A method for pouring epoxy resin on a main engine base of a ship

Abstract

The application discloses a kind of ship main engine base epoxy resin pouring method, it is related to shipbuilding technical field.The method is respectively coated with zinc-free epoxy primer on the contact surface of the epoxy resin pouring of main engine body base and main engine hull base, sets up inside and outside epoxy resin baffle on main engine hull base and forms pouring mold frame, pours epoxy resin into mold frame, removes baffle and installs foot bolt after solidification.Zinc-free epoxy primer is coated in advance in main engine factory and hull stage respectively, replaces traditional rust grease plus butter temporary protection scheme, only needs to wipe dust and isopropyl alcohol cleaning before pouring, eliminates repeated oil coating, oil removal, rust removal process, eliminates the safety hazard that worker operates below suspended main engine.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding technology, and specifically to a method for casting epoxy resin for a ship's main engine base. Background Technology

[0002] The epoxy resin casting surface of the main engine base is exposed to the workshop and slipway environment for a long time before the main engine is installed, making it extremely prone to rusting. The main engine base is usually coated with hard anti-rust grease for factory protection at the main engine manufacturing plant, while the main engine base pre-installed in the hull section stage is coated with anti-rust paint. The traditional epoxy resin casting process requires multiple cleaning treatments for the casting surfaces of the main engine base and the hull base before casting: first, the hard anti-rust grease is removed or the anti-rust paint is sanded off, then anti-rust grease is applied for temporary protection. After the main engine is in place, the shafting is polished, and it is close to casting, the grease is washed off with diesel, the rusted areas are sanded again, and finally, it is cleaned with solvents such as acetone or carbon tetrachloride before casting.

[0003] This process has several problems. From a procedural perspective, the same casting surface undergoes multiple repetitive steps, including applying rust-preventive oil, degreasing, applying grease, degreasing, rust removal, and cleaning. This results in high material consumption and labor input. Furthermore, cleaning the main unit's base requires suspending the main unit, which is lifted by the gantry crane, in the air, with workers operating below it, posing significant safety hazards. From a quality perspective, the interval between the main unit entering the cabin and the actual casting is relatively long. The grease-protected surface may still develop localized rust spots before casting, requiring further polishing. If the dust and residual solvent generated during polishing are not thoroughly removed, they will affect the adhesion strength between the epoxy resin and the metal substrate.

[0004] To address the aforementioned issues, the industry has undertaken several explorations. Chinese utility model patent CN204585135U discloses a press-fitting device, which focuses on mechanical press-fitting tooling and does not involve surface treatment processes for the casting surface. Chinese invention patent application CN115042125A discloses a press-fitting device and method for water-lubricated bearings in marine shafting, primarily targeting the press-fitting process of the bearings rather than the casting and molding of the main engine base pad. Chinese invention patent CN111498051B discloses an epoxy casting tooling and method for marine main engines, which uses angle steel, bolts, and clips to form a detachable baffle structure. A gap is reserved between the base and the wet oil pan to avoid thermal expansion collisions. This solution improves the fixing method of the casting baffle, but still uses traditional base surface cleaning processes and does not address the simplification of the rust prevention and cleaning process for the casting surface. Chinese invention patent CN103786835B discloses a method for manufacturing and installing non-metallic pads for mechanical equipment. It uses a modified epoxy resin casting material reinforced with short fibers, improving the pad material itself. However, the method for treating the metal substrate before casting remains the traditional grinding and cleaning. ITW Chockfast's official installation guide, Technical Bulletin No. 692B / 692D, allows a thin layer of inorganic zinc-rich or epoxy primer to be retained on the epoxy casting surface. However, this guide only provides a general permission and does not provide a complete technical solution regarding primer selection, film thickness control, construction techniques, and coordination with the entire casting process.

[0005] Therefore, there is a need for a method for epoxy resin casting of ship main engine base that can eliminate the need for repeated oiling, degreasing, and rust removal steps before casting, while ensuring the bonding quality between epoxy resin and metal substrate. Summary of the Invention

[0006] This invention solves the technical problems of existing technologies, such as the need for repeated oiling, degreasing, and rust removal on the casting surface, which leads to significant waste of labor and materials, and safety hazards for workers operating under the suspended main unit. It replaces the traditional method of applying zinc-free epoxy primer to the epoxy resin casting contact surfaces of the main unit base and the main unit hull base in advance, thus achieving the technical effect of only needing simple dust removal and degreasing before casting, reducing the number of processes and safety risks.

[0007] An embodiment of the present invention provides a method for epoxy resin casting of a ship's main engine base, comprising the following steps: applying zinc-free epoxy primer to the epoxy resin casting contact surfaces of the main engine body base and the main engine hull base respectively; setting an inner epoxy resin baffle and an outer epoxy resin baffle on the main engine hull base, the inner epoxy resin baffle, the outer epoxy resin baffle, the main engine body base, and the main engine hull base together forming a casting mold frame; casting epoxy resin into the casting mold frame, so that the epoxy resin fills the space between the main engine body base and the main engine hull base; after the epoxy resin has cured, removing the inner epoxy resin baffle and the outer epoxy resin baffle, and installing the base bolts.

[0008] Furthermore, the zinc-free epoxy primer is a polyamide-cured epoxy primer, composed of component A and component B mixed in a 4:1 volume ratio, with a volume solids content of 60±2% and a dry film thickness not exceeding 0.08 mm. This primer does not contain zinc powder, thus preventing zinc salt precipitation at the epoxy resin casting interface and ensuring adhesion. Simultaneously, the epoxy film-forming substance exhibits good compatibility with the epoxy resin used for casting.

[0009] Furthermore, before applying the zinc-free epoxy primer, the epoxy resin casting contact surface of the main engine hull base is manually sanded to Sa2.5 grade; the zinc-free epoxy primer is applied by spraying. The primer application of the main engine base is completed at the main engine manufacturing plant, eliminating the need for further lifting and cleaning after the main engine arrives at the plant.

[0010] Furthermore, the upper edge of the inner epoxy resin baffle is lower than the designed thickness of the epoxy resin, and the inner epoxy resin baffle is fixed to the main engine hull base by spot welding; the outer epoxy resin baffle is spaced apart from the bottom edge of the main engine base, the height of the outer epoxy resin baffle is higher than the thickness of the epoxy resin pad, the outer epoxy resin baffle is fixed to the main engine hull base by spot welding, and the surface of the outer epoxy resin baffle facing the inside of the casting mold frame is coated with a release agent.

[0011] Furthermore, sponge strips are filled between the inner epoxy resin baffle and the base of the main body; the inner epoxy resin baffle and the outer epoxy resin baffle are divided into blocks using sponge strips according to the epoxy resin pad block layout diagram.

[0012] Furthermore, where there are positions for adjusting bolts on the main engine hull base, clay is wrapped around the outside of the adjusting bolts and the base bolt hole pads; where there are no positions for adjusting bolts on the main engine hull base, sponge tubes with release agent coated on the outer surface are filled into the base bolt holes.

[0013] Furthermore, before pouring the epoxy resin, clean the dust from the pouring contact surface with a cloth and remove grease with isopropyl alcohol; when the ambient temperature is below 13°C, preheat the epoxy resin in a 25°C oven for 24 hours, and after adding the curing agent to the epoxy resin, stir at a speed of 500 rpm to 800 rpm for 1 to 3 minutes.

[0014] Furthermore, the epoxy resin flows freely into the casting mold frame in thin strips, and the height of the casting riser is not less than 15mm; during the curing period of the epoxy resin, it is prohibited to carry out hoisting of heavy objects, electric welding, grinding and water immersion operations in the vicinity.

[0015] Furthermore, after the epoxy resin has cured to a Barcol hardness of not less than 40, remove the adjusting bolts, sponge tube, sponge strip, and outer epoxy resin baffle.

[0016] Furthermore, when installing the anchor bolts, divide the anchor bolts into three parts: front, middle, and rear. Tighten them symmetrically from the middle to both sides with a tension of 1500 bar. Tighten them in two stages: the first time at 750 bar and the second time at 1500 bar. After tightening all the bolts in sequence, tighten the middle part again with 1500 bar.

[0017] The beneficial effects of this invention are as follows:

[0018] This invention pre-coats the epoxy resin casting contact surfaces of the main engine base and the main engine hull base with a zinc-free epoxy primer. The primer's inherent rust-preventive properties replace the traditional temporary protection solution of rust-preventive grease and tallow, simplifying the pre-casting cleaning process from multiple oiling, degreasing, and rust removal steps to a simple dust and grease removal. Simultaneously, the primer application is carried out at the main engine manufacturing plant, eliminating safety hazards for workers operating under the suspended main engine. The zinc-free epoxy primer, like the epoxy resin used for casting, belongs to the epoxy system and does not contain zinc powder, avoiding weak boundary layers caused by zinc salt precipitation and ensuring reliable adhesion between the pad and the metal substrate. Inner and outer baffles, along with sponge strips, putty, and sponge tubes, constitute a complete leak-proof casting mold frame. Combined with fine-flow casting and riser static pressure, the pad is densely filled. The entire process, from primer application, casting control, curing inspection to the symmetrical graded tightening of the anchor bolts, forms a closed-loop quality control chain, enabling stable construction under different ship types and seasonal conditions. Attached Figure Description

[0019] Figure 1 This is a schematic cross-sectional view of the casting state with the position of the adjustment bolt in an embodiment of the present invention;

[0020] Figure 2 This is a schematic cross-sectional view of the casting state without adjusting bolts in an embodiment of the present invention;

[0021] Figure 3 This is a cross-sectional view of the installation of the anchor bolts after the casting is completed in an embodiment of the present invention.

[0022] In the diagram, 1. Main engine base; 2. Main engine hull base; 3. Epoxy resin; 4. Inner epoxy resin baffle; 5. Outer epoxy resin baffle; 6. Sponge strip; 7. Adjusting bolt; 8. Anchor bolt hole pad; 9. Modeling clay; 10. Sponge tube; 11. Anchor bolt; 12. Hydraulic nut; 13. Bushing; 14. Spherical washer; 15. Spherical hydraulic nut; 16. Zinc-free epoxy primer. Detailed Implementation

[0023] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0024] The epoxy resin casting method for ship main engine bases proposed in this invention is applicable to the epoxy resin pad casting construction of main engines for various types of civilian ships such as bulk carriers and oil tankers. Figure 1 and Figure 2 As shown, the main unit base 1 is stacked on top of the main unit hull base 2, with a pre-reserved gap between them. Epoxy resin 3 fills the gap between the main unit base 1 and the main unit hull base 2 and forms a load-bearing pad after curing. Zinc-free epoxy primer 16 is applied to the epoxy resin casting contact surfaces of the main unit base 1 and the main unit hull base 2, respectively. The zinc-free epoxy primer 16 covers the bottom surface of the main unit base 1 where it contacts the epoxy resin 3 and the top surface of the main unit hull base 2 where it contacts the epoxy resin 3. The two layers of zinc-free epoxy primer 16 were applied and fully cured before casting.

[0025] The main engine base 1 is the main engine mount component shipped from the main engine manufacturer. Its epoxy resin casting contact surface is coated with a zinc-free epoxy primer 16 at the manufacturing plant. The technical agreement signed with the main engine manufacturer explicitly requires the manufacturer to apply a specified type of zinc-free epoxy primer 16, such as Jotacote Universal F60, to the epoxy casting surface of the main engine base 1. This primer is a polyamide-curing epoxy primer, with component A and component B mixed at a 4:1 volume ratio, a volume solids content of 60±2%, a density of approximately 1.4 kg / L, and a recommended film thickness range of 50 to 300 micrometers. When applied to the casting surface, the dry film thickness should be controlled within 0.08 mm. Since the primer is applied and cured at the main engine manufacturer, after the main engine is transported to the shipyard, the casting surface is completely protected by the cured epoxy film, eliminating the need for applying a hard anti-rust grease.

[0026] The casting surface of the main engine hull base 2 is coated with zinc-free epoxy primer 16 during the hull sectioning or slipway stages. Before application, the epoxy resin casting contact surface of the main engine hull base 2 is manually sanded to Sa2.5 grade, i.e., near-white metallic cleanliness, removing oxide scale, rust, and old coatings. After successful sanding, zinc-free epoxy primer 16 is applied by spraying. The nozzle diameter is selected from 0.019 inches to 0.031 inches (approximately 0.48 mm to 0.79 mm), with a minimum nozzle pressure of 150 bar. A single spray coat is applied, with a dry film thickness not exceeding 0.08 mm. The drying time varies with ambient temperature; surface drying takes approximately 2 hours at 23°C, and the drying time is correspondingly longer at lower temperatures. After the primer has fully cured, an appearance inspection and adhesion inspection shall be carried out. No pinholes, bubbles, cracks, runs, missed areas, peeling, undercoat bleeding, or particles are allowed on the surface. The dry film thickness shall be measured with a magnetic thickness gauge. 90% of the measuring points shall not be less than the design film thickness, and the remaining 10% of the measuring points shall not be less than 90% of the design film thickness. The adhesion shall be tested by the cross-cut test according to GB / T 9285 with 1mm squares and a rapid tearing method of the tape. A grade of 0 to 1 is considered qualified.

[0027] The selection of the zinc-free epoxy primer 16 is crucial to this method. Traditional processes allow the retention of an inorganic zinc-rich primer on the casting surface, but zinc powder may react with amine curing agents during epoxy resin curing to form zinc salts, creating a weak boundary layer at the metal-epoxy interface and affecting bond strength. The zinc-free epoxy primer 16 selected in this invention does not contain zinc powder, and its film-forming material is mainly composed of fatty acid-modified epoxy resin and polyamide curing agent. Chemically, it belongs to the same epoxy system as the epoxy resin used for casting, resulting in good interfacial compatibility. Simultaneously, the epoxy primer itself has excellent rust prevention capabilities; during the several weeks or even months between the main unit's entry into the tank and casting, no rust will reappear on the casting surface, eliminating the need for the traditional processes of applying grease for protection and re-grinding and rust removal before casting.

[0028] like Figure 1 As shown, at the location where the adjusting bolt 7 is located, a base bolt hole pad 8 is placed on the main engine hull base 2. The adjusting bolt 7 is screwed downwards from the main engine body base 1 and supported on the base bolt hole pad 8, used to adjust the height of the main engine and the alignment of the shaft system. A positioning step is provided below the base bolt hole pad 8 to fix the position of the pad. The outer diameter of the base bolt hole pad 8 is larger than the base bolt hole but smaller than the small diameter of the threaded hole on the main engine body base 1, so that it can be removed from above after casting. The adjusting bolt 7 and the base bolt hole pad 8 are wrapped with modeling clay 9. The outer diameter of the modeling clay 9 is 2mm to 3mm larger than the diameter of the base bolt hole pad 8, forming an isolation layer on the surface of the bolt and the pad. After the epoxy resin 3 cures, it will not adhere to the bolt and the pad, making it easy to unscrew the adjusting bolt 7 and remove the base bolt hole pad 8.

[0029] like Figure 2As shown, in locations where the adjusting bolts 7 are not installed, sponge tubes 10 are inserted into the bolt holes of the main engine hull base 2. The outer surface of the sponge tubes 10 is coated with a release agent. The sponge tubes 10 completely fill the bolt holes, preventing epoxy resin 3 from leaking out during casting. After the release agent is applied and cured, the sponge tubes 10 are easily removed as a whole. This method of using putty to wrap the holes and sponge tubes to seal them, depending on whether adjusting bolts are present, ensures reliable sealing of bolt holes in different locations during casting.

[0030] The inner epoxy resin baffle 4 and the outer epoxy resin baffle 5 are installed in place before casting. The inner epoxy resin baffle 4 and the outer epoxy resin baffle 5, together with the main engine body base 1 and the main engine hull base 2, form the casting mold frame. The inner epoxy resin baffle 4 is located near the centerline of the hull and is made of flat steel with a thickness of about 8mm, and is fixed to the main engine hull base 2 by spot welding. The upper edge of the inner epoxy resin baffle 4 is 10mm to 15mm lower than the design thickness of the epoxy resin. This height difference allows for the adjustment of the shaft system during the main engine installation, so that the adjusting bolt 7 still has some downward adjustment space. The outer epoxy resin baffle 5 is located near the outer plate of the hull and is also made of steel plate with a thickness of about 8mm, and is fixed to the main engine hull base 2 by spot welding. The outer epoxy resin baffle 5 is 15mm to 25mm away from the bottom edge of the base 1 of the main body. Its height is 20mm to 40mm higher than the thickness of the epoxy resin pad. The higher part forms a pouring riser. When pouring, the epoxy resin liquid level is higher than the thickness of the pad. Static pressure is used to ensure that the bottom of the pad is filled tightly.

[0031] A sponge strip 6 is used to fill the gap between the inner epoxy resin baffle 4 and the main body base 1. The sponge strip 6 is 20mm thick and its height is 3mm to 6mm greater than the thickness of the epoxy resin. It fills the gap by compression to prevent the epoxy resin 3 from leaking from the inside. The joint between the inner epoxy resin baffle 4 and the main body base 2, as well as the spot weld gap between the outer epoxy resin baffle 5 and the main body base 2, are sealed with putty 9. The surface of the outer epoxy resin baffle 5 facing the inside of the casting mold frame is coated with a release agent to facilitate the removal of the baffle after curing without damaging the side of the pad.

[0032] When the main unit base requires multiple independent spacers along the longitudinal direction, the inner epoxy resin baffle 4 and the outer epoxy resin baffle 5 are divided into sections using sponge strips 6 according to the epoxy resin spacer layout diagram. The sponge strips 6 used for sectioning are also 20mm thick, but their height is 3mm to 6mm greater than the epoxy resin thickness. This divides the entire casting area into several independent casting units, with each unit corresponding to a spacer position. This facilitates control over the casting quality of each spacer and prevents uneven shrinkage during large-area casting.

[0033] The pre-casting cleaning process is significantly simplified. Since the casting surfaces of both the main engine base 1 and the main engine hull base 2 are protected by zinc-free epoxy primer 16, preventing rust, only a clean cloth is needed to wipe away surface dust before casting, followed by isopropyl alcohol to remove any remaining grease. Compared to traditional processes, this eliminates steps such as cleaning grease with diesel fuel, sanding to remove rust, and cleaning with acetone or carbon tetrachloride, and workers no longer need to work under the suspended main engine. The zinc-free epoxy primer 16 on the main engine base 1 is applied at the main engine manufacturing plant, a crucial step in simplifying the pre-casting cleaning process at the shipyard.

[0034] The pouring of epoxy resin 3 is significantly affected by ambient temperature. When the ambient temperature is below 13℃, the viscosity of the epoxy resin increases significantly, making it difficult to stir and flow. In this case, the epoxy resin container should be placed in an insulated box set at 25℃ for preheating and kept at that temperature for 24 hours to raise the material temperature to a suitable range for construction. The optimal ambient temperature for pouring is 20℃ to 25℃. When adding the hardener to the epoxy resin, the amount of hardener added should be determined based on the temperature of the steel plate and the thickness of the epoxy resin pad. The stirring blade should be mounted on a stirring drill and stirred at a speed of 500 rpm to 800 rpm for 1 to 3 minutes. During stirring, the blade should always be submerged below the surface of the resin to avoid air entrapment.

[0035] After thorough mixing, pour immediately. Epoxy resin 3 should flow freely into the casting mold in thin streams, starting from the lowest point of the gating gate, filling all parts of the mold naturally. This thin stream pouring avoids introducing air into the resin. Discard any resin remaining at the bottom of the container to prevent uneven mixing from affecting curing quality. The liquid level at the gating riser should be at least 15mm to ensure that the spacer fills the entire gap after resin shrinkage during curing.

[0036] The curing time of epoxy resin 3 varies with temperature: approximately 48 hours at 13℃ to 17℃, approximately 26 hours at 18℃ to 20℃, approximately 24 hours at 21℃ to 25℃, approximately 18 hours at 26℃ to 31℃, and approximately 12 hours at 32℃ to 35℃. It cannot cure properly below 13℃. During the curing period, no heavy lifting, welding, grinding, or immersion in water should be carried out around the pouring area to avoid vibration, heat, and water affecting the curing reaction and bonding quality of the epoxy resin. Once the epoxy resin 3 has cured to a Barcol hardness of 24 or higher, the outer epoxy resin baffle 5 can be removed and its sharp edges trimmed. When removing the baffle, do not use a hammer to strike it, as this may cause cracks in the pad. Use a grinder or cutter to carefully cut the weld points. For final inspection, the Barcol hardness should not be less than 40, and the surface of the pad should be free of cracks or pores.

[0037] like Figure 3As shown, after the hardness test is passed, the baffle is removed and the base bolts 11 are installed. The adjusting bolts 7 and the base bolt hole washers 8 are removed, the sponge tubes 10 are pulled out, and the sponge strips 6 and modeling clay 9 are removed. The base bolts 11 are then inserted into the bolt holes of the main engine body base 1 and the main engine hull base 2. Bushings 13 and hydraulic nuts 12 are sequentially fitted onto the bolts on one side of the main engine body base 1. Spherical washers 14 and spherical hydraulic nuts 15 are installed on one side of the main engine hull base 2. The mating surfaces of the spherical washers 14 and spherical hydraulic nuts 15 can automatically adapt to the slight angular deviation of the hull base. The base bolts 11 are tightened using a hydraulic tensioner. All the base bolts 11 are divided into three parts according to their position: front, middle, and rear. They are tightened symmetrically from the middle to both sides. The tensioning is performed in two stages: the first tensioning pressure is 750 bar, and the second is 1500 bar. After all the bolts are tightened in sequence, the middle part is re-tensioned at 1500 bar to eliminate the prestress loss caused by the sequential tightening.

[0038] The method of this invention has been implemented on various ship types, including 63,600-ton bulk carriers and 154,000-ton shuttle tankers. Each ship can save on material costs such as grease, diesel, and rust-preventive grease, as well as labor costs. Moving the main engine base primer application to the main engine plant also saves time spent on gantry cranes and eliminates the safety risks associated with cleaning work under the suspended main engine. According to the technical requirements of the epoxy resin manufacturer, the zinc-free epoxy primer 16 can also be selected from zinc-free epoxy primers such as CMP BANNNOH 1500, Nippon E-Marine A / E, or PPG Sigmacover 380, as long as its film-forming substance is compatible with the epoxy resin used for casting and the film thickness is controlled within 0.08mm. The cross-sectional dimensions of the sponge strip 6 and sponge tube 10 can be appropriately adjusted according to the gap between the pads and the diameter of the bolt holes. The epoxy resin 3 can be selected from casting-type epoxy resins approved by classification societies, such as Polypad Super Chock or Chockfast Orange, according to the requirements of the shipyard and shipowner.

Claims

1. A method for casting epoxy resin for a marine main engine base, characterized in that, Includes the following steps: Zinc-free epoxy primer is applied to the epoxy resin casting contact surfaces of the main engine body base and the main engine hull base. An inner epoxy resin baffle and an outer epoxy resin baffle are installed on the main engine hull base, and the inner and outer epoxy resin baffles together with the main engine body base and the main engine hull base form a casting mold frame. Epoxy resin is poured into the casting mold frame to fill the space between the main engine body base and the main engine hull base. After the epoxy resin has cured, the inner and outer epoxy resin baffles are removed, and the base bolts are installed.

2. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, The zinc-free epoxy primer is a polyamide-cured epoxy primer, which is made by mixing component A and component B in a volume ratio of 4:1, with a volume solids content of 60±2% and a dry film thickness of no more than 0.08mm.

3. The epoxy resin casting method for the ship's main engine base according to claim 2, characterized in that, Before applying the zinc-free epoxy primer, the epoxy resin casting contact surface of the main engine hull base is manually sanded to Sa2.5 level; the zinc-free epoxy primer is applied by spraying.

4. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, The upper edge of the inner epoxy resin baffle is lower than the designed thickness of the epoxy resin, and the inner epoxy resin baffle is fixed to the main body hull base by spot welding; the outer epoxy resin baffle is spaced apart from the bottom edge of the main body base, the height of the outer epoxy resin baffle is higher than the thickness of the epoxy resin pad, the outer epoxy resin baffle is fixed to the main body hull base by spot welding, and the surface of the outer epoxy resin baffle facing the inside of the casting mold frame is coated with a release agent.

5. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, The space between the inner epoxy resin baffle and the base of the main body is filled with sponge strips; the space between the inner epoxy resin baffle and the outer epoxy resin baffle is divided into blocks by sponge strips according to the epoxy resin pad block layout diagram.

6. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, The main engine hull base has positions for adjustment bolts, and modeling clay is wrapped around the outside of the adjustment bolts and the base bolt hole pads; where there are no adjustment bolt positions on the main engine hull base, sponge tubes with release agent coated on the outer surface are filled into the base bolt holes.

7. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, Before pouring epoxy resin, clean the dust from the pouring contact surface with a cloth and remove grease with isopropyl alcohol. When the ambient temperature is below 13℃, preheat the epoxy resin in a 25℃ oven for 24 hours. After adding the curing agent to the epoxy resin, stir at a speed of 500rpm to 800rpm for 1 to 3 minutes.

8. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, Epoxy resin flows freely into the casting mold frame in thin strips, and the height of the casting riser is not less than 15mm. During the curing period of epoxy resin, it is forbidden to carry out hoisting of heavy objects, electric welding, grinding and water immersion operations in the surrounding area.

9. The epoxy resin casting method for the marine main engine base according to claim 1, characterized in that, After the epoxy resin has cured to a Barcol hardness of not less than 40, remove the adjusting bolts, sponge tube, sponge strip and outer epoxy resin baffle.

10. The epoxy resin casting method for the ship's main engine base according to claim 1, characterized in that, When installing the anchor bolts, divide the anchor bolts into three parts: front, middle, and back. Tighten them symmetrically from the middle to both sides with a tension of 1500 bar. Tighten them in two stages: the first time at 750 bar and the second time at 1500 bar. After tightening all the bolts in sequence, tighten the middle part again at 1500 bar.

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