This
latter is really more dangerous than the former. As you would most
naturally conclude that your safety was getting weak, and about the
first thing you would do would be to screw it down so that the gauge
would show I00 before the pop would blow off, when in fact you would
have I00 or more.
So you can see at once how important it is that your gauge and safety
should work exactly together, and there is but one way to make certain
of this, and that is to test your steam gauge. If you know the steam
gauge is correct, you can make your safety valve agree with it; but
never try to make it do it till you know the gauge is reliable.
HOW TO TEST A STEAM GAUGE
Take it off, and take it to some shop where there is a steam boiler in
active use; have the engineer attach your gauge where it will receive
the direct pressure, and if it shows the same as his gauge, it is
reasonable to suppose that your gauge is correct. If the engineer to
whom you take your gauge should say he thinks his gauge is weak, or a
little strong, then go somewhere else. I have already told you that I
did not want you to think anything about your engine-I want you to know
it.
Pages:
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80