Quick Answer: Lagged Pipe Apparatus finds the resultant thermal conductivity of lagging materials packed between three concentric GI pipes, 1 metre long, heated by a central nichrome wire cartridge heater. Temperatures are read on a multichannel digital indicator (0 – 300 °C) using Cr/Al thermocouples.
Last updated: October 2026
Key Features
Three concentric GI pipes on a stand, with two different lagging materials between them
Nichrome wire cartridge heater placed centrally
Single phase dimmerstat, voltmeter (0 – 250 V) and ammeter (0 – 2 A) on the control panel
Thermocouples on the pipe surfaces for intermediate temperatures
Technical Specifications
Specification
Value
Innermost GI pipe
6 cm outer diameter
Middle GI pipe
8.5 cm mean diameter
Outermost GI pipe
10.7 cm inner diameter
Length of pipes
1 metre
Heater
Nichrome wire cartridge heater, placed centrally
Voltmeter
0 – 250 V
Ammeter
0 – 2 A
Temperature indicator
Multichannel digital, 0 – 300 °C, Cr/Al thermocouples
Electric supply
A.C. single phase 230 V
Floor area
1.5 m x 1 m x 0.5 m high
About This Product
The space between the innermost and middle pipes is filled with one lagging material and the space between the middle and outermost pipes with another, so heat from the cartridge heater crosses both layers in turn. Using the heater input from the voltmeter and ammeter and the surface temperatures from the thermocouples, the resultant conductivity of the materials is found. This HEAT TRANSFER LAB unit needs a 230 V single phase supply and a floor area of 1.5 m x 1 m.
Frequently Asked Questions
Q1. How many lagging materials does the apparatus use? Two: one fills the space between the innermost and middle pipes, and another fills the space between the middle and outermost pipes.
Q2. What instruments are on the control panel? A single phase dimmerstat, a 0 – 250 V voltmeter and a 0 – 2 A ammeter, with a multichannel digital temperature indicator (0 – 300 °C) using Cr/Al thermocouples.
