A general method of determining corrosion rates is by using Crystal Industrial’s corrosion coupons from India, which are uniform in size, pre-measured pieces of metal. Corrosion coupons, demonstrative of system metals, are implanted into a coupon rack placed on the system to be observed. Regularly, system water is allowed to pass over the corrosion coupons for around 30 – 90 days. The coupons are then retrieved and returned to a laboratory where they are cleaned and re-weighed. From this decrease in weight and the estimations of the coupon, a corrosion rate in mils/year (mpy) is obtained. 1.0 mil/year changes over into 1/1,000th of an inch of metal loss per year.

The below mentioned describes different kinds of attack that can be perceived on coupons:

Generalized Attack – Even corrosion on entire surface of the coupon. Not generally a concern unless the mpy is raised.

Corrosive Attack – An ordinary term given to any cut on the metal surface caused by corrosion. Pits can vary substantially in size, depth and thickness. Under 10 pits for every side is at times named isolated corrosion.

Accurate monitoring of corrosion rates in any type of atmosphere is crucial when seen with regard to maintenance and repair costs associated with corrosion and material lapse. Crystal Industrial’s Test coupons from India give an affordable technique for on-line monitoring that will allow you to sufficiently measure the corrosion in your system. By assessing the mils-per-year corrosion rate of an exposed coupon, valuable information can be provided regarding the material’s life expectancy.

Crystal Industrial from India can make coupons in any size, frame, or material you need. Crystal Industrial’s corrosion coupons from India can be stenciled with metal blend and arrangement of numbers for proper recognition. Process test reports, recognizing component blends of materials used, are provided on all demands.

While asking for test coupons, please be prepared to provide the businessperson with information as to the type of material you are monitoring, the style and size of the coupons you require, surface finish required, and if possible, mounting gap size and region.

Corrosion rates can vary among welded and non-welded metals, therefore it is recommended to monitor the behaviour of both circumstances. Studies incorporate investigation of the parent material, the heat-affected zone and the weld metal. The surface effects created by welding, development of heat-tint or oxidation, fluxing action of slag, and the deliquescence of slag can be important parameters in the corrosion reaction of metals.

Ideally, the coupon used should be a similar thickness and welded with an identical welding process from the material used in the production instrument. Usually this is not sensible hence a representative specimen must be analyzed.

Specimen are fragmentized smooth after welding, unless usually showed, to give a uniform surface for microscopical scrutiny.

Finishes

Crystal Industrial’s Coupons from India can be supplied with a variety of finishes as per your particular application. Some of the general finishes available are characterized underneath:

Mill – finish as produced from mill

Fine texture and typically used in corrosion monitoring for instance, pitting reviews, where uniform surface finish is needed.

Twofold Disk Ground – super fine finish using an unsmooth plate that leaves nominal deposit. Extremely good for investigations where surface finish is critical.