Quality

Witness point

(1) the construction unit shall, at a certain time before arriving at a witness point, notify the supervision engineer in writing, indicating the time when the witness point will be ready for construction, and the supervision personnel shall witness and supervise the site at that time.

(2) after receiving the notice, the supervision engineer shall indicate the date of receiving the notice and sign on the "construction tracking file".

(3) supervisors shall witness the scene at the agreed time. Supervision personnel shall supervise and inspect the implementation process of witness points and sign after making detailed records on the witness form.

(4) if the supervisor fails to be present at the specified time, the construction unit may consider that it has been approved by the supervision engineer and has the right to carry out the construction.

(5) if the supervisor has been to the site for inspection before this time and has written the relevant opinions on the "construction tracking file", the construction unit shall indicate the improvement measures taken or specific opinions.

Process control

1. The position of quality control in the production process in product quality control. Since 1990s, great changes have taken place in the quality control theory. Modern quality engineering technology divides the quality control into several stages. The quality control in the stage of product development and design is called quality design. In manufacturing, the process of production needs to be monitored. This stage is called the quality control stage.

Quality control by sampling inspection is the traditional quality control, which is called post - event quality control. In the above several stages the most important is the quality design, the second is the quality control, and the third is the quality control after the event. For those production processes with low quality level, post-mortem inspection is indispensable, but quality control should be source control, prevention as early as possible. Post-mortem control should be phased out. Indeed, firms in some rich countries have abolished post-mortem checks. To sum up, process monitoring is the key to quality control at the source of product quality.

2. To ensure product quality, it is necessary to strengthen the quality control of the production process. Quality control is the operation techniques and activities taken to achieve the quality requirements. The goal is to monitor the process and eliminate the factors that cause dissatisfaction in all phases of the quality cycle to ensure product quality. Whether it is a component product or a final product, their quality can be described by the quality characteristics of the size of the fluctuation around the design target value.

The smaller the fluctuation, the higher the quality level. When each quality characteristic value reaches the design target value, that is, the fluctuation is zero, then the product quality reaches the highest level. But that's never going to happen. Therefore, we must carry out quality control in the production process to minimize fluctuations. Most of the successful enterprises in the world are inseparable from the strict production process quality control. The d1-9000 quality documents of Boeing company and the SPC control chart technology of Japan are all about the production process control technology documents.

Ford motor company in the United States has a very strict quality specification system suitable for its own practice. This quality specification system basically follows the quality operation procedures of QS 9000 (including ISO 9000). These system documents cover the full range of quality management, the whole process, covering the entire product formation process, and specific, detailed provisions for each process to complete the work, and how to record all kinds of quality data. This not only guarantees the product quality but also provides a large number of technical materials for future quality improvement.