JPS6041972B2 - How to detect filter clogging - Google Patents

How to detect filter clogging

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Publication number
JPS6041972B2
JPS6041972B2 JP52073500A JP7350077A JPS6041972B2 JP S6041972 B2 JPS6041972 B2 JP S6041972B2 JP 52073500 A JP52073500 A JP 52073500A JP 7350077 A JP7350077 A JP 7350077A JP S6041972 B2 JPS6041972 B2 JP S6041972B2
Authority
JP
Japan
Prior art keywords
filter
pressure
clogging
filter element
fluid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
JP52073500A
Other languages
Japanese (ja)
Other versions
JPS549066A (en
Inventor
隆司 鈴木
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
IHI Corp
Original Assignee
IHI Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by IHI Corp filed Critical IHI Corp
Priority to JP52073500A priority Critical patent/JPS6041972B2/en
Publication of JPS549066A publication Critical patent/JPS549066A/en
Publication of JPS6041972B2 publication Critical patent/JPS6041972B2/en
Expired legal-status Critical Current

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Description

【発明の詳細な説明】 本発明はフィルタの目詰り検知方法に関する。[Detailed description of the invention] The present invention relates to a filter clogging detection method.

流体中の汚染物質、固形物、粘稠物等のゴミを分離する
方法として流体を濾布、金網、スポンジ等のフィルタエ
レメントを通過せしめてゴミを捕捉する方法がある。
従来、フィルタのゴミ捕獲量検出方法としてはフィルタ
エレメント前後の圧力または圧力差を検出し、圧力差が
フィルタエレメントの耐圧力差に比しどの程度の割合で
あるかを機械的に指示するのが一般である。
BACKGROUND ART As a method for separating contaminants, solid matter, viscous matter, and other contaminants in a fluid, there is a method of passing the fluid through a filter element such as a filter cloth, a wire mesh, or a sponge to trap the contaminants.
Conventionally, the method for detecting the amount of dust captured by a filter is to detect the pressure or pressure difference before and after the filter element, and mechanically indicate the ratio of the pressure difference to the withstand pressure difference of the filter element. General.

例えば、第1図で示す如くフィルタケース1内に収容し
たフィルタエレメント2をはね3により下方向へ押付け
て成り、流体を流体入口4より流入せしめてフィルタエ
レメント2を通過させ、流体出口5より流出せしめるフ
ィルタ装置がある。該装置はフィルタエレメント2にゴ
ミが捕捉されるとフィルタ抵抗が大きくなり第2図で示
す如くばね3を縮小するようにフィルタエレメント2が
上方向へ移動し、さらに第3図で示す如くフィルタエレ
メント2の移動量を、フィルタエレメント2と連動する
レバー6、レバー6と連結された指針軸7および指針軸
7に取り付けられた指針、8で外部に表示する、すなわ
ち、レバー6の揺動で指針8が旋回してフィルタケース
1に設けた目詰り表示板9を指示して目詰りの程度を表
わす目詰り検知装置を備えている。 しかし、流体が粘
性流の場合フィルタの抵抗は粘度により異なり、また流
量によつても異なるものであり、上述したフィルタ装置
の目詰り検知装置は流量変化、流体粘度変化を圧力差の
バラメータとして区別しないためゴミ捕捉状況を誤つて
指示することがあり、信頼性を持ち得ず、ときには目詰
りが大きくなり圧力が増大してフィルタエレメントが破
損することがある。
For example, as shown in FIG. 1, a filter element 2 housed in a filter case 1 is pressed downward by a spring 3, and fluid is caused to flow in from a fluid inlet 4 and pass through the filter element 2, and then from a fluid outlet 5. There is a filter device that allows the water to flow out. In this device, when dust is trapped in the filter element 2, the filter resistance increases, and the filter element 2 moves upward to contract the spring 3 as shown in FIG. 2 is displayed externally by a lever 6 that interlocks with the filter element 2, a pointer shaft 7 connected to the lever 6, and a pointer 8 attached to the pointer shaft 7. 8 is provided with a clogging detection device which rotates to indicate the degree of clogging by indicating a clogging display plate 9 provided on the filter case 1. However, when the fluid is a viscous flow, the resistance of the filter differs depending on the viscosity and also the flow rate, and the above-mentioned clogging detection device of the filter device distinguishes between changes in flow rate and changes in fluid viscosity as pressure difference parameters. This may result in incorrect indications of the dirt capture status, unreliability, and sometimes even greater clogging and increased pressure that may damage the filter element.

そこで、本発明は流体流量、流体粘度をもパラメータ
に組込んで圧力換算し、精度の高いゴミ捕捉量の指示を
可能とし、省力化、装置のメンテナンス、フリー化に役
立ち、またフィルタエレメントの破損を未然に防止でき
るフィルタの目詰り検知方法を提供するものてある。
Therefore, the present invention incorporates fluid flow rate and fluid viscosity into parameters and converts them into pressure, making it possible to indicate the amount of dust captured with high accuracy, which is useful for labor saving, equipment maintenance, and free operation, and also prevents damage to the filter element. There is a method for detecting filter clogging that can prevent such problems from occurring.

本発明の方法によれば、流体の温度からそのときの粘性
係数を算出し、該粘性係数とフィルタを流通する流量か
らフィルタが全く目詰りしていないときの該フィルタに
おける定格抵抗差圧ΔPを第2計算要素で算出し、さら
に流通時のフィルタの入口側の圧力P1と出口側の圧力
P2と前記抵抗差圧ΔPとからフィルタの目詰りによる
増加分の抵抗差圧P=(P1−P2)−ΔPを算出する
ことによりフィルタのの目詰り状態を検知するものであ
る。
According to the method of the present invention, the viscosity coefficient at that time is calculated from the temperature of the fluid, and the rated resistance differential pressure ΔP in the filter when the filter is not clogged at all is calculated from the viscosity coefficient and the flow rate flowing through the filter. Calculated by the second calculation element, and further calculated from the pressure P1 on the inlet side of the filter, the pressure P2 on the outlet side, and the resistance differential pressure ΔP during circulation, the increased resistance differential pressure P due to filter clogging = (P1 - P2 )-ΔP to detect the clogging state of the filter.

以下、本発明のフィルタの目詰り検知方法の実施例を第
4図を参照して説明する。
Hereinafter, an embodiment of the filter clogging detection method of the present invention will be described with reference to FIG.

フィルターケース10内には紙、繊維、金網、あるいは
スポンジ等を有底筒形に形成したフィルタエレメント1
1が取付けられており、流体はフィルターケース10に
開設した入口12から流入しフィルタエレメント11の
周囲に流れ、流体中の汚染物質、固形物、粘稠物等のゴ
ミがフィルタエレメント11に捕捉され、濾過された流
体が筒形のフィルタエレメント11を通るように流れフ
ィルタケース10に開設した出口13から流出するよう
構成されている。前記フィルタの入口12に臨んで流入
側圧力検出器14が取付けられ、またフィルタの出口1
3に臨んで流出側圧力検出器15と流量検出器16と流
体温度検出器17がそれぞれ取付けられている。特に、
本発明ではフィルタの目詰り状態を検知するため計算機
構18を備えており、該計算機構18は第1計算要素1
9と第2計算要素20と第3計算要素21とから構成さ
れており、第1計算要素19は、前記流体温度検出器1
7で検出された温度Tを電気信号として入力して該検出
温度にもとつき流体の粘性係数νを電気信号として演算
するものであり、第2計算要素20は、前記第1計算要
素19で算出した流体の粘性係数の電気信号と前記流量
検出器16で検出されて入.力された流量Qの信号とに
よりフィルタエレメント11が全く目詰りしていないと
きの該フィルタエレメントにおける定格抵抗差圧ΔPを
電気信号として演算するものであり、第3計算要素21
は、前記流入側圧力検出器14で検出された圧力,P1
の信号と前記流出側圧力検出器15で検出された圧力P
2の信号と前記第2計算要素20で算出されたフィルタ
エレメントにおける定格抵抗差圧ΔPの信号とをそれぞ
れ入力して流体流通時におけるフィルタの目詰りによる
増加分の抵抗差圧P=(P1−P2)−ΔPを電気信号
として比較減算するものである。また上記第3計算要素
21で算出された抵抗差圧Pの電気信号は、発光ダイオ
ード等の表示器22においてデジタル表示されると共に
、記録装置23で電気信号が経時的に記録され装置停止
時も情報が得られるようにし、さらにインターフェイス
、あるいは変換器24に抵抗差圧Pの電気信号を入力し
て他の機器に伝え得られるようlにする。なお、上記イ
ンターフェイスあるいは変換器24により与えられる信
号でフィルタを流れる流体の流れ方向を逆方向にしてフ
ィルタエレメント11に捕捉されたゴミを離脱洗滌でき
るような回路機能を組むことも可能である。したがつて
、フィルタエレメント11が全く目詰りしていないとき
は、流入側圧力検出器14と流出側圧力検出器15とか
ら検出できるフィルタエレメントの差圧はP1−P2で
あり、この差圧P1一P2は粘性係数νと流量Qとから
第2計算要素20・で算出されるΔPと等しくなり、第
3計算要素21ではフィルタエレメント11に発生する
抵抗のうち目詰りによる圧力上昇分Pは算出されず、こ
れによりフィルタエレメント11が目詰りしていないこ
とを検知できる。
Inside the filter case 10 is a filter element 1 formed of paper, fiber, wire mesh, sponge, etc. into a cylindrical shape with a bottom.
1 is attached, fluid flows in from an inlet 12 opened in the filter case 10 and flows around the filter element 11, and dirt such as pollutants, solids, and viscous substances in the fluid is captured by the filter element 11. The filtered fluid flows through the cylindrical filter element 11 and exits from an outlet 13 provided in the filter case 10. An inflow side pressure detector 14 is installed facing the inlet 12 of the filter, and an inlet side pressure detector 14 is installed facing the inlet 12 of the filter.
3, an outflow side pressure detector 15, a flow rate detector 16, and a fluid temperature detector 17 are installed, respectively. especially,
In the present invention, a calculation mechanism 18 is provided to detect the clogging state of the filter, and the calculation mechanism 18 is connected to the first calculation element 1.
9, a second calculation element 20, and a third calculation element 21, and the first calculation element 19
The temperature T detected in step 7 is input as an electrical signal and the viscosity coefficient ν of the fluid is calculated based on the detected temperature as an electrical signal. The electric signal of the calculated viscosity coefficient of the fluid and the input signal detected by the flow rate detector 16 are input. The third calculation element 21
is the pressure detected by the inflow side pressure detector 14, P1
signal and the pressure P detected by the outflow side pressure detector 15
2 and the signal of the rated resistance differential pressure ΔP in the filter element calculated by the second calculation element 20, respectively, and calculate the increased resistance differential pressure P=(P1− P2) - ΔP is compared and subtracted as an electrical signal. Further, the electrical signal of the resistance differential pressure P calculated by the third calculation element 21 is digitally displayed on a display 22 such as a light emitting diode, and the electrical signal is recorded over time in a recording device 23, even when the device is stopped. In addition, the electrical signal of the resistance differential pressure P is input to the interface or converter 24 so that the information can be transmitted to other equipment. It is also possible to construct a circuit function in which the flow direction of the fluid flowing through the filter is reversed by the signal given by the interface or the converter 24, so that the dust trapped in the filter element 11 can be removed and washed. Therefore, when the filter element 11 is not clogged at all, the differential pressure across the filter element that can be detected by the inlet pressure detector 14 and the outlet pressure detector 15 is P1-P2, and this differential pressure P1 -P2 is equal to ΔP calculated by the second calculation element 20 from the viscosity coefficient ν and the flow rate Q, and the third calculation element 21 calculates the pressure increase P due to clogging out of the resistance generated in the filter element 11. Therefore, it can be detected that the filter element 11 is not clogged.

またフィルタエレメント11力泪詰りを起したような場
合には、圧力検出器14,15の差圧P1−P2は大き
くなるがΔPは流体温度Tおよび流量Qが一定であれば
変化することがなく、フィルタエレメント11の目詰り
によつて生ずる増加分の差圧P=(P1−P2)−ΔP
であることが第3計算要素21で算出され、目詰りによ
る圧力上昇を知ることができ、フィルタエレメント11
の目詰りが証明される。また流体温度Tおよび流量Qが
変化すればΔPも変化するがこれに対応してP1−P2
も等しく変化するのでフィルタエレメント11の目詰り
によつて生ずる増加分の差圧は常にP=(P1−P2)
−ΔPである。上述の実施例において圧力検出器14,
15は、フィルタケースに直接に取付ける必要はなく、
また他の手段により圧力が検出され電気信号に変換され
るものでもよい。また、流出側が大気圧に開放されてい
るりタンフィルタでは上述の流出側圧力検出器15を組
込ます、大気圧の条件を電気信号として第3計算要素2
1に入力すればよい。定流量吐出ポンプを用いる場合は
流量を計測する必要がないので、流量検出器16を設け
ず、流量に対応する電気信号を第2計算要素20に入力
すればよい。また、第1計算要素19は使用流体の温度
と粘度との関係は関数として予め与えておき、流体温度
検出器17によつて温度Tを検出され変換された電気信
号を入力することによりその温度Tにおける粘性係数ν
に対応した電気信号を出力できるようにしておく、同様
に第2計算要素20は粘度νおよび流量Qとフィルタエ
レメントの目詰りしていないときの差圧ΔPとの関係を
予め計測してデータとして与えておくかあるいは計測結
果に基く関係式ΔP=Kf(Q,ν)として与えておき
、変換された温度Tの電気信号および流量Qの電気信号
を入力することにより差圧ΔPを演出できるようにして
おく。また、第3計算要素21は必要に応じΔPの電気
信号をカットすればP1−P2の電気信号のみ、すなわ
ちフィルタエレメントにおける全抵抗を検知できるもの
とする。なお、上述の実施例は1個のフィルタに対する
目詰り検出方法について述べたが、本発明の方法ノは多
数個のフィルタを1個の計算機構により入力を切替える
ことにより目詰り検出するいわゆるマルチループ処理も
広く含むものである。また、フィルタエレメントの使用
し得る最大差圧は予め計測できるので、本発明の方法は
フイルタエレメンントの使用可能な最大差圧または目詰
り量を示すことも広く含んている。上述のように構成し
た本発明のフィルタの目詰り検知方法は次のような効果
がある。
Furthermore, if the filter element 11 is clogged, the differential pressure P1-P2 between the pressure detectors 14 and 15 will increase, but ΔP will not change as long as the fluid temperature T and flow rate Q are constant. , increased differential pressure P=(P1-P2)-ΔP caused by clogging of filter element 11
It is calculated by the third calculation element 21 that the pressure increase due to clogging can be known, and the filter element 11
clogging is proven. Also, if the fluid temperature T and flow rate Q change, ΔP also changes, but P1-P2
also change equally, so the increased differential pressure caused by clogging of the filter element 11 is always P = (P1 - P2)
−ΔP. In the embodiments described above, the pressure sensor 14,
15 does not need to be installed directly on the filter case,
Alternatively, the pressure may be detected by other means and converted into an electrical signal. In addition, in the case of a filter whose outflow side is open to atmospheric pressure, the above-mentioned outflow side pressure detector 15 is incorporated, and the third calculation element 2 uses the atmospheric pressure condition as an electrical signal.
Just enter it in 1. When a constant flow discharge pump is used, there is no need to measure the flow rate, so the flow rate detector 16 may not be provided, and an electrical signal corresponding to the flow rate may be input to the second calculation element 20. Further, the first calculation element 19 calculates the relationship between the temperature and viscosity of the fluid used in advance as a function, and calculates the temperature by inputting the electric signal that is detected by the fluid temperature detector 17 and converted. Viscosity coefficient ν at T
Similarly, the second calculation element 20 measures in advance the relationship between the viscosity ν, the flow rate Q, and the differential pressure ΔP when the filter element is not clogged, and outputs the data as data. The differential pressure ΔP can be produced by inputting the electrical signal of the converted temperature T and the electrical signal of the flow rate Q. Keep it. Further, it is assumed that the third calculation element 21 can detect only the electrical signal of P1-P2, that is, the total resistance in the filter element, by cutting the electrical signal of ΔP as necessary. In addition, although the above-mentioned embodiment described the clogging detection method for one filter, the method of the present invention is a so-called multi-loop method in which clogging is detected by switching the inputs of a large number of filters using one calculation mechanism. It also broadly includes processing. Additionally, since the maximum usable differential pressure of the filter element can be measured in advance, the method of the present invention broadly includes indicating the maximum usable differential pressure or amount of clogging of the filter element. The filter clogging detection method of the present invention configured as described above has the following effects.

(1)流体流量と流体粘度とを検出して、これによ!り
フィルタエレメントが全く日詰りしていないときの差圧
ΔPを算出するとともにフィルタエレメントの流入側と
出口側との実圧力差P1−P2を検出し、これらよりフ
ィルタエレメントが目詰りした時の増加分の差圧P=(
P1−P2)−Δ3Pを検出するものであるから、流体
流量、流体粘度をもパラメータとして組込むことになり
精度の高いゴミ捕捉量の指示が可能となり、信頼性が向
上する。
(1) Detect the fluid flow rate and fluid viscosity and use this! In addition to calculating the differential pressure ΔP when the filter element is not clogged at all, the actual pressure difference P1-P2 between the inflow side and the outlet side of the filter element is detected, and from these, the increase when the filter element is clogged is calculated. differential pressure P=(
Since it detects P1-P2)-Δ3P, the fluid flow rate and fluid viscosity are also incorporated as parameters, making it possible to indicate the amount of trapped dust with high accuracy, and improving reliability.

(9)電気信号として差圧を算出するものてあり、記録
計の接続が可能となるので、流体が流れていなくても記
録計を見れば目詰り量がわかる。
(9) There is a device that calculates the differential pressure as an electrical signal, and a recorder can be connected, so the amount of clogging can be determined by looking at the recorder even when fluid is not flowing.

(Iii)予めフィルタ抵抗と目詰り状態との相関をを
計測しておけば、目詰り状態を知ることができ、ひいて
はゴミの量として示すことができ、フィルタエレメント
を交換すべき状態にあるか否かを正確に指示できる。(
Iv)機械式のフィルタの目詰り検知装置はヒステリシ
スによる誤差が多いが、本発明の方法は電気的方法であ
るから指示精度が向上する。
(iii) By measuring the correlation between the filter resistance and the clogging state in advance, it is possible to know the clogging state, which can also be indicated as the amount of dust, and whether the filter element needs to be replaced. You can accurately indicate whether or not. (
Iv) Mechanical filter clogging detection devices have many errors due to hysteresis, but since the method of the present invention is an electrical method, the accuracy of indication is improved.

(v)記録計を接続すれば、一定期間をとらえ、フィル
タエレメントにおける差圧上昇がわかり、目詰りの進行
状態がわかる。
(v) If a recorder is connected, the increase in differential pressure in the filter element can be detected over a certain period of time, and the progress of clogging can be determined.

(v1)フィルタの使用し得る最大流量を既知とすれば
、その時の流体の粘度がフィルタエレメントを破損する
程圧力が高くなつているかどうか、またフィルタエレメ
ント破損を防止するためにリリーフ弁が組込まれている
場合にはリリーフ弁が作動しゴミが下流側に流れる状態
までの圧力の余裕を知ることができる。
(v1) If the maximum flow rate that the filter can use is known, the viscosity of the fluid at that time is such that the pressure is high enough to damage the filter element, and whether a relief valve is installed to prevent damage to the filter element. If it is, you can know how much pressure there is until the relief valve is activated and the debris flows downstream.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図ないし第3図は従来例のフィルタの機械式目詰り
検知装置に係り、第1図はフィルタが目詰りしていない
ときのフィルタ装置の断面図、第2図はフィルタが目詰
りしたときのフィルタ装置の断面図、第3図はフィルタ
と目詰り検知装置部分との関係を示す斜視図、第4図は
本発明のフィルタの目詰り検知方法の実施例に係る説明
図である。 11はフィルタエレメント、1!は第1計算要素、20
は第2計算要素、21は第3計算要素。
Figures 1 to 3 relate to a conventional mechanical filter clogging detection device. Figure 1 is a cross-sectional view of the filter device when the filter is not clogged, and Figure 2 is a cross-sectional view of the filter device when the filter is clogged. FIG. 3 is a perspective view showing the relationship between the filter and the clogging detection device, and FIG. 4 is an explanatory diagram of an embodiment of the filter clogging detection method of the present invention. 11 is a filter element, 1! is the first calculation element, 20
is the second calculation element, and 21 is the third calculation element.

Claims (1)

【特許請求の範囲】[Claims] 1 フィルタを流通する流体の温度を検出し、該検出温
度における流体の粘性係数を第1計算要素で算出し、該
粘性係数とフィルタを流通する流体の流量とからフィル
タエレメントが全く目詰りしていないときの該フィルタ
エレメントにおける定格抵抗差圧ΔPを第2計算要素で
算出し、さらに流体流通時のフィルタの入口側の圧力P
_1とフィルタの出口側の圧力P_2と前記第2計算要
素で算出したフィルタエレメントの定格抵抗差圧ΔPと
からフィルタエレメントの目詰りによる増加分の抵抗差
圧P=(P_1−P_2)−ΔPを第3計算要素で算出
することによりフィルタの目詰り状態を検知することを
特徴とするフィルタの目詰り検知方法。
1. Detect the temperature of the fluid flowing through the filter, calculate the viscosity coefficient of the fluid at the detected temperature using the first calculation element, and determine whether the filter element is completely clogged based on the viscosity coefficient and the flow rate of the fluid flowing through the filter. The rated resistance differential pressure ΔP in the filter element when the filter element is not present is calculated using the second calculation element, and the pressure P on the inlet side of the filter when fluid flows is calculated.
From _1, the pressure P_2 on the outlet side of the filter, and the rated resistance differential pressure ΔP of the filter element calculated using the second calculation element, calculate the increased resistance differential pressure P=(P_1-P_2)-ΔP due to filter element clogging. A method for detecting clogging of a filter, comprising detecting a clogging state of the filter by calculating with a third calculation element.
JP52073500A 1977-06-21 1977-06-21 How to detect filter clogging Expired JPS6041972B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP52073500A JPS6041972B2 (en) 1977-06-21 1977-06-21 How to detect filter clogging

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP52073500A JPS6041972B2 (en) 1977-06-21 1977-06-21 How to detect filter clogging

Publications (2)

Publication Number Publication Date
JPS549066A JPS549066A (en) 1979-01-23
JPS6041972B2 true JPS6041972B2 (en) 1985-09-19

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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3835672A1 (en) * 1988-10-20 1990-04-26 Bayerische Motoren Werke Ag Process and apparatus for monitoring the degree of fouling of filters
JP6173534B1 (en) * 2016-06-23 2017-08-02 佐藤 厳一 Water treatment equipment
CN108007837B (en) * 2016-11-02 2020-09-11 财团法人车辆研究测试中心 Fluid filter abnormality detection method and fluid filter abnormality detection system
JP2020020397A (en) * 2018-07-31 2020-02-06 日立建機株式会社 Work machine

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JPS549066A (en) 1979-01-23

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