M00019327
New product
ISO DIS 148-2 2015 Edition, August 6, 2015 METALLIC MATERIALS - CHARPY PENDULUM IMPACT TEST - PART 2: VERIFICATION OF TESTING MACHINES
In stock
Warning: Last items in stock!
Availability date: 07/14/2021
Description / Abstract:
This part of ISO 148 covers the verification of pendulum-type
impact testing machines, in terms of their constructional elements,
their overall performance and the accuracy of the results they
produce. It is applicable to machines with 2 mm or 8 mm strikers
used for pendulum impact tests carried out, for instance, in
accordance with ISO 148-1.
It can be applied to pendulum impact testing machines of various
capacities and of different design.
Impact machines used for industrial, general or research
laboratory testing of metallic materials in accordance with this
part of ISO 148 are referred to as industrial machines. Those with
more stringent requirements are referred to as reference machines.
Specifications for the verification of reference machines are found
in ISO 148-3.
This part of ISO 148 describes two methods of verification.
1) The direct method, which is static in nature, involves
measurement of the critical parts of the machine to ensure that it
meets the requirements of this part of ISO 148. Instruments used
for the verification and calibration are traceable to national
standards.
2) The indirect method, which is dynamic in nature, uses
reference test pieces to verify points on the measuring scale.
A pendulum impact testing machine is not in compliance with this
part of ISO 148 until it has been verified by both the direct and
indirect methods and meets the requirements of Clauses 6 and
7. The requirements for the reference test pieces are found
in ISO 148-3.
This part of ISO 148 describes how to assess the different
components of the total energy absorbed in fracturing a test piece.
This total absorbed energy consists of
- the energy needed to fracture the test piece itself, and
- the internal energy losses of the pendulum impact testing
machine performing the first half-cycle swing from the initial
position.
NOTE Internal energy losses are due to:
- air resistance, friction of the bearings of the rotation axis
and of the indicating pointer of the pendulum which can be
determined by the direct method, and
- shock of the foundation, vibration of the frame and pendulum
for which no suitable measuring methods and apparatus have been
developed.