October 2008 Issue
This month, I would like to discuss a small portion of the different processes that take place while working inside a fabrication facility. The focus will be on the fabrication of a heat exchanger, which is a vessel used to heat or cool various products in processing plants. Other areas that will be focused on are planning, teamwork and rewards that come from this career.
Planning is a proactive measure taken to help complete the job in a safe manner. Safety and quality are very important as a project is being assessed. Part of the planning process is the assignment of more detailed tasks to experienced colleagues. In turn, they will mentor the new fabricators on all of the necessary steps it takes to complete different tasks in a safe and successful manner. Sometimes, the experienced people will even go from one job to another, helping with team efforts, so colleagues can achieve success.
Teamwork cannot be overlooked while building vessels, as it takes a variety of groups to make the end product come together properly. One of the attributes about our team of heat exchanger builders is that they get along great, which helps in continuing a positive forward progression on projects.
What makes a fabrication career so interesting is how the process moves from start to finish. With regard to the fabrication of a heat exchanger, step one begins with a sheet of flat steel or a cylinder of steel. The flat sheet is cut to a specific size in a machine called a shear. The piece is then rolled into a cylinder shape causing each end of the steel to come togetherwhere a closure seam is tacked and welded. Finally, after several cylinders are rolled, they are connected to make one long cylinder and the closure seams are welded on the inside of the vessel. Layout of the vessel now begins.
The ability to read blue prints and lay out the overall dimensions of a heat exchanger is very important to the building process . If the tank is not properly marked for the appropriate orientation, the internal parts, which include tubes and baffles, will not line up in a correct manner. The external nozzles are also critical during this stage as they must match up with the necessary piping in the field upon delivery to the plants where they will be installed. Once the layout procedure is complete, it is checked by a quality control inspector and, after approval, all of the parts are installed on the inside and outside of the vessel. This is when the most welding takes place.
Welding is necessary to set the internal and external equipment. Colleagues use MIG welders to tack parts in place. Once everything is fit in the proper location, all of the external items are then welded solid. The steps taken during the fabrication process are completed using a combined team effort, including a good positive attitude and the sharing of knowledge and ideas.
The Fabrication and welding of heat exchangers is a very rewarding career. There are a variety of challenges faced during the process. However, with a strong supportive team, they become easy to break through. A great sense of accomplishment comes to the fabricator upon completion of the task since the bulk of the project is hand crafted - a lost art.