Life everywhere need fasteners, now so important, in the fasteners for cleaning the experience of the titanium alloy screws to talk a summarized below: not good cleaning method, mainly for cold heading adhered on the surface of the processing or machining titanium alloy screws of cooling oil residual oil, oil heat treatment quenching fastener surface residual oil after cleaning.
Titanium alloy screw first method alkaline water cleaning method: the simplest alkaline water cleaning is direct heating or indirect heating cleaning tank, cleaning solution is 3% ~ 10% N2CO3 or NaOH aqueous solution. For carburizing and carbonitriding self-drilling titanium alloy screws, tempering before the middle of the multi-purpose cleaning heating to 50 ~ 70 ℃ 5% ~ 10% sodium carbonate solution. Connected mesh belt furnace belongs to this class. Titanium alloy screw cleaning titanium alloy screw is usually sprayed and immersed in dual mode. If hot water is used for washing, it is better to wash with hot water. Finally, the high-pressure air is used for drying. The main drawback of alkaline water cleaning method is that the cleaning effect is not very good, especially the blind hole of the fastener and the spot and residue of the groove. The waste water produced by alkaline water cleaning must be neutralized, and waste oil can be recovered to meet the environmental requirements.
Titanium alloy screws second method metal cleaning agent cleaning method is: get rid of disadvantages of alkaline cleaning method, improve the cleaning effect, special metal cleaning agent can be used at present, the cleaning agent in 40 ~ 70 ℃ water diluted to 1% ~ 3% solution, the fasteners in solution immerse 15 ~ 20 min, and then rinse with hot water, the last use dryer dehydration processing. Can be used in cleaning machine. Metal cleaning agent cleaning method of defect is expensive, and has a bad smell, has certain corrosion effect to titanium alloy screws, wastewater pollution of the environment, therefore, must to deal with waste water, and recycling waste oil.
The third method of titanium alloy screw cleaning is organic solvent cleaning method: it is cleaned by organic solvent such as trichloroethane and trichloroethylene, and the cleaning effect is good. When the quenching fastener is cleaned by soaking or spraying under normal pressure, the volatile and splash pollution environment of organic solvents. For this purpose, the application of vacuum sealed decompression solvent cleaning method of whole set, using vacuum pump to discharge air, titanium alloy screws in the absence of air and high density of the vapor contact, further improve the cleaning effect, and by vacuum distilling recycling solvent and oil. The solvent content in the recovered oil was reduced from 20% to less than 4%, less than 50ppm in the environmental hygiene regulation of trichloroethylene.
The fourth method of the titanium alloy screw burning degreasing method: cold heading or machined titanium alloy screws need to be cleaned off the surface oil before entering the heat treatment process. To this end, can match the fasteners in degreasing furnace heating to 350 ~ 400 ℃ oil vaporization or burning, in order to achieve the purpose of the titanium alloy screws to oil or surface phosphorus removal effect. The burning degreasing method is only suitable for cleaning before heat treatment, and can also clean the light, low viscosity and low boiling oil of cooling oil and anti-rust liquid. High viscosity, high boiling point heavy quenching oil will have a large amount of residue and carbon black attached to the fastener surface, which will not achieve the cleaning purpose.
For high cleaning the surface of the fasteners, such as aviation, automobile engine connecting rod bolt, at present, using advanced cleaning technology of vacuum or ultrasound to replace the commonly used on the atmospheric ozone layer has the damaging effects of chlorinated hydrocarbons as solvent cleaning method, can realize efficient environmental protection cleaning.
