3B Scientific Thermal Expansion Apparatus D User Manual
3B SCIENTIFIC® PHYSICS
U15400 Dilatometer/linear expansion apparatus
Instruction sheet
3/03 ALF
®
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The dilatometer is for the proof and quantitative determination of linear expansion of solid materials as a
function of material, length and temperature.
1. Safety instructions
• Caution. The experimental procedure results in hot
steam.
• Do not touch heated tubes with your fingers. Use
cloths when replacing tubes.
• Do not subject the glass tube to mechanical stresses.
1 Fixed mount with screw for securing tube and securing screw
2 Screw for stand (see Fig. 2)
3 Base strip
4 Spring clip for securing hose
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Guide mount with gears for pointer
6 Testing tubes
7 Pointer
8 Scale
are three testing tubes made of steel, brass and glass.
Suitable for projection using a daylight projector (see
Fig. 2).
Dimensions: 730 mm x 50 mm x 200 mm
Scale dimensions: 140 mm x 200 mm
Scale: 140 mm x 200 mm
Measuring range: 1 mm
Accuracy: 0.05 mm
Length of tube: 650 mm approx.
Weight: 2 kg approx.
2. Description, technical data
The dilatometer consists of a base strip with fixed mount,
guide mount, pointer and projectable scale. Also included
Figure 1
3. Principle
To determine the linear expansion coefficient α for
various materials, it is necessary to measure the ex-
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pansion for a certain temperature rise ∆T. Thus the
tubes are heated to 100° C by means of steam and the
temperature difference ∆T from room temperature is
calculated. The expansion is determined from the
movement of the pointer, where a pointer movement
of 50 mm indicates an expansion of 1 mm. The expansion coefficient is determined from the length of the
tube ∆l between the two fixed points by means of the
formula:
∆
l
α
=
⋅
∆
lT
the fixed mount and secure it with the screw. The
screw should grip the ring nut of the tube.
• Hoses should be attached as in Figure 1 and the
run-off bowl should be placed under the hose.
• Adjust the point to zero if necessary.
Also required for heating the tube under test:
Vapor generator or a bunsen burner heating an Erlenmeyer flask
4. Instructions for use
• Attach the fixed mount at marking 200, 400 or 600.
• Attach the open end of the tube to be tested into
5. Storage
The glass tube should be secured beneath the base strip
to avoid damage.
Figure 2
3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com • Technical amendments are possible
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