Pre-shipment Quality Inspection for 1,500W LED Stadium Lights

How can we find out the serious problem and preliminarily analyze the causes?

Recently, on September 26, 2022, we did a pre-shipment inspection for LED stadium lights of high power 1,000W – 1,500W on behalf of a foreign lighting purchaser.

Unfortunately, we found a major quality problem during the inspection (Below, we will introduce the phenomenon, consequences, and causes of this quality problem). So, we drew a conclusion as Fail in the Pre-shipment Inspection Report, and immediately notified the supplier and the buyer.

The following is a phenomenon that the BackMorning inspector found for the quality issue.

• So, what is this quality problem?
• How is it found?
• And what will be the consequences?

Quality problem description:

During the inflatable test of LED stadium lights, the BackMorning inspector found that there were bubbles coming out, so he concluded the result as disqualified.

The consequence of this problem:

The stadium lights will be seriously waterlogged after a period of time, thus making the lights fail. (Remark: The after-sales cost for such a large light is very high, and it can damage the purchaser’s brand. So, the quality must be highly reliable).

Potential causes:

The detailed causes will need 8D analysis, and we cannot draw conclusions for the time being.
According to our experience, I think it can be these causes.

1. Problems caused by die-casting: These lights’ shells are made from aluminum die-casting, there might be some excessively long sand eyes in the process of die-casting.
2. Machining errors on the lights’ bodies – Workers need to make screw holes in the die-casting light bodies, and the screw holes penetrate the bodies of the lights.
3. It may also be caused by the combination of the two problems 1 and 2.

Test method of BackMorning:

Soak the light body into the water, and then use the airtightness test instrument to inflate its body.
In fact, BackMorning also found that the light body itself had water leakage in the previous inspection of LED floodlights’ housings, because the screw hole penetrated the light body.

These LED stadium lights must be shipped before China’s National Day (10.1). So, after we found the problem, the supplier made an emergency repair for all the lights (replace the housings). And our inspector also worked overnight until 3 am. After verifying the quality of the lights to be qualified, then he reported to the buyer and approved the shipment.

(Remark: China’s National Day has a 7-day legal holiday, so if the lights can’t be shipped before National Day, the shipment of all the LED stadium lights will be delayed for more than 7 days. Therefore, before every Chinese National Day, there will be many shipments shipped in advance.)