NRS Non-Rising Stem Valve
An NRS (non-rising stem) valve is a gate valve whose stem turns in place and moves the gate inside the body when the handwheel is turned. Because the stem does not rise, the valve height stays constant and it fits tight spaces under ceilings and in pits.
The store range includes DIN flanged models in DN100, DN125, DN150, DN200, DN250 and DN300. As its position cannot be seen from outside, in fire systems it is usually combined with a post indicator or tamper switch.
Main Applications
- Underground hydrant network valves
- Sectional valves used with post indicators
- Under-ceiling and tight-space installations
- Pump room isolation valves
- Water tank outlet lines
Technical Data
| Type | Non-rising stem gate valve (NRS) |
|---|---|
| Size | DN100, DN125, DN150, DN200, DN250, DN300 (product range) |
| Connection | DIN flanged (product range) |
| Pressure class | By model (confirmed with flange PN class) |
| Body | By model (confirmed with manufacturer data) |
| Stem | Inside the body, non-rising |
| Operation | Handwheel or post indicator connection (by model) |
| Position monitoring | With tamper switch (supplied separately) |
Material Options
| Part | NRS valve |
|---|---|
| Body | By model |
| Gate | By model |
| Stem | Non-rising type (material by model) |
| End | DIN flange |
Which material? No reliable manufacturer datasheet was found for this valve; sizes are taken from store products, and material and pressure rating are confirmed by model.
Advantages
Constant Height
- Stem does not protrude
- Fits tight spaces
Suited to Buried Use
- Operated from grade with a post indicator
Full Bore
- Gate clears the flow when open
Large Sizes
- Up to DN300
Construction and Design Features
- Non-rising stem turning inside the body
- Gate travelling along the stem
- DIN flanged ends
- Stem top suited to handwheel or indicator
Write the DN size and operation method (handwheel or post indicator); we will quote the NRS valve with the right accessory.
How to Choose?
- Define the locationChoose a post indicator for buried valves and a handwheel in open areas.
- Select the sizePick the line size from DN100–DN300.
- Check the flange standardMatch the DIN flange PN class with the mating flange.
- Plan position monitoringAdd a tamper switch or indicator.
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Why ORFA?
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Details →Get a quote for your project
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