26,000 3-inch photomultiplier tubes (PMTs) have been produced for Jiangmen Underground Neutrino Observatory (JUNO) by the Hainan Zhanchuang Photonics Technology Co., Ltd (HZC) company in China and passed all acceptance tests with only 15 tubes rejected. The mass production began in 2018 and elapsed for about 2 years at a rate of $\sim$1,000 PMTs per month. The characterization of the PMTs was performed in the factory concurrently with production as a joint effort between HZC and JUNO. Fifteen performance parameters were tracked at different sampling rates, and novel working strategies were implemented to improve quality assurance. This constitutes the largest sample of 3-inch PMTs ever produced and studied in detail to date.

海南展创光电子技术有限公司（HZC）为江门地下中微子观测台（JUNO）生产了26,000个3英寸光电倍增管（PMT），并通过了所有验收测试，只有15根被拒绝。大规模生产始于2018年，经过约2年的发展速度$〜$每月1,000 PMT。在HZC和JUNO的共同努力下，PMT的表征是在工厂与生产同时进行的。在不同的采样率下跟踪了15个性能参数，并采用了新颖的工作策略来提高质量保证。这构成了迄今为止生产和详细研究过的最大的3英寸PMT样品。