1. Technological process:
Online pre-cleaning - pre-degreasing - degreasing - water washing 1- water washing 2- table adjustment - phosphating - water washing 3- cycle pure water washing - pure water washing 1- electrophoresis - tank ultrafiltration water washing -UF1 water washing 2- off lines-degreasing - drying
2. Main Design basis:
The maximum length of the workpiece is 3.7 meters, the tank size is 6.5×3.5×2.7, the step-type (intermittent type), the annual working day is 320 days, the full work day is 20 hours, the normal production beat is 6 minutes, the annual designed production capacity is 38400. Due to the use of step-type production, considering the current auxiliary materials, the production tempo can only be adjusted to 5 minutes at most. If the emphasis is given to the possibility of production expansion, the length and height of tank can be appropriately relaxed, so as to increase the number of electrophoretic pendant per unit and increase the productivity by multiples.
The prices in the table below are all made of ordinary hot rolled steel plate or pipe, and the filter is made of stainless steel. The price of 10mm plate is 4500 YUAN/ton. If the use of stainless steel, the market price of 316 stainless steel plate 29.5 yuan/kg, 125 pipe material 39 yuan, the cost is expected to increase at least 3 times.
3. Main Precautions for equipment installation:
1) Channel: 6-10mm ordinary carbon steel plate is lined with epoxy FRP 4-6mm, external I-steel or channel steel frame, joints are fully welded, internal corners are curved. Base 150-200mm I-steel. Each tank shall be lined with fiberglass. The electrophoresis tank shall be resistant to dry pressure of 2W.
2) Pumps: Double-mechanical sealed stainless steel pumps are used for electrophoresis and UF1 washing, with a speed of 1450 and a flow rate of 120m /H. Main spare parts are available. Other tank pump, can be used ordinary acid and alkali pump, flow of 100T, inlet with filter screen, pipe filter.
3) Filter: Electrophoresis tank using 6 bags filter, and circulation pump flow matching, filtration accuracy of 50 m.
4) Rectifier system: voltage fluctuation rate is lower than 5%, adjustable from 0 to 350V, the rated current shall be determined according to the maximum size of electrophoresis workpiece, generally 1200A can meet the requirements.
5) Ultrafilter and pure water device, determine the penetration and water production amount according to the production beat and workpiece size.
6) Liquid cooling and insulation in the electrophoresis tank: start the refrigeration unit in summer. If the winter temperature is low (below 10℃), the workshop must keep warm; otherwise, the heating system must be added to the electrophoresis tank liquid.
7) The specific number of anode tubes shall be adjusted according to the actual size of the workpiece to ensure that the pole ratio is 1:4. If the product type of electrophoresis is not fixed, it is suggested that the number of electrode tubes can be adjusted.
8) Hanging tools: The specific quantity of hanging tools shall be adjusted according to actual production needs, and the hanging tools shall be treated with acid and alkali resistance in advance. It can be processed by electrophoresis in the trial production stage and dried for standby use.
9) The estimated price of the main purchased equipment at the electrophoresis station (inaccurate) : 100,000 yuan for pure water treatment equipment, 100,000 yuan for anode system, 100,000 yuan for ultrafiltration system, 100,000 yuan for refrigerating unit including cold water tank, 50,000 yuan for tank body, 50,000 yuan for support i-steel or channel steel, 50,000 yuan for valve pipe and flow meter, 50,000 yuan for rectifier cabinet and 50,000 yuan for manual welding material.
4. Special Notes:
This scheme is mainly prepared for the purpose of controlling investment. Therefore, the operation and process management in the later stage are bound to increase the corresponding cost, and some seemingly unimportant performance is also missing.
1) Material selection: ordinary carbon steel with protective coating is adopted instead of all stainless steel. Therefore, we must pay attention to the management in the future, such as the selection of coating materials (pretreatment, electrophoresis), not the selection of strong acid and alkaline products; In the process control also need to pay attention to related matters.
2) No complete closure. Generally, electrophoretic coating lines are completely sealed for several purposes. The first is to ensure that the liquid in each tank is not polluted by the outside world; the second is to prevent the acidic substances on the electrophoretic coating line from polluting the outside world; the third is to prevent the liquid splash damage equipment, etc. However, such hazards can also be minimized if environmental controls are strengthened in the construction of the workshop, management is strengthened in the production process, and attention is paid to the selection of materials. When the production is stopped, proper covering shall be carried out for each tank.
3) In the selection of equipment, it is suggested to choose the most cost-effective products and the most perfect after-sales service as far as possible. It is also suggested to do so in the future selection of materials, which is conducive to the on-site process management.
4) For the electrophoretic coating line in this scheme, as long as the management is perfect and the personnel operate normally, the normal production can be guaranteed for more than 6 years. If it can be more than 10 years, daily management is needed to cooperate.
5) As the installation of electrophoretic coating line equipment is a system project, it is recommended to make relevant plans in advance, and check and confirm the equipment step by step according to the agreement with the equipment installation company, so as to ensure the quality.