NJAL-H type rapid alkali content tester for concrete

NJAL-H Type Concrete Alkali Content Rapid Tester, Handheld Alkali Content Rapid Tester Product Usage

Concrete raw materials contain alkali (potassium, sodium ions). After the concrete is exposed to sufficient humidity for a period of time, the alkali (potassium, sodium ions) in the concrete will react with the active silicon in the coarse and fine aggregates, causing structural expansion and cracking, known as alkali aggregate reaction. Due to the harmful effects of alkali aggregate reaction on concrete structures, the limit of alkali content in concrete is highly valued both domestically and internationally.

According to relevant standards such as the "Limit Values for Alkali Content in Concrete" CECS 53:93 and the "Durability Evaluation Standards for Concrete Structures" CECS 220:2007, the alkali content of concrete refers to the content of equivalent sodium oxide in concrete, measured in kg/m3. The alkali content of concrete raw materials refers to the content of equivalent sodium oxide in raw materials, measured in weight percentage (%). The equivalent sodium oxide content refers to the sum of sodium oxide and 0.658 times the amount of potassium oxide, that is, "equivalent sodium oxide content=Na2O+0.658 × K2O".

This instrument adopts the Ion Selective Electrode (ISE) method, which uses imported composite potassium ion electrodes and composite sodium ion electrodes from the United States to quickly determine the alkali content (%) in concrete (including fresh concrete, wet concrete, hard concrete powder samples, etc.) and concrete raw materials (including cement, chemical additives, admixtures, etc.) at room temperature.

NJAL-H type concrete alkali content rapid tester, handheld alkali content rapid tester detection method: ISE method

Test indicator: Alkali content of concrete and raw materials, i.e. equivalent sodium oxide content Na2O (%)

Handheld alkali content rapid analyzer execution standard

1. Standard for Alkali Content Limits of Concrete CECS 53:93

2. "Durability Evaluation Standards for Concrete Structures" CECS 220:2007

Product Features of Handheld Alkali Content Rapid Tester

1. Color screen LCD, calibration curve display, quick measurement of concrete alkali content

2. Unique anti ion interference agent, enhancing ion concentration while removing the interference of various metals

3. High precision potassium and sodium ion composite electrode with stable performance

4. Color screen LCD direct display, instant printing with handheld printer, and reasonable use and operation

5. Unique self diagnostic function, * upper computer analysis software

6. Large capacity data storage, capable of storing 100 sets of test data

7. Continuous data recording, safe and reliable

Test objects: fresh concrete, wet concrete, and concrete raw materials.

Detection principle of handheld alkali content rapid analyzer

NJAL-H handheld alkali content rapid analyzer uses ion selective electrode (ISE) method to quickly determine the alkali content of water-soluble substances such as concrete, sand and gravel, and additives.

Pre treat concrete or other samples during use. Immerse two pre activated and calibrated electrodes into a mixed solution as instructed, with one measuring sodium ion content and the other measuring potassium ion content. The instrument can convert the measured voltage data (mv) into Na2O and K2O content (%) using calibration curves, and automatically obtain the concrete alkali percentage Na2O (%) by inputting the results into the calculation formula in the host computer. After electrode activation, each experimental process only takes 10 minutes.

The correlation coefficient between NJAL-H and flame spectroscopy test results is 0.97%, and the test deviation is within 5%.

Technical parameters of handheld alkali content rapid analyzer

Power supply voltage: AC 220V

Working voltage: DC 3.6V

Measurement accuracy: ≤ 10%

Printer operating voltage: DC 5V

Data storage capacity: 100 sets

PC communication parameters: baud rate 2400

Collection time: ≤ 3 minutes

Standby time:>24 hours

Whole machine weight: 240 g

LCD size: 128 * 128

Test steps for handheld alkali content rapid analyzer

1. Activate the electrode

2. Weigh the sample and perform pre-treatment according to the instructions

3. Calibrate the electrode and measure the sample solution to be tested

4. Display measurement data

Test results of handheld alkali content rapid analyzer

1. Percentage of alkali content in concrete (%)

2. Percentage of Sodium Oxide in Concrete (%)

3. Percentage of potassium oxide in concrete (%)

Measurement range: 0.001% to 30.000%

Measurement accuracy: ± 10%

Operating temperature: 0 ℃~45 ℃.

Resolution: 0.001

Instrument specifications

Host size: 180 * 70 * 30 (mm)

Host weight: 0.4 kg

Host dimensions: 390 * 310 * 150 (mm)

Total weight: 4.5 kg

System Configuration

1. NJAL-H handheld concrete alkali content rapid tester

2. Imported composite sodium ion selective electrode

3. Imported composite potassium ion selective electrode

4. Calibration solution, ion strength regulator

5. Charger

6. Handheld micro printer

7. Upper computer analysis software