Another steam trap (Ray's patent)
Another steam trap (Ray’s patent). Valve, a, closes and opens by longitudinal expansion and contraction of waste-pipe, A, which terminates in the middle of an attached hollow sphere, C. A portion of the pipe is firmly secured to a fixed support, B. Valve consists of a plunger which works in a stuffing-box in the sphere, opposite the end of the pipe, and it is pressed toward the end of the pipe by a loaded elbow lever, D, as far as permitted by a stop-screw, b, and stop, c. When pipe is filled with water, its length is so reduced that valve remains open; but when filled with steam, it is expanded so that valve closes it. Screw, b, serves to adjust the action of valve.
Only the input is driven; every other part of this model moves by physics (MuJoCo), and its ratios are measured. Run it live, change its parameters, or switch the friction off to see the output stop.
- Modelled as
- Side view, as Brown, gravity on. The waste-pipe A (30 cm from the clamp B to its end in the hollow sphere C, brass, alpha 1.9e-5 /K) is a heat-to-length rod (openspec add-vessel-heat, `vessels.rods`): its free end on a slide, pushed like a spring of E A / L (1e5 N/m) toward 30 cm alpha (T - 293 K) at the temperature of its bore (a heated chamber, C 8 J/K, H 10 W/K; the steam's heat 800 W while the hand's cock is open). The plunger a works in a stuffing-box opposite the pipe's end, pressed toward it by the loaded elbow lever D, held off by the stop c (its joint limit) and set by the screw b; the valve's opening is the gap between the pipe's end and the plunger (0.3 mm cold). The pipe meets the plunger only by contact and pushes the lever off its stop. Water from the coil (2 kPa) runs through the bore, the gap, into C and out.
- Measured
- tests/test_heat_length.py (bare rod: end at length alpha dT within 1%, back to 0 cooled; trap: over 355 K valve flow < 1e-5 kg/s, the lever pushed off its stop, the end at the plunger; under 300 K valve open > 0.008 kg/s, lever on its stop, water out of C; free end at length alpha dT within 5% of the gap; water conserved < 1e-6 kg)
- Notes
- Grade B. True to scale the pipe's growth (0.42 mm) and the lever's give are under a pixel (gate WARN: pipe, lever never move on screen); what shows is the cock, the bore water, and the water in C and its stream stopping hot and running cool. The heat is not drawn. Elastic rod, one uniform temperature along it.
Film (MP4) · Still (PNG) · Spec (YAML) · Model (MJCF)
