WO1994002772A1 - Leak detection for liquid hoses - Google Patents

Leak detection for liquid hoses Download PDF

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Publication number
WO1994002772A1
WO1994002772A1 PCT/US1993/006863 US9306863W WO9402772A1 WO 1994002772 A1 WO1994002772 A1 WO 1994002772A1 US 9306863 W US9306863 W US 9306863W WO 9402772 A1 WO9402772 A1 WO 9402772A1
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WO
WIPO (PCT)
Prior art keywords
hose
construction
color
color change
tubular wall
Prior art date
Application number
PCT/US1993/006863
Other languages
French (fr)
Inventor
T. Duc Doan
Original Assignee
Doan T Duc
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 Doan T Duc filed Critical Doan T Duc
Priority to AU47793/93A priority Critical patent/AU4779393A/en
Publication of WO1994002772A1 publication Critical patent/WO1994002772A1/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L11/00—Hoses, i.e. flexible pipes
    • F16L11/04—Hoses, i.e. flexible pipes made of rubber or flexible plastics
    • F16L11/12—Hoses, i.e. flexible pipes made of rubber or flexible plastics with arrangements for particular purposes, e.g. specially profiled, with protecting layer, heated, electrically conducting
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M3/00—Investigating fluid-tightness of structures
    • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
    • G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
    • G01M3/042—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point by using materials which expand, contract, disintegrate, or decompose in contact with a fluid
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
    • G01N31/22—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using chemical indicators

Definitions

  • This invention relates to liquid hoses, e.g. hoses used for circulating liquid coolants in internal combustion engines.
  • a principal aim of the invention is to incorporate into the hose a leak detector film that exhibits a color change in the presence of a leaking liquid condition.
  • the coolant circulation hoses in internal combustion engines have a black or dark gray outer surface. Should a leak develop along the hose or at clamped ends of the hose it becomes difficult to visually ascertain the leaking condition. The leaking liquid will appear merely at a darkened zone on the hose outer surface, such that an untrained person may mistakenly believe the darkened area is an oil spot or merely a localized color discontinuity in the hose coloration.
  • the present invention contemplates a leak detection film extending along the outer surface of a pressure-resistance hose, whereby liquid escaping through a crack in the hose reacts with the leak detection film to produce a visible color change.
  • a person viewing the hose after the hose has been de-pressurized can observe the changed color, and thus determine that the hose has a crack sufficient to produce a leak when the liquid is in a pressurized condition.
  • the outer surface of the hose is white, or some relatively light color, e.g. yellow or light blue.
  • the leak detection film will be a relatively thin film on the hose outer surface, whereby the film is normally essentially transparent or translucent, i.e. substantially visible. Should a leak develop in the hose wall or at the hose end surface the leaking liquid will chemically react with the leak detection film to produce a reaction product having a contrasting coloration to the light coloration of the hose outer surface.
  • the leak detection film can be chosen from among a number of substances, which possess the quality of changing colors when caused to chemically react with another liquid, e.g. a coolant or a coolant mixed with water to circulate in an automotive radiator system.
  • Cresolsulfonephthalein (Metacresol Purple) 7. Cresolsulfonephthalein : yellow : blue : 7.0-8.8 (Cresol Red)
  • the above-named chemicals directly change colors, as indicated, when brought in contact with e.g. a coolant or antifreeze with a pH of 10.
  • the coolant and antifreeze when mixed with water has a pH of 9.
  • the chemicals numbered 7 and 8 have a coloration reaction when changed into acid form, i.e. mixed with hydrochloric acid.
  • THE DRAWINGS Fig. 1 is a fragmentary side elevational view of a liquid circulation hose construction having a leak detection film on its outer surface, according to the present invention.
  • Fig. 2 is a sectional view taken on line 2-2 in Fig. 1.
  • the hose 10 formed primarily of an elastomeric material having flexibility and resilience for containment of the internal liquid pressure.
  • the hose is shown as a multi-ply tubular wall 11 having an outer surface 12 and an inner surface 14.
  • the outer surface of wall 11 has a film
  • Film 17 is comprised of solid particulates of a color change material adhered to surface 12 of the tubular wall by a coating of a transparent adhesive.
  • Film 19 is a transparent coating or outer band and applied to the exposed surface formed by the color change material.
  • Film 19 may be formed of a relatively thin colorless polythylene tape material wound helically on the tubular wall and heated to encapsulate the color change material 17.
  • the solid particulate color change material in film 17 may e.g. be any of the above-named chemicals or other material that undergoes a color change when brought into physical contact with the pressurized liquid, such as coolants or hydraulic fluids, leaking from within the hose structure.
  • Protective film 19 serves to shield the color change material from the external atmosphere during normal operational periods, whereby the color change material is prevented from being dislodged from the hose surface, e.g. by vibration, or from being contaminated by external direct accumulations. Should a leak develop the protective film 19 tends to retain the color change material on tube surface 12, thereby preserving the color change for later observation by the motorist mechanic.
  • the tube may first be sprayed or brushed with a thin film or contact adhesive.
  • the finely divided (powdered) color change material may then be sprayed as a thin essentially transparent film on the tacky tube surface 12.
  • the color change material will have a relatively small particle size so as to provide a thin coating that does not appreciably obscure the coloration of the tube outer surface.
  • Film 19 may be a thin transparent tape wound helically on the coated tube surface 12. As an alternative, film 19 could be formed by spraying or rolling the transparent protective materialy on the coated tube surface.
  • the invention was devised to provide a visible leak detection mechanism for hoses used to circulate liquid coolants within internal combustion engines, e.g. in automobiles or trucks.
  • coolants commonly comprise ethylene glycol in a dilute water solution (or emulsion) .
  • a hose coating for example of phenolphthalein will chemically react with the ethylene glycol with additives to produce a visible color change on the tube outer surface, i.e. from an essentially colorless condition to a red coloration or stain that contrasts with the light coloration on the hose surfaces not contacted by the escaping liquid.
  • the entire outer surface of the hose is coated with the color change material for example, phenolphthalein, which is an acid-base indicator used in chemical analyses.
  • the protective film 19 will completely encapsulate the color change material, including material on the hose end faces. Spraying may be used to apply film 19 to the material on the hose faces. However, it may be possible to apply, e.g. by means of a spray can, the color changing material after the user suspects that a leak in the hose has occurred, in which case the protective film 19 is eliminated. It is believed that the invention could be applied to other types of hoses carrying other types of liquid where leakage is a problem, e.g. gasoline hoses, liquid propane lines or hydraulic lines. The color change material would have to be selected with regard to its capability for undergoing a color change when brought into contact with the specific liquid being carried by the hose.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Biophysics (AREA)
  • Molecular Biology (AREA)
  • Mechanical Engineering (AREA)
  • Examining Or Testing Airtightness (AREA)

Abstract

A film (17) of color change material is formed on the outer surface (12) of a liquid-carrying hose (10) to provide a leak detection function. Should pressurized liquid leak through a crack in the hose (10) wall (11) (or at a loosely clamped end of the hose (10)) the detection material will react with the escaping liquid to provide a visible indication of leaking condition. One example of usage of the invention is on coolant circulation hoses (10) used in internal combustion engines; another usage is in a hydraulic system.

Description

LEAK DETECTION FOR LIQUID HOSES Background of the Invention
This invention relates to liquid hoses, e.g. hoses used for circulating liquid coolants in internal combustion engines. A principal aim of the invention is to incorporate into the hose a leak detector film that exhibits a color change in the presence of a leaking liquid condition.
Historically the coolant circulation hoses in internal combustion engines have a black or dark gray outer surface. Should a leak develop along the hose or at clamped ends of the hose it becomes difficult to visually ascertain the leaking condition. The leaking liquid will appear merely at a darkened zone on the hose outer surface, such that an untrained person may mistakenly believe the darkened area is an oil spot or merely a localized color discontinuity in the hose coloration.
Sometimes slow leaks can develop in the coolant-circulation hose. Pressurized liquid can seep through small cracks in the hose surface or around semi-loose hose clamps; when the engine is shut down the coolant pressure is reduced whereby the small cracks close up, so that the hose structure appears to be intact and leak-free.
The present invention contemplates a leak detection film extending along the outer surface of a pressure-resistance hose, whereby liquid escaping through a crack in the hose reacts with the leak detection film to produce a visible color change. A person viewing the hose after the hose has been de-pressurized can observe the changed color, and thus determine that the hose has a crack sufficient to produce a leak when the liquid is in a pressurized condition.
In a preferred form of the invention the outer surface of the hose is white, or some relatively light color, e.g. yellow or light blue. The leak detection film will be a relatively thin film on the hose outer surface, whereby the film is normally essentially transparent or translucent, i.e. substantially visible. Should a leak develop in the hose wall or at the hose end surface the leaking liquid will chemically react with the leak detection film to produce a reaction product having a contrasting coloration to the light coloration of the hose outer surface.
The leak detection film can be chosen from among a number of substances, which possess the quality of changing colors when caused to chemically react with another liquid, e.g. a coolant or a coolant mixed with water to circulate in an automotive radiator system.
A great number of chemicals was tested to determine their respective suitability for the intended purpose of the invention.
It was found that the following chemicals produced the desired results, according to the invention:
Name of Chemical
1. Phenolphthalein
2. Curcumin
3. Thymolphthalein 4. Cresolphthalein
5. Phenolsulfonephthalein
6. Cresolsulfonephthalein (Metacresol Purple)
Figure imgf000004_0001
7. Cresolsulfonephthalein : yellow : blue : 7.0-8.8 (Cresol Red)
8. Bromothymol Blue : yellow : blue : 6.0-7.6
The above-named chemicals, numbered 1 through 6, directly change colors, as indicated, when brought in contact with e.g. a coolant or antifreeze with a pH of 10. The coolant and antifreeze, when mixed with water has a pH of 9. The chemicals numbered 7 and 8 have a coloration reaction when changed into acid form, i.e. mixed with hydrochloric acid.
THE DRAWINGS Fig. 1 is a fragmentary side elevational view of a liquid circulation hose construction having a leak detection film on its outer surface, according to the present invention.
Fig. 2 is a sectional view taken on line 2-2 in Fig. 1.
DESCRIPTION OF A PREFERRED
EMBODIMENT OF THE INVENTION
The drawings fragmentarily show a pressure-resistant hose
10 formed primarily of an elastomeric material having flexibility and resilience for containment of the internal liquid pressure. The hose is shown as a multi-ply tubular wall 11 having an outer surface 12 and an inner surface 14. A wire cloth reinforcement
16 can be arranged between the inner and outer plies of the tubular wall. At least the outer ply of the tubular wall has a white or light coloration. As shown in Fig. 2, the outer surface of wall 11 has a film
17 of material thereon. A second protective film 19 is provided over film 17. Film 17 is comprised of solid particulates of a color change material adhered to surface 12 of the tubular wall by a coating of a transparent adhesive. Film 19 is a transparent coating or outer band and applied to the exposed surface formed by the color change material. Film 19 may be formed of a relatively thin colorless polythylene tape material wound helically on the tubular wall and heated to encapsulate the color change material 17. The solid particulate color change material in film 17 may e.g. be any of the above-named chemicals or other material that undergoes a color change when brought into physical contact with the pressurized liquid, such as coolants or hydraulic fluids, leaking from within the hose structure.
As the pressurized liquid comes into contact with the color changing material the latter undergoes a color change, e.g. from an essentially colorless or (pale yellow) condition to a red/blue/purple condition that contrasts sharply with the light coloration on other areas of outer surface 12 where there is no escaping the location of the leak for making temporary repairs, or replacement of the hose. Protective film 19 serves to shield the color change material from the external atmosphere during normal operational periods, whereby the color change material is prevented from being dislodged from the hose surface, e.g. by vibration, or from being contaminated by external direct accumulations. Should a leak develop the protective film 19 tends to retain the color change material on tube surface 12, thereby preserving the color change for later observation by the motorist mechanic.
In applying film 17 to the tube outer surface 12 the tube may first be sprayed or brushed with a thin film or contact adhesive. The finely divided (powdered) color change material may then be sprayed as a thin essentially transparent film on the tacky tube surface 12. The color change material will have a relatively small particle size so as to provide a thin coating that does not appreciably obscure the coloration of the tube outer surface. Film 19 may be a thin transparent tape wound helically on the coated tube surface 12. As an alternative, film 19 could be formed by spraying or rolling the transparent protective materialy on the coated tube surface.
The invention was devised to provide a visible leak detection mechanism for hoses used to circulate liquid coolants within internal combustion engines, e.g. in automobiles or trucks. Such coolants commonly comprise ethylene glycol in a dilute water solution (or emulsion) . A hose coating for example of phenolphthalein will chemically react with the ethylene glycol with additives to produce a visible color change on the tube outer surface, i.e. from an essentially colorless condition to a red coloration or stain that contrasts with the light coloration on the hose surfaces not contacted by the escaping liquid.
Preferably the entire outer surface of the hose (including the hose end faces) is coated with the color change material for example, phenolphthalein, which is an acid-base indicator used in chemical analyses. The protective film 19 will completely encapsulate the color change material, including material on the hose end faces. Spraying may be used to apply film 19 to the material on the hose faces. However, it may be possible to apply, e.g. by means of a spray can, the color changing material after the user suspects that a leak in the hose has occurred, in which case the protective film 19 is eliminated. It is believed that the invention could be applied to other types of hoses carrying other types of liquid where leakage is a problem, e.g. gasoline hoses, liquid propane lines or hydraulic lines. The color change material would have to be selected with regard to its capability for undergoing a color change when brought into contact with the specific liquid being carried by the hose.

Claims

CLAIMS I claim:
1. A hose (10) construction for a pressurized liquid, comprising a flexible tubular wall (11) having an inner surface (14) and an outer surface (12), said wall (11) being formed by a flexible resilient material subject to cracking over time, with consequent escape of the pressurized liquid; a film (17) of a color change material on the outer surface (12) of the tubular wall (11) , said color change material being capable of chemically changing color when it is brought into physical contact with the aforementioned pressurized liquid.
2. The hose (10) construction of claim 1, wherein a protective film (19) of transparent material overlying said color change material (17) is applied, so that the color change material (17) is physically isolated from the external atmosphere while being visible through the transparent protective film (17) .
3. The hose (10) construction of claim 1, wherein the outer surface (12) of the tubular wall (11) is relatively light opaque color, and the film (17) of color change material is sufficiently thin that the opaque coloring on the outer surface (12) of the tubular wall (11) determines the apparent coloration prior to chemical color change in the color change material.
4. The hose (10) construction of claim 3, wherein said color change material (17) is adhered to the outer surface (12) of the tubular wall (11) by means of a transparent adhesive.
5. The hose (10) construction of claim 3, wherein the tubular wall (11) constitutes a coolant hose (10) in an internal combustion engine, and the pressurized liquid is an anti- freeze solution containing ethylene glycol.
6. The hose (10) construction of claim 3, wherein the tubular wall (11) constitutes a hose (10) for a pressurized liquid in a hydraulic system.
7. The hose (10) construction of claim 1, wherein the color changing material comprises Phenolphthalein.
8. The hose (10) construction of claim 1, wherein the color changing material comprises Curcumin.
9. The hose (10) construction of claim 1, wherein the color changing material comprises Thymolphthalein.
10. The hose (10) construction of claim 1, wherein the color changing material comprises Cresolphthalein.
11. The hose (10) construction of claim 1, wherein the color changing material comprises phenolsulfanephthalein.
12. The hose (10) construction of claim 1, wherein the color changing material comprises Cresolsulfanephthalein (Metacresol Purple) .
13. The hose (10) construction of claim 1, wherein the color changing material comprises Cresolsulfanephthalein (Cresol Red) .
14. The hose (10) construction of claim 1, wherein the color changing material comprises Bromothymol Blue.
PCT/US1993/006863 1992-07-28 1993-07-15 Leak detection for liquid hoses WO1994002772A1 (en)

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US90099092A 1992-07-28 1992-07-28
US07/900,990 1992-07-28

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2307558A (en) * 1995-11-23 1997-05-28 Bosch Gmbh Robert Device for indicating leakage in hollow bodies which convey fluids
EP0859078A1 (en) * 1997-02-13 1998-08-19 Electrolux Zanussi S.p.A. Conduit for conveying a flow of fluid under pressure
NL1012596C2 (en) * 1999-05-12 2000-11-14 Pipelife Nederland Bv Protected plastic pipe for conveying liquid and/or gas, comprises liquid and/or gas tight inner plastic layer provided with outer plastic layer which is deformable plastically under influence of local load
DE10044039A1 (en) * 2000-09-07 2002-03-21 Brugg Rohrsysteme Gmbh Flexible pipeline comprises two concentric pipes with fleece layer in interspace between same and made of material to swell up when moisture enters
WO2003069298A1 (en) * 2002-02-12 2003-08-21 HÖRLIN, Emil, Oskar Device and method for detection/indication of liquid leakage
WO2005019816A1 (en) * 2003-08-20 2005-03-03 Honeywell International, Inc. Leak detection method using microencapsulated dye precursor
GB2410561A (en) * 2004-01-27 2005-08-03 David John Roughley Water leak detector
DE102011075998B3 (en) * 2011-05-17 2012-11-15 Simona Ag Container, tube or chemical apparatus with color indicator and composite semi-finished product with color indicator for the production of a container, tube or chemical apparatus
US8497309B2 (en) 2007-06-27 2013-07-30 H R D Corporation Gasification of carbonaceous materials and gas to liquid processes
CN103454047A (en) * 2012-05-28 2013-12-18 大自达电线株式会社 Liquid leakage detection line
US9192896B2 (en) 2007-06-27 2015-11-24 H R D Corporation System and process for production of liquid product from light gas
WO2020060600A1 (en) * 2018-09-20 2020-03-26 Rosemount Inc. Thermowell with primary seal verification
CN111081609A (en) * 2019-12-26 2020-04-28 西安奕斯伟硅片技术有限公司 Cleaning and etching system
CN112824741A (en) * 2019-11-21 2021-05-21 新疆金风科技股份有限公司 Liquid leakage checking system and liquid leakage checking method
CN113577356A (en) * 2021-08-17 2021-11-02 河南华福包装科技有限公司 Packaging carton forming equipment
US11788918B2 (en) 2020-06-18 2023-10-17 Trevillyan Labs, Llc Fluid detection fabric

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2552508A1 (en) * 1975-11-22 1977-05-26 Kunststoffabrik Erich Dittrich Flexible plastics air induction pipe - has optically transparent cover to form hollow chamber filled with alcohol based damage indicating liq.
DE2854016A1 (en) * 1978-12-14 1980-07-03 Ropertz Safety pressure hose construction - has transparent outer sleeve enclosing substance which changes colour in presence of leak
US4244693A (en) * 1977-02-28 1981-01-13 The United States Of America As Represented By The United States Department Of Energy Method and composition for testing for the presence of an alkali metal

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2552508A1 (en) * 1975-11-22 1977-05-26 Kunststoffabrik Erich Dittrich Flexible plastics air induction pipe - has optically transparent cover to form hollow chamber filled with alcohol based damage indicating liq.
US4244693A (en) * 1977-02-28 1981-01-13 The United States Of America As Represented By The United States Department Of Energy Method and composition for testing for the presence of an alkali metal
DE2854016A1 (en) * 1978-12-14 1980-07-03 Ropertz Safety pressure hose construction - has transparent outer sleeve enclosing substance which changes colour in presence of leak

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2307558A (en) * 1995-11-23 1997-05-28 Bosch Gmbh Robert Device for indicating leakage in hollow bodies which convey fluids
EP0859078A1 (en) * 1997-02-13 1998-08-19 Electrolux Zanussi S.p.A. Conduit for conveying a flow of fluid under pressure
NL1012596C2 (en) * 1999-05-12 2000-11-14 Pipelife Nederland Bv Protected plastic pipe for conveying liquid and/or gas, comprises liquid and/or gas tight inner plastic layer provided with outer plastic layer which is deformable plastically under influence of local load
DE10044039A1 (en) * 2000-09-07 2002-03-21 Brugg Rohrsysteme Gmbh Flexible pipeline comprises two concentric pipes with fleece layer in interspace between same and made of material to swell up when moisture enters
WO2003069298A1 (en) * 2002-02-12 2003-08-21 HÖRLIN, Emil, Oskar Device and method for detection/indication of liquid leakage
US7213534B2 (en) 2002-02-12 2007-05-08 Tom Invent Ab Device and method for detection/indication of liquid leakage
WO2005019816A1 (en) * 2003-08-20 2005-03-03 Honeywell International, Inc. Leak detection method using microencapsulated dye precursor
GB2410561A (en) * 2004-01-27 2005-08-03 David John Roughley Water leak detector
GB2410561B (en) * 2004-01-27 2007-08-01 David John Roughley Water leak detector
US8497309B2 (en) 2007-06-27 2013-07-30 H R D Corporation Gasification of carbonaceous materials and gas to liquid processes
US9192896B2 (en) 2007-06-27 2015-11-24 H R D Corporation System and process for production of liquid product from light gas
US9592484B2 (en) 2007-06-27 2017-03-14 Hrd Corporation Gasification of carbonaceous materials and gas to liquid processes
DE102011075998B3 (en) * 2011-05-17 2012-11-15 Simona Ag Container, tube or chemical apparatus with color indicator and composite semi-finished product with color indicator for the production of a container, tube or chemical apparatus
CN103454047A (en) * 2012-05-28 2013-12-18 大自达电线株式会社 Liquid leakage detection line
WO2020060600A1 (en) * 2018-09-20 2020-03-26 Rosemount Inc. Thermowell with primary seal verification
US11002628B2 (en) 2018-09-20 2021-05-11 Rosemount Inc. Thermowell with primary seal verification
CN112824741A (en) * 2019-11-21 2021-05-21 新疆金风科技股份有限公司 Liquid leakage checking system and liquid leakage checking method
CN111081609A (en) * 2019-12-26 2020-04-28 西安奕斯伟硅片技术有限公司 Cleaning and etching system
US11788918B2 (en) 2020-06-18 2023-10-17 Trevillyan Labs, Llc Fluid detection fabric
CN113577356A (en) * 2021-08-17 2021-11-02 河南华福包装科技有限公司 Packaging carton forming equipment
CN113577356B (en) * 2021-08-17 2023-04-25 河南华福包装科技有限公司 Packaging paper box forming equipment and killing and leakage detecting method

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