 4-20MA signal to simulate a 0-100% range;

[0121] 4) Short-circuit the distribution cabinet to the automatic control point of the DCS cabinet instrument between the cabinets, set up a cordon within 10m around the on-site equipment and assign dedicated personnel to guard it, power on the equipment for testing, adjust the power to 25%, 50%, 75%, and 100% respectively, and stay for 15 minutes, and record the central control feedback temperature in the main operation room; after the temperature rise is over, turn off the power of the electric heater equipment, and record the temperature drop curve, and the electrical debugging is completed.

[0122] This process is intended to solve the installation of small equipment in a narrow construction site environment and under the influence of external conditions. Through reasonable process matching, multi-professional installation at the same time, reasonable modifications are made to the unreasonable, difficult to construct, and wasteful parts of the original design to reduce construction and material costs. The latest cable laying equipment and innovative technologies are introduced during the electrical and instrumentation construction process to reduce labor costs during the construction process and improve construction quality and efficiency; this process focuses on solving actual problems on site, solving special problems specifically, and reasonably arranging construction. The overall installation and construction cost is reduced by more than 40%, and the construction period is shortened by about 50%.

[0123] The technical means disclosed in the scheme of the present invention are not limited to the technical means disclosed in the above-mentioned implementation mode, but also include technical schemes composed of any combination of the above-mentioned technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. A construction process for a regeneration gas electric heater, characterized in that: The following steps are included in sequence: Construction preparation, equipment installation and electrical instrumentation construction; The construction preparation includes equipment unpacking acceptance and equipment foundation acceptance; wherein, the equipment unpacking acceptance includes unpacking acceptance of on-site equipment and its accessories, and unpacking acceptance of distribution panels and cabinets; The equipment installation includes equipment positioning and equipment alignment; The equipment placement specifically includes: during the equipment installation process, the equipment is located directly below the steel structure, and the upper structure needs to be dismantled when using a crane for lifting; to prevent the equipment from falling off during the installation process, a double hoist is used for coordinated traction, and the hoist is fixed on the steel structure directly in front of the equipment foundation for installation; to protect the equipment body, a sling is used for pulling during transportation, and the contact position of the equipment is padded; during the sliding process of the equipment, thick-walled steel pipes are used as rollers, and steel plates are used for padding. In order to ensure that the equipment does not get stuck during the movement due to the sliding of the rollers during the sliding process, the number of rollers is increased, and personnel are arranged to cooperate synchronously to slide the rollers out of the rear of the equipment base and move it forward again; in order to reduce the longitudinal force when the hoist is pulled, the length of the sliding platform is increased, and steel plates are used on the sandy ground to prevent overturning and collapse during the sliding process; sleepers are used to support the bottom of the sliding platform to ensure that all hardened cement floors are not damaged; after the equipment is transported to the predetermined position on the foundation, a hydraulic jack is used to lift the equipment under the equipment base, the rollers and steel plates are pulled out, and temporary pads are placed at the base for support; The equipment alignment specifically includes: the regeneration gas electric heater is the starting point of the process piping of the entire gasoline hydrogenation unit as the raw material preheating equipment. In order to ensure the subsequent pipeline assembly, the accuracy of the equipment position needs to be ensured; during the initial alignment, a precise level is used to carefully level the base in the longitudinal and transverse directions so that the anchor bolts are naturally vertical in the reserved bolt holes and do not touch the bottom of the holes; high-strength non-shrinkage grouting material is used for pouring during the first grouting, and the grouting material must be stirred during grouting to avoid the formation of bubbles; the anchor bolts are tightened after the grouting material reaches more than 75% of the design strength, and after tightening the nuts, the bolts are exposed by 2-3 pitches of the nuts; a set of formal shims are placed on the left and right sides of each anchor bolt and at the base crossbeam position, and after the temporary shims are pulled out, a frame level is used to perform secondary alignment and secondary grouting on the equipment. The secondary grouting work must be completed at one time with the cooperation of the installers, and concrete is poured into the base after the secondary grouting strength meets the standard to ensure the subsequent stable operation of the equipment; The electrical instrumentation construction includes cabinet construction, cable construction, equipment wiring and equipment debugging; The cabinet construction includes cabinet hoisting and cabinet installation inspection; wherein, the cabinet hoisting specifically includes: during the hoisting process, the cabinet that has been well protected is first hoisted to the hoisting platform reserved at the second floor, and a movable hoisting device group composed of a hoist and a pulley is used to move it; The cable construction and equipment wiring include: bridge and piping installation; cable laying and wiring; bridge and piping installation and wiring quality acceptance; cable installation quality acceptance; The equipment debugging specifically includes: 1) Before debugging the secondary circuit of the thyristor distribution cabinet, you must first carefully check the drawings, including the schematic diagram and installation wiring diagram, familiarize yourself with the structural characteristics and action principles of the thyristor distribution cabinet circuit, and confirm that the factory tests of the electrical equipment, instruments, relays and automatic devices in the circuit have been completed; 2) Use a 1000V electric shake meter to measure the insulation resistance of the DC circuit and signal circuit to ground, and the results are not less than 1MΩ; 3) Test the on-site temperature transmitter and use a handheld operator to generate a 4-20MA signal to simulate a 0-100% range; 4) Short-circuit the automatic control point of the DCS cabinet instrument between the power distribution cabinet and the cabinet, set up a cordon within 10m around the on-site equipment and assign dedicated personnel to guard it, power on the equipment for test, adjust the power to 25%, 50%, 75%, and 100% respectively, and stay for 15 minutes, and record the central control feedback temperature in the main operation room; after the temperature rise is completed, turn off the power of the electric heater equipment, and record the temperature drop curve, and the electrical commissioning is completed.

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