Gauge syphons from CMT Engineering
Gauge syphons are essential for the protection of sensitive instrumentation on steam lines and other pressure equipment. We manufacture both U syphons and ring syphons in the West Midlands, UK.

U syphons from CMT Engineering are manufactured in mild steel, 316L stainless or brass. They are available in sizes 8mm (1/4″), 10mm (3/8″) and ½” (15mm). Other wall thicknesses and materials are available on request.
Our standard pattern for U syphons is screwed BSP taper/BSP parallel, fitted with two back nuts on parallel end. Special patterns are available on request.
NPT (National Pipe Taper standard) threads are also available on request.
The maximum recommended pressure rating for our U syphons is 16 bar with steam up to 260 degrees C.
See also: ring syphons.
U syphons: dimensions and weights chart
| Nominal bore (metric) | Nominal bore (imperial) | Length dim. A | Length dim. B | Length dim. C | Length dim. D | Length dim. E | Weight each including nuts |
| 8mm | 1/4″ | 154.5mm | 68.5mm | 86.0mm | 132.0mm | 38.5mm | 0.34kg |
| 10mm | 3/8″ | 163.0mm | 73.0mm | 94.5mm | 136.5mm | 40.0mm | 0.43kg |
| 15mm | 1/2″ | 210.5mm | 91.5mm | 124.0mm | 174.5mm | 55.0mm | 0.63kg |
New data sheet coming soon:
