Four steps for acceptance of jigs
When buying equipment and clamping jigs, we all hope that the final product we get is good and meets our requirements. How can we ensure this to the maximum? In addition to prior communication with the supplier in detail, the “acceptance” of the product is also crucial. Today, we will take the acceptance of the clamp jig as an example and discuss it together.
Since the acceptance work is so closely related to the quality of the final product, then how can we do a good job of acceptance of the fixture? According to our own work experience, the whole acceptance work can be roughly divided into four steps.
1）Make the inspection list for the fixture.
(2) get the fixture for the inspection of the product parameters.
3）After the inspection of the fixture, the fixture handover with the production department, and make the handover records.
(4) the use of fixtures into production after the tracking and feedback.
Then we will take the “heat sink” fixture as an example to see how these four steps are implemented respectively.
The first step: the production of fixture inspection list
As the name implies, the inspection list is what we need to inspect for this fixture, including dimensions, materials, etc. Some companies may have a general inspection list for fixture inspection. But for each different jig, should be refined for this type of jig inspection list, remove unnecessary items, add targeted inspection entries. This will ensure the most comprehensive inspection of all aspects of the fixture.
Although there is a common fixture inspection sheet for the items that need to be considered when assembling a heat sink.
So what should a good fixture inspection sheet contain? According to my own work experience, I believe that a complete fixture inspection sheet needs at least the following four aspects of content.
1, the fixture appearance inspection: this should be the most basic, the most intuitive inspection content. This aspect is actually obvious through visual inspection, such as whether the design is in accordance with the original style of the drawing; the wear and tear of the surface and the fastening method used between components.
2、Jig size inspection: After the first step of the appearance of the inspection, we should have a rough idea of the situation of the jig. Then the next natural part of the details of a more accurate inspection. For heat sink fixtures, the diameter of the pin through hole, the relative position of the crystal hole on the fixture, etc. can be considered as key dimensions. These visual inspection can not be done by precise inspection, must be used to measure tools (calipers, plug gauges, etc.) to ensure that the drawings given on the assembly drawings with the heatsink consistent or within tolerance.
3, the suitability of the jig inspection: after the key dimensions are inspected, then it is time to take the physical suitability of the experiment. After all, most of the jig design is still based on theoretical and empirical values. No matter how accurate the fixture design, there is no guarantee that the actual use of no problems. Therefore, it is necessary to carry out physical verification, and there is a certain number of times to ensure.
4, jig anti-dumbing, error-proof inspection: this part may be the most easily ignored point, but we can not ignore the aspects. Because the previous 3 parts of the verification, we have been only in accordance with “our design ideas”, “the correct way to assemble the heat sink” and so on to test our fixtures. But we never considered if we could use the fixture in some “wrong” way, it would work. If so, will the subsequent regular production bring unimaginable losses due to these wrong but operable situations? To prevent the release of this situation is the jig dummy-proofness. It is also a part that we should pay attention to when accepting the jig.
Step 2: Inspection for each parameter of the fixture
After getting the jig from the supplier, it is natural to check the items in the inspection list one by one.
(1) The whole inspection process requires the intervention of quality department personnel, because the engineers may only consider the process aspects when designing the fixture, without detailed analysis of the potential quality risks. And the engineers themselves will be involved in the fixture design and may make judgments based on their own subjective experience. Therefore, it is necessary to arrange quality-related personnel to participate in the inspection process together.
2) Each inspection item needs to be inspected accordingly, and 100% of all new fixtures are inspected.
For example: whether the surface is worn, the fixture number is available, such items can be completed by visual inspection. And such as through-hole diameter, height limit, etc., need to use plug gauge, calipers and other measuring tools for inspection.
Step 3: Do a good job with the production department to hand over the fixture, make a record
This step may seem very simple, it seems to be just the inspection of the completed jig to the production department on the line. But in fact, it is also very important, first of all, the finished inspection jig should be marked accordingly, such as: labeled with “inspected” label. When handing over to the production department, the completed inspection list should also be filed and organized to facilitate follow-up tracking.
Secondly, in addition to the above handover process, the use of fixtures in the process should also be added accordingly “without inspection of fixtures can not be used on line” provisions. To prevent the uninspected jigs into production, may cause the waste of time and rework.
The fourth step: clip jig into formal production after the tracking and feedback
Probably the vast majority of people think that in the third step, after the jig to the production department, the whole acceptance process is over. In fact, this is not enough, a complete acceptance process should be followed by tracking the use of the operation and feedback.
When the inspected fixtures are in use, deviations or problems occur. In addition to analyzing the fixture itself with the supplier, the inspection list should be updated again to check whether the defect is caused by the omission of a key dimension or a wrong inspection method, so as to prevent similar problems from happening again.