DIFFERENCE BETWEEN UL CERTIFIED & UL TESTING BUTTERFLY

DIFFERENCE BETWEEN UL CERTIFIED & UL TESTING BUTTERFLY VALVE

UL is a global independent safety science company offering expertise and covering fire-safe systems under many recognized jurisdictions.

At present scenario there are two types of UL valves floating in the market one is UL Certified valves certificated and approved by UL governing body, these valves are prepared and tested as per UL standard parameters and other is UL pressure tested valves which are normal butterfly valves and UL pressure is taken for hydrogen testing and rest of the parameters are of basic valve.

The main difference between UL Tested & UL Certified butterfly valve is as follows:-

1      UL Certified Valves – Can only be provided by vendor whose is having UL approved certificate from United laboratory (UL) provided for specific sizes, which were approved on testing.

UL Testing valves- Can be provided from vendor who is manufacturing Butterfly valve.

2      UL Certified Valves – Design parameters are strictly govern by UL -1091 standard.

UL Tested valves – Can Design as per standard design.

3    UL Certified Valves – certain sizes, rating, metallurgy’s approved under UL can only be used.

UL Tested valves: - Standard metallurgy.

UL Certified Valves – Testing is done under supervision of  UL appointed inspector with considering all the parameters also with pressure testing as mentioned in UL standard, the separate record have to be maintained for the same which are reviewed after every three months by UL authority. Any discrepancy could lead to dissolving of UL Certificate by United Laboratory.

In testing of UL Certified valves  along with pressure of 350 or 300 PSIG other parameters are also taken into consideration , Were as in UL Testing valves testing will be done only on UL pressure of 350/300 PSIG ,other parameters will be as per normal design standard.

The basic parameters being considered for UL Certified & UL Testing valves is given below are as follows:- PARAMETERS TAKEN FOR TESTING  IN UL CERTIFIED & UL TESTED VALVE
S.NO	PARAMETERS AS PER UL 1091	UL CERTIFIED	UL TESTED VALVE
1	Pressure Testing @350 /300 PSIG	YES	YES
2	TORQUE	YES	NO
3	MATERIAL	YES	NO
4	GEAR BOX SIZE	YES	NO
5	HAND WHEEL SIZE	YES	NO
6	SHEAR FORCE OF PIN	YES	NO
7	POSITION INDICATOR	YES	NO
8	SHAFT MATERIAL	YES	NO
9	UL MARKING	YES	NO