Meat growing process of main hull pile fixing chamber cylinder plate

Abstract

The invention relates to the technical field of ocean engineering, in particular to a main hull pile fixing chamber barrel plate growing process which comprises the following steps that S1, oil stains, oxide skin, rust and other substances harmful to welding within the range of 20 mm on the outer surfaces of barrel plates on the two sides of a welding bead are cleaned; s2, the long meat part is made into a groove shape, so that the long meat part exposes metallic luster; s3, pasting a ceramic liner on the back surface of the cylinder plate; s4, carrying out long meat preheating treatment; s5, the preheating temperature and the interlayer temperature are measured through a point temperature meter; s6, multi-layer and multi-pass welding is adopted for welding, and it needs to be ensured that joints are staggered and cannot be stacked together; s7, removing a ceramic liner, and back-sealing welding after back gouging; s8, after welding is finished, heat preservation cotton is immediately used for covering for heat preservation and slow cooling; and S9, after slow cooling is finished for 48 h, 100% MT + UT 100% flaw detection is carried out, and 100% MT + UT 100% scanning is needed again after the long meat part is rounded. The stress of the welding joint can be eliminated, and the breaking load, tensile strength, deflection and other mechanical properties of the welding joint are enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of marine engineering, and in particular to a process for growing a cylinder plate of a main hull pile fixing chamber. Background Art

[0002] With the increasing shortage of energy and the increasing shortage of land resources for wind farms, offshore wind power generation has become a new development direction for wind power generation in the world today. The installation of offshore wind turbines is more technically difficult than that of onshore wind turbines. The manufacture of offshore installation platforms is one of the key technologies for realizing the construction of offshore wind farms.

[0003] When cutting the cylinder of the hull pile fixing chamber, no process allowance is added and it is cut according to the net size of the cylinder diameter. In order to ensure that the final finished size of the cylinder is within the positive tolerance, the cylinder needs to be lengthened. Summary of the invention

[0004] The purpose of the present invention is to provide a main hull pile chamber cylinder plate lengthening process to address the defects of the prior art, so as to ensure that the final finished size of the cylinder is the positive working difference, so that the enlarged gap does not exceed 25mm.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A main hull pile fixing chamber cylinder plate growth process, comprising the following steps:

[0007] S1. Clean the oil, scale, rust and other substances harmful to welding within 20mm of the outer surface of the cylinder plate on both sides of the weld;

[0008] S2, making the long flesh part into a groove shape to reveal its metallic luster;

[0009] S3, paste the ceramic liner on the back of the cylinder plate;

[0010] S4, preheating the long meat;

[0011] S5. Use a spot thermometer to measure the preheating temperature and interlayer temperature;

[0012] S6. When welding with multiple layers and multiple passes, ensure that the joints are staggered and not overlapped;

[0013] S7, remove the ceramic liner, clean the root and weld the bottom;

[0014] S8. After welding, immediately cover with thermal insulation cotton to keep warm and slow down cooling;

[0015] S9. Carry out 100% MT+UT100% flaw detection 48 hours after the slow cooling. After the long meat area returns to roundness, it needs to be scanned again with 100% MT+UT100%.

[0016] As a preferred technical solution of the present invention, the preheating temperature in the step S4 is 70-80°C, and the temperature during the welding process is controlled at 150-200°C.

[0017] As a preferred technical solution of the present invention, the distance between the measuring points in step S5 is 50-100 mm from the center of the weld.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention can eliminate the stress of the welding joint, enhance the mechanical properties of the welding joint such as breaking load, tensile strength, deflection, etc., make the welding quality more stable, and can effectively reduce the welding stress inside the welding joint by using thermal insulation cotton for insulation and slowly cooling to room temperature, thereby ensuring that the final finished size of the cylinder is the positive working difference, so that the enlarged gap does not exceed 25mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the long meat groove in the present invention;

[0021] Figure 2 It is a structural schematic diagram of the double-sided groove in the present invention; DETAILED DESCRIPTION

[0022] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0023] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] Example

[0025] The present invention provides a main hull pile chamber cylinder plate growth process, referring to Figure 1-2 As shown, the following steps are included:

[0026] S1. Clean the oil, scale, rust and other substances harmful to welding within 20mm of the outer surface of the cylinder plate on both sides of the weld;

[0027] S2, making the long flesh part into a groove shape to reveal its metallic luster;

[0028] S3, paste the ceramic liner on the back of the cylinder plate;

[0029] S4, preheating the long meat;

[0030] S5. Use a spot thermometer to measure the preheating temperature and interlayer temperature;

[0031] S6. When welding with multiple layers and multiple passes, ensure that the joints are staggered and not overlapped;

[0032] S7, remove the ceramic liner, clean the root and weld the bottom;

[0033] S8. After welding, immediately cover with thermal insulation cotton to keep warm and slow down cooling;

[0034] S9. Carry out 100% MT+UT100% flaw detection 48 hours after the slow cooling. After the long meat area returns to roundness, it needs to be scanned again with 100% MT+UT100%.

[0035] Wherein, the preheating temperature in the step S4 is 70-80°C, and the temperature during the welding process is controlled at 150-200°C.

[0036] Wherein, in the step S5, the distance between the measuring points and the weld center is 50-100 mm.

[0037] The welding material is flux-cored wire AWS 5.20E71T-1C / / 3YSH10.

[0038] CO2 gas shielded welding is used for welding. The welding parameters are as follows:

[0039] Welding layers Welding current (A) Welding voltage(V) Welding speed (mm / min) 1 180～200 24～26 220～250 2 200～220 25～27 250～300 3 200～220 25～27 250～300

[0040] refer to Figure 1 For the long groove, a steel plate with a material of DH36 and a thickness of 30 mm is selected to form the shape before welding as shown in the figure (a = 11 mm);

[0041] The welding method should adopt low current, slow welding speed and multi-layer and multi-pass welding, and keep warm and cool slowly after welding;

[0042] When welding is finished, the arc should be slowly extended to fill the arc crater to prevent the formation of arc crater cracks;

[0043] When using multi-layer and multi-pass welding, it is necessary to ensure that the joints are staggered and not overlapped;

[0044] Weld area UT100%+MT100%;

[0045] After NDT is qualified, the extended meat is cut with a semi-automatic cutting machine (length of extended meat = 11mm) and polished until it is the same as the parent material;

[0046] refer to Figure 2 The double-sided groove shown is welded normally using SAW without leaving any gap according to WPS requirements;

[0047] It should be noted that there should be no defects such as pores, slag inclusions, weld nodules, cracks, etc. in the long meat area, and the appearance should be uniform and no different from the parent material.

[0048] The present invention can eliminate the stress of the welding joint, enhance the mechanical properties of the welding joint such as breaking load, tensile strength, deflection, etc., make the welding quality more stable, and can effectively reduce the welding stress inside the welding joint by using thermal insulation cotton for insulation and slowly cooling to room temperature, thereby ensuring that the final finished size of the cylinder is the positive working difference, so that the enlarged gap does not exceed 25mm.

[0049] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A process for growing the main hull pile chamber cylinder plate, characterized in that: The steps include: S1. Clean the oil, scale, rust and other substances harmful to welding within 20mm of the outer surface of the cylinder plate on both sides of the weld; S2, making the long flesh part into a groove shape to reveal its metallic luster; S3, paste the ceramic liner on the back of the cylinder plate; S4, preheating the long meat; S5. Use a spot thermometer to measure the preheating temperature and interlayer temperature; S6. When welding with multiple layers and multiple passes, ensure that the joints are staggered and not overlapped; S7, remove the ceramic liner, clean the root and weld the bottom; S8. After welding, immediately cover with thermal insulation cotton to keep warm and slow down cooling; S9. Carry out 100% MT+UT100% flaw detection 48 hours after the slow cooling. After the long meat area returns to roundness, it needs to be scanned again with 100% MT+UT100%.

2. The process for growing the main hull pile chamber cylinder plate according to claim 1 is characterized by: The preheating temperature in step S4 is 70-80°C, and the temperature during the welding process is controlled at 150-200°C.

3. The process for growing the main hull pile chamber cylinder plate according to claim 1 is characterized by: In the step S5, the distance between the measuring points and the weld center is 50-100 mm.

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