Questions to South African mining engineers

[KoTaZA]

Hi peeps,

New to the forum and to the South Africa mining sector, I don't really see a forum where the SA mining eng shares their experiences, so hopefully this can be a start where we share experiences and also socialize a bit.

Anyways, I will kick off with the following question, the SA regulations requires the usage of codes such as ASME VIII, B31.3 etc. for vessels and piping within petrol-chem plants, but what is typically used in the mineral processing plant in the mining sector?

It appears that there are really no codes that are required by regulations for equipment that are not under pressure, so typically OEM standards, and some safe engineering practices which varies depending on the designer, which is quite weird to me to be honest, I suppose the explanation is that the inherent risk is a lot lower than those in the petrol-chem industry. But what about those pressurized parts of the of the plant (e.g. pumped process water/fluid, chemicals etc...), is it common practice to use B31.3 for design and construction of those section or is it more common to use some other EN/ISO/SANS standards for these sections of the plant?

 

[Heaviside1925]

The wording of your question seems a bit confusing to me. Life-safety codes are commonly industry / usage specific but design codes, such as ASME B31.3 is not industry specific, so your question does not make sense to me. You also mention there are no codes concerning equipment not under pressure. Yes, there are many codes for both life safety and design codes that are applicable to equipment not under pressure. If SA regulators have adopted ASME as the standard, then it would follow that any industry using "raw, intermediate, and finished chemicals; petroleum products; gas, steam, air and water; fluidized solids; refrigerants; and cryogenic fluids. Also included is piping that interconnects pieces or stages within a packaged equipment assembly." would use this standard to design their systems. The last was copied directly from B31.3 and it makes no distinction for industry. If for some reason the mining sector falls under no SA regulatory authority, then it would likely be your company's underwriter that dictates what codes and standards need to be adhered to.

 

[KoTaZA]

Perhaps let me rephrase and go into a little more about SA's law regarding engineer design for pressurized equipment/piping.

SA have a PER (pressure equipment regulation) which is a SA law that governs everything above 50kPa (with some exceptions), it basically says such vessel/piping must be designed and constructed as per SANS 347 (a SA national standard) which further clarifies how pressurized equipment must be designed (e.g. by using a design code like ASME) and ensure conformance (e.g. using an approved 3rd party inspection authority like TUV).

And according to SANS 347 classification tables, for both dangerous and non-dangerous fluids, small size vessels and small bore piping system are classified as SEP (sound engineering practice) which essentially means these pressurized equipment are not covered by the law, so use 'best practices' to design and construct these.

Where it starts to get a bit more dicey is that there are some piping system (vessels too) that could be pretty dangerous but is classified as SEP in accordance to SANS 347 and thus are not regulated (e.g. 4" piping system at 1000kPa carrying leaching chemicals). My view is that for such system where leakages could cause serious injuries to staffs, spend the money and use something like B31.3 for the design, do the NDE and pressure test, get QC and AIA involve for such systems to ensure the quality of such system.

But of course, as per most things in life, higher quality mean higher costs, and everyone have their own views on what 'best practices' are and whether it is excessive to spend additional money on something that is not legally required. Hence I opened this post, hoping to get an idea on how the current SA mining engineers commonly approach such equipment/piping, do they go design code + QC, no code nor QC, or something in between (if so, what do they use?).

 

[LittleInch]

koTaZA,

I think you might be a bit disappointed in response on this forum.

It's very very quiet there - only a few posts in the whole of 2013.
A region based one is also difficult - not many SA's here

You could try posting in the boiler and pressure vessel forum instead.

I'm not familiar wih SA reg, but do you have a national safety body, like the HSE in the UK or similar?
Are they stuck in the dark ages and only get involved if a few people get killed on a regular basis?

Only when designers get sued or prosecuted for failing to apply sufficient best practice will things change.

My guess is that very few non SA people have any experience of SANS 347 so you would need to paste int he relevant tables for people to comment on.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Heaviside1925]

koTakA,
Thank you for your reply and I think I have a little better idea what you are after. Like LittleInch, I am also curious about other regulating bodies in SA. In the US we have multiple governing agencies, some of which create their own standards, while others point to professional standard organizations like ASME for guidance/adoption. That said, there are specific applications that fall outside scope ASME and in those cases guidance can be sought from certain trade groups or academic research or for a more arduous joinery, back to your engineering textbooks.

What I do have a problem with how you are viewing the term "SEP". I would not interpret this to mean no regulation but a statement about SANS 347 that is indicating the limits of the standard but still address the usage by saying you can't use this standard but you either need to start from scratch or use an alternative recognized standard for your design, such as ASME codes. To LittleInch's point, if these standards are not being enforced or companies in SA are allowed to make policies akin to "If it's not in SANS 347, then we don't need to engineer anything" then that is a difficult position to be put in to work as an engineer and I appreciate your frustration.

That said, as long as it's not mining specific such as "prescribed methods for longwall bracing" I'd be happy to point you to a number of internationally recognized standards for a specific application where-as I think any forum specific to your application would be happy to do the same. In the end, we are all engineers and to provide an engineered design we either needs the guidance of a standard or be able to apply the tools in our toolbox from experience and education to facilitate and communicate a design that is both safe and functional.

 

[KoTaZA]

LittleInch

Thank you for your reply, a lot of the other professions have a forum or chatroom where people within the industry exchanges information or experiences, but unfortunately it seems it is not quite the same in mining. SA does have some regulatory body that governs safety, but the committee only gets together a few times per year since the committee that put these regulations together are experts scattered across a lot of different industries and companies, so any response will normally take months, assuming it attracts a response. I will take your advice and see if I have better luck elsewhere.

Heaviside1925

Thank you for your replies, unfortunately it is explicitly stated in the SANS 347 that all things falling under SEP are not covered by the regulation and only requires 'best practices' to be used, I recall hearing that the classification tables in SANS 347 was based on what is in some European directives, so I suspect there are something similar in EU. I was from a Petro-chem background, so company standard back then was always use the most stringent requirement available as 90% of the design requires it and only 10% falls under SEP, which makes sense since it keep things simple, process streamlined and the cost increase is very minimal. But unfortunately it is the other way around for the mining industry, where 90% of the equipment does not warrant such design, so it gets a bit difficult sometimes to justify the additional spending especially if it is not legally required. But you raised a very good point, do you or other forum members have any ideas as to which standards does the mining engineers in US/EU generally frequents for things like piping and vessels? It would be a good idea to see what other mining engineers in different part of the world uses at their mines.

 

[Heaviside1925]

KoTaZA,
You keep giving more clues, so I am inclined to respond a bit further.

I am not trying to belabor this point but let me try to approach it differently. "explicitly stated in the SANS 347 that all things falling under SEP are not covered by the regulation and only requires 'best practices' to be used" I do not feel this statement excludes anything SEP from regulation, but it is telling you that you cannot use SANS 347 when evaluating the design. It also tells you, that usage, designated as SEP, does indeed need to be engineered. Now what the administrative body enforcing SANS 347 and what your company considers SEP to mean seems to be where you are running into your current frustrations.

I also appreciate your petro-chem background and understand it must be frustrating going from what is typically a highly regulated industry to one where "just make sure it doesn't blow up" is your only guidance. I have been in your shoes involving upstream oil and gas processing. An example would be where you are given a Chinese pump, a Swedish separator and a Canadian reactor and a pile of pipe and fittings, all fabricated per their own country's codes and regs and your management says, create a design to hook them up and make them work. You made the statement 90% of the design requires it and only 10% falls under SEP and it now sounds like you are working under the opposite ratio but to me, this is where your job can be challenging, educational and in my opinion one of the main reason our profession exists in the first place but can be very frustrating at the same time.

In reading the progression of these posts, it appears you started where most of us would start when given a design task. The question starts with something akin to "Who is the overall authority regarding mining and processing in SA and what standards/codes do they point to as design guidance?" followed by "What are my companies standards and guidelines?" Correct me if I am mistaken but I feel what you are communicating is that both the SA regulators and your company are pointing to SANS 347 and telling you that as long as that standard is meet, there are no additional guidance or standards that need to be meet and the question being posed to this forum is "What standards are typically used in the SA mining industry for designs that fall outside of SANS 347 or are designated SEP by SANS 347" I think what LittleInch was alluding to and what I will say out right is, I don't think you are going to find any. Outside of the actual extraction from the ground, the rest is just engineering and standard engineering practices driven by specific industry best practices. I have not been directly involved with extraction and I am not a mining engineer, but I have been involved with ore processing and refinement, which it sounds like the area in which you are seeking guidance. I cannot speak to where exactly to point you because I do not know which specific industry you are in aside from mining. Without further application specific information, I will point you to some areas that might assist you.

Your company's underwriter and the standards the underwriter may have dictated to your company.
SA standards such as fire, life-safety, environmental and electrical codes. These may not directly point to information you are seeking but many time reference other codes and guidance in their application.
Guidelines and best practices from recognized industry trade groups for the specific usage and application you are working with.
Standards and specifications that were used in the fabrication of your company's existing equipment. As an example, if all your equipment was fabricates using UE standards, then it may not make much sense to apply US standard for interconnections.
Interact with local fabricators, suppliers and contractors that work with your industry to see what standards they are used to seeing and working with.
You may have to accept that part of your job will be working with equipment that will likely be fabricated under multiple different standards and trying to figure out the best standards to use so it can all work together, which could involve you having to apply multiple different standards. Best not may be the easiest for engineering but may need to be the quickest, the most economical, maintainability, interchangeability, etc. with your end result being a safe and functional design.
Lastly, I will say that there is a part of engineering that some engineers hate, which is effective communication and education of management. An example would go something like this. Your management knows that buying a pressure vessel fabricated and certified under SANS 347 is a 40% cost adder to buying and vessel from another country. When you mention that your design needs be done in accordance with a specific standard, what they are hearing is that you want to drive the cost up by 40%. Standards may cause a design to cost more money, may add complexity to the design, may make sourcing and fabrication more difficult but when properly applied may do the opposite as well. This is where some back of a napkin calculations and interactions with local fabricator, supply houses and contractors can aid you in your request to be able to apply and possible adopt standards and guidelines for your company moving forward.

 

[Heaviside1925]

KoTaZA,
Let me give you an example of how I would write a question to a forum here based on one you provided 4" piping system at 1000kPa carrying leaching chemicals

Forum: Pipelines, Piping and Fluid Mechanics engineering

I am working for a company in South Africa, and I am designing a system for the transfer of XX% XXXX acid (I am assuming it's acid leaching). Neither SA nor my company have any design standards or guidance relating to this service. The piping will be interconnecting a pump fabricated to ISO XXXX to a custom fabricated atmospheric storage tank with XXX material of construction and XXX style flanges. The pump process specification are as follows.....

Can anyone point me to any industry specific guidance for the transfer, handling and storage of XX% XXX acid?
Can anyone recommend the standard they would use to design the piping to interconnect an ISO XXX pump and a storage tank with XXX flanges?

 

[KoTaZA]

Heaviside1925

Thank you for your responses, I think in my case, I will most likely go B31.3 for calcs, approved welders and WPS for the welds, % NDE plus internal QC. This way there should be good balance of costs and quality for such systems.