Slide Charts

Slide charts are specialized slide rules usually made from thin plastic or cardboard stock. Many of these calculators have both a practical and marketing purposes - and some are extremely useful.

 HP Side       LP Side

This copper tube sizing calculator was given out at an gas industry conference in 1998 or 1999. The high pressure side calculate tubing sizes for 2 and 5 psig systems; the low pressure side if for sizing systems operating as 14 inches water column or less.

 
  Front         Back

The Daniel orifice flow calculator was made in the late 1970s by Datalizer. One side is designed for air-gas calculations, the other side for steam and liquids. For a gas, the required beta ratio of the orifice meter is calculated based on the pressure differential, flow rate, pipe size, gauge pressure, flowing temperature and specific gravity.

 Specs        Calculator

This simple card stock slide chart from Dresser Industries helped engineers select Roots rotary gas meters. One side uses metering pressure and flow to select a particular model number; the other side gives important specifications for the meter selected in the top window. The calculator has C and D scales for simple multiplication and division problems.

 Steam-Gas Liquid

Masonneilan (or Mason Neilan, then a division of the Worthington Corporation) copyrighted this plastic slide chart calculator in 1957. Its purpose was to calculate flows of gases, liquids or steam based on Cv or size and type of valve.

 Top             Back

Inside

National Fuel had the American Slide-Chart Corporation print this "Equivalent Energy Cost Calculator" in 1992. Based on the cost of any one of a number of different forms of energy (natural gas, electricity, propane, coal, oil (#2 and #6), gasoline and diesel fuel), one can calculate the dollars per equivalent BTUs for the others forms.

This marketing slide chart is getting a bit out of date; for gasoline, the calculator only goes up to $3.50 per gallon.

Front           Back

This well made 1965 slide chart by the Tube Turns division of Chemetron Corporation Lines" had some potentially useful information for the designers of regulator and metering stations in the form of fitting and valve losses as equivalent lengths of straight pipe. The front side is a velocity and pressure drop calculator for liquids, gases and steam; the back side calculates a friction factor correction based on a calculated Reynolds number. Calculations are valid for turbulent flow only.