pepe63xnotuse Posted April 2, 2015 Share Posted April 2, 2015 That's an interesting link Derek... It certainly shows how involved and time consuming, the checking over/refurb'ing and turning around of a cylinder can be... Link to comment Share on other sites More sharing options...
StuartO Posted April 2, 2015 Author Share Posted April 2, 2015 The article Derek links to describes Calor's cyliner refurbishment process, which doesn't seem to include internal inspection, concentrating instead on external corrosion. They do a hydraulic test using kerosene, looking for leaks of kersosene as an indicator of a fault. Cylinders are retempered (by heating to 650 deg C in an oven) to ensure that any metal repairs (mostly dent removal) are fully restored in strength. Extrenal corrosion other than very superficial stuff causes a cylinder to be scrapped. The implication is perhaps that we should look for surface corrosion of the pressure vessel on our re-fillable cylinders, even if we don't pressure test them. The other implication I draw is that in order to pressure test it is necessary to remove the valves and after testing new ones are usually fitted. Since re-fillables have two or four holes and the valves and fittings (more elaborate that for a Calor cylinder) will cost money, if you have a corroded or damaged cylinder it will probably be best to replace it with a new one. Link to comment Share on other sites More sharing options...
PeteH Posted April 2, 2015 Share Posted April 2, 2015 Hi. Visual inspection of the interior of a Cylinder with a single hole, is unsatisfactory, requiring at best an endoscope with the facility to turn 90 degrees back upon itself. In the "Good Old Days" we where issued with a Torch with a long probe and a Mirror which clipped to the end! The result of such an examination can still normally require the additional use of NDT testing. Visual examination only allows you to assess the level of Pitting or Corrosive Deterioration, the condition of the welded seams, is more usefully assessed by Hydraulic testing. Therefore Calor, and I assume the bulk of the "industry" too, tend to eschew visual examination and opt to Hydro test, as being more effective. Especially in their case where it is pretty much an Industrialised system.? At one time testing was carried out using Nitrogen and immersing in a water tank!!. Not an entirely "safe" method and was dropped after several "Near misses"!!!! Pete Link to comment Share on other sites More sharing options...
DJP Posted November 6, 2017 Share Posted November 6, 2017 Just an update on this 2 year old thread, nothing has changed! More and more of us will now be getting to the stage where our bottles are approaching 10 years of age. I have spent a considerable number of hours on the phone, online, emails and cannot find anyone who will pressure test my 10 year old MTH gas bottles. Well, to be exact, I did find one company in Birmingham. He wanted the bottles sent to him by courier, a problem in itself. The return process would take a week and the cost, although not quoted other than, 'our companies charges would be similar to you replacing your cylinders with new ones. So, we have order new bottles and new filler and pipes, as they are also 10 years old obviously. My old aluminium ones are worth £50 scrap value. what I did discover was the the propane gas we use can cause a chemical reaction with the aluminium bottle and corrosion will be apparent from the inside, so an examination from the outside may not reveal any issues. Its also very poor that none of the well known aftermarket suppliers of refillable bottles can offer a pressure testing service and cannot offer any guidance where to have their products tested. All very good for company sales when your only choice is to replace all the set up with new kit if you want to retain the refillable bottle. Calor gas do pressure test for obvious reasons, but only on their own bottles, other suppliers told the same story. Link to comment Share on other sites More sharing options...
StuartO Posted November 7, 2017 Author Share Posted November 7, 2017 I understand that the cut off was extended from ten to fifteen years, at which point it does seem to be expedient to replace the bottles with new ones. At least they are cheaper than they used to be! Link to comment Share on other sites More sharing options...
Will86 Posted November 7, 2017 Share Posted November 7, 2017 But how do you know if your NEW bottle is a new one ? Presumably there is no date stamp or code which would require records to be kept 'at a cost'. Attachment fittings could be changed which means nothing. Second-hand bottles are widely advertised. Link to comment Share on other sites More sharing options...
StuartO Posted November 7, 2017 Author Share Posted November 7, 2017 All pressure vessels have the date of testing stamped on to them, usually on or near the neck. Link to comment Share on other sites More sharing options...
Will86 Posted November 7, 2017 Share Posted November 7, 2017 Thank you. Link to comment Share on other sites More sharing options...
monique.hubrechtsgm Posted November 9, 2017 Share Posted November 9, 2017 Just simple follow the rules set out for these bottles. Burst tests are only done in final approval of their design. according pressure vessel rules Now europe, before per country and you back to before. A leak test on gas is 10 percent above max working pressure . In any case bottles and underslung tanks can not be tested IN-SITU if lower pressure classes are connected to them. Link to comment Share on other sites More sharing options...
monique.hubrechtsgm Posted November 9, 2017 Share Posted November 9, 2017 The follwing tests are done on a pressure vessel, even your small camping gas bottle. First a burst test in design stage whit water. In series production 1.5 times design pressure whit certificate. When on gas a leak test 10 percent above the maximum working pressure. See your certificate provided whit the equipment, which you have to show in germany on demand for your equipment, but not for bottles. The data is on the bottle itself. In belgium durig the Mot every year a leak test is carried out and the outside of it. Link to comment Share on other sites More sharing options...
flicka Posted November 9, 2017 Share Posted November 9, 2017 This thread got my grey cells pondering. Motorhomes with refillable lpg tanks or cylinders must only represent a small proportion of vehicles with such. With all the Chelsea tractors, black cabs & landrovers fitted with lpg tanks one would assume there are checks under the MOT requirements ?? Will ALL these adhere to regulations? Should Motorhomes with refillable log tanks also be subject to checks at MOT? So we have potentially many mobile bombs in circulation, especially in the capital. FFT. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted November 9, 2017 Share Posted November 9, 2017 flicka - 2017-11-09 5:39 PM ...With all the Chelsea tractors, black cabs & landrovers fitted with lpg tanks one would assume there are checks under the MOT requirements ??... There’s a sub-section (7.3.7) in the MOT Test Inspection Manual that deals with testing of ‘multi-fuel vehicles’ and advises that "Multi fuel vehicles Vehicles which run on more than one fuel(e.g. petrol and LPG) should be tested on the fuel they are running on when presented.” https://www.mot-testing.service.gov.uk/documents/manuals/m4s07000304.htm Although the majority of motorhomes will carry LPG in bottles or a tank, that gas will not fuel the vehicle and, consequently, MOT sub-section 7.3.7 will not be relevant to those bottles/tank. When the LPG does fuel the motorhome (eg. on petrol-engined USA RVs that have had an LPG conversion) and the motorhome is running on LPG when presented for MOT testing, sub-section 7.3.7 will apply. Link to comment Share on other sites More sharing options...
Keithl Posted November 9, 2017 Share Posted November 9, 2017 Derek Uzzell - 2017-11-09 6:23 PM flicka - 2017-11-09 5:39 PM ...With all the Chelsea tractors, black cabs & landrovers fitted with lpg tanks one would assume there are checks under the MOT requirements ??... There’s a sub-section (7.3.7) in the MOT Test Inspection Manual that deals with testing of ‘multi-fuel vehicles’ and advises that "Multi fuel vehicles Vehicles which run on more than one fuel(e.g. petrol and LPG) should be tested on the fuel they are running on when presented.” https://www.mot-testing.service.gov.uk/documents/manuals/m4s07000304.htm Although the majority of motorhomes will carry LPG in bottles or a tank, that gas will not fuel the vehicle and, consequently, MOT sub-section 7.3.7 will not be relevant to those bottles/tank. When the LPG does fuel the motorhome (eg. on petrol-engined USA RVs that have had an LPG conversion) and the motorhome is running on LPG when presented for MOT testing, sub-section 7.3.7 will apply. Derek, But section 7.3.7 is titled 'EXHAUST EMISSIONS' and does not cover the pressure testing or safety of the components of the 'propulsion system' only the exhaust gas emissions. It is also only applicable to 'Spark ignition' engines, ie not Diesels! Keith. Link to comment Share on other sites More sharing options...
Wilf Posted November 9, 2017 Share Posted November 9, 2017 ITS ALL A CON Just read this http://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Replacing-Gaslow-cylinders/47364/ Link to comment Share on other sites More sharing options...
Derek Uzzell Posted November 10, 2017 Share Posted November 10, 2017 I’ve read it (and posted in that thread) but I still don’t understand what relevance “ITS ALL A CON” has. Link to comment Share on other sites More sharing options...
StuartO Posted November 10, 2017 Author Share Posted November 10, 2017 I suspect that its the very modest 15-20% discount on a new cylinder for your old one which irks; back in the day I owned some compressed air diving cylinders and they had to be tested periodically but I don't recall that it cost anything like 80% of the cost of a new cylinder to test them. In practice of course there is no enforcement of lpg cylinder periodic testing, the Government just relies on the rental companies to incorporate testing into their filling processes and perhaps monitors that because they can do so easily by visiting the refilling factory and checking records. The Government probably haven't caught up with the development of privately owned refillable lpg cylinders - or maybe they think its a low risk scenario! For the motorhome owner who has ageing refillable gas bottles it's just tempting to keep using them until they develop a problem because the chances of officialdom showing any interest is negligible. Link to comment Share on other sites More sharing options...
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