Purpose and Application
The conical mandrel bending tester, Model 312, is designed to assess the flexibility and adhesion properties of coatings under bending stresses. It complies with ISO 6860, EN ISO 6860, and ASTM D 522 standards.

Test Principle
The test determines the largest diameter of the cone at which the coating shows signs of cracking or flaking after bending.

Description
The Model 312 is a compact, robust instrument made of enamelled steel, suitable for table-top use. It features a stainless steel conical mandrel and a pivoted pressure roller. The clamping device includes a cam lever for easy specimen changes.

Test Procedure
1. Turn the bending lever towards the clamp until it reaches the stop.
2. Insert the test sheet with the coated side outward between the cone and pressure roller.
3. Secure the specimen using the cam lever.
4. Optionally, insert a layer of paper to protect sensitive surfaces.
5. Bend the specimen by turning the lever around the mandrel smoothly over 2 to 3 seconds.
6. Examine the coating for cracking or flaking.
The test result is the length of cracking or the mandrel diameter at the end of the crack.

Technical Data
Dimensions: 250 x 140 x 420 mm
Net weight: 5.6 kg
Specimen thickness: 1/32" (0.79 mm)
Max. specimen width: 190 mm
Conical mandrel range: 1/8 - 1 ½" (3.2 – 38.1 mm)

Order Information
Order No. 0002.01.31 - Conical Mandrel Bending Tester, Model 312

Note: Specifications are subject to technical modifications.