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Car Seal Working and Types

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Introduction:- Valves in chemical industries are the crucial component. We need valves to regulate the flow of fluid. In industry, some valves are very crucial so by changing its position without asking an authorized person can upset the whole process. So, we need particular seals for different indications that seals are known as Valve Car Seal.
Valve seals are simple devices to keep the valve in its open/close position and keep an unauthorized person away. To distinguish what kind of seal is fitted on the valve different color-coding is done. E.x. Red color indicates a closed valve, Green color indicates an open valve, etc. Sealed valve operation can take place only by cutting the seal which can show the try to tempt the process.
Construction
The seal head is made up of aluminum or zinc and the cable is made up of stainless steel because stainless steel offers great resistance to corrosion. Nowadays plastic valve car seals are also available in the market.
The cable is multi-threaded so it does not break in an accident. The length of cable must be long enough so it can be fit to the largest valve of the industry. The usual length of the wire is around 1000 mm. The diameter of the cable is between 1.5 mm to 5 mm.
Every car seal contains a unique identification number and has one tag which has critical information.
Types of car seal
1. Self-locking car seals
2. Breakaway key seal
1. Self-locking car seals
The self-locking car seals are only one time usable. As the cable enters the body of the car seal it can not be released. To open it we need to cut the cable.
Breakaway key seal
The breakaway key seal can be released after the cable enters the body. It is sealed after tightening the cable and the key will turn on and jammed the cable.
Working of car seal
To lock the valve we need to lock the handwheel or lever of the valve. The cable of the valve car seal is fitted in such a way that it locks the lever or handwheel of the valve and then it is entered into the seal body and fits inside it. The extra cable out of the body is cut down. To understand how car seals work and fitted watch this video.
What are CSO and CSC?
You must come across the term CSO and CSC on P&IDs many times. It is nothing but shows the position of the valve car seal. CSO indicates that the valve is locked by a car seal in an open condition and CSC indicates that the valve is locked by a car seal in close condition.


Post time: Nov-22-2021