Grade 9 Titanium pipes are prone to crevice corrosion in use, how to prevent it?

Titanium equipment and titanium tubes are prone to crevice corrosion in use, especially the width of the gap in about 0.5mm is prone to corrosion. Heat exchanger tube and titanium tube plate often occurs between the slot corrosion, titanium and non-metallic gasket contact, in addition, slot corrosion in the temperature of 120 ℃ above the saturated brine is prone to occur. Measures to prevent crack corrosion are: (1) avoid cracks and stagnation zones on equipment and pipelines; use titanium-palladium alloy flange welding rings or titanium gaskets and titanium composite gaskets; titanium tubes for heat exchangers and titanium tube sheets are connected by strength expansion and sealing welds; and the temperature of saturated saline solution is controlled between 70-85℃.

Titanium rods and titanium alloys can not be used in dry chlorine gas, even if the temperature is below 0 ℃, a violent chemical reaction will occur, generating titanium tetrachloride, and then decomposed into titanium dichloride, and even burning. Titanium can maintain reliable stability when the water content in chlorine is above 0.5%. The production produces a large amount of high temperature wet chlorine at 75~90℃, which needs to be cooled and dried. The main applications of titanium in ionic membrane caustic soda production equipment are: anode tank of anode system, heater of concentrated salt system, concentrated salt water pump, dilute salt water pump, dechlorination tower, dilute brine system distributor, instrument and cooler; cooler, absorption tower and separator of sodium hypochlorite system; wet chlorine cooler of chlorine treatment system; level gauge of brine system; heat exchanger of destructive system; circulating pump of alkali, alkali system lye coolers and piping for the above systems.

Titanium equipment contaminated by iron will reduce its corrosion resistance, so that titanium is easy to absorb hydrogen and cause brittle changes through hydrogen hydrogenation, the more seriously contaminated by iron, the more serious the phenomenon of titanium hydrogen absorption. Therefore, in the titanium equipment processing, transportation, installation, overhaul and maintenance, should not be as much as possible to use steel tools.

Due to the excellent corrosion resistance of titanium, the application of titanium equipment in the ionic membrane caustic soda industry has obvious advantages:Firstly, it prolongs the service life of the equipment, reduces the number of times of maintenance of the equipment and pipelines, and fundamentally solves the problem of running, bubbling, dripping and leaking, saves energy and increases the effective production time. Secondly, the use of titanium equipment and titanium pipes can reduce the cost of equipment and piping materials and lower production costs. The use of titanium materials, although the one-time investment is large, but from a comprehensive point of view, it is economical in the long run. The actual investment of titanium material is about 2 times of stainless steel, the life of titanium products is long, the cost of updating equipment and piping and frequent repairs are reduced, which actually saves money and reduces the cost.