Petroleum (Consolidation) Act 1928

Heating Vessel

The heating vessel or bath consists of two flat-bottomed cylindrical copper vessels placed coaxially one inside the other and soldered at their tops to a flat copper ring, greater in outside diameter than the larger vessel and of smaller inside diameter than the smaller vessel. The space between the two vessels is thus totally enclosed and is used as a water jacket.

An ebonite or fibre ring of right-angle section is fitted into the hole in the centre of the flat ring forming the top of the bath and, when the apparatus is in use, the oil cup fits into, and its flange rests upon, this ebonite or fibre ring so that the oil cup is centrally disposed within the heating vessel. The ebonite or fibre ring is secured in place by means of six small screws having their heads sunk below the surface of the ring, to avoid metallic contact between the bath and the oil cup.

A split socket, similar to that on the cover of the oil cup, but set vertically, allows a thermometer to be inserted into the water-space. A funnel and overflow pipe also communicate with the water-space through the top plate and two loop handles are provided thereon.

—	Dimension.	Tolerance.
Inner vessel:
Thickness	24 I.W.G.	—
Internal diameter	3"	±0.05"
Internal depth	2.5"	±0.05"
Outer vessel:
Thickness, not less than	24 I.W.G.	—
Internal diameter	5.5"	±0.1"
Internal depth	5.75"	±0.1"
Top plate :
Thickness, not less than	20 I.W.G.	—
Outer flange projection	0.375"	±0.1"
Diameter of central hole	To suit ebonite or fibre ring. Clearance not to exceed 0.1".	—
Ebonite or fibre ring :
Internal diameter	Easy fit on oil cup	—
External diameter of flange	2.75"	±0.02"
Overall depth of spigot	0.25"	±0.02"
Thickness, flange and spigot	0.08"	±0.005"
Screws, C.S.	8 BA. X 0.15"	—
Thermometer socket:
Internal diameter	0.6"	±0.01"
Height from top of plate	0.75"	±0.05"

The bath rests upon a cast-iron tripod stand, to the ring of which is attached a cylindrical copper jacket not less than 24 I.W.G. flanged inwards at the top, and of such dimensions that the bath, while resting firmly on the iron ring, just touches with its outward projecting flange the inward-turned flange of the jacket. Two handles are provided on the outer jacket.

Diameter of the outer jacket 6.5 inches + 0.1 inches.