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Active Contributor

Join Date: Apr 2008
Posts: 23

Regarding car seal open/lclosed valves (cso/csc)

04/17/2008 7:45 AM

I wanted to know how the "Car sealing" feature is achieved for block valves of PSV. What is the safety device used? Is it some kind of molten lead sealing? and where is it exactly done on the valve? i mean on the valve handle or stem? There is an earlier post about Car seal valves but it doesnt mention how this feature is achieved at the site.

Thanks

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Join Date: Dec 2007
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#1

Re: Regarding car seal open/lclosed valves (cso/csc)

04/17/2008 11:07 AM

The term "carseal" comes from the railroad industry. Railcars were loaded with goods. To assure that the goods were not tampered with, agents on the shipping end would but a wire though a hole in the handle and then through a hole in the car. They would then use a lead ball witha hole in it that each end of the wire was put through. A hand press would be used to squeeze the lead tight on the wires and imprint a a seal of the agency. If the wire where cut or the seal was broken, they knew the shipment was tampered with. Latter versions used stainless steel bands with serial numbers and codes on them.

In plants, were use the concept, but not always the exact form of the carseal. Valve manufactures now have holes cut in valve handles and tabs on the valve bodies. These holes can be lined up and wires, locks, chains, and other means can not be put on the valve to assure the valve is not tampered with. Or better stated, the valve is place in either the open or closed position and its position can not be changed without someones knowledge.

In the Lock, Tag, and try safety rules, the valves should have locks with strict controls on keys, this is a form of carsealing. This is to assure that there is no accidental opening that could harm PEOPLE. This is an engineered control with physical limits coupled with an administrative control of the keys.

Some valves must be open and closed only on specific orders. These valves do not require a full locking system so a tie wrap like those used to bundle wires securly can be used to assist the people in recognising that the valve can only be changed with permission. We call this an administrative control type carseal, because the plastic wire can be broken easily.

Each company must set up their own rules and extent of the carseal device, from huge chains to plastic wires.

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Active Contributor

Join Date: Apr 2008
Posts: 23
#3
In reply to #1

Re: Regarding car seal open/lclosed valves (cso/csc)

04/17/2008 11:57 PM

Thank you so much. This really helps. So basically, what i understand is that CSO/CSC is similar to LO/LC.. only the method of lockign the block valves is different.

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Anonymous Poster
#9
In reply to #1

Re: Regarding car seal open/lclosed valves (cso/csc)

07/18/2008 7:53 AM

How CSO/CSC done in Ball Valves

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#10
In reply to #9

Re: Regarding car seal open/lclosed valves (cso/csc)

07/18/2008 9:57 AM

Most new valves all have specially designed pieces that attach to the valve handle and the the valve body. These pieces can then have a lock or seal put on the that will not allow the valve handle to be moved.

Older valves can have the special pieces added or you could wrap a chain around the handle so that it can not be moved. Finally, safety supply companys have generic LOCK, TAG and TRY kits that will allow you to lock most anything.

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#2

Re: Regarding car seal open/lclosed valves (cso/csc)

04/17/2008 12:00 PM

It is common in pharmaceutical primary manufacture, among other industries, to have padlocks on those valves that are to be secured and only to be operated under carefully-controlled procedure using a supervisory key system and Permit-to-Work arrangements. Determination of which valves are to be locked forms part of the HazOp [Hazard and Operability] study, which is a routine practice these days in well-run process industries. On-line encyclopaediae have more to say on this subject of HazOps.

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Anonymous Poster
#4
In reply to #2

Re: Regarding car seal open/lclosed valves (cso/csc)

04/18/2008 6:03 AM

your on the right track but there is SOOO much more to it than what you can put into a small spave like these ones.

ifm they were still around i would have suggested the Ziess-Ikon locking system records department in Berlin Germany. since assa-abloy took the company and many others over much of that data seems to be unavaiable.

if you can do a bit of digging look for either the T.A.O.L. website and send a email to either ron mcguire or paul bentley both are able to send right of the top of their heads more than you will ever want to know about the subject of mechanical lock out systems under great grand master key systems for indusrial applications.

if they can't help ask for a current email address for The Instituional Locksmiths' Association.

'da ber

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#5
In reply to #4

Re: Regarding car seal open/lclosed valves (cso/csc)

04/18/2008 7:09 AM

Thank you everyone for these encouraging/ informative posts. yes, the subject is vast. I have procured Netherlocks interlocking systems for a client once for PSV block valves and simple pad locks numerous times for clients. But I think these methods of locking are indicated in the P&ID as "LO/LC" valves. I think CSO/CSC does not indicate the use of PAd locks or coded key lock method. It must be indicative of some other way of locking valves. Correct me if wrong.

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Guru

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#6
In reply to #5

Re: Regarding car seal open/lclosed valves (cso/csc)

04/18/2008 8:57 AM

Its all up to the user on how you define it. I've never seen a LO/LC except for in OSHA's Lock, Tag, Try system in plants. I could envision having LO/LC if you have batch operations and your clients need to assure that the batches of products are highly secured. Pipelines that leave the plants do use a LO/LC system because the public can get to them and tamper with the valve.

So the carseal program is where you have a controlled workforce and the valves are used frequently; this would be my base definition. LO/LC would be used when the people are uncontrolled or the valve is rarely if ever used.

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Associate
Safety - Hazmat - PHA / HAZOP Facilitator Engineering Fields - Chemical Engineering - Principal Engineer Engineering Fields - Piping Design Engineering - Chemical Process Engineer

Join Date: Mar 2006
Location: Billings, MT, USA
Posts: 54
#7

Re: Regarding car seal open/lclosed valves (cso/csc)

04/18/2008 11:06 AM

Vicini has done a nice job of explaining this. I would only add that the most significant difference between the Lock Open / Lock Closed (LO/LC) and the CSO/CSC is the method used to keep the valve in its documented position.

A hard lock forces a slightly more rigid removal procedure, but the intent is the same. These are methods for administratively controlling the opening or closing of a valve.

One common practice in HAZOP studies (as someone mentioned above) is to assume that any valve can be opened or closed at any time. A LO/LC or CSO/CSC removes this option. See OSHA 119.1910 for further discussion of HAZOP procedures (or pay some expensive consultant to do it for you www.bradleyventures.com - shameless plug).

In your original question, you reference a block valve on a PSV. Obviously, you would not want that valve closed if the equipment was running, so either method could be used here as long as the operator training covers the method for removing the lock or seal.

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Active Contributor

Join Date: Apr 2008
Posts: 23
#8

Re: Regarding car seal open/lclosed valves (cso/csc)

04/21/2008 12:17 AM

Thank you everyone for all your contributions to this post. It helped me clear my concepts. cheers!

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Anonymous Poster
#11

Re: Regarding car seal open/lclosed valves (cso/csc)

11/14/2009 11:33 AM

Use lockable valves

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Anonymous Poster (3); Nithya Iyer (3); PWSlack (1); StephanChE (1); vicini (3)

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