How to write equipment specifications (be a designer)
In this article, I'll talk about the theme of "How to write equipment specifications". In my experience as a production engineer, I often have to prepare equipment specifications and order equipment for mass production. In this article, I will outline the equipment specifications and introduce the key points for writing equipment specifications.
【contents】
- What is equipment specification?
- How to write a equipment specification
- Common mistakes in creating equipment specifications
- How to verify equipment specifications
- Reference and Guide
What is equipment specification?
When you become a production engineer, you may have to install mass production line in your plant.
This may be a capital investment on the scale of entire production line, or on the level of a single unit of equipment. Some companies have their own in-house equipment manufacturing department that prepares the necessary equipment, but in most cases, the equipment is ordered to external supplier.
In any case, we prepare the equipment specification sheet first.
This equipment specification sheet is a document that indicates what kind of equipment you want to make. For example, it includes the following items.
- The size of the equipment should be less than or equal to ×××× ( To fit the layout.)
- equipment should judge ××× , and each standard shall be specified as ××××.
- required cycle time shall be less than or equal to ××××.
- structure of the jig shall be as shown in ××××.
- For the positioning, use the part shown in the ××××.
I have seen many equipment specifications and equipment, but on very few occasions I have seen a worthy equipment specification. Poorly completed equipment specifications can result in many additional meetings and multiple questions after the equipment has been ordered.
This approach results in a negative effect on the perfection of the equipment.
Even if the equipment is good, it is only because the equipment supplier is excellent. If you order a different supplier, it will not be repeatable. As a production engineer, this is a situation to be avoided. Essentially, all the necessary items should be in the document.
How to write a equipment specification
So what equipment specifications should you prepare?
The idea is simple. Write them as if you were designing and building the equipment. When we think about how to design the mechanical, electrical, and software aspects of the structure, the necessary points come naturally to mind.
In the case of mechanical design, the overall framework is determined once the overall rigidity and structure, positioning parts, components to be used, strokes and outputs, and overall size of the equipment are determined. In the case of electrical and software design, the overall framework is also determined by determining the data input items, accuracy, safety specifications, interfaces and input/output.
Anyone who has built their own equipment or who has experienced difficulties in installing equipment can imagine the above from a designer's perspective. Someone who has never built such a equipment, or who has never struggled with installing equipment, cannot write a complete equipment specification.
Common mistakes in creating equipment specifications
Although not recommended, it is common to imitate the equipment specifications of similar equipment. This is much more efficient than creating from zero, but this would depend on the quality of previous equipment specifications. If past equipment specifications are lazy specifications, then ordering equipment based on those specifications will not result in good equipment. The quality of past equipment does not always match the quality of its equipment specifications.
How to verify equipment specifications
So, how can you objectively determine if the equipment specifications are sufficient? This is also easy. You should be able to determine whether you can design the equipment yourself or not, based on that equipment specifications. You can't design a equipment with such empty specification.
Reference and Guide
When preparing the equipment specifications, the specifications of similar equipment should be used as a reference. (Step 1)
If the content is excellent, you can follow the equipment specifications. If there are many missing contents, refer to the equipment drawings rather than the equipment specifications. (Step 2)
Mechanical drawings and electrical wiring diagrams will help you understand the equipment structure and control methods. If you are an inexperienced engineer, you can summarize the details in the equipment specifications based on that structure. If you are experienced, you will arrange your own decisions.
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