HKC-30 type water content rapid tester

The main technical parameters:

1. Design measurement temperature: 20±5℃
2. Design maximum pressure: 4Mpa
3. The highest working pressure: 0.3MPa
4.  Airtightness test pressure: 0.4MPa

• The weight of the tested material: 30g
• Measuring range of water content: 0-30%
• Measuring range of proportional method: 0-85%

Purpose:

The HKC-30 type water content rapid tester is mainly used in roads, construction, and other timber construction projects. The water content of various soils (including sand), lime, fly ash, and other uniform materials with a particle size of ≤5mm are measured. The HKC-200 rapid water content tester is mainly used for the determination of the water content of coarse-grained soil materials in roads, buildings, and other construction projects. It can also be used for the determination of the water content of agricultural soil and foundry sand.

Technical performance specifications

1. Instrument performance:
2. The accuracy of measuring water content by the instrument complies with JT051-81 “Highway Geotechnical Test Regulations” and “Pavement Material Tester and Its Test Method”

Index  Model project	HKC一200	HKC- 30
Measured material weight (g)	200	30
Measuring water content range	0~12%	0~30%
The proportion method can measure the range	0~27.3%	0~85%
Design measurement temperature	20士5C	20士5C
Design maximum pressure	4Mpa	4Mpa
Maximum working pressure	0.3Mpa	0.3Mpa
Airtightness test pressure	0.4Mpa	0.4Mpa

 

structure principle

The structure of the instrument is mainly composed of the main tank, the main tank cover, the bow-shaped fastening device, the filter, the crushing ball, and the sealing

It is composed of the mat, moisture content meter, etc.

The working principle of the instrument is based on:

1. CaC+2H2O-CH2+Ca (OH) 2
2. PV-nRT

After mixing the measured wet material with moisture and the special reagent to fully carry out the chemical reaction, gas is generated. These reaction processes are carried out in a closed pressure vessel. Since the volume of the pressure vessel is constant, the more gas, the greater the pressure, The amount of gas produced is directly proportional to the amount of water in the measured material. The pressure of the gas is indicated by the water content meter on the instrument. The dial scale of the water content meter is engraved according to the percentage of water content. The percentage of water content can be read directly from the dial for the operator.

the characteristics of the instrument

1. The characteristics of this instrument: it is the measurement result of the chemical reaction between the official special reagent and the water in the tested material during the measurement process of the instrument, and the result of the formal chemical reaction. This is not only simpler than conventional measurement methods and not limited by standard samples, but also not limited by the working place and working environment. It can be measured at any time and the results can be obtained at any time.
2. Because this instrument uses the first-level special reagents specified in the national standard, the chemical reaction is thorough during the measurement process, and the time is short (generally about 1-3 minutes to get the result) and the cost is low, so use this instrument Used to measure water content saves time and money.
3. In terms of design considerations, the instrument is calculated according to the explosive pressure intensity of the gas, so it is safe and reliable in use.
4. Using this instrument to measure the water content is more accurate than using the standard oven method when weighing errors occur. For example: using the oven method to test 200g of material, the weight is reduced by 2%. This shortage is considerably less than the water content of 2%, but when tested with this instrument, if the 2% weight is short due to careless weighing If the tested material has a moisture content of 10%, then the 2% weight shortage is actually 2% of the moisture content, that is, 10% X 2%=0.002, which is equivalent to 0.2%, which is ten percent of the error in the oven method test. One part.

operation method

1. Preparation of materials:

When sampling soil with large particles, please grind it with a tool first, and smash the large particles. If you are worried that this will lose water content during the grinding process, please make a little moisture point on the tool you use.

Place the tested material on the balance and weigh it accurately, (HKC-200 type sample weighs 200 grams, HKC-30 type sample weighs 30 grams) (note that the material should be representative and take HKC-200 type test sample More gravel and less soil, or more soil and less gravel, although the water content of samples at the same location varies greatly.

2. Operation steps:

a.Use a scoop to measure the special reagent and put it into the lid of the instrument. HKC-200 type 2 flat scoops (about 50g), HKC -30 type 1 flat scoop (about 20g), immediately cover the special reagent box tightly and do not expose it In the air, so as to avoid the failure of special reagents.

b.Put two crushed balls into the main tank of the instrument.

c.Prepare the accurately weighed material and put it into the main tank. (In order to prevent the sample from blocking the small hole at the bottom of the sample, the instrument should be tilted).

d.Place the main tank of the instrument horizontally, and immediately close the tank cover horizontally and press the tank cover tightly.

e.Hold the instrument slightly horizontal with both hands, tilt the lid of the main body up to 45°, shake the instrument vigorously, (or place the instrument on a hand-cranked vibrating stand) continuously hit the measured material in the instrument with a crushing ball And roll along the track around the inner wall of the instrument, shake it for 10 seconds, and stand still for 20 seconds, and then start the aforementioned method to shake one by one to stand still until the pointer of the instrument does not move. (Sandy soil or gravel sticky material is generally about 2 minutes, viscous Tuyi-usually takes 3-5 minutes).

f.When reading, the hands of the watch must be stable, and the dial should be at eye level with the pointer upward.

g.After the test, open the lid of the main tank slowly, deflate slowly, then pour out the contents of the tank, and clean the inner cavity of the main tank with a bottle brush. If there are residues, use a bottle brush to clean the weighing pan and paint with a damp cloth. Clean up the residue on the surface of the two crushed balls.

3.To measure the operation ratio method of high water content:

a.When weighing the material to be tested with a balance, use the HKC-200 model to weigh 100g of material. When weighing the material to be tested with a balance, the HKC-30 model should weigh 15g of material.

b.The rest of the operation steps are the same:

c.When reading the test results, please refer to Table 2. For example, the displayed value is 12% water content, and the actual water content is 27.3%.

d.This method should be used in the initial test only when the water content of the material is very high or the water content of the tested material is not determined to be beyond the test range of the instrument.

4.Those factors affect the accuracy of the displayed value and the processing methods:

a.Temperature: If the displayed value is high or low during the test, the temperature effect should be considered. If the temperature is low, the results of the first and second measurements can be omitted. After the test temperature of the instrument increases, then write down the measurement. As a result, if the temperature of the instrument is high, this is often caused by repeated application of the instrument and frequent tests. At this time, the test should be stopped and the test will be performed for a little while.

b.The internal standard residues of the instrument are not cleaned up by the test materials or special reagents, and these residues are brought into the next test process. After each measurement, they must be cleaned up.

c.The tested material and the special reagent come into contact prematurely, and the chemical reaction occurs before the main tank cover is pressed tightly, so that part of the gas escapes. Therefore, when operating, pay attention to placing the instrument horizontally and putting it on the cover. After measuring the material, press the main tank cover tightly.

d.The tested materials and the special reagents do not fully react completely. You only need to pour the contents of the main tank on paper and check it. If this is the case, you should extend the time and pay attention to the swing when repeating the test. Or grind or crush the tested material before the sample is tested.

e.The high value may be due to the fact that the pointer of the dedicated meter did not return to zero after the previous test and should be overhauled.

f.The hand of the special watch does not move. Although it is repeatedly shaken, the pointer still does not move. You can check whether you forget to put in the special reagent or the special watch is out of order. When the ratio method is used for the measurement, the test result is obtained by forgetting to refer to Table 2.

g.If the pointer of the meter moves very slowly, it should be fully ground or crushed when testing the same material next time.

h.The indication error is large, and it should be considered whether the measured material is representative or whether the weighing is accurate.

i.The indication error is large. Check whether the special reagent is effective. The special reagent is stored for an extended period of time or the special reagent is not closed in time after each use so that the special test manganese reacts with the moisture in the air and becomes invalid.

j.Man-made reading errors, such as reading the result without stopping, or when reading the indicated value, instead of reading the test result in the horizontal direction of the instrument, both eyes should face the dial of the dial. Do not read the scale indication when it deviates and tilts.

k.Special circumstances: When the oven is tested, some materials contain volatile substances. According to the standard oven method, this is also considered as the water content. This instrument can only react to the water with the special reagent. If it is tested When there are volatile substances in the material, the reading is low compared with the oven method. If the user needs to pass multiple tests and make records, a correction factor will be established.

5.Safety and precautions:

a.The gas released in the instrument is flammable, so the fire source should not be approached during the use of the instrument.

b.When the instrument is shaking, the mouth of the tank should not face people. When deflating, it should be slow and don’t rush to people’s faces.

c.The exterior of the instrument should be inspected before and after use. When any defects such as cracks, bulges, leaks, etc. are found in the instrument, they should be stopped and inspected and can be used after effective treatment.

d.During use, if the pressure gauge needle falls, the scale is not clear, the dial glass is broken, the pointer does not return to zero after deflation, or the lead seal is damaged, the special gauge should be replaced.

e.The instrument must not collide with sharp or angular objects to prevent the instrument from being damaged by stress concentration and affecting the service life and strength of the instrument.

f.The residue after the test should not be dumped randomly, especially in an unventilated room. It should be placed in a designated place or closed container in the room and buried in the soil regularly.

g.Special reagents contain calcium carbide components and are delivered to users as “dangerous goods” during transportation. Therefore, users should order in advance. Users can stock a certain amount of special reagents according to their respective usage conditions. They should be kept away from moisture and fire. source. Open flames are forbidden, and carbon dioxide fire extinguishers and dry sand should be provided if the storage capacity is large.

h.Crushing balls cannot be replaced by ordinary balls.

6.The complete set of the instrument and the contents of the factory documents:

1. 1  quick water content measuring instrument
2. 1  electronic meter
3. 1  Weighing brush
4. 1  bottle brush
5. 2  smash balls
6. 1  special reagent material spoon
7. 1  piece of cleaning cloth
8. 1 Instrument instruction manual
9. Dimensions (mm) Weight (kg)  510*180*380   9kg