IL31345A - Process of sealing,detecting and/or locating leaks - Google Patents

Description

PROCESS OF SEALING.DETECTING AND/OR LOCATING LEAKS m¾>» 3 ninss ικ/ι *I¾>»A ,na»eu¾» i*?n This invention relates to a process of sealing leaks in a vessel and the like adapted for containing a fluid therein which includes the steps of filling said vessel with a gaseous or volatilized sealant agent admixed with a vehicle ga3 inert thereto, applying pressure on the interior of said vessel sufficient to permit escape of said sealant agent from a leak present in said vessel into the ambient enviroment at prevailing temperature conditions and for a period of time sufficient to react with oxygen or moisture present in said enviroment to form a solid seal in the situs of the leak.

In addition, the invention relates to a process for detecting and/or locating the leaks in the vessel conduit and the like by employing a sealant which acts an an indicant or which is admixed with an indicant agent, which includes the steps of filling said vessel with a gas, other that a fuel gas, containing said sealant or said sealant admixed with an indicant agent, said sealant or indicant being present in said gas in an amount sufficient to be observable when said gas containing the sealant or indicant escapes from said vessel, and observing the escape of said sealant or indicant agent at the locus of said vessel where a leak is present.

Where the gas includes fuel gas, the invention may include the steps of purging said vessel with an inert gas, sealing said vessel after filling it with said gas containing an indicant agent, maintaining a predetermined super-atmospheric pressure in the interior of said vessel and thereafter observing the escape of said indicant agent with a sealant or a sealant and an indicant agent, said indicant agent being disphosphine; a monoalkylphosphine having the structure RPH2 wherein R is an alkyl having 1 to 4 carbon atoms; dimethylphosphine; methylethylphosphine; trifluoromethylphosphine having the structure (CF3)nPH3_n, wherin n is 1 or 2; mixtures thereof; phosphine and a pyro- phoric compound; a silane having 1 to 4 silicon atoms; disiloxane; trisilylamine; or trisilylphosphine arid the alkoxy boron compound sealant being an alkexide-bor-ane- having the formula: *ήΒ <0R'>3-n wherein R is an aliphatic straight chain, branched chain or. cyclic organic group having 1 to 10 carbon atoms, R' is an alkyl group having 1 to 3 carbon atoms, and n is an 2 integer 0 to $; said sealant or indicant upon leakage re- acting with oxygen or moisture present to produce from its container an observable signal.

The sealant of the present invention is also useful in pre-testing vessels, pipe systems and the like for visually locating any existing leaks therein. Such vessels or;>pipe systems are filled with an inert non-oxi¬ dizing gas admixed with a suitable sealant which also acts as a visual indicant, or mixtures of such sealants and other indicant agents, and when suitable pressure is applied to the closed vessel or > ipe system the escape of the admixed gas and indicant into the atmosphere can be visually detected at the point where any leaks, cracks or fissures exit.

Some of the utilizations of this invention are a - indicating the leak. It further can be used in aircraft pipe^ systems, hydraulic or gas systems. It can be utilized in pipelines for a pre-test prior to operation. It further can be used by plumbers that are "hooking up" a house or industrial system. It can also be used by building inspectors to check the tightness of systems within homes, industrial plants,, etc. Another application of this invention is the ;riodic ' .. . · ' red c testing of piping systems such as telephone conduits, and the like. One of the major problems with buried telephone conduits is that shouldithe existing gas that is put in the conduit escape undetected it would lose its anti-corrosive properties as well as its anti-electric magnetic interference.

My process makes it possible for a quick, economical pre- periodic testing of systems and -pevodic testing.

The article "Detection, Repair, and Prevention of Gas Leaks" published in American Gas Journal, August 1959, pages 16-28, points out that fuel gas lost through leakage represents a great economic loss today besides potential hazard to public safety. This article contains a survey of ten company practices and refers to 100 literature references. The article refers to the various methods used to detect gas leaks.

The detection and location ofgas leakage has been previously based on a variety of physical and chemical principles which are costly, require elaborate and expensive equipment and trained technical personnel. The most widely used means is a combustible gas indicator which is based on ""-> The heat of combustion increases the electrical resistance ^ of the wire which is used as a basis for determining the amount of combustible gas present in the sample atmosphere.

Stethoscopes, sonic leak detectors, mass spectrometers and even trained dogs have been used to detect leaks in fuel gas mains. The addition of strong odoriferous compounds to gas mains has also been utilized so that leaks might be detected by smell. Radioactive gases have also been added to gases to serve as leak detectors requiring special detection instruments and trained personnel.

Also the use of visual indicants to pre-test leaks in closed systems or vessels offers many advantages over prior methods such as hydrostatic tests, soap test, helium mass spectrometer, etc. Newly laid distribution mains are commonly pressured with gas to test them for tightness prior to being placed in service. Leakage is often detected by the decline in the pressure in the mains as indicated by a recording pressure gage; the dragnet leak detector was developed to facilitate this type of leakage test.

The testing of pipelines is frequently a difficut. and expensive; task. For economic and safety reasons, pipelines must be leak-free. Hence, each pipeline must be tested for leaks at, or above, its expected operating pressure. In some situations, as in heavily populated areas or where it is required by local regulations, pipelines must be hydrostatic-ally tested.

When a line is hydrostatically tested the presdnce If a line under test is in an open ditch, leaking water can be easily seen in the bottom of the ditch. Many existing buried lines are tested and leaking water may, or may not, show at the surface of the ground.

In some formations water leaking out of a pipeline will drain down into the ground and will never show above-ground. In others, drainage may be lateral. In swampy areas, leaking water will just mix with the surrounding waters. From the foregoing, it may be seen that hydrostatic testing has some serious limitations.

Gaseous radioactive tracers have also been used to locate leaks in buried pipelines. Short half-life radioactive tracers have also been used in the conduct of flow efficiency tests on gas transmission piping, but these tracers have not been applied to the detection and location of leaks in gas transmission or distribution piping. The general disadvantage of tracer methods is that controlled injection of the tracer substance is required, an operation that presents many practical difficulties in gas distribution systems.

The oldest and most common method for detecting leaks consists of applying externally a soap solution to the joint or to the point of the apparatus where a leak or crack is believed to be present, and simultaneously introducing a gas into the apparatus under pressure. The appearance of bubbles indicates a leak in the joint or the presence of a crack. The main drawback is that the bubbles have very short life, in the range of a few seconds, and may not be observed It is necessary that each valve and joint be painted with soap or a chemical solution to detect leaks. In most cases, it is difficult to get to "hard to get to places". Further, it is difficult to see leaks in the area away from the observer. Further limitations are that in a number of cases there are leaks in the pipe. Thus, it could only be discovered if the leak itself were pinpointed prior to the soap application.

Another method in detecting leaks in the use of hydrogen and helium that is put in the pipeline under pressure and would necessitate the observer to slowly scan the pipe and all the fittings with sensor equipment. This, too, has many serious limitations because there are many areas and surfaces that the observer or technician cannot get to in order to isolate the leak.

Ind.

Winter et al. in -I-ng-. Eng. Chem. 50 No. 5, page 53A (1958) reviewed the established methods for detecting leaks in the process equipment. The radioactive tracer method described therein is expensive since it involves the use mainly of radioactive phosphorus. The halide torch method utilized a halide torch for detecting a leak, and necessitates the introduction of both Freon and air within the apparatus being tested. Other methods are essentially based on the color change of different indicators.

According to this invention sealant agents are introduced into the interior of the vessel under pressure in gaseous form or in a suitable inert gaseous vehicle, or moisture present at the ambient exterior locus of the vessel^ where the leak exists and forms a solid product in situ which seals the leak. The sealant agents suitable for this invention are selected normally gaseous or volatile metal hydrides, metal alkyls, metal alkyl halides, and metal alkyl hydrides. These sealant agents are mixed with a non-reactive vehicle gas, such as hydrogen, helium or nitrogen in amount so that upon escape of the admixed gas from a leak into the atmosphere a seal will be produced. These sealant agents are preferably substances which are easily volatilized and which can be admixed with the inert vehicle gas and carried along with the gas in the vessel. If a leak is present, the sealant agent upon escape into the atmosphere reacts with the oxygen and/or moisture in the ambient air to produce a solid seal at the situs of the leak.

Sealant agents for admixing with vehicle gases may be selected silicon hydrides and boron hydrides. The agents may also be compounds having the general formula; M Rn x3-n wherein M is aluminum or boron; R is an aliphatic or ole-finic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms; x is hydrogen or halogen selected from the group of chlorine, bromine, iodine and fluorine; and n is an integer of at least 1. triethyl Specific illustrative sealant agents are tire- hyt aluminum, ethyl aluminum sesquichloride, diethyl aluminum chloride, ethyl aluminum dichloride, diisobutyl aluminum quichloride, diisobutyl aluminum hydride, triisohexyl alu- ^ minum, tri-n-hexyl aluminum, tri-n-octyl aluminum, tri-n- butyl aluminum, tri-n-decyl aluminum, aluminum isoprenyl, tri-n-propyl aluminum, triisopropyl aluminum, tri-n-butyl aluminum and tricyclohexyl aluminum. Boron compounds analogous to the aforementioned aluminum compounds may be used such as boron triethyl, boron diethyl , bromide, etc. alkoxy boron compounds Other suitable sealant agents are alkexide- box-&a&k having the general formulas wherein R is an aliphatic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms, R' is an alkyl group having 1 to 3 carbo atoms, and n is an , 2 integer of 0 to ί. Examples of these sealant agents are B(OCH3)3 (trimethoxide borane) and CH3B(OC2H5)2 (methyl- alkoxy boron compounds diethoxy borane) . These boron- -aik-ox-ides- react with moisture^ to form a solid plug containing boric acid which sdrve to seal any leaks present upon escape into the atmosphere containing moisture.

Other suitable sealant agents may be compounds having the formula: Z Rn X2_n wherein Z is zinc or cadmium? R is an aliphatic straight chain, branched chain or cyclic organic group having 1 to carbon atoms; X is hydrogen or a halogen from the group of chlorine, bromine, iodine and fluorine? and n is an integer of at least 1. butyl cadmium, dioctyl zinc, and dicyclohexyl zinc.

These sealant agents may be added to vehicle gases in concentration ranging from about 0.005 to about 10% by weight in the vehicle gases. They may also be conveniently added in solutions of suitable hydrocarbons , such as butane, hexane, heptane, etc. which will uniformly volatilize or disperse in the vehicle gas. When the admixed gases escape into the atmosphere they produce in situ a solid seal.

The following are illustrative examples in practicing this aspect of the present invention: Two holes 1/32 inch and 1/16 inch were drilled into a three foot length of standard lead telephone conduit. Dry nitrogen was passed through :the conduit for 18 hours to dry the conduiti>prior to starting the flow of the sealant. The room temperature ranged from 68° to 76°P. and the relative humidity was 48% to 54% during the run. Diethyl zinc in approximately a concentration of 500 ppm was then supplied in the nitrogen stream. It was found that lower pressures and slower flow rates were required for sealing the holes. All holes sealed themselves, but varied in the time required. The 1/32 inch hole sealed in 2¾ hours, at a pressure of 3/4 to 1 pound.

It took approximately 3¾ hours to seal the 1/16 inch hole at ½ pound pressure. Increasing pressure to 1 pound opened the hole again. It was found that, ¾:f after the leak had been sealed and the pressure was not increased the pressure. This time a leak did not develop until 11 pounds pressure was reached. It was found that if after 'the hole is sealed, the pressure is not increased until many hours have elapsed, there is a hardening of the zinc oxide complex which is deposited in the situs of the hole that will withstand higher pressures.

Other sealant agents which may be used in like ethyl manner are triethyl aluminum, triethyl borane, eithyi- aluminum sesquichloride. A mixture of 85% triethyl borane and 15% diethyl zinc is suitable for admixture with helium, hydrogen or nitrogen gas in amounts 0.05 to 25%. A hydrocarbon solution containing 25% by weight triethyl aluminum containing a trace of diethyl zinc may also be added to a vehicle gas and volatilized therein.

It will be apparent that the concentration of the sealant agent used and the pressure of the vehicle gas used may be varied over a wide range depending upon the size of the holes which are to be sealed. The time of flow of the sealant composition can lalso be greatly varied in order to seal existing leaks. The metal component of the sealant agent forms solid metal oxide and metal alkoxides complexes when it escapes from the leak into the ambient atmosphere by reacting with oxygen and/or moisture to form solids in situ which in time harden and seal the leak.

The present invention is also suitable for sealing leaks in joints of fuel gas pipelines which comprise bell and spigot joints. Such joints are packed with caulked · Fuel gas lines buried underground in cities are ^ also subjected to earth heaving and vibration caused by vehicles and trucks of the street traffic which produce leaks at the joints. The repair of such leaks is very costly because suctions of the gas main must be exposed by excavating the superposed soil to gain access to the leaking joints for resealing them. According to the present invention excavations are entirely eliminated. The sealant agent is simply fed in a suitable gas vehicle through the pipeline for a sufficient time until the leak is sealed.

Inasmuch as the sealant agents which are used in the present invention react with oxygen and/or moisture in the air when they initially escape from any existing leaks in a vessel they produce a visible smoke which serves to locate the situs of the leak if desired, if the visible smoke is not sufficiently detectable ah indicant agent may be added to the admixed gas and sealant to produce a better visual indication that a leak is present.

After a lapse of time the leak is sealed as previously explained, but if the seal is broken again it will be automatically resealed if the sealing indicant is present in the interior of the vessel. In the case of systems and pipelines which convey a stream of fluid a selected sealant may be supplied to the stream at all times in suitable concentrations so that any leaks which may develop will be automatical^ sealed when the sealing indicant escapes.

When vessels0 pipe systems and the like are prei ti n helium or carbon dioxide and a selected non-reactive sealant agent or a mixture of sealants and indicants is then added in pre-determined amount through a suitably ponnected inlet. When such admixed gas is pumped into a pipe system or container Under various selected pressure any leaks .which may develop are readily and immediately detected visually by the escaping test gas containing a sealant or indicant without requiring any special equipment. In order to colorv" any given gas or mixture of gases, I preferably add a selected indicant agent which may be an inorganic or organic agent and which is stable and non-reactive with the vehicle gas. The indicant is admixed with the gas in the interior of the vessel so that the indicant is uniformly distributed therein and the vessel is then sealed. A predetermined superatmospheric pressure is then maintained in the interior of the vessel and the escape into the atmosphere ■ of the indicant at the locus where a leak may exist can be observed visually. A sufficient amount of the indicant agent is added so that the test gas will be visible to the eye upon escape into the atmosphere. Pressures which are applied to the interior of the vessels and the like to be pre-tested for leaks may vary £rom slightly above atmospheric pressure to several hundred atmospheres depending upon the character of the vessels being pre-tested, the work ing pressures under which they may be normally operated, and the character of the leaks to be detected. In the case of relatively large leaks only moderate pressures are in order, to locate them. The pre-testing pressures may also be maintained at a predetermined level for a suitable period of time or may be pregressively increased to specific levels.

Also, the present invention provides novel indicants for the above described pre-testing as well as for detecting gas leaks in gas lines and containers. The indicants are selected from one of the following pyrophoric indicant agents or mixtures thereof: diphosphine; mono-alkylphosphines having the structure RPH2 wherein R is an alkyl group having 1 to 4 carbon atoms, for example mono-methylphosphine, monoethylphosphine, etc; dimethylphosphine ; methylethylphosphine; monofcrifluoromethylphosphine (CP3) PH2 and diitrifluoromethyl)phosphine (CF3)2PH.

Pyrophoric triggering agents may be added in small amounts to the indicants, if necessary, such as metal alkyls metal alkyl halides, metal hydrides and metal alkyl hydrides Specific illustrative examples of such pyrophoric triggering agents are triethyl aluminum, triethylborane, diethyl zinc, ethyl aluminum sesquichloride, silicon and boron hydrides and aluminum diethyl hydride.

Some of the colorants used for the pre-testing are for a nitrogen vehicle gas, for example, diazomethane, which is^'yellow gas, under normal conditions in an amount from 10 to 20% by volume to give a distinctive color upon escape into the atmosphere. Other colored gases which may be used in suitable amounts are chlorine monoxide, a yellow- gen dioxide or tetroxide, a reddish-brown gas. To vehicle gases, that is, to carrier gases may also be added elemental which is a greenish gas, or elemental bromine, which is a- brownish-red gas, in order to impart color to the gas. These indicant agents must of course be used in compatible environmental conditions which one skilled in the art can readily determine so that the added colored gases will not corrode or react with the equipment receptacle or conduit being tested for leaks. The vehicle gas should of course also be non-reactive with the added chlorine or bromine. A suitable reactive agent may also be added to a selected vehicle gas which is to be colored, so that the added agent will react with all or a portion of' the gas so as to color the gas .

An indicant agent, such as titanium tetrachloride or stannic chloride, whicft will produce a visible smoke upon escape into the atmosphere, may be also added to vehicle gases in accordance with this invention. Also pyrophoric substances may be used which will spontaneously react with oxygen in air and produce a visible smoke when they escape into the atmosphere, such as, for example, dimethyl arsine, boron hydride, and phosphine.

Vapors of phosphorus which upon escape into the atmosphere may phosphoresce in the dark, may also be used as an indicant agent. Also, napthalene or metallic mercury vapors may be added to various gases so that they will fluorence under ultraviolet light. hydrides, metal alkyls, metal alkyl halides, and metal alkyl hydrides. These agents are added to a non-reactive vehicle gas, such as hydrogen, helium or nitrogen in amount so that upon escape of the admixed test gas into the normal atmosphere a visible signal or smoke will be produced. These added indicants are preferably substances which are easily volatilized and which can be admixed with the vehicle gas and carried along with the gas in the equipment being tested. If a leak develops the added agent upon escape into the atmosphere reacts-with the oxygen and/or moisture in the air to produce a visible smoke.

Agents suitable for admixing with vehicle gases used in the pre-testing may be selected silicon hydrides and boron hydrides. The agents may also be compounds having the general formula: M Rn X3_n Wherein M is aluminum or boron; R is an aliphatic or olefinic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms; X is hydrogen or a halogen selected from the group of chlorine, bromine, iodine and fluorine; and n is an integer of at least 1.

Specific illustrative agents are aluminum alkyle such as triethyl aluminum, ethyl aluminum sesquichloride, diethyl aluminum chloride, ethyl aluminum dichloride, di-isobutyl aluminum chloride, monoisobutyl aluminum dichloride, triisobutyl aluminum, aluminum diethyl hydride, methyl aluminum, sesquichloride, diisobutyl aluminum hydride, triisohexyl ■ ■ L tri-n-propyl aluminum, . triisopropyl aluminum, tri-n-butyl aluminum/ and tricyclohexyl aluminum. Boron compounds analogous to the aforementioned aluminum compounds may be used such as boron triethyl, boron diethyl bromide, etc.

' Other suitable agents may be compounds having the formula : Z Rn X2_n wherein Z is zinc or cadmium; R is an aliphatic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms; X is hydrogen or a halogen from the group of chlorine, bromine, iodine and fluorine; and n is an integer of at least 1. > Illustrative specific compounds are zinc alkyls such as diethyl zinc, di-n-butyl zinc, diethyl cadmium, diisobutyl cadmium,, dioctyl zinc, and dicyclohexyl zinc.

These agents may be added to vehicle gases in pre-testing in concentrations ranging from about, 0.005 to about 10% by weight in the gases. They may also be con-venientyl added in solutions of suitable hydrocarbons, such as butane, hexane, heptane, etc. which will uniformly volatilize or disperse in the vehicle gas. When the admixed gases escape into the atmosphere they produce a visible smoke.

Also according to the present invention, certain indicants which provide heat reactions hereinafter referred to as heat-indicants are most advantageously used in the. field for example with fuel gases. When the admixed test or surroundings to develop heat which can be observed by infrared detectors. A mixture of 85% triethyl borane and 15% diethyl zinc has been found suitable for admixture with helium, hydrogen or nitrogen gas in amounts 0.05 to 25%. A hydrocarbon solution containing 25% by weight triethyl alu-πάήμιη containing a trace of diethyl zinc may also be added to a vehicle gas and volatilized therein for detecting leaks.

When an indicant is used which is pyrophoric in the normal atmosphere it is necessary to use a non-reactive or inert vehicle gas. In such cases the air or other fluid present in the vessel to be pre-tested is first completely purged or flushed out with an inert gas, such as nitrogen, hydrogen, helium or carbon dioxide and a selected non-reactive indicant or mixture of indicants is then added in predetermined amount through a suitably connected inlet. The indicant is admixed with the gas in the interior of the vessel so that the indicant is uniformly distributed therein and the vessel is then sealed. A predetermined superatmospheric pressure is then maintained, in the interior of the vessel and the, escape into the atmosphere of the indicant at . the locus .where a leak may exist can be observed visually. < When using an indicant which is not reactive with air, ,the indicant can be simply, introduced into the sealed : interior of the vessel and the like, in suitable amount. .... · ■>.; The previously described indicant .agents are admixed with non-oxidizing vehicle gases for pre-testing leaks in vessels and the like with the novel indicants also being of gas. Other novel indicant agents sych as silanes having 1 to 6 silicon atoms, disiloxane, trisilylamine, trisilyl-phosphine are suitable. Mixtures of a silane and phosphihe are also suitable as indicant agents ., The indicant agents are used .in sufficient amount so that upon, escape, into the atmosphere they will react with the oxygen in the atmosphere and produce, a visible smoke, or signal. . In case the vessels and the like or gas lines, should contain small amounts of oxygen, the selected indicant agent may react with the oxygen present and thus serve as an oxygen scavenger. Also where pipelines are buried in soil which may contain significant amounts of moisture sufficient indicant is used in the pipe lines so that upon leakage through the soil a visible smoke is produced, although some of the indicant may. react with the moisture present in the soil. When a substantial leakage occurs the escaping gas tends to produce fissures in the soil which . tend to dry and harden due to the evaporative effect of the, escaping gas, so that the gas containing the indicant will escape into the atmosphere and produce a visible signal.

It is apparent that other specific sealamt agents or indicant agents having the properties previously described ma be readily selected in . the light of the teaching of. this invention for admixing with the vehicle gases.

The expression "vessel and the like" used in the appended claims is intended to include pipes, conduits,· containers, tanks, vessels, and closed systems having spaces

Claims (27)

31345/3

1. The process of sealing leaks in a vessel and the like adapted for containing a fluid therein which includes the steps of filling said vessel with a gaseous or volatilized sealant agent admixed with a vehicle gas inert thereto, applying pressure on the interior of said vessel sufficient to permit escape of said sealant agent from a leak present in said vessel into the ambient environment at prevailing temperature conditions and for a period of time sufficient to react with oxygen or moisture present in said environment to form a solid seal in the situs of the leak.

2. The process of claim 1, wherein the interior of said vessel is purged with an inert gas prior to the introduction of the sealant agent.

3. The process of claim 1 or 2, for additionally detecting and/or locating the leaks in the vessel conduit which includes the steps of filling said vessel with a gas containing said sealant agent, said sealant being present in said gas in an amount sufficient to be observable when said gas containing the sealant escapes from said vessel, and observing the reaction product produced upon the escape of said sealant agent at the locus of said vessel where a leak is present.

4. The process of claim 1, 2 or 3, for additionally detecting and/or locating the leaks in the vessel conduit and the like by employing a gas containing said sealant and an indicant agent, which includes the steps of filling said vessel with a gas, other than a fuel gas, containing said sealant and said indicant agent, said indicant agent being present 31345/3 gas containing the indicant escapes from said vessel, and observing the escape of said indicant agent at the locus of said vessel where a leak is present.

5. The process of claim 1, 2, 3 or 4 wherein the gas includes fuel gases, including the steps of purging said vessel with an inert gas, sealing said vessel after filling it with said gas containing said sealant or said sealant and an indicant agent, maintaining a predetermined super-atmos¬ pheric pressure in the interior of said vessel and thereafter observing the escape of said indicant agent or the reaction product produced upon the escape of said sealant at the locus of said vessel where a leak is present.

6. The process of any of claims 1 through 5, wherein the saalant agent is an alkoxide borane having the formula : RnB <0R'>3-n wherein R is an aliphatic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms, R' is an alkyl group having 1 to 3 carbon atoms, and n is an integer 2 0 to i.

7. The process of any of claims 1 through 6, where¬ in the sealant agent is a normally gaseous or volatile com¬ pound selected from silicon hydrides and boron hydrides; a compound having the formula: M Rn *3.n wherein M is aluminum or boron; R is an aliphatic or olefinic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms; X is hydrogen or halogen selected from 31345/3 t is an integer of at least 1; and a compound haying the formula: z Rnx2-n wherein Z is zinc or cadmium; R is an aliphatic straight chain; branched chain or' cyclic organic grouping having 1 to 10 carbon atoms; X is hydrogen or "a halogen from the group of chlorine, bromine; iodine, and' fluorine;' and n is an integer of at least 1.

8. The process of any of the preceding claims wherein the sealant agent is an aluminum alkyl.

9. The process of any of claims 1 through 7, wherein the sealant is a zinc alkyl.

10. The process of any of claims 1 through 7, wherein the sealant agent is diethyl zinc.

11. The process of any of claims 1 through 7, wherein the sealant agent is triethyl aluminum.

12. The process of any of claims 1 through 7, wherein the sealant agent is a mixture of triethyl aluminum and diethyl zinc.

13. The process of any of claims 1 through 7, wherein the sealant agent is trimethoxide borane.

14. The process of any^ of claims 1 through 7, wherein the sealant agent is triethyl borane, diethyl zinc or ethyl aluminum sesquichloride.

15. The process of claim 4 or 5, wherein the diazo indicant agent is di¾xomethane, chlorine monoxide, chlorine dioxide, n trioxide, nitrogen trioxide, nitrosyl bromide, nitrosyl chloride, nitry.l chloride, nitrogen dioxide, 3134S/3

16. The process of claim 4 or 5, wherein the indicant agent is a pyrophoric gas.

17. The process of claim 16, wherein the pyrophoric arsine gas is dimethyl araine-, phosphine or boron hydride.

18. The process of claim 4 or 5, wherein the indicant agent is a fluorescent agent.

19. The process of claim 4 or 5, wherein the gas diphosphine includes fuel gases, and said indicant agent is ei-e-phoeph-tHe ; a monoalkylphosphine having the structure RPH2 wherein R is an alkyl having 1 to 4 carbon atoms; dimethyl phosphine; methylethylphosphine 7 or trifluoromethylphosphine having the structure (CP3)nPH3 wherein n is 1 or 2 ; or mixtures thereof.

20. The process of any of the preceding claims including the step of admixing the sealant agent or the sealant agent and the indicant agent with said gas until the indicant agent is uniformly distributed therein, prior to filling the vessel with gas.

21. The process of any of the preceding claims including the step of flushing out all the air present in the interior of said vessel with a gas containing said seal¬ ant agent and/or said indicant agent prior to filling the vessel with the gas.

22. The process of any of the preceding claims, in which the sealant agent or the indicant agent is a heat- indicant whose escape _is observed by infrared detection equipment.--

23. A gas admixed with a sealant agent and when 7, 31345/3 being an alkoxide borane having the formula: wherein R is an aliphatic straight chain, branched chain or cyclic organic group having 1 to 10 carbon atoms, R is an alkyl group having 1 to 3 carbon atoms, and n is an 2 integer 0 to i, said sealant agent being present in sufficient quantity that upon leakage from its container it will react with oxygen or moisture present to produce an observable signal.

24. A gas admixed with an indicant agent, and when used in the process of claim 4 or 5, said indicant diphosphine agent being ■di-sphos-phine7 a monoalkylphosphine having the structure RPH2 wherein R is an alkyl having 1 to 4 carbon atoms ; dimethylphosphine; methylethylphosphine ; trifluoromethyl-phosphine having the structure (CF3)nPH3_ni wherein n is 1 or 2; mixtures thereof; phosphine and pyrophoric compound; a silane having 1 to 4 silicon atoms; disiloxane; trisilyl- trisilyl . amine; or 4¾*i-3-i-lylephosphine, said indicant agent being present in sufficient quantity that upon leakage from its container it will react with oxygen or moisture present to produce an observable signal.

25. The process of detecting and/or locating leaks in a vessel and the like substantially as described herein with particular reference to any of the specific examples.

26. A gas admixed with a sealant agent substantially as described herein with particular reference to any of the specific examples.

27. A gas admixed with an indicant agent sub