Real knowledge comes from practice, no matter how good the theory is, it needs practical support.
的 Many difficult problems encountered in the production of ceramic tiles, often can not find the "standard answer" from professional books. Obviously, we need experts with actual experience to come forward and answer practical problems such as process operation, process production, and equipment maintenance.
Qiu Huijun, Senior Engineer of Ceramic Machinery at Jingdezhen Ceramic Industry Design and Research Institute, and former Chief Engineer and Plant Manager of Changshu Pan Asia Building Ceramic Industry Co., Ltd. During his working days in the factory, he accumulated a wealth of production experience. Now, he is going to extract these experiences into real cases, and share with readers in detail the causes, processing ideas, solutions, and later effects.
原因 Cause of the incident
的 The hot blast stove used with the spray drying tower did not work, the reason was that the burner Weishaupt Burner (nozzle model: RL 11 ZMD) produced by Max Weishaupt GmbH of West Germany in 1993 had no oil output pressure. The range of the pressure gauge is 0-25kg / cm2, and the pressure reading displayed on the gauge is 0kg / cm2.
(1) Check the entire oil system (including the gear oil pump itself), no oil leakage was found;
(2) Check the oil temperature and find that the oil temperature is not too high;
(3) The filter in the oil circuit was replaced, but the pressure still couldn't go up;
(4) After disassembling the gear oil pump (model: TA4C), it is found that it is a planetary gear train structure. Traces of wear can be seen between the intermeshing gears; the pump body, between the coggings and the end cover have not completely sealed the volume, it is difficult to form an effective pressure during the oil pressure process;
(5) Go to the spare parts warehouse to find that there are no spare parts for the gear oil pump. The gear oil pump is not sold in mainland China and can only be sold through the Taiwan distributor;
(6) Check the reserves of the silo and calculate the effective time that the production can be maintained:
At the time, there were 4 silos for floor tiles and wall bricks, each with a capacity of 7.5 tons. There are 2 full warehouses and 1 half warehouses in the floor tiles, which are about 188 tons of powder. There is only one full warehouse, one and a half warehouses, and the wall tiles are about 110 tons.
Product sales were growing at that time. The orders placed are mainly 200 × 300 (mm) wall tiles and 300 × 300 (mm) floor tiles, and a small number of 250 × 250 (mm) floor tiles.
According to the data measured at the production site:
200 × 300 (mm) wall brick, the powder is 0.876kg / piece;
250 × 250 (mm) floor tiles, using powder for 0.987kg / piece;
For floor tiles of 300 × 300 (mm), the powder used is 1.476 kg / piece.
The production site has a total of 80 blank storage trucks, of which 46 are full, but not enough for two furnaces to burn in one day.
Each storage car has 50 floors. If you make a floor tile of 300 × 300 (mm), set a storage car with 4 rows on each floor, and each row has 5 pieces (that is, 20 pieces per layer), then each fully loaded storage car has 1,000 pieces.
Adjust the kiln speed of the two kiln to 5800 square meters per day. In this way, without considering factors such as the weighing error of the electronic scale and the loss of each process of the production line (including screen printing and sticking, broken corners of the brick blank, etc.), or the interruption of the blank body into the kiln, the two kiln needs about 100 tons per day Powder, using this as a starting point to balance and coordinate the production of various processes.
Considering the aging time of the powder and the factors such as line change, production change, material change, shift change, etc., it is obvious that if the new gear oil pump cannot be shipped to the factory within 48 hours, it will inevitably result in production suspension.
7 (7) Difficulties and points of handling problems
Difficult point one: Because I just started working in the company, the status and proportion of powder loss in each process are unknown.
Therefore, I may be too optimistic about the calculation that the two kilns need 100 tons of powder per day. Although the problem caused by measurement errors can be buffered by reducing the kiln speed, once the daily output drops too much, I am afraid it is difficult to make a difference with the boss.
Difficult point two: The supplier of this batch of diesel oil is the wife of the company's production plant manager.
After disassembling the gear oil pump, it can be confirmed that impurities in the inferior No. 0 diesel oil cause serious wear and tear on the gear oil pump, resulting in oil pressure not being able to rise. It is not difficult to find out the reason. The supplier of this batch of diesel oil is the wife of the company's production plant manager. One of the reasons why the producers agreed to buy the diesel was because of its low price. He didn't know that the quality would be so poor.
(1) I insist on replacing the gear oil pump and require delivery within 2 days at the latest. In any case, if the gear oil pump is not changed, the pressure of the pump oil will not go up, and finally the production will be stopped. As the chief engineer, I have to solve the problem of stopping production.
(2) On the evening of the 2nd day, the wife and children of the Taiwan boss carried gear oil pumps to Hong Kong-Shanghai-factory. At this time, the clock had passed 32 hours.
(3) With the presence of the factory manager, we installed a new gear oil pump. After starting up, the pressure gauge's reading rose to 11kg / cm2. Nothing happened that night, and the spray drying tower was in normal production.
(4) At noon the next day, the director of the raw materials workshop reported that the pressure gauge reading had returned to zero just now. It shows that in less than a day, a brand-new gear oil pump was worn out by inferior diesel.
We arrived at the scene as soon as possible. I reported to the boss in Taiwan and requested to buy another new gear oil pump, otherwise I will face production suspension.
I listed some facts: since the production, the oil tanks and oil pipelines have never been cleaned, and there are many impurities floating in the area; some filters have no effect and must be replaced; in addition, when buying diesel It undergoes acceptance.
In the process of the boss sending someone to buy a gear oil pump, the production manager and I organized a mechanic to clean the piping system and filter the diesel with a stainless steel filter. During the filtration process, the production plant director changed a local PetroChina supplier.
(5) The next night, the second new gear oil pump was sent from Taiwan to the factory. Also brought is a third new gear oil pump for backup. Of course, after the second new gear oil pump was installed, it was in normal working condition.
后 Post hoc measures
Because of the occurrence of this incident and the boss's intervention provided an opportunity for deepening management, a series of related rules and regulations were formulated, including the acceptance standards for diesel oil entering the plant; the job responsibility system for personnel in various positions.
It is gratifying that since then, although the equipment in the spray drying system still has problems, and it also jeopardizes the shutdown, the gear oil pump was worn by inferior diesel and the entire plant faced a shutdown.