Bar Breaking Apparatus
Product Code : LSK-PL-10352
Bar Breaking Apparatus (SKU LSK-PL-10352) is a heavy cast iron frame carrying a stout iron bar, used to show the very large forces produced when a metal bar expands and contracts with temperature. A nut at one end takes up the slack and the other end is drilled to take a cast iron breaking bar, which snaps as the heated bar cools. Science Lab Supplies manufactures the apparatus at its Plot 448, HSIIDC Industrial Area works in Saha, Ambala, supplying schools, colleges, tender contractors and distributors directly.
Specifications
The apparatus is built around a heavy cast iron frame that holds a stout iron bar. One end of the bar is fitted with a nut to take up slack, and the other end is drilled to accept a cast iron breaking bar, the piece that fails in the demonstration.
| Parameter | Value |
|---|---|
| SKU | LSK-PL-10352 |
| Frame | Heavy cast iron |
| Main bar | Stout iron bar |
| Tensioning | Nut at one end to take up slack |
| Breaking piece | Cast iron breaking bar, fitted through the drilled end |
| Manufacturer | Science Lab Supplies, Saha, Ambala, Haryana |
| Country of origin | India |
Applications and Experiments for the Bar Breaking Apparatus
Typically the iron bar is heated strongly, the nut is tightened to remove slack, and the bar is left to cool. As it contracts it pulls against the cast iron breaking bar until that bar snaps, showing how much force thermal contraction can exert. This is standard heat and thermodynamics lab equipment.
- NCERT Class 11 physics, thermal properties of matter: thermal expansion and thermal stress.
- Everyday engineering links: expansion gaps in railway lines, bridges and pipelines.
- B.Sc. and engineering physics: introducing thermal stress in a restrained bar.
Standard Scope of Supply
The apparatus is supplied as described above: the heavy cast iron frame with its stout iron bar and tensioning nut, drilled to accept a cast iron breaking bar. Because each demonstration breaks one bar, tell us how many breaking bars you want and they will be itemised on the quotation.
Packing, MOQ and Lead Time
One apparatus for a demonstration bench or several for a group of institutions can be quoted, each quotation giving packing, delivery time and price for the quantity. Spare breaking bars and other thermal-expansion items can be added to the same document.
Science Lab Supplies, an IEC-holding registered exporter, is able to ship to buyers in Zambia, Rwanda, South Africa, Qatar, Sri Lanka and Vietnam. The business is registered under Udyam as a manufacturing enterprise (UDYAM-HR-01-0014546) and for GST (GSTIN 06ADEPJ0574F2ZU). Ask for a quote on the contact page or through the enquiry cart, and see the lab tender page for tenders.
Frequently Asked Questions
What does the Bar Breaking Apparatus demonstrate?
It shows the large force produced when a restrained metal bar changes length with temperature. As the heated iron bar cools and contracts, it snaps the cast iron breaking bar held at its drilled end.
Why is the breaking bar made of cast iron?
Cast iron is brittle, so it fractures cleanly instead of bending when the contracting bar pulls on it, which makes the result dramatic and easy to see.
Is the demonstration hazardous?
Yes, it involves a very hot bar and a sudden fracture. A teacher should perform it, students should stand back, and eye protection should be worn.
Is Science Lab Supplies the manufacturer?
Yes. The frame and bar are produced at the company’s own factory in Saha, Ambala, India, so your quotation comes from the manufacturer and not from a trading firm.
Related Thermal Expansion Apparatus
These four Physics Lab items extend the lesson: a bimetallic strip and a ball-and-ring set for expansion of solids, a ring for comparing heat conduction in metals, and a kit for comparing material hardness. All four can be added to one quotation.
- Bimetallic Strip — 200 x 15 mm brass and steel strip on a wooden handle.
- Ball and Ring Apparatus — brass ball and ring on rods with wooden handles.
- Conductivity Ring — four metal strips on a ring with wax cups.
- Hardness Tester Kit — drop-weight rig with metal and Perspex samples.
Browse the full Physics Lab range or all physics lab equipment.
Last updated: 25 September 2026
