JPH0711482B2 - Moisture measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is used when moisture remaining in a closed container such as a compressor or a heat exchanger is measured by a sampling inspection for quality control. The present invention relates to the structure of a moisture measuring device.

(Prior Art) As this type of moisture measuring device, there are a Karl-Fisher method and a cold trap method. For example, industrial measurement technology general system 10, humidity / moisture measurement, 1965
Published on the first edition of Nikkan Kogyo Shimbun on March 31st, it is known that the former contents are disclosed on page 25, and the latter contents are disclosed on Refrigeration and Air Conditioning Technology Volume 24 / No. 280, page 13. As shown in FIG. 7, the measuring device by the Karl Fisher method is as follows.
A Karl-Fisher reagent (a Karl-Fisher reagent which passes through the inside of the work to be inspected (W) and causes nitrogen gas containing water to bubble in a collection bottle (B) containing a solvent, and then reacts with water at a constant ratio ( KF) is titrated and the amount of water is determined from the amount.

On the other hand, as shown in FIG. 8, the measuring apparatus using the cold trap method is provided with a cold trap (T) which is connected to the gas outlet side of the workpiece (W) to be inspected and cooled to a low temperature of about −70 ° C. The actual amount of water accumulated in the trap (T) is measured or calibrated by allowing the nitrogen gas containing water passing through the work (W) to flow into the cold trap (T) to condense the water. It was done like this.

(Problems to be Solved by the Invention) Among the above two devices, the former has a nitrogen gas flow rate of 0.3 to
Work (W) because it is limited within the range of 0.5 l / min
The larger the size, the longer it takes to measure, and the more suitable it is for measurements up to a water content of about 100 mg. However, for example, in the case of a heat exchanger used for a large-sized refrigerator of 10 horsepower or more, it is difficult to measure. Further, since the Karl Fisher reagent (KF) is highly corrosive, glass is used as the main part of the device, and it is easy to break, so it is troublesome to handle it carefully.

On the other hand, the latter has the drawback that the flow rate of nitrogen gas is limited as in the Karl-Fisher method, and therefore it has the drawback that it takes a long time to measure the arrow tension.
It takes about 5 hours of measurement time and is inefficient.

Further, since this device requires a low temperature cooling device, the size of the entire device is increased and the cost is increased.

As described above, the present invention has been made in consideration of the fact that each of the conventional devices has various inconveniences, especially when targeting a large-sized work, and is inexpensive as an auxiliary agent for collecting water. By using a water adsorbent, it is possible to reliably adsorb water under a large flow rate of gas, and to enable direct weighing with a direct balance, realizing a reliable and quick water measurement with a simple structure. The purpose is to achieve.

(Means for Solving the Problems) However, as is clear from the drawings showing the embodiments of the present invention, the direct balance (1) fixed to the pedestal (2), the gas outlet (4A) and the gas are shown. Enclose the water adsorbent (5) in a container having one side with the inlet (4B) at the top and the other side at the bottom,
Moisture adsorber (4) suspended from under-floor weighing hook (3) of direct balance (1) through suspending metal fitting (6), and the stand without contact with moisture adsorber (4) The moisture measuring device is configured from the outer casing (7) fixed to (2).

In the present invention, the outer casing (7) further has a hole (14) having a diameter smaller than that of the top plate of the water adsorber (4), and the metal fitting (6) for the water adsorber (4) is provided in the hole (14). And a tube portion (9) which is loosely inserted through a connecting portion with and a cylindrical portion (9) which is airtightly encircled around the moisture adsorber (4) and fixed to the ceiling plate (8). And a sealing material (1) capable of hermetically sealing the periphery of the hole (14) at a position where either the top plate (8) or the top plate of the moisture adsorber (4) can come into surface contact with each other.
3) The sample gas introduction part (11) or the derivation part (12) is located at the lower end of the cylindrical part (9) of the outer casing (7) and the sample gas derivation part (12) or the introduction part is attached. The sleeve (1) is provided with the (11) holes at the upper part thereof, and the sample gas flow pipe (15) to be inserted into the sample gas introducing part (11) or the outlet part (12) formed at the lower end part is fitted therein.
(0) is built into the tubular part (9), and the sleeve (1
0) is provided so as to be airtight with respect to the inner wall of the tubular part (9) and slidable in the axial direction of the tubular part, and its upper end rim can be brought into contact with the peripheral edge of the bottom part of the water adsorber (4). With the sample gas flow pipe (15) being pushed upward, the sample gas introduced from the sample gas introduction part (11) is fed from the gas inlet (4B) of the moisture adsorber (4) to the moisture adsorbent. It is characterized in that it can be led out from the gas outlet (4A) of the moisture adsorber (4) through the sample gas outlet (12) through the layer (5).

(Function) In the present invention, when the sample gas is sampled, the sample gas flow pipe (15) is pushed upward into the cylindrical portion (9) of the outer casing (7) as much as possible, so that the sleeve (10) is pushed.
When the moisture adsorber (4) is pushed up via the, the top plate of the moisture adsorber (4) is pressed against the top plate (8) of the outer casing (7) via the sealing material (13). The cylindrical portion (9) that forms a sealed container that is disconnected from the atmosphere, so that the sample gas introduced from the sample gas introduction unit (11) is introduced into the gas inlet (4B) of the moisture adsorber (4). ) From the water adsorbent (5) layer, and is led out from the gas outlet (4A) of the water adsorber (4) via the sample gas outlet (12), so that the entire sample gas is the water adsorber (4). After passing through the water adsorbent (5) layer therein, water is adsorbed in the layer and then led out through the sample gas outlet (12).

Thus, the water in the sample gas is completely collected without fail in the water adsorber (4).

In this state, since the moisture adsorber (4) and the direct indication balance (1) are separated from each other, the direct indication balance (1) can be used as an ordinary balance.

When the above-mentioned sampling is completed, the sample gas flow pipe (15) is pulled out downward and the sleeve (10) is moved down to the stopper contacting position at the lower side, and the moisture adsorber (4) comes into contact with the outer casing (7). Since it is in a suspended state without doing so, the weight of the moisture adsorber (4) that has adsorbed moisture is directly applied to the upper plate of the direct balance (1).

Therefore, the direct weighing of the moisture adsorber (4) can be easily performed,
The water content can be easily calculated by obtaining the difference from the value weighed before adsorption.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 6.

In FIG. 3 and FIG. 4, (1) is a general-purpose direct balance having four columns (2-A) ...
A) an upper plate (2-B), a lower plate (2-C), and a lower plate (2-C) that are laterally bridged between the upper end portions and the lower end portions of
It is mounted and fixed on a pedestal (2) having an underfloor weighing hook (3) vertically from a tray receiver (not shown) that supports an upper tray for weighing, and the upper plate (2-B) is attached. It is hanging and hanging.

The mount (2) has an intermediate plate (2-E) which is horizontally supported by four bolts (2-D) ... The outer casing (7) is hung down and fixed to the intermediate plate (2-E) in an arrangement coaxial with the hook (3).

The outer casing (7) is, as shown in detail in FIGS. 1 and 2, a top plate (8) fitted and fixed to the intermediate plate (2-E).
And a cylinder portion (9) that is a butt joint of the upper half cylinder (9_A) and the lower half cylinder (9_B), and by tightening the top plate (8) with the bolt (25), Upper half cylinder (9-
A) is airtightly fixed, and the upper half cylinder (9-A) and the lower half cylinder (9
-B) is airtightly coupled to form a housing having an airtight integral structure.

In this outer casing (7), the lower half opening (9-B) of the lower half cylinder (9-B) serves as a sample gas introduction part (11), and the upper half cylinder (9-A).
Has a hole formed in the upper cylindrical wall of the sample gas outlet (12), and has a smaller diameter in the center of the top plate (8) than the top plate of the moisture adsorber (4) described later. Hole made (1
4) is drilled.

Inside the outer casing (7) having the above-mentioned structure, the moisture adsorber (4) and the sleeve (10) are incorporated, and the moisture adsorber (4) forms a top-bottomed cylinder, The top plate is formed into a lid shape in which a connecting portion for hooking to the above-mentioned underfloor weighing hook (3) and connecting to a rod-shaped hanging metal fitting (6) that is hung is projected upward, and a cup shape is added to this. The main body of the eggplant is fitted and fixed to form a container with an integral structure. An air circulation port with a wire mesh is provided on the bottom wall and the upper part of the peripheral wall, and the gas inlet (4B) of the moisture adsorber (4) is provided. ) And a gas outlet (4A).

The moisture adsorber (4) is integrally assembled after removing the top plate from the cylinder body and enclosing the moisture adsorbent (5) in the cylinder body, and the hanging metal fitting (6) as shown in FIG. 1 and the like. It is hung from the underfloor weighing hook (3) through the above, but in this suspended state, it does not come into contact with the outer casing (7) and is surrounded by the outer casing (7) in an airtight manner. That is, it will be built in the outer casing (7).

As the water adsorbent (5), molecular sieves commonly referred to as synthetic zeolite can be cited as preferable ones.

For example, in the case of pellets of Molecular Sieves 3A, the water of crystallization is released by heating to become a porous adsorbent,
These pores have a number of uniform diameters, produce a molecular sieving effect, and have the property of reversibly easily absorbing moisture to restore water of crystallization, and have an equilibrium adsorption amount of 20% by weight equivalent. It is known to adsorb an amount of water.

On the other hand, the sleeve (10) is formed into a stepped cylinder,
Prior to assembling the upper half cylinder (9-A) and the lower half cylinder (9-B), the upper half cylinder (9-A) can be inserted inside the cylinder.
-A) and the lower half cylinder (9-B) are slidably contacted with each other to maintain airtightness and are movable in the cylinder axial direction, and the upper end rim of the cylinder of the moisture adsorber (4) is provided. It has an appropriate diameter so that it can contact the peripheral edge of the bottom.

The lower end opening of the sleeve (10) is formed as a connection port into which a sample gas flow pipe (15), for example, a sample gas introduction pipe (15) is hermetically fitted. In order to ensure reliable connection, it is a suitable means to perform processing such as engraving an internal thread on the inner wall of the lower end opening.

In order to prevent the sleeve (10) from coming out of the outer casing (7), a stopper wall that can come into contact with the outer casing (7) at the lower limit position apart from the water adsorber (4) is provided in the outer casing (7). It is a thing.

Therefore, in FIGS. 1 and 2, (13) is a sealing material, for example, an O-ring, which is inserted in a ring groove formed on the upper surface side of the top plate of the water adsorber (4), and the water adsorber (13) When the top plate is brought into surface contact with the top plate (8) of the outer casing (7) by pushing up 4), the surface contact portion around the hole (14) can be hermetically sealed.

In addition to the attachment of the sealing material (13) to the top plate,
Of course, it does not matter if it is attached to the lower surface side of the top plate (8) of the outer casing (7).

Insert the tube end of the sample gas introduction tube (15) into which the sample gas containing water is pumped by the water content measuring device having the structure described above into the sample gas introduction section (11),
While being fitted into the lower end opening of the sleeve (10),
Sample gas outlet pipe (16) in the sample gas outlet (12)
Connect.

When sampling the sample gas, push the sample gas introduction pipe (15) and push up the moisture adsorber (4) through the sleeve (10), and the sealing material (13) will move to the moisture adsorber (4). Since it is compressed by the top plate and the top plate (8) of the outer casing (7), the inner space of the outer casing (7) around the moisture adsorber (4) is completely cut off from the outside air.

This state is as shown in cross section in FIG.

Thus, the whole amount of the sample gas passes through the water adsorbent (5) layer in the water adsorber (4), so that the water is absorbed by the water adsorbent (5).
Is completely adsorbed on.

It should be noted that, in this sampling state, the hook (3) and the hanging metal fitting (6) can be in a free state without contacting each other. Therefore, if the weighing pan is used in this state, the direct balance (1 ) Can be used as an ordinary balance.

When moisture adsorption is completed and the weight of the moisture adsorber (4) is measured, if the sample gas introduction pipe (15) is pulled down and the sleeve (10) is moved down to the lower limit position,
The moisture adsorber (4) does not come into contact with the outer casing (7) and the sleeve (10) and is suspended by the hanging metal fitting (16) to be in a free state (see FIG. 1). ) Can be directly measured.

When replacing the water adsorbent (5), replace the bolt (2
When the tubular part (9) of the outer casing (7) is detached from the top plate (8) by loosening the (5), the moisture adsorber (4) is exposed, so that this can be removed to easily remove the moisture adsorbent (5). Can be replaced.

Next, an outline of a water content measuring system using the water content measuring device is shown in FIGS. 5 and 6. First, in the example shown in FIGS. 5 and 5, the inside of the workpiece (W) to be inspected is a gas pump (17). Sample gas outlet pipe (16) for circulating gas
Since the gas after adsorbing moisture through is dehumidified, there is an advantage that another dry gas is not required unlike the Karl-Fisher method.

For the gas pump (17), select a model such as a tire flam type that does not contaminate the sample gas. The device for heating the work (W) and the filter (19) are not always the required structure, but the type of the measured object. Select according to.

When the temperature of the sample gas flowing through the sample gas introduction pipe (15) becomes higher than room temperature, the water adsorbent (5) in the water adsorber (4) rises in temperature and the adsorbing ability is lowered. 18) is installed on the introduction line side as needed.

On the other hand, the example shown in FIGS. 6A and 6B is a vacuum attraction system, and is a system applied to a system in which gas circulation is difficult inside the work (W).

When the flow rate exhausted by the vacuum pump (20) is higher than necessary, water may be discharged without being adsorbed by the moisture adsorber (4), so the exhaust rate is adjusted by the flow rate adjustment valve (23), etc. I am trying to do it.

Further, in order to prevent backflow, a surge tank (21), a solenoid valve (22) operated by a vacuum switch (24), and the like are provided and controlled.

The heating device, the heat radiation device (18), and the filter (19) are selected as needed, as in the example shown in FIG.

(Effects of the Invention) In the present invention, when moisture is measured, a gas containing moisture is circulated in the moisture adsorbent (5) layer in the moisture adsorber (4) to collect moisture by adsorption. Therefore, by selecting the type and amount of the water adsorbent (15), it is possible to easily and quickly measure even a gas flow rate that is considerably large, and the measurement time can be shortened. It is expected that productivity will be improved by improving the efficiency of sampling inspection.

Further, according to the present invention, the switching between the moisture collection by adsorption and the moisture measurement after the collection is provided in the sleeve (1) provided in the outer casing (7).
It only needs to be moved up and down in (0) and the handling is extremely simple. Moreover, since the water content is measured directly by the direct balance (1), it can be measured easily and accurately.

Further, since the direct structure balance (1), the moisture adsorber (4), and the outer casing (7) are simple structures, the device cost required for measurement is low, and it is suitable as a general-purpose device. .

[Brief description of drawings]

1 and 2 are sectional views showing the structure of the essential part of one embodiment of the present invention at the time of weighing and at the time of sample sampling, respectively.
FIGS. 4 and 5 are a left side view and a front view according to an example of the measuring device of the present invention, FIGS. 5 and 6 are schematic views of respective moisture measuring systems according to an embodiment of the present invention, FIG. 7 and FIG. FIG. 8 is a schematic diagram of two examples of conventional moisture measurement systems. (1) …… Direct balance, (2) …… Stand, (3) …… Underfloor weighing hook, (4) …… Moisture absorber, (4A) …… Gas outlet, (4B) …… Gas inlet, (5) …… Water adsorbent,
(6) …… Suspension fittings, (7) …… Outer casing, (8) …… Top plate, (9) …… Cylinder, (10) …… Sleeve, (11) ……
Sample gas inlet, (12) …… Sample gas outlet,
(13) …… Seal material, (14) …… Hole, (15) …… Sample gas flow pipe,

Claims (1)

[Claims] 1. A direct balance (1) fixed to a pedestal (2).
And the water adsorbent (5) is enclosed in a container having one of the gas outlet (4A) and the gas inlet (4B) at the top and the other at the bottom, and the hook for underfloor dispensing of the direct balance (1). A water adsorber (4) suspended from the water adsorption device (4) via a hanging metal fitting (6) and a hole (14) having a diameter smaller than that of the top plate of the water adsorber (4) are provided in the hole (14). The top plate (8) loosely inserted through the connecting portion of the moisture adsorber (4) to the hanging metal fitting (6) and the moisture adsorber (4) are airtightly surrounded and fixed to the top plate (8). And an outer casing (7) which is formed by the cylindrical portion (9) and is fixed to the pedestal (2) while maintaining a non-contact state with the moisture adsorber (4). A sealing material (13) capable of hermetically sealing the periphery of the hole (14) is attached to a portion of either the top plate or the top plate (8) of the outer casing (7) that can be in surface contact with each other. On the other hand, in the tubular portion (9) of the outer casing (7), one of the sample gas introducing portion (11) and the sample gas outlet portion (12) is provided at the lower end and the other is provided at the upper portion. A sleeve (10) into which a sample gas flow pipe (15) to be inserted into a sample gas lead-in / out portion formed at the lower end is fitted is built in the tubular portion (9), and the sleeve (10) is placed in the tubular portion. The sample gas flow pipe is provided so as to be airtight with respect to the inner wall of (9), slidable in the cylinder axis direction, and capable of abutting its upper end rim against the bottom peripheral edge of the water adsorber (4). The sample gas introduced from the sample gas introduction part (11) with the (15) pushed upward is fed from the gas inlet (4B) of the moisture adsorber (4) to the moisture adsorbent (5) layer. Through the gas outlet (4A) of the moisture adsorber (4) Part (12) moisture measuring apparatus characterized by comprising obtained derived through.