BS EN ISO 148-2-2008 金属材料.夏比摆锤冲击试验.试验机的检验

标准号：BS EN ISO 148-2-2008
中文标准名称：金属材料.夏比摆锤冲击试验.试验机的检验
英文标准名称：Metallic materials - Charpy pendulum impact test - Verification of testing machines
标准类型：H22
发布日期：2009/3/31 12:00:00
实施日期：2009/3/31 12:00:00
中国标准分类号：H22
国际标准分类号：77.040.10
引用标准：ISO 148-1;ISO 148-3
适用范围：This part of ISO 148 covers the verification of the constructional elements of pendulum-type impact testingmachines. 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 analogously be applied to pendulum impact testing machines of various capacities and of differentdesign.Impact machines used for industrial, general or research laboratory testing of metallic materials in accordancewith this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements arereferred to as reference machines. Specifications for the verification of reference machines are found inISO 148-3.This part of ISO 148 describes two methods of verification.a) The direct method, which is static in nature, involves measurement of the critical parts of the machine toensure that it meets the requirements of this part of ISO 148. Instruments used for the verification andcalibration are traceable to national standards. Direct methods are used when a machine is beinginstalled or repaired, or if the indirect method gives a non-conforming result.b) The indirect method, which is dynamic in nature, uses reference test pieces to verify points on themeasuring scale.A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified byboth 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 takes into account the total energy absorbed in fracturing the test piece using an indirectmethod. This total absorbed energy consists of- the energy needed to break the test piece itself, and- the internal energy losses of the pendulum impact testing machine performing the first half-cycle swingfrom 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 canbe determined by the direct method (see 6.4.5), and- shock of the foundation, vibration of the frame and pendulum for which no suitable measuring methods andapparatus have been developed.