Oil tank bottom edge plate waterproof material and waterproof process

Abstract

The invention discloses a waterproof material for the bottom edge plate of an oil tank, comprising component A and component B, wherein the component A is a prepolymer with an isocyanate group (-NCO), and the component B is a color paste composed of a chain extender, a filler, a pigment, an antioxidant, and an ultraviolet absorber. The components A and B are mixed in a ratio of 1:2 to prepare a primer. A waterproof process for the bottom edge plate of an oil tank, wherein the waterproof material is injected into the gap between the edge plate and the base through a glue injection device. By filling the side wall of the oil tank, the top of the edge plate, the gap between the edge plate and the base, and the side of the base with glue, the glue covers the oil cylinder, the edge plate, and the base in all directions, thereby improving the waterproofness and weather resistance, and at the same time making the edge plate and the base have strong adhesion and high elasticity.

Description

Technical Field

[0001] The invention relates to the technical field of oil tank construction, in particular to a waterproof material and a waterproof process for an oil tank bottom edge plate. Background Art

[0002] During the installation of the oil tank, the edge plate at the bottom of the oil tank needs to be treated for corrosion resistance, so waterproof materials are needed to make it waterproof, weather-resistant, have strong adhesion with the edge plate and the base, and have high elasticity. The so-called waterproofness requires that the waterproof layer is a complete and continuous whole that can truly isolate the invasion of water, atmosphere, etc.; the so-called weather resistance requires that the waterproof material can withstand atmospheric corrosion and ultraviolet radiation, and cannot produce cracks that affect the waterproof performance, and does not flow at high temperatures and does not crack at low temperatures; high elasticity requires that the material can adapt to the deformation of the bottom plate caused by the movement of the oil tank or the change of load.

[0003] However, when such processes are currently being carried out, it is difficult for waterproof materials to achieve the above-mentioned effects. In addition, during the construction process, it is difficult to inject glue into the gap between the edge plate and the base, and the glue cannot be pressed immediately after injection, resulting in low construction efficiency. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a waterproof material and a waterproof process for an oil tank bottom edge plate to solve the problems mentioned in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A waterproof material for the bottom edge plate of an oil tank comprises a component A and a component B, wherein the component A is a prepolymer with an isocyanate group (-NCO), and the component B is a color paste composed of a chain extender, a filler, a pigment, an antioxidant, and an ultraviolet absorber. The component A and the component B are mixed in a ratio of 1:2 to obtain a primer.

[0007] The present invention also provides a waterproof process for the bottom edge plate of an oil tank, using the waterproof material, comprising the following steps:

[0008] S1: Treat the base to keep it clean, dry and firm. At the same time, level the damaged base and the fallen concrete with 1:2.5 cement mortar and wait for it to dry;

[0009] S2: Knock out all the corroded and loose cement blocks on the edge of the oil tank base, modify the edges of the caulking type oil tank base into a water-spreading slope type, and completely remove the corroded and loose old paint film, rust, and cement debris on the edge plate base surface. Use a surface treatment agent to remove the rust and old paint film in the corrosion pits on the edge plate base surface that are difficult to remove;

[0010] S3: Apply mortar or paste the platform edge line on the edge of the cement base and the edge plate, with a distance of at least 10mm from the edge plate;

[0011] S4: Mix component A and component B in a ratio of 1:2 to prepare a primer, add a catalyst, and stir thoroughly for no less than 1 minute;

[0012] S5: Apply the first coat of primer on the edge board with a thickness of 5 to 10 cm;

[0013] S6: Mix elastic rubber powder and primer to make cement, fill the gap between the edge plate and the base with cement using a filling device, and then cover the tank wall, the edge plate, the top surface of the base and the base wall with cement, and press them to form sealing cement, the top surface of which is a flat inclined surface;

[0014] S7: Apply a mid-coat paint on the sealing glue and fill the uneven areas on the surface of the sealing glue;

[0015] S8: Then cover with the first layer of elastic nylon cloth, making sure there are no wrinkles or pores to avoid moisture retention;

[0016] S9: After the coating is dry, apply topcoat, then apply a layer of elastic nylon cloth. After the coating is dry, apply two more coats of topcoat to complete the construction.

[0017] Preferably, in step S4, the amount of the catalyst added is 5-10% by weight of component B.

[0018] Preferably, in step S6, the top surface of the sealing adhesive is a flat inclined surface with an angle of 7 to 10 degrees.

[0019] Preferably, the filling device in step S6 comprises a horizontal displacement mechanism, a slide seat arranged on the horizontal displacement mechanism, an arc-shaped plate connected to the top of the slide seat and extending forward, an arc-shaped hole is opened on the arc-shaped plate, a rotating shaft is rotatably connected to the slide seat, the rotating shaft is located at the center of the arc-shaped plate, a swing rod is fixed to the rotating shaft, the swing rod is located below the arc-shaped plate, a sliding rod is rotatably connected to the swing rod, the sliding rod is slidably connected in the arc-shaped hole, a bracket is connected to the slide seat, a first driving mechanism for driving the rotating shaft to rotate is provided on the bracket, and the upper end of the sliding rod is connected to An L-shaped seat, with a glue gun hinged on the L-shaped seat, an electric telescopic rod hinged on the lower part of one side of the L-shaped seat, a positioning plate hinged on the upper end of the electric telescopic rod, the glue gun is installed on the positioning plate, and a U-shaped notch is provided on the upper part of the positioning plate. Shafts are rotatably connected to both sides of the L-shaped seat, and first cylinders are fixedly connected to the two shafts. Pressing plates are movably connected to the telescopic ends of the two first cylinders, and the stroke of the two first cylinders is greater than the length of the glue gun, and the two first cylinders are abutted in the U-shaped notch, and a second driving mechanism for driving the shaft to rotate is provided on one side of the L-shaped seat.

[0020] Preferably, the horizontal displacement mechanism includes a base, bearing seats connected to both ends of the base, a screw rod rotatably connected to the two bearing seats, a guide rod connected to the two bearing seats, and a first motor installed at one end of the base, the first motor is transmission-connected to the screw rod, the slide is threadedly connected to the screw rod, and the slide is slidably connected to the guide rod.

[0021] Preferably, the first driving mechanism includes a second motor mounted on a bracket, a first transmission shaft connected to the second motor via a coupling, a first main gear connected to the first transmission shaft, and a first sub-gear connected to the rotating shaft, and the first main gear is meshed with the first sub-gear.

[0022] Preferably, the glue injection gun includes a gun body, a gun nozzle connected to one end of the gun body, a glue inlet pipe connected to the gun body, a piston slidably arranged in the gun body, and a second cylinder sealably installed at one end of the gun body, the second cylinder is connected to the piston, and both sides of the gun body are connected to hinge shafts, and are hinged to the L-shaped seat through the hinge shafts, and the gun body is installed on the positioning plate.

[0023] Preferably, the second driving mechanism includes a supporting plate connected to the L-shaped seat, a third motor arranged on the supporting plate, a second transmission shaft connected to the third motor through a coupling, a second main gear connected to the second transmission shaft, and a second sub-gear fixedly connected to one of the shafts, and the second main gear is meshed with the second sub-gear.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) By filling the side wall of the oil tank, the top of the edge plate, the gap between the edge plate and the base, and the side of the base with glue, the oil tank, the edge plate, and the base are fully covered with glue, which improves the waterproofness and weather resistance. At the same time, the edge plate and the base have strong adhesion and high elasticity.

[0026] (2) During the construction process, glue is injected into the gap between the edge plate and the base through the glue injection device. After the glue is injected, the glue can be pressed into the gap through the pressing plate. There is no need to manually take an additional pressing device, which improves the efficiency of injecting glue between the edge plate and the base. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of a glue injection device of the present invention;

[0028] Figure 2 It is a schematic diagram after the first cylinder is turned over;

[0029] Figure 3 Schematic diagram of the glue injection device when preparing for glue injection;

[0030] Figure 4 It is a partial top view of the glue injection device;

[0031] Figure 5 It is a partial schematic diagram of the glue injection gun and the pressing plate;

[0032] Figure 6 This is a schematic diagram of a glue injection gun;

[0033] Figure 7 This is a schematic diagram of the oil tank, edge plate and base after being treated with waterproofing technology;

[0034] In the figure: 1-sliding seat, 2-arc plate, 3-arc hole, 4-rotating shaft, 5-rocker, 6-sliding rod, 7-bracket, 8-L-shaped seat, 9-electric telescopic rod, 10-positioning plate, 11-shaft rod, 12-first cylinder, 13-pressing plate, 14-U-shaped notch, 15-base, 16-screw rod, 17-guide rod, 18-first motor, 19-second motor, 20-first main gear, 21-first sub-gear, 22-gun body, 23-gun nozzle, 24-rubber inlet pipe, 25-piston, 26-second cylinder, 27-bearing plate, 28-third motor, 29-second main gear, 30-second sub-gear, 31-base, 32-oil tank, 33-edge plate, 34-sealing glue, 35-primer, 36-nylon cloth, 37-middle coating, 38-top coating, 39-fastening nut. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] A waterproof material for the bottom edge plate of an oil tank comprises a component A and a component B, wherein the component A is a prepolymer with an isocyanate group (-NCO), and the component B is a color paste composed of a chain extender, a filler, a pigment, an antioxidant, and an ultraviolet absorber. The component A and the component B are mixed in a ratio of 1:2 to obtain a primer.

[0037] The present invention also provides a waterproof process for the bottom edge plate of an oil tank, using the waterproof material, comprising the following steps:

[0038] S1: Treat the base to keep it clean, dry and firm. At the same time, level the damaged base and the fallen concrete with 1:2.5 cement mortar and wait for it to dry;

[0039] S2: Knock out all the corroded and loose cement blocks on the edge of the oil tank base, modify the edges of the caulking type oil tank base into a water-spreading slope type, and completely remove the corroded and loose old paint film, rust, and cement debris on the edge plate base surface. Use a surface treatment agent to remove the rust and old paint film in the corrosion pits on the edge plate base surface that are difficult to remove; make the base surface of the waterproof and anti-corrosion layer clean, dry, firm, oil-free, and loose;

[0040] S3: Apply mortar or paste the platform edge line on the edge of the cement base and the edge plate, with a distance of at least 10mm from the edge plate;

[0041] S4: Mix component A and component B in a ratio of 1:2 to prepare a primer, add a catalyst, stir thoroughly, and stir for no less than 1 minute; the amount of catalyst is 5-10% of the weight of component B. When the room temperature is about 20°C, the amount of catalyst can be adjusted accordingly according to the ambient temperature to accelerate or slow down the curing speed; the prepared material should be used up within half an hour, and the user can adjust the viscosity with acetone, xylene or ethyl acetate according to the needs of construction, whichever is more convenient for construction (in principle, the amount of diluent added should not exceed 10%);

[0042] S5: Apply the first coat of primer on the edge board with a thickness of 5 to 10 cm; the ratio of A and B should be well controlled, A: B = 1: 2, and it should be thinner to control the viscosity, otherwise bubbles will easily be generated, affecting the adhesion of the coating. Adjust the catalyst according to the ambient temperature to control the curing time;

[0043] S6: Mixing elastic rubber powder with primer to prepare glue, specifically, 5kg primer and 25kg elastic rubber powder are mixed; then the gap between the edge plate and the base is filled with glue using a filling device, and then the tank wall, the edge plate, the top surface of the base and the base wall are covered with glue, and pressed to form sealing glue, the top surface of which is a flat 7-10° angle slope;

[0044] S7: Apply the intermediate paint on the sealing glue, adjust the consistency according to the site conditions, and fill the uneven areas on the surface of the sealing glue;

[0045] S8: Then cover with the first layer of elastic nylon cloth, making sure there are no wrinkles or pores to avoid moisture retention;

[0046] S9: After the coating is dry, apply topcoat and then apply a layer of elastic nylon cloth. After the coating is dry, apply two more coats of topcoat to ensure fullness and smoothness to complete the construction.

[0047] It should be noted that construction should not be carried out when the temperature is below 0℃. The waterproof sealing glue for the edge plate of the tank bottom should be stored in a cool, dry, and closed place, away from direct sunlight or high temperature, and away from fire. The shelf life of the special sealing glue for the edge plate of the tank bottom is 12 months.

[0048] See also Figure 1 The filling device in step S6 includes a horizontal displacement mechanism, a slide 1 arranged on the horizontal displacement mechanism, and an arc plate 2 connected to the top of the slide and extending forward. Specifically, the horizontal displacement mechanism includes a base 15, a bearing seat connected to both ends of the base, a screw 16 rotatably connected to the two bearing seats, a guide rod 17 connected to the two bearing seats, and a first motor 18 installed at one end of the base. The first motor 18 is connected to the screw 16 in a transmission manner, the slide 1 is threadedly connected to the screw 16, and the slide 1 is slidably connected to the guide rod 17. When injecting glue, place the external support platform on one side of the base, set the horizontal displacement mechanism on the support platform, and then start the first motor 18 to drive the screw 16 to rotate, which can drive the slide 1 to move toward the edge plate.

[0049] like Figure 1 , Figure 2 , Figure 3 As shown, an arc-shaped hole 3 is provided on the arc-shaped plate 2, a rotating shaft 4 is rotatably connected to the slide 1, the rotating shaft 4 is located at the center of the arc-shaped plate, a rocker 5 is fixed to the rotating shaft 4, the rocker 5 is located below the arc-shaped plate 2, a sliding rod 6 is rotatably connected to the rocker 5, the sliding rod 6 is slidably connected in the arc-shaped hole 3, a bracket 7 is connected to the slide 1, and a first driving mechanism for driving the rotating shaft to rotate is provided on the bracket 7. Specifically, the first driving mechanism includes a second motor 19 installed on the bracket, a first transmission shaft connected to the second motor through a coupling, a first main gear 20 connected to the transmission shaft, and a first sub-gear 21 connected to the rotating shaft, and the first main gear 20 is meshed with the first sub-gear 21. The second motor 19 works, and through the cooperation of the first main gear 20 and the first sub-gear 21, it drives the rotating shaft 4 to rotate, and the rotating shaft 4 drives the swing rod 5 to rotate. Since the rotating shaft 4 is cocentric with the arc plate 2, the swing rod 5 will drive the sliding rod 6 to slide in the arc hole 3 during the rotation process, thereby adjusting the direction of the glue injection gun to increase the glue injection range.

[0050] like Figure 1 , Figure 4 , Figure 5 and Figure 6As shown, the upper end of the slide bar 6 is connected to an L-shaped seat 8, and a glue injection gun is hinged on the L-shaped seat 8. The glue injection gun includes a gun body 22, a gun nozzle 23 connected to one end of the gun body, a glue inlet pipe 24 connected to the gun body, a piston 25 slidably arranged in the gun body, and a second cylinder 26 sealed and installed at one end of the gun body. The second cylinder 26 is connected to the piston 25, wherein the glue inlet pipe 24 is connected to the glue supply device through a pipeline, and a control valve is arranged on the pipeline for controlling the opening and closing of the glue inlet pipe. Both sides of the gun body 22 are connected to hinge shafts, and are hinged to the L-shaped seat 8 through the hinge shafts. The lower part of one side of the L-shaped seat 8 is hinged to an electric telescopic rod 9. A positioning plate 10 is hinged at the upper end of the electric telescopic rod 9, and the gun body 22 is installed on the positioning plate 10. A U-shaped notch 14 is provided on the upper part of the positioning plate 10. The two sides of the L-shaped seat 8 are rotatably connected with the shaft rod 11, and the two shaft rods 11 are fixedly connected with the first cylinders 12. The telescopic ends of the two first cylinders 12 are movably connected with a pressing plate 13, and the stroke of the two first cylinders 12 is greater than the length of the glue injection gun, so that after the two first cylinders 12 are extended, the pressing plate 13 can be bypassed by the end of the gun nozzle 23. When the pressing plate is not in use, the two first cylinders 12 are against the U-shaped notch 14, and a second driving mechanism for driving the shaft rod 11 to rotate is provided on one side of the L-shaped seat 8.

[0051] Specifically, the second driving mechanism includes a carrier plate 27 connected to the L-shaped seat, a third motor 28 disposed on the carrier plate, a second transmission shaft connected to the third motor through a coupling, a second main gear 29 connected to the second transmission shaft, and a second sub-gear 30 fixedly connected to one of the shafts, and the second main gear 29 is meshed with the second sub-gear 30. When the third motor 28 is started, the cooperation of the second main gear 29 and the second sub-gear 30 can drive the two first cylinders 12 to rotate, so that the pressing plate 13 faces the glue filling position, and the pressing plate 13 is pushed by the extension of the first cylinder 12 to press the glue.

[0052] In this embodiment, Figure 5 As shown, the shaft 11 is threadedly connected with a fastening nut 39 near the L-shaped seat. The fastening nut 39 is screwed to press against the L-shaped seat 8, so that the shaft 11 can be fixed. When the shaft 11 needs to be driven to rotate, the fastening nut 39 is loosened. When the pressing plate 13 is to squeeze the cement, the fastening nut 39 is tightened to prevent the first cylinder 12 from rotating under the action of external force when squeezing the cement.

[0053] In summary, the method of injecting glue into the gap between the edge plate and the base by means of the filling device is as follows:

[0054] The glue gun is located above the base and aligned with the gap between the edge plate 33 and the base 31. The glue inlet pipe 24 is then connected to the glue storage device. The horizontal displacement mechanism is then used to drive the slide 1 to move toward the oil tank 32. The angle of the gun nozzle 23 is adjusted by the electric telescopic rod 9. The glue is then sent into the gun body 22 through the pump body. The second cylinder 26 is controlled to extend. The piston 25 pushes the glue to be discharged from the gun nozzle 23. After the glue is injected, the two first cylinders 12 are controlled to extend. The third motor 28 is then started. The second main gear 29 and the second sub-gear 30 cooperate to drive the two first cylinders 12 to rotate, so that the pressure plate 13 bypasses the gun nozzle 23 and contacts the base 31. The second cylinder 12 is then controlled to continue to extend. At the same time, the pressure plate 13 is driven to press the glue through the dual action of the horizontal displacement mechanism.

[0055] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A waterproofing process for the bottom edge plate of an oil tank, characterized in that: The following steps are involved: S1: Treat the base to keep it clean, dry and firm. At the same time, level the damaged base and the fallen concrete with 1:2.5 cement mortar and wait for it to dry; S2: Knock out all the corroded and loose cement blocks on the edge of the oil tank base, modify the edges of the caulking type oil tank base into a water-spreading slope type, and completely remove the corroded and loose old paint film, rust, and cement debris on the edge plate base surface. Use a surface treatment agent to remove the rust and old paint film in the corrosion pits on the edge plate base surface that are difficult to remove; S3: Apply mortar or paste the platform edge line on the edge of the cement base and the edge plate, with a distance of at least 10mm from the edge plate; S4: preparing a primer: the primer comprises a component A and a component B, wherein the component A is a prepolymer having an isocyanate group (-NCO), and the component B is a color paste consisting of a chain extender, a filler, a pigment, an antioxidant, and an ultraviolet absorber. The component A and the component B are mixed in a ratio of 1:2 to prepare a primer, and a catalyst is added and stirred thoroughly for not less than 1 minute; S5: Apply the first coat of primer on the edge board with a thickness of 5 to 10 cm; S6: Mix elastic rubber powder and primer to make cement, fill the gap between the edge plate and the base with cement using a filling device, and then cover the tank wall, the edge plate, the top surface of the base and the base wall with cement, and press them to form sealing cement, the top surface of which is a flat inclined surface; S7: Apply a mid-coat paint on the sealing glue and fill the uneven areas on the surface of the sealing glue; S8: Then cover with the first layer of elastic nylon cloth, making sure there are no wrinkles or pores to avoid moisture retention; S9: After the coating is dry, apply topcoat, then apply a layer of elastic nylon cloth, and then apply two coats of topcoat after the surface is dry to complete the construction; The filling device in step S6 comprises a horizontal displacement mechanism, a slide (1) arranged on the horizontal displacement mechanism, an arc-shaped plate (2) connected to the top of the slide and extending forward, the arc-shaped plate (2) is provided with an arc-shaped hole (3), the slide (1) is rotatably connected to a rotating shaft (4), the rotating shaft (4) is located at the center of the arc-shaped plate, a swing rod (5) is fixed to the rotating shaft (4), the swing rod (5) is located below the arc-shaped plate (2), a sliding rod (6) is rotatably connected to the swing rod (5), the sliding rod (6) is slidably connected in the arc-shaped hole (3), the slide (1) is connected to a bracket (7), the bracket (7) is provided with a first driving mechanism for driving the rotating shaft to rotate, the upper end of the sliding rod (6) is connected to an L-shaped seat (8), the L-shaped seat A glue gun is hinged on the upper portion of the L-shaped seat (8), an electric telescopic rod (9) is hinged on the lower portion of one side of the L-shaped seat (8), a positioning plate (10) is hinged on the upper end of the electric telescopic rod (9), the glue gun is mounted on the positioning plate (10), a U-shaped notch (14) is provided on the upper portion of the positioning plate (10), shafts (11) are rotatably connected on both sides of the L-shaped seat (8), first cylinders (12) are fixedly connected to the two shafts (11), a pressing plate (13) is movably connected to the telescopic ends of the two first cylinders (12), and the stroke of the two first cylinders (12) is greater than the length of the glue gun, the two first cylinders (12) are abutted against the U-shaped notch (14), and a second driving mechanism for driving the shaft (11) to rotate is provided on one side of the L-shaped seat (8).

2. The waterproofing process for the bottom edge plate of an oil tank according to claim 1 is characterized in that: In step S4, the amount of catalyst added is 5-10% of the weight of component B.

3. The waterproofing process for the bottom edge plate of an oil tank according to claim 1 is characterized by: In step S6, the top surface of the sealing adhesive is a flat inclined surface with an angle of 7 to 10 degrees.

4. The waterproofing process for the bottom edge plate of an oil tank according to claim 1 is characterized in that: The horizontal displacement mechanism comprises a base (15), bearing seats connected to both ends of the base, a screw rod (16) rotatably connected to the two bearing seats, a guide rod (17) connected to the two bearing seats, and a first motor (18) mounted on one end of the base, the first motor (18) being transmission-connected to the screw rod (16), the slide seat (1) being threadedly connected to the screw rod (16), and the slide seat (1) being slidably connected to the guide rod (17).

5. The waterproofing process for the bottom edge plate of an oil tank according to claim 4, characterized in that: The first driving mechanism comprises a second motor (19) mounted on a bracket, a first transmission shaft connected to the second motor via a coupling, a first main gear (20) connected to the first transmission shaft, and a first sub-gear (21) connected to the rotating shaft, wherein the first main gear (20) meshes with the first sub-gear (21).

6. The waterproofing process for the bottom edge plate of an oil tank according to claim 5, characterized in that: The glue injection gun comprises a gun body (22), a gun nozzle (23) connected to one end of the gun body, a glue inlet pipe (24) connected to the gun body, a piston (25) slidably arranged in the gun body, and a second cylinder (26) sealably mounted on one end of the gun body, wherein the second cylinder (26) is connected to the piston (25), and both sides of the gun body (22) are connected to hinge shafts, which are hinged to the L-shaped seat (8) through the hinge shafts, and the gun body (22) is mounted on the positioning plate (10).

7. The waterproofing process for the bottom edge plate of an oil tank according to claim 6, characterized in that: The second driving mechanism comprises a bearing plate (27) connected to the L-shaped seat, a third motor (28) arranged on the bearing plate, a second transmission shaft connected to the third motor via a coupling, a second main gear (29) connected to the second transmission shaft, and a second sub-gear (30) fixedly connected to one of the shafts, the second main gear (29) meshing with the second sub-gear (30).

8. The waterproofing process for the bottom edge plate of an oil tank according to claim 7, characterized in that: A fastening nut (39) is threadedly connected to the shaft rod (11) near the L-shaped seat, and the fastening nut (39) is screwed to press tightly against the L-shaped seat (8), so that the shaft rod (11) can be kept fixed.

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