Successful Kiln Selection and Installation
Input from the ceramic manufacturer on many elements of a kiln manufacturing project is not only welcome, but absolutely necessary.
It is vital for ceramic manufacturers to be part of the kiln selection process to help ensure that all elements of often-complex kiln supply projects are successfully and harmoniously brought together. Today’s industrial ceramic kilns are manufactured for a variety of specialty firing regimes, meeting the needs of both continuous and batch processes for manufacturers of products such as sanitaryware, technical ceramics, electroporcelain, dinnerware, high-temperature refractories, flow control refractories, abrasives, fused silica, and vitrified clay pipe, among many others. All kiln users—whether they are contemplating tunnel, shuttle, roller, rotary, elevator or Carbell installations—can extract the maximum from their investment while setting a platform for consistency, reliability, superior performance, and ultimately, the best possible end product quality.
Collaboration is Key
Today more than ever, it is important to recognize that the ceramic manufacturer should be part of the solution provided by any reputable kiln designer and manufacturer. Their involvement helps ensure, among other things, that all the equipment being supplied (including ancillaries) is exactly appropriate for the intended process, the location and any fuel supplies, while also meeting potential future plans that the manufacturer may have.
Although this may seem self-evident, it is nevertheless true that some ceramic manufacturers have no particular inclination to work closely with their kiln manufacturer during the project period. On the contrary, they seem happy enough to sign off on an agreed design, fabrication and payment schedule; beyond that, they don’t really wish to otherwise get involved.
This is an inefficient and ineffective approach. All empirical evidence strongly demonstrates that the more heavily the ceramic manufacturer is involved from the very beginning, the more successful all outcomes will be.
Ceramic manufacturer input on many elements of a kiln project is not only welcome, but absolutely necessary to make sure that the best possible results are realized. Some examples of potential considerations are shown below:
- Plant layout
- Optimal control panel location
- Kiln car handling system sequence
- Shutdown mechanisms and protocols
- Alarm operation
- System tolerances
- Adequate door loading clearance
While close liaison on all of these points is crucial, many other factors could be included on this list. For example, a number of essential health and safety issues should be considered, including all parameters that apply during installation and commissioning. The entire protocol needs to be addressed and then agreed upon by the kiln manufacturer and the client in order for the best possible outcome to be achieved. Kiln builders typically have expertise and resources in this area, and technical cooperation is always welcome at this stage.
Avoiding Potential Failures
Leading kiln manufacturers often employ specific, non-proprietary methodologies for kiln and furnace design. One of these, known as failure mode effects analysis (FMEA), constitutes a useful approach. During a typical FMEA process, engineers from the relevant technical teams hold meetings on the topic at hand. They begin by considering the project’s principal requirements. Once the specifics are understood, they consider what could go wrong and then determine ways to prevent those problems.
During the kiln design process, FMEA is used to prevent future failures. Potential failures are ranked according to how serious the consequences are, how frequently they occur and how easily they can be detected. The purpose of the FMEA is to take actions to eliminate or reduce failures, beginning with the most important.
The careful analysis that is undertaken usually leads to many possible actions. Once agreed upon, the concepts and plans for execution are then taken forward as part of the project. FMEA is especially applicable when a product or application is new.
Valuable outcomes result when problem avoidance has been built into the project. It is also beneficial to continue with FMEA throughout the lifetime of the system.
Hazard and Operability Analysis
In most cases, it also useful to back up FMEA with hazard and operability analysis (HAZOP). This process involves a multi-disciplinary approach and is employed as a technique for identifying potential hazards in a system (e.g., risk of explosion), as well as operability problems that are likely to lead to non-conforming products. Part of the HAZOP concept entails a bottom-up approach, and its success relies on the close cooperation and knowledge transfer between various subject matter experts.
Internationally accepted standards apply to how team members conduct themselves, though in reality the HAZOP studies very seldom need to be assessed according to these benchmarks. With that said, a large number of variables often need to be considered (e.g., all of those concerning safety).
These studies and procedures gain increased importance in a variety of situations. For example, companies must demonstrate that they’ve undertaken a comprehensive risk analysis when obtaining the CE mark in the EU.
Computational Fluid Dynamics
As an adjunct to HAZOP studies, simulations can also be designed and carried out. One example includes exploiting the power of computational fluid dynamics (CFD). This numerical tool enables the simulation of complex phenomena such as fluid flow, heat transfer, mass transfer and chemical reaction.
Values for all the simulated variables (e.g., temperature, flow, concentration, velocity) can be obtained at any given point of the simulated domain. Proprietary CFD software can be used for process design and, crucially, to identify potential improvement areas—all of which benefits the ceramic manufacturer in the long run.
Testing is a crucial part of the fabrication process. Not only can the ceramic manufacturer get involved in this process, it is highly desirable that they do. In any “best industry practice” kiln fabrication plant, tests are carried out on smaller individual items (including equipment from third-party suppliers) through to the much more crucial elements in the system. This is time well spent when considering long-term performance and maintenance issues.
Some kiln manufacturers are able to conduct this suite of tests in-house, which can represent an advantage. It is possible to identify anything that requires modifying or correcting before the kiln is shipped, saving time in the field.
Final kiln acceptance is easier if an acceptance protocol has been agreed upon. If acceptance is not defined at an early stage of the project, expectations may not be aligned. Alternatively, the ceramic manufacturer may ask for performance criteria that the kiln was not originally designed for.
With set criteria and the involvement and monitoring role of the ceramic manufacturer, everything points toward a defined point at which the manufacturer can accept the kiln. When clear objectives are established, both parties can enjoy a smooth transition to kiln commissioning and full service.
For more information, contact the author at firstname.lastname@example.org.