Fabrication is the initial stage of manufacturing. The fabrication process is carried out in a workshop that produces components for hull construction. The plate and profile material that enters the fabrication workshop is first blasted to remove the mill scale layer on the material layer. After blasting, the material is primed (shop primer) with a thickness of 18-25 micrometres so that it is not damaged in the process.
Fabrication. This paint protects the material from corrosion and lasts between 3-12 months (temporary). For the blasting work and primary shop under the supervision
paint workshop. After being blasted and who can only process the direct shop in the fabrication workshop?
The fabrication process consists of straightening, marking, cutting, and forming. Before the process is carried out, first identify the material that has been classified and check the number plate with the list contained in that class. After being placed, the classification bureau will sign the plate inspection.
Material working process:
1. Straightening
In transporting both plates and profiles from the factory or the material storage warehouse, sometimes deformation or bending occurs due to collisions or other things. This will complicate the marking and cutting process. It can
cause a lack of accuracy in marking and cutting. A rolling machine can pressure the deformed or bent parts to straighten the plate. While the profile uses a bending engine.
2. Marking
After the material is processed, the marker must match the plate and profile to be marked. If appropriate, the marking process can be carried out.
3. Cutting
This process is the cutting of materials that have gone through a marking process. What can be cut if the marking is approved by QA (quality assurance)? Many factors affect the cutting results in the cutting process, for example, the operator. Operator skill plays an important role in determining the quality of the cut. This is very visible in the manual cutting process (brander). Another influencing factor is the cutting accuracy of the machine. If the results of the cutting process are less smooth, then smoothing is done with a grinder. Most of the results from each cutting process are ground so that the next cycle is easier and faster. Then the material resulting from the cutting process, if it requires forming (curved parts), is immediately carried out by bending, rolling, or fairing.
Materials not requiring forming go straight into the assembly shop to be processed with other components. This process is called the sub-assembly process.
4. Forming
Many parts of the ship are in the form of arches. Therefore, the forming process is necessary for shipbuilding. Based on the work process, the forming process is divided into 2 (two) types, namely mechanical forming and thermal forming. Mechanical forming
The process that is often carried out is the formation of the hull skin and the formation of the frame. Thermal forming is a process carried out to create three-dimensional shapes or refine the form of the plates made
by bending with a bending machine or roll machine. This process requires sufficient expertise and skills because there is no standard method in the work process. This fabrication workshop will produce the components used in the sub-assemblies in the assembly workshop.
D. Components, Parts, and Assemblies
After fabrication is complete, it's time to assemble the parts. The job is done at the assembly workplace, and it consists of three primary steps:
• Sub-assemblies
The term "sub assembly" refers to breaking down large batches of fabrication-shop items into more manageable chunks (assembly parts). Plates with straight (parallel) or non-parallel cuts, curved plates, and other components like pipe pieces are still included. Combinations of bulkhead assembly, web frame assembly, and plate-with-plate construction are all examples of sub-assembly procedures.
"assembly" refers to putting together a whole from its component pieces. The number of blocks constructed is determined by the crane's lifting capacity.
E. Erections
Erection refers to joining the ship's ring block to form a single structure. Construction docks are the typical locale for erection work. Keel laying is the first step in the erection process, followed by joining the blocks to the ship's superstructure.
