Imported bearings have corrosion, which not only affects the accuracy and surface roughness, but also reduces the service life, and even scrapped and cannot be used. Imported bearing rust prevention is an important work, especially the rust prevention between processes, like bearings in the heat treatment workshop after pickling, cleaning, grinding processing, there are many processes. When the product is not produced by running water, it is stored in the middle warehouse after processing in a sequence, so the bearing rings stored between processes must be rust-proof. The traditional anti-rust oil anti-rust method as anti-rust paint and the anti-rust methods generally used between bearing processes are as follows:

1. Soak in anti-rust tank

The bearing trap is immersed in 5% sodium nitrite and 0.6% sodium carbonate aqueous solution, the anti-rust effect is good, but many anti-rust tanks and other equipment occupy a lot of space, and the management is not convenient.

2. Dip in concentrated sodium nitrite solution

After cleaning the product, immerse it in a solution containing 15%-20% sodium nitrite and 0.6% sodium carbonate, and then stack it up. Using this method, its rust prevention period is short, generally only 7-14 days, and in the rainy season, due to the wet weather, it can only be maintained for 2-3 days and must be re-processed, which requires labor and money.

3. Apply oil

Apply anti-rust oil similar to anti-rust paint as the finished product. This method must be cleaned before the next process, which is more troublesome.

New anti-rust technology is introduced

After joint research with related manufacturers, many years of production practice shows that the rust prevention between processes has been improved many times to use the spray type of rust prevention effect is better. At first, the roller rust prevention was tested, the semi-finished products and finished products were washed once a day with sodium nitrite solution, and the test results after 3 months did not find rust, and now the semi-finished bearing snare is sprayed with rust prevention, the effect is the same. Spray type rust prevention process is relatively simple, the method is as follows:

1. Purchase and construction of equipment

According to the storage of semi-finished products, establish an intermediate warehouse, the ground with cement floor, the middle can be set up a walkway, about 1.5m, used to pass the bearing ring car. At the end of the channel, put a storage of sodium nitrite aqueous solution pool, the solution formula is 5%-10% sodium nitrite plus 0.6% sodium carbonate, and do a return ditch on the ground, and then pile the bearing rings on the floor on both sides, keeping 0.6m corridor between each pile of bearing rings. The design of the intermediate reservoir is about 64m2, and the sodium nitrite aqueous solution pool is 1m3.

2. Process method

Every morning, the sodium nitrite solution is washed once, the aqueous solution is sucked out from the pool by the pump, and the rubber pipe is passed to the shower head, and the bearing ring is washed like a spray. The rinsed aqueous solution flows back to the pool through the return ditch. On the upper part of the pool at the end of the return ditch, a filter is made with fine wire mesh and gauze to make the textile dust and dirt flow into the pool. The intermediate storage shall be kept clean. The solution in the pool is tested every 2 days and supplemented according to the test results. The replacement period of the solution in the pool is carried out in different months, from April to September, every 2 weeks, and from October to March of the following year, every month.

Conclusion Spray type rust prevention, management is more convenient, but also save labor, in the past, the middle warehouse with 2 people can not complete the rust prevention, now with one person can also do other work, from the rust prevention effect is also very significant. In March 2003, more than 4,000 grains of 7002136 and 3620 rollers were used for spray rust prevention, which remained very bright and without rust for more than a year. In addition, the consumption of chemicals also has great savings, in the past, the roller workshop needs to consume more than 4,000 kilograms of sodium nitrite per month, and now only 200 kilograms, saving nearly half. The spray type rust prevention method has been tested and used by relevant manufacturers in recent years, and it has been proved that it is very suitable for medium and large scale bearing semi-finished products with many batches and long cycle.