1 10 1 https://d1y502jg6fpugt.cloudfront.net/21127/archive/files/734e40c3101cfc0d6c4d2b9b12fd9b38.pdf?Expires=1776902400&Signature=cVw159Qwi2kzHeRLrzER0sbBzeAqns43nz8LOTd6mu%7ECYyNk-164DxXmPiq88jDiLU-89tDonI%7EDL5SLp-PHjwYm7lHRaqMhROnoW-8tf%7E18FOeD2Qy4rALWDg4HiBkGPslTBuWO7W4ptkJ11zaPB6nHvpzzR0hv80bq3kO7T55eXSsGtGNW2jPXC67Bk4aDbPXj2vXJqmK6TchjXCf2BH7S0EBqRtoV8XCH84IafUNtvE2s097MPlcWFcY3yyR1plFPXdv6Dh8VWGlGq-2dOIYDAtWEdC6djyhmrOGcSksQsIkA5yCf0mnOYzwgICKbIEfUXcoKXk%7EaicqT4vv4kQ__&Key-Pair-Id=K6UGZS9ZTDSZM c4766edf3236211f441f76a965712e4f PDF Text Text Corrosion, wear and corrosive wear; the story of lubrication systems in large technology object storage and use David Hallam, David Thurrowgood and Col Ogilvie National Museum of Australia My name is David Hallam; I’m currently Senior Conservator Research and Technology at the National Museum. That means that I’m in charge of our research programs and I’m also in charge of our technological conservation program. Before that I was Head of Conservation at Queensland Museum, and before that I spent 20 odd years at the Australian War Memorial and I love functional objects. I also like Volvos. Now, recently, believe it or not, I bought an early Volvo. It was a 1974 Volvo, had very little mileage on it. It had only done 180,000 kilometers since 1974. It had been well maintained. It lived at Grafton. Now for those of you who are not from Australia, Grafton’s a nice humid place. It sat for long periods between short journeys. The owner would take it out, take it for a short drive and park it in the garage again. It was always garaged and when I went to buy it I thought “Ripper - really original car!”. And then I started reading through the documentation that came with it and I went “Oooo - this is going to be interesting”. I got it ready for registration, put it through registration and started using it as my everyday car. Surprise. It failed. All of the oil seals blew. Now, many conservators will tell you that this is an example of how use is damaging. Oh, but it were so simple. I have an even older Volvo. A 36-year-old Volvo. A very, very rare Volvo that has done 288,000 miles (that’s 450,000 kilometers). It’s been used regularly. It was owned by a pushbike-riding fanatic who only used this car when he was going to go on a long trip. So it wasn’t used and then he took it on a long trip. Then he parked it back in the garage again. How many years would it take to do 450,000 kilometers in a museum maintenance program? 7800 years. Now, we’re kidding ourselves if we believe our institutions will last that long. And my car’s still going. Survival of the institutions is more likely to be the rate-limiting step to the preservation of my Volvo (in a museum) than wear. The aim of this paper is to stimulate discussion. I’m not going to give you any answers, I’m going to give you some ideas of what we think are our answers. Most museum preservation practice has not really advanced significantly since the mid 1980s as far as technological object preservation goes. In Australia, most museum practice really came from chemical processing specifications that the National Air and Space Museum in Washington was using, and basically I shifted it across in the mid 1980’s. It hasn’t been modified much since then, but really I don’t think our ideas on conservation have moved that much since then either. Working object practice in institutions is based on standard mechanical engineering workshop practice or migrated military inhibition practice. And again, it’s not really been adapted to museums and long-term use of objects. We’re still �doing things the way we would in a garage, or in steam workshop – again we really have not progressed. Our aim should be to find the rate limiting steps for maximising use and preservation. We believe that our conservation practice should be based on: – an assessment of the relative risks of wear and corrosion in the museum’s storage environment; – an assessment of the risks associated with application of a maintenance program to the collection as a whole; – the risks associated with the use of an individual object. You need an assessment of the risks associated with the application of a maintenance program to the collection as a whole. Now, it took 15 years or so to get the maintenance program for the Australian War Memorial up and running, and congratulations. Why did it fall over before? Because there were too many risks to it and what Alison’s1 done is taken administrative steps to remove those risks. It’s a great step forward. You need to look at the risks associated with the actual object. Standardised plans for treating objects are great just so long as they’re not used as blanket treatments. A race car engine is going to need totally, totally different preservation to my Volvo. The other thing we really need to push is - in cultural institutions we acknowledge Aboriginal objects, we acknowledge how Aboriginal culture should be taken into account when dealing with those objects. When it comes to engineering culture we totally forget about it. It doesn’t exist. We really need to concern ourselves with engineering culture what do the engineers, what do the people who own those objects, the elders of that area, what do they want done with those objects? And this is something I think conservators don’t do very well at all. We ignore the engineers. “Oh, they’re just mechanics.” Engineering is a science, every bit as complex as chemistry. We need to accept it and embrace it and bring it on board. This is why I believe an understanding for conservators of engineering and wear in museums is really important. Mechanical engineers will tell you that the best way to preserve a mechanical system is to keep it operational, operated and maintained and I think they are right. But we can do even better by applying some conservation practice. What are we conserving? • Conservation of Form • Conservation of Function • Conservation of both Function and Form • Rare trades and skills. • Smell, movement and vibration. • Passion, memories and feelings. 1 Alison Wain Manager, Textiles, Technology and Objects Conservation, Australian War Memorial �You’ve got to conserve the lot. Figure 1: Bean car arriving at the National Museum of Australia under it’s own power in 2000. What is the functional life span of the object? This may be three hundred years or only a decade. The key is to recognize the point at which wear and repair becomes desecration of the original. At some point it becomes better to preserve the original and create a replica for use. If you replace or repair enough of an item it is no longer the item you set out to preserve. Figure 2: Diagram of life cycle of machinery. �Figure 2 shows wear on the vertical axis and time along the horizontal axis. Basically, if you have an engine, you’ll get a little bump in the wear line when the engine is first run in, then the wear will stay pretty flat. This is the period of the economic life of the engine. Then, as the thing eventually starts to break down and reaches the end of its economic life, you get a great increase in wear. You’ll get this for the object as a whole and you will get this for the components of the object. What I’m talking about is the preservation and use of the object while it is within its economic life. Figure 3: Rust on the inside of a cylinder in an engine from the National Museum collection. Okay, I said I was going to talk about corrosion, corrosive wear and wear. What’s this funny thing called corrosive wear? Anyone know who Ricardo is? Basically Harry Ricardo2 is an engineer, a very famous one. English engineer, did a lot of experiments on lubrication and fuels. Was really interested in what happened when an engine fired - what happened inside the cylinders - and was trying to work out how wear occurred. He was really, I suppose, in a way one of the first real tribologists, which are people who study wear. He realized that lubricants covered the inside of a cylinder, but 2 Ricardo, Harry R. “The Ricardo Story The autobiography of Sir Harry Ricardo, Pioneer of Engine Research” 2nd ed Society of Automotive Engineers Warrendale, PA 1992 isbn 1-56091-211-1 �he couldn’t work out what actually was happening in there and was trying to develop an engine which you could actually look inside and stop suddenly. And then one day one of his experimental engines blew up and the cylinder flew off and hit the roof and came down and landed and smashed into pieces and he could actually see where the piston had been, and he could see instantaneously a corrosion ring formed. What had happened was the explosion from the fire from the propellant had burnt the oil off and literally caused an instantaneous layer of rust to form on the inside of the engine. Now, this is something that we don’t actually see happen in modern engines. We don’t get corrosive wear in modern engines basically because the fuels we use today are quite different (they’re not nearly as acidic), and because the lubricants that we use have a much higher film strength and literally bond to the metal surface inside the engine. Figure 4: Corrosive gel on Volvo rocker covers after an engine has been run without coming up to temperature. What we do get in modern engines is corrosion, and this is because quite often what we do with an engine is we drive a vehicle into a storage area and switch it off, turn off the fuel and walk away. We’re left with all the acidic residues and the moisture from the firing inside the cylinders, and the oil that’s there is really ineffective as a long term, protective coating. Oils are designed to be lubricants, they are not designed to be a coating and we end up with corrosion. The moisture and oil form literally a mayonnaise. This is what happens when you use a vehicle and you only use it for a very short time. �I’ve talked about wear and how long a vehicle would have to operate in order to wear itself out. A much worse thing that can happen, and happens often inside a museum, is corrosion and it really damages vehicles. It’s probably happening in every museum we know of, it’s avoidable, and I would almost say it’s criminally neglectful. Figures 5 and 6 show our Land Rover. It’s done 3,802 miles since 1958. A thousand of those miles have been done in the museum service. It’s been filled with a standard lubricating oil. The lubricating oil has been changed about every year. Last time it was used, it was used for the royal tour. We were starting a maintenance program on it and we thought “Well, we’ll whack an introscope down and see what’s happened inside it”. It had sat for about two years. Figures 5 and 6: Corrosion inside the National Museum Landrover cylinders You can see there the corrosion. If we had kicked that engine over, what would have happened? The piston would have gone up and scraped the corrosion off. What’s corrosion? An oxide. What are oxides used as? Abrasives. What size are they? Very small - small enough to go through the filter. So what you’ll end up with is this very fine abrasive slurry, that won’t be picked up by the filter, rotating round and round inside the system. And that’s exactly what happened with my Volvo. I ended up with this nice abrasive slurry and it went through and it ripped out all of the oil seals and did a whole lot of damage. In the museum, if we had kick started the Land Rover, the same thing would have happened. Okay, how have we overcome that? We use nothing but inhibited oils, we don’t use any standard lubricating oils in our institution. Why did we come to this conclusion? We’ve come to this because we’ve actually done some product testing. We tested the oils as coatings not as lubricants. We intend over the next year to do a whole lot more product testing of oils as coatings We’re also going to be doing some work on maintenance cycles because we don’t know whether the maintenance cycle for that Land Rover with an inhibited oil in it should be one year, five years or ten years. And that’s going to make a big of a difference to our planning cycles. We’re also trying to work on a concept of what we’re calling Just Noticeable Wear and I’ll talk about that in a little because one of the things we want to make sure is that our �thoughts on automotive preservation are spread wide and to that end we’re currently working on a manual for museums. I talked about research, here’s something that people might be interested in. We’ve actually been doing some oil testing using Electrochemical Impedance Spectroscopy (EIS). Penrite Shelsley Medium POP2 Castrol GTX Older Vehicles 160 BSTK Uncoated steel 500-SNO Figure 7: EIS spectra for various engine oils. From bottom to top this shows: • a piece of uncoated steel with no oil - that’s the resistance it produces, it’s a bit rough, corrodes reasonably easily; • a piece of steel coated in a lubricating oil; • a piece of steel coated in a base lubricant - a lubricant that has no additives in it (the same base that is used to make up the next oil); • a classic vehicle oil, gives a little better corrosion protection; • an inhibited oil formulated specially for us by Penrite - gives good protection; • a Penrite inhibited classic vehicle oil. Now the fascinating thing about this is the difference between the uncoated surface and the protection given by the most protective oil is ten thousand times. So we can say that this particular oil is several thousand times more protective than some of the least protective. That’s quite an amazing amount. So just by using this kind of oil (and it doesn’t have to be this particular brand) - an inhibited oil - we’re getting massive amounts of protection, and this can totally change our maintenance plan. We’ve obviously also done salt spray tests and other kinds of tests on oils as coatings, and we’re going to be continuing this over the next two to three years. �One of the other things we’re trying to develop is a concept which we’ve taken basically from paper conservators. Paper conservators at the Victoria and Albert, when they display something, talk about Just Noticeable Fade and we’re trying to get this concept into functional objects so we can talk about Just Noticeable Wear (JNW). We don’t know yet exactly how it’s going to work, but we want to be able to quantify the wear of objects and actually talk about what lifetimes we can get out of them, so that we actually know the rate of degradation that they’re undergoing. How should we be carrying out any running? • warm start; • run all systems up to full working temperature; • run for a minimum time (30 minutes?) at varying load; • dehumidify systems on closedown. Okay, this is what we use in the museum and what we recommend other people use, and this is how we currently believe people should be running objects in museums. Notice that we’re dead against running anything for a short period of time. We believe that things should be started warm, run for long enough to achieve full working temperature and stopped in a dehumidified environment. And they should be run under a varying load. We’re currently investigating getting a dynamometer for our museum, so we can run them without actually leaving the building. Maintenance is the core to everything. A program of structured maintenance is likely to substantially improve the probability of a mechanical object’s survival, as the deterioration from wear and corrosion during controlled continuous use and maintenance cycles can be substantially less significant than the damage caused by neglect and periodic, interventionist rebuild cycles. We’ve heard people talk about costs of maintenance. We believe that periodic running and maintenance is very cost effective. We estimate that a stable, running, 1930s vehicle, using appropriate inhibitors costs $500 a year to maintain for materials and labour. It’s not really that much money. In principle, most functional objects are best preserved by preserving their ability to function and using that to conserve them. That’s the only way you can get inhibitors inside for instance. This does not mean that they must be constantly functioning, or operate at maximum capacity. Mechanical objects should preferably be preserved in a state capable of operation, regardless of whether that operation happens once a day or once a decade. Acknowledgements • Veteran Vintage and Classic Lubrication • Penrite Oil Company • University of Canberra for the use of its Raman Microscope Facility • Research School of Chemistry, Australian National University �• • • • Department of Aerospace and Mechanical Engineering, Australian Defence Force Academy National Museum of Australia for the generous support of scientific research by its staff. Ian Stewart, Barry Lambert, Bruce MacDonald and others. Openoffice.org. For the presentation software. � https://d1y502jg6fpugt.cloudfront.net/21127/archive/files/346805d8d0a15a0b0ed0da42db3d5138.pdf?Expires=1776902400&Signature=mNLncyUqMx62T5Nk-PPWgf2%7Eq00CpuXR6tk5l5LkuwXAXUoP9kryXcpsqpE6Ii5%7ESfyahj0UArErjBpR2EtBdcVVA1vGAS5ubAjKbplHXfGnaClQILaky8Labj8T%7EeYwCpZ42ps7W5CmYJoEvnH%7E9UlYijhbu8gdHIRgOrSK7PeMzhxJ2wnQwSfFbChqaYiavjhLSTGi57HXn83h9I44LgGlxFpHWSOgwxVtAgVzTOHtkWQWNatATrRXjJm-%7E945iOG8HsyXXaaIRCK8Q9Hb-0WrMylcxPdO2jRZ30AMQXFIaVeZ2ad73-jIgZFIR1zwRBgWacJw%7Ekr5S2nprGa3dA__&Key-Pair-Id=K6UGZS9ZTDSZM dc98b84624dd62a9a344bfa851c06fc9 PDF Text Text Corrosion, wear and corrosive wear; the story of lubrication systems in large technology object storage and use David Hallam, David Thurrowgood and Col Ogilvie - Question and answer session Davina Bonner: I’m just interested in your concept of the economic life of objects. At what point do you find that an object reaches the end of its economic life and what do you do with it then? David Hallam: You mothball it. Davina Bonner: Is that deaccessioning? David Hallam: No, no - the economic life thing actually came from someone who was a conservator at the Henry Ford (I forget his name), in the mid 1980s. He’s now somewhere down in the south, I’ll remember his name. And it was used to describe the useful life of an object in the world. And what I’m saying is that if something is within that economic life then we can maintain it. We can put it into a maintenance cycle and use it’s functionality to preserve it. Once it gets outside that economic life it is worn out and any function will damage it. Davina Bonner: So you’d look to stabilize…. David Hallam: I would look to mothball it. Davina Bonner: Thank you David Hallam: Using military mothballing techniques. Dave Rockell: We actually run our - we don’t actually have a working car fleet as such anymore - but we have 15 years ago mothballed our whole collection. But two particular cars have been silicon brake fluid treated, plus inhibitor oils and have been suspended in the museum’s roof for 11 years. This year we actually got them out of the roof and reversed our processes and within two hours were driving around the car park. Which is what we thought, because everything’s theory up until you actually try to fire one up again. David Hallam: Okay, I personally would not use – ever - silicon fluids because I believe that traditional fluids are more maintainable. And I think that we need to do some more work there, we need to do some electrochemistry on what actually happens with traditional fluids. But I do have concerns; I’m pleased that you can do that, but I do have concerns with the use of silicon brake fluids. Alison Wain: Could you say why? David Hallam: Because if they’re not applied properly you will end up with pitting corrosion and very, very rapidly totally stuff your brake system. And it’s much simpler to stay with what they were designed for and to add corrosion inhibitors. �Nick Langford: To support your …what you were just saying about silicon brake fluids; we’ve had many disasters with silicon brake fluids in a short space of time, in cars which we’ve prepared for either historic racing or just the, sort of, enthusiast type use. We are getting severe corrosion in aluminium cylinders, with the result that you end up with no brakes whatsoever, which is not very good for the conservative attitude of the motorcar when it hits the tree or something. We’ve found that the best thing to use is the conventional brake fluids - the higher temperature brake fluids are much better than the lower temperature brake fluids for use in drum brake vehicles (which are the cars of the thirties). And the best thing to do with brake fluids is to use [the vehicle] and get the brake fluid hot, and then all of the moisture which has been absorbed into the brake fluid is boiled off and you don’t have any problems. If you use conventional brake fluid on a regular basis it lasts for a long time, and if you look at the service instructions on modern cars for instance the modern brake fluids have a shelf life I think of about two years. So if you take your Volvo, or whatever you choose to drive, in to get serviced, you’ll see that they will change the brake fluids on a regular basis. So it should be treated the same as changing the oils. Thank you. David Hallam: I agree with that. Nikki King-Smith: I’ve got two V16 turbo-charged power plants in the object that I’m supposed to be conserving. I think I’m going to be having a bit of trouble firing those up! They’re of recent vintage. Would you consider that keeping the parts moving (to move the lubrication systems) with an ancillary engine or motor of some sort would be a better case scenario than just mothballing? I mean, I just don’t think that I’m going to be able to turn these things on and maintain them. David Hallam: The problem is, in order to mothball them properly, they need to run. So really what should have happened was the last time that they were run (and this never happens), is they should have been mothballed properly, if they weren’t going to run. Nikki King-Smith: What do I do now? David Hallam: I would tend to use lubricating oils and circulate them through. And I think if you can rotate them, as part of a maintenance program, I think that would be useful. You also should consider dehumidification, dropping the RH inside the actual engines themselves. Using a Munter system or something. I mean how big are they? Nikki King-Smith: Locomotive engines. They’re in the submarine. David Hallam: Yeah, I think you need to consider some dehumidification. Alison Wain: If you do mothball something, even mothballing - if we’re talking about preserving something for decades, hundreds of years potentially - you’ve got to renew that mothballing at some stage. So what do you do then, particularly if you can’t fire your object up? David Hallam: You’ve got a bit of a problem. That’s why in a lot of ways I consider mothballing to be second best. Mothballing becomes part of your cyclic restoration �phenomena, which is why a maintenance program where you can actually kick the thing over is far better. Alison Wain: Even if that’s not firing it up? David Hallam: Yeah, even if that’s not firing it up. That would be my preferred, because at least then you can change the oil. John Kemister: Another suggestion, if you can’t fire it up, is maybe you can throw a few cc’s of vapour phase inhibiting oil in the top end. Now you’ve got to watch that, because if you crank it subsequently you can get a hydraulic block. But usually over the years a few cc’s usually trickle down through the ring caps anyway. Put it in the top and spray it around with a little nozzle. David Hallam: One of the things that you’ll find with an oil that has a decent inhibitor package in it, is it has vapour phase inhibitors and surface inhibitors. So I would suggest that it’s best to go with one package rather than mix and match, because you don’t know what’s in there and you really have to be careful with vapour phase inhibitors They’re wonderful, but I think you’ve got to be careful because they attack things like lead, cadmium, and a few other things like that which you may have in your bearings. So you need to find out what’s in there. What the materials are. Gillian Mitchell: David, I’m interested in your idea of the monitoring and the idea of Just Noticeable Wear and wondering - have you got to the point where you’re thinking about how you might actually go there, and what indicators, where you’ll be looking at and how you’ll measure them? David Hallam: No, we’ve just floated the idea at the moment and we’re very interested in any input, but basically we think it’s a useful way of describing things. Colin Ogilvie: The unfortunate thing about Just Noticeable Wear is for 50 years being a mechanic it’s easy, I’ll have a listen to it, and have a smell of it, and have a feel of it, and yeah, it’s buggered or yeah it’s okay mate she’ll be right. It’s easy for me, but how do you get feel, smell, taste, over to people? You can’t. It’s an experience, so we’ve got to measure it. As a mechanic and an engineer, I can measure most parts of a car in one form or another and I can tell you whether it’s good, bad, or indifferent - it’s longevity, they’re reasonably easy, but I’ve got to do some handling. Now if I had a 16 cylinder turbo charged engine that weighs around about eight and a half tonne I don’t think I’d be looking to dismantle that tomorrow afternoon. So I’ve got to have some form or some way of knowing. You must start off with a base line and that’s where we’re really at now, is where do we start from? That’s our Just Noticeable Wear beginning. Another year, we might be able to tell you. Andrew Pearce: A few years ago when we were first talking to you about vehicles and oils and things like that and you were in the early stages of involvement with Penrite - we were talking about spectroanalysis of engine oils, which was one of the features that they were offering to you. I’m in an interesting position, where originally I was actually working with the South Australian railways - funnily enough on big 16 cylinder turbocharged diesel engines - and spent about six months of my electrical apprenticeship working in the chemical testing laboratory in the railways, �where funnily enough every week we were running big spectroanalysis test runs on all of the engine oils from the locomotives in the fleet. Are you planning on using things like the spectroanalysis results you’re getting back from engine oils to pick up the early stages of wear? Because that was one of the things that we were doing with the oils - you could see when the lead and copper and things like that started appearing. David Hallam: In theory it sounds great, but if something is corroding and it’s not moving, how do you analyse it? In order to use spectral analysis it needs to be running continuously. So I mean yeah, great, if we’ve got something in a display fleet that’s fine, but if it’s the prototype Holden and it’s on display in the Nation Gallery and it’s not running at the moment, how do we monitor it? Andrew Pearce: You don’t get the materials building up in the oil and you definitely don’t build up the base line enough to get a fingerprint of what’s normal. David Hallam: No. And it’s only done eight miles since it was rebuilt. So it most probably isn’t worn in. So you know, you’ll still be picking up all that first piece of a peak. So, we’ve got a long way to go. We’re just flagging it. Joanna Barr: Just a quick question. Is a maintenance regime such as you and Alison described going to work where there isn’t museum quality climate control and there are known condensation problems? David Hallam: Yes, it will, you just make it more often. Basically, well, it depends on your environmental corrosivity, so really you need to get some idea of that. You need some measurement of your environmental corrosivity and then you can start looking at that. Joanna Barr: Yeah, so in a regional country area where….. David Hallam: Yeah, well, six monthly, yearly, you know, up it like that. This is where you know, we think we’ll be down to five yearly maintenance cycles here, but we don’t know. We’re not there yet. Joanna Barr: So we are potentially looking at a system that is very manageable for a very volunteer [organization]? David Hallam: Yes, that’s the great thing Joanna Barr: Yeah. David Hallam: Yeah, it’s not new tech. Joanna Barr: It’s low tech. David Hallam: Yeah, you just change the oil, just use a different one. Joanna Barr: No, that’s great. � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Big Stuff 2004 Date A point or period of time associated with an event in the lifecycle of the resource 2004 Creator An entity primarily responsible for making the resource Alison Wain Article An article in a journal or periodical Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Corrosion, wear and corrosive wear; the story of lubrication systems in large technology object storage and use Creator An entity primarily responsible for making the resource David Hallam, David Thurrowgood and Col Ogilvie Date A point or period of time associated with an event in the lifecycle of the resource 2004 corrosive wear economic life functionality Just Noticeable Wear maintenance oil Operating Objects operation