NRS means Non–Rising Stem. OS&Y means Outside Stem and Yoke. In an NRS valve, the stem will turn to open and close the gate, but the stem does not move up or down as it turns.

NRS gate valve is developed to be used as the cut off and zone control valves in order to substitute supervisory switched butterfly valves and OSY rising stem valves in the fire security systems. These valves are usually burried underground to prevent the risk of freeze. Just to make them visible and traceable inside the systems, they are preferred to be used with post indicators instead of wheels. Valves could be commanded to get on/off by using post indicators and the valve positions could and traced.

Advantages: Smaller than pressure reduce control valves, and easy maintenance.

Disadvantages: Bigger than some valves which is using in fire fighting systems, and non-economic than the others.

Connection Type: 
Flanged

Working Pressure: 
200psi ~ 300psi

Maximum Working Temperature: 
0.6°C – 52°C

Dimension: 
2 ½” – 16”

Material Features: 
– Body: ASTM A 536 Noduler Cast iron
– Cover ASTM 536 Nodular cast iron
– Spindle: ASTM AISI420 Stainless steel
– Slide: Covered by EPDM nodular cast iron
– Gasket: EPDM
– O-ring: EPDM

Application Areas: 
In fire fighting systems, which is non-affected by freeze, than they are using under the soil.

Approvals:
– UL Listed
– ULc Listed
– FM Approved