Description
Product Overview
Spirax Sarco Double Window is a sight glass designed for pipeline fluid monitoring. It provides visual confirmation of flow conditions, allowing operators to detect blocked valves, strainers, or steam traps, and to inspect fluid color across different process stages.
Key Features
- Smooth concentric reduction in the inlet connection promotes turbulence for easier fluid detection.
- Constructed with brass bodies for 1/2” to 1” sizes, and bronze bodies for 1 1/4” to 2” sizes.
- Equipped with toughened soda lime glass windows conforming to BS 3463.
- Sealed with reinforced exfoliated graphite gaskets.
Technical Specifications
| Specification | Value |
|---|---|
| Sizes | 1/2”, 3/4”, 1”, 1 1/4”, 1 1/2”, 2” |
| Pipe Connections | Screwed BSP T Rp (ISO 7-1) or NPT |
| Body Material (1/2” to 1”) | Brass (EN 12165 CW617N) |
| Body Material (1 1/4” to 2”) | Bronze (BS EN CC491K) |
| Bezel Material | Brass (EN 12165 CW617N) |
| Window Material | Toughened soda lime glass (BS 3463) |
| Gasket Material | Reinforced exfoliated graphite |
| Maximum Allowable Pressure (PMA) | 5 bar g @ 90°C |
| Maximum Allowable Temperature (TMA) | 148°C @ 3.5 bar g |
| Minimum Allowable Temperature | -29°C |
| Maximum Operating Pressure (PMO) | 3.5 bar g (saturated steam service) |
| Maximum Operating Temperature (TMO) | 148°C @ 3.5 bar g |
| Minimum Operating Temperature | 0°C |
| Cold Hydraulic Test Pressure | 7 bar g |
Applications
- Monitoring discharge on the outlet side of steam traps.
- Detecting blockages in pipeline equipment such as valves and strainers.
- Visual inspection of fluid color at various process stages.
Installation and Maintenance
Sight glasses should have stop valves fitted on both the inlet and outlet. The upstream stop valve must be closed first to prevent overpressurization. The unit can be fitted in either a horizontal or vertical line on the outlet side of a steam trap. If the trap is a blast discharge type (e.g., thermodynamic), the sight glass must be fitted at least 1 m (3.28 ft) from the trap to protect the glass from thermal shock or pressure.
Available spare parts include the set of windows and gaskets, and the set of gaskets alone. When renewing windows and gaskets, ensure a gasket is fitted to either side of each window. The bezel must be tightened to a recommended torque of 60 - 65 N m (44 - 48 lbf ft).