Flat Glass Gauge - Information
Reflex Glass - allows light striking the area of the glass covered by liquid to pass to the interior of the gauge so the area appears dark. Light striking the open space above the liquid level is reflected back to the observer, so that area appears silvery similar to a mirror.

Transparent Glass - is used to see both the level of a liquid and its characteristics. Clear glass is mounted on the front and back of the gauge. This permits direct observation of such characteristics as color or the interface between two unmixable liquids in the same system.

Pressure @ Saturated Steam

Recommended Gauge Models1,2

Recommended Valve Models

Type of Valve/ Gauge Connection3

350 psi @ 431F

4804 or 4904

450 or 460

Rigid or Union

450 psi @ 456F


454 or 456

Stuffing Box7

650 psi @ 494F 4905 498 Stuffing Box7
485 498 Stuffing Box7
4946 498

Expansion Loop

1500 psi @596F 4886


Expansion Loop

1 Fire Box Quality steel plate chamber material is used on gauge Models 485, 494, and 488.
2 Mica shields are standard on all transparent models to protect the glass from condensate
which causes leaching of the glass except Model 490 and must be added at extra cost.
3 Expansion loops or stuffing box nipples are used to allow expansion caused by temperature variances.
4 Belleville washers are highly recommended at additional cost to reduce thermal effects on clamping
5 Belleville washers are required at extra cost to reduce thermal effects
6 Flange to flange assembly, which includes cranite gaskets, are required at extra cost.
7 Stuffing Box Nipples required at extra cost. The Model 498 valve must be ordered with a stuffing box.

Catalog Page 39
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