JPS61259154A - Method for measuring salinity - Google Patents

Abstract

PURPOSE:To shorten a required measuring time and to make it possible to accurately measure salinity, by adhereing the salt adhered to the definite area of a surface to be measured to the surface of a pressure-sensitive material and introducing said pressure-sensitive material in a definite amount of water to elute the salt to measure the conductivity of the formed salt solution. CONSTITUTION:An adhesive tape is adhered to a measuring area dried after washing and the salt on the surface of a film is adhered to the adhesive tape and, thereafter, the adhesive tape is peeled off to collect the salt adhered to the surface of the film. Next, the adhesive tape having collected the salt is introduced in a beaker in which about 200ml of distilled water was received to dissolve the salt. The electric conductivity of the solution in the beaker is measured by using an electric conductivity meter to calculate the salinity of the solution in the beaker from a preliminarily formed calibration curve and the salt adhesion amount per unit area on the surface of the film is calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for measuring the concentration of salt adhering to the surface of ships, marine structures, bridges, and other objects.

[Technical background]

Knowing the concentration of salt adhering to the surface of ships, offshore structures, bridges, and other objects is important for subsequent processes, such as determining whether painting is possible or estimating the progress of corrosion. It is also necessary from the viewpoint of product quality control.

For example, when painting a ship's exterior, it is usually applied 3 to 5 times, but since the amount of salt adhering to the coated surface (base coat surface) greatly affects the lifespan of the paint film, it is recommended to wash it with water before applying multiple coats. It is necessary to remove salt with water and check the effectiveness of washing with water.

[Conventional technology]

The measurement procedure of the conventional salt concentration measurement method for the surface of an object, for example, the surface of an undercoat coating on a ship's outer panel, is as follows.

1) Decide on the measurement points (approximately 10 points per boat) and divide them with masking tape so that the sampling area of each measurement point is constant.

2) Add 40-40ml of distilled water to 11 Bee Power (4).

3) Thoroughly moisten gauze (3oox3oom) with distilled water (4).

4) Apply damp gauze to the measurement area and wipe off the salt on the surface of the coating film.

5) Rinse the wiped gauze with distilled water from Bee Power (4) and squeeze it gently.

6) The remaining liquid from Bee Force (4) is stored in another Bee Force 03).

7) Repeat operations 1) to 6) three times.

8) Wash the inside of the carton (4) using 80 tlt of distilled water, and transfer the gauze and washing liquid to a beaker (4).

9) Measure the electrical conductivity of the Bee Force (B) internal solution using an electrical conductivity meter.

10) Calculate the salt concentration in (6) from a previously prepared calibration curve (relationship between electrical conductivity and salt concentration) and determine the amount of salt deposited per unit area of the coating surface.

[Problem that the invention seeks to solve]

However, the conventional salt concentration measurement method described above has the following drawbacks.

1) - Measurements are taken at approximately 10 locations per boat, but sampling takes time, so the measurement time per boat is 2.
It takes ~3 hours.

Please note that other work will stop during this time (during measurement), so
Considering the waiting time of workers engaged in other work, this can be said to be a considerable loss time in the process.

2) Since there are many instruments used for sampling (bee force, graduated cylinder, etc.), it is dangerous to perform measurements at high places.

[Object of the present invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a salt concentration measurement method that eliminates the above-mentioned drawbacks of conventional salt concentration measurement methods.

[Configuration of the present invention]

And, as a means for achieving the above object, the present invention uses an adhesive material in place of the gauze in the conventional technique. That is, in the present invention, after the salt adhering within a certain area of the surface to be measured is made to adhere to the surface of the adhesive material, the salt-adhesive adhesive material is placed in quantitative replenishment water to elute the salt, and then the salt eluate is This is a salinity concentration measurement method characterized by measuring electrical conductivity and determining the salinity concentration of the surface to be measured from the relationship between the gauging conductivity and the salinity concentration, which are determined in advance. .

As the adhesive material used in the present invention, adhesive tapes, adhesive sheets, adhesive tapes, adhesive sheets, etc. can be used.

〔Example〕

Hereinafter, a case where an adhesive tape is used as an example of the present invention will be described. The measurement procedure in this case is as follows.

1) Attach an adhesive tape to the measurement area that has been washed and dried, and allow the salt on the surface of the coating to adhere to the adhesive tape.

2) Peel off the adhesive tape) and collect the salt adhering to the surface of the paint film.

3) Place the adhesive tape containing the salt sample into a beaker containing 200ml of distilled water to dissolve the salt.

4) Measure the electrical conductivity of the liquid inside the beaker using an electrical conductivity meter.

5) Calculate the salt concentration of the liquid inside the beaker from the calibration curve prepared in advance, and determine the amount of salt deposited per unit area of the coating surface.

[Experiment example]

A test piece coated with epoxy resin was immersed in seawater for about an hour and then dried at room temperature.
The amount of salt deposited on the surface of the coating film was measured using the conventional method and the present invention.

The results are shown in Table 1. As is clear from Table 1, compared to the conventional method, the present invention had less variation in data and was able to perform measurements in a shorter time.

Table 1 [Effects of the present invention] The present invention has the following effects.

1) With the present invention, in order to sample the salt content on the surface of an object, it is only necessary to attach a tape or sheet-like adhesive material to the surface of the object and then peel it off, so the sampling operation is very simple and the time required for measurement is short. - has the advantage of being shorter. Further, in the present invention, if the tape or sheet-like adhesive material is divided in advance to have a constant area, there is an advantage that the step of dividing the object surface into a constant area using masking tape can be omitted.

2) In the present invention, since there are few instruments used for sampling, it is easy to perform measurements in high places or in narrow spaces, and it is also advantageous in that it is safe.

3) In the conventional technology, the sampled liquid may drip from the case etc., which may lead to inaccurate measurement results, but the present invention does not have this drawback, and the bottom surface of the object, e.g. This method also has the advantage of being able to more accurately collect salt from the bottom surface of a ship than conventional methods, and as a result, determining whether or not it can be painted can be done more accurately.

Claims (1)

[Claims] After attaching the salt adhered within a certain area of the surface to be measured to the surface of the adhesive material, the salt-adhering adhesive material is placed in quantitatively purified water to elute the salt, and then the conductivity of the salt eluate is measured. A salinity concentration measuring method characterized in that the salinity concentration of the surface to be measured is determined from the relationship between the electrical conductivity and the salinity concentration that has been determined in advance.