Cleaning alkaline

Alkaline clean by immersing parts in alkaline cleaner (nonsilicated), 5—10% by volume, for 5 min at 66 °C. For suitable formulations, contact ChemetaU Oakite Products (Berkeley Heights, NJ, www.chemetallamericas.com) 

Modified HF Acid-Nitric Acid Pickle Immerse for 2 min at room temperature in the following solution (Table 6.24) 

Wrap the parts in clean craft paper until ready to bond 

This method yields excellent durability for both 6,4 titanium and chemically pure (CP) titanium. The former, however, exhibits a loss of lap-shear strength after 5 years outdoor weathering. The CP titanium does not show this effect. 

---

The transducers are typically mounted on an outside wall of the cleaning tank, but may also be mounted on the inside of the tank below the solution level in a sealed container. Alkaline cleaning solutions are typically at the same concentration and temperature as for a normal immersion cleaner, but the time required to clean may be less because of the ultrasonic effect. Like electrocleaning, ultrasonic cleaning produces an extremely clean surface. The main drawback is the relatively high cost. 

Fig. 36. Pari of a Morphology Catalog illustrating the unacceptable morphologies resulting from incorrect surface treatment (a) Turco alkaline clean with no FPL etch, and (b) Amchem deoxidizer with no FPL etch [169. ...

Resin-based TSK-GEL PW columns are durable to alkaline conditions, which cannot be used with silica-based columns. Such durability facilitates separations with basic eluents and allows the use of alkaline cleaning reagents. 

No dimensional change Proprietary brands of alkaline cleaners may be used provided these do not attack metal Soda ash with washing soda and soap are suitable for preparing alkaline cleaning baths No dimensional change unless much impurity is present For small delicate parts 0 1-0-5% silver chromate may be added to reduce attack caused by impurities such as chloride in corrosion product... 

Removal of general organic fouling is best achieved by alkaline cleaning based on caustic, EDTA, and a surfactant such as sodium dodecyl sulfate or sodium lauryl sulfate. 

Under alkaline cleaning conditions, sodium gluconate can be used to similar effect because the gluconate-ferric ion complex is particularly stable. 

Installation of an ultrafiltration system that recovers 30 kg/d (65 lb/d) of waste oil and purifies 1135 kg/d (2500 lb/d) of alkaline cleaning solution for reuse, which resulted in a reduction of 5-day biochemical oxygen demand (BOD5) loadings to the treatment system of 200 kg/ month (370 lb/month). This avoided the need for installation of additional treatment. 

In-tank filtration. Steel finishing electroplating and alkaline cleaning operations use in-tank filters to extend process bath life by removing contaminants in the form of suspended solids. Solids are usually disposed of offsite. Devices such as granular activated carbon filters remove dissolved contaminants, such as organic constituents. 

The no-rinse conversion coating and the Zincrometal processes require a coil that is clean, warm, and dry. For these processes a squeegee roll and forced air drying are used to assure a clean, dry coil following alkaline cleaning and rinsing. 

Several processes are used when enameling on steel. The parts to be coated are first alkaline cleaned and rinsed to remove soils. An acid treatment step and rinse follow in that sulfuric acid,... 

As it is essential to remove all the oil and grease on the copper before coating, the part is first alkaline cleaned, degreased, or annealed. After cleaning, the part is then typically pickled for oxide removal. 

Water rinses are used in surface preparation operations such as acid pickling, alkaline cleaning, and nickel deposition to remove any process solution film left from the previous bath. A water rinse may also follow the neutralization step. Another common water use is in the ball milling process, which uses water as the vehicle for the enamel ingredients, as a cooling medium, and for cleaning the equipment. Coating application processes normally use wet spray booths to capture oversprayed enamel particles. Water wash spray booths use a water curtain into which the enamel particles are blown and captured. 

---