Durability test method

Abstract

The invention discloses a durability test method for a belt weigher. The durability test method is characterized in that type evaluation of durability of the belt weigher is conducted through high harsh-degree material experiments by simulating severe working conditions of the field in a laboratory. Compared with other known testing schemes, the durability test method has the advantages of fitting characteristics of a dynamic weighing machine and being close to field actual conditions of users, capable of being quantized and easy to reappear and just and fair as type evaluation and the like. Worldwide problems of type evaluation of the durability of the belt weigher are solved.

Description

technical field [0001] The invention relates to a durability test method for a continuous accumulative automatic weighing apparatus, in particular to a method for evaluating the durability of a belt scale by using a material test under simulated harsh working conditions. Background technique [0002] It is the basic requirement of users that products (components, equipment, systems, etc.) can reliably maintain performance and realize functions within their normal lifespan. People use reliability (reliability) to evaluate the ability of products to complete specified functions under specified conditions and within specified time. Durability is one of the three major elements of product reliability, which reflects the service life of the product to perform its normal functions; the other two elements are restorability and security. Repairability refers to the ability to quickly and easily troubleshoot a product if it fails, without high maintenance or repair costs. Safety in...

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Problems solved by technology

(2) Conveyor and Condition Effects .As a measuring instrument for continuous and automatic weighing of bulk materials during transportation, the belt scale is embedded on the belt conveyor, and the belt as a link to undertake and transmit gravity has a significant impact on weighing that cannot be ignored. The "weighing platform" is the tape in motion, which is neither an ideal rigid body nor a completely flexible body. It will show a "belt effect" during operation and produce unexpected additional force, which will distort the gravity during transmission; its work The on-site conditions are often very bad, and often cannot meet the relevant standard requirements of the belt scale manufacturer; even if the user's site is rebuilt and carefully installed and debugged, its status will still be lost quickly during use, so that it cannot provide stable and reliable measurement. Data; in actual work, factors such as material flow or abnormal changes in feeding volume will also affect the accurate measurement of belt scales

However, the above-mentioned method of on-site testing by users is only suitable for periodic evaluation of belt scales in use. If it is used as the basis for type evaluation, there are big problems because: (1) the type evaluation test has not been completed, and the manufacturing measurement has not yet been issued. It is not in compliance with the legal metrological supervision requirements to sell measuring instruments that have not yet obtained market access qualifications, and the measurement data obtained by them are not legally valid.

(2) The interval between the "first" and "final" tests should be several months. During this period, the EUT must continue to operate to complete a certain amount of delivery, but also ensure that the internal parameters of the machine are not changed without authorization, which is difficult to be rigorous. Supervision may also affect the normal use of users

(3) The on-site environment of any user is restricted by its specific process, and it is impossible to serve as a laboratory for type evaluation agencies for a long time, and it is difficult to completely replicate the environmental conditions of the belt scale to other environments. If the belt scales produced by various manufacturers If the scales are placed on the respective user sites for type evaluation, it will be unfair and just

(4) The durability test of the belt scale at the use site will be restricted by many conditions on site, such as the belt scale bandwidth, belt speed, range and other specifications, the test time and number of times, and the flow control of materials. Difficulty etc., and the measuring range or verification division value of the physical verification device on the user's site is often inappropriate, or it cannot be conveniently calibrated immediately, especially for high-accuracy belt scales (such as 0.2, 0.5), use It is very difficult to have a control scale that can meet the value transfer requirements on site, so that the test cannot be completed smoothly

[0008] From the above analysis, it can be seen that copying the test method of non-automatic weighing instruments or the test method carried out in the actual use field is not an appropriate method for the type evaluation of the durability of belt scales.

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