【正文】 “machine design”, Anthony Esposito, charles e., Merrill publishing pany, assurance and controlProduct quality is of paramount importance in quality is allowed deteriorate, then a manufacturer will soon find sales dropping off followed by a possible business expect quality in the products they buy, and if a manufacturer expects to establish and maintain a name in the business, quality control and assurance functions must be established and maintained before, throughout, and after the production speaking, quality assurance enpasses all activities aimed at maintaining quality, including quality assurance can be divided into three major include the following: ①Source and receiving inspection before manufacturing。③Quality assurance after control after manufacture includes warranties and product service extended to the users of the and receiving inspection before manufacturingQuality assurance often begins ling before any actual manufacturing takes may be done through source inspections conducted at the plants thatsupply materials, discrete parts, or subassemblies to manufacturer’s source inspector travels to the supplier factory and inspects raw material or premanufactured parts and inspections present an opportunity for the manufacturer to sort out and reject raw materials or parts before they are shipped to the manufacturer’s production responsibility of the source inspector is to check materials and parts against design specifications and to reject the item if specifications are not inspections may include many of the same inspections that will be used during in these are: ①Visual inspection。③Dimensional inspection。⑤Performance inspectionsVisual inspections examine a product or material for such specifications as color, texture, surface finish, or overall appearance of an assembly to determine if there are any obvious deletions of major parts or testingMetallurgical testing is often an important part of source inspection, especially if the primary raw material for manufacturing is stock metal such as bar stock or structural testing can involve all the major types of inspections including visual, chemical, spectrographic, and mechanical, which include hardness, tensile, shear, pression, and spectr5ographic analysis for alloy testing can be either destructive or inspectionFew areas of quality control are as important in manufactured products as dimensional are as important in source inspection as they are in the manufacturing is especially critical if the source supplies parts for an are inspected at the source factoryusing standard measuring tools plus special fit, form, and function gages that may dimensional specifications is critical to interchangeability of manufactured parts and to the successful assembly of many parts into plex assemblies such as autos, ships, aircraft, and other multipart and nondestructive inspectionIn some cases it may be necessary for the source inspections to call for destructive or nondestructive tests on raw materials or p0arts and is particularly true when large amounts of stock raw materials are example it may be necessary to inspect castings for flaws by radiographic, magnetic particle, or dye penetrant techniques before they are shipped to the manufacturer for final calling for burnin time for electronics or endurance run tests for mechanical ponents are further examples of nondestructive is sometimes necessary to test material and parts to destruction, but because of the costs and time involved destructive testing is avoided whenever include pressure tests to determine if safety factors are adequate in the tests are probably more frequent in the testing of prototype designs than in routine inspection of raw material or design specifications are known to be met in regard to the strength of materials, it is often not necessary to test further parts to destruction unless they are genuinely inspectionPerformance inspections involve checking the function of assemblies, especially those of plex mechanical systems, prior to installation in other include electronic equipment subponents, aircraft and auto engines, pumps, valves, and other mechanical systems requiring performance evaluation prior to their shipment and final form “modern materials and manufacturing process”Electrohydraulic drum brakes ApplicationThe YWW series electrohydraulic brake is a normally closed brake, suitable for horizontal is mainly used in portal cranes, bucket stacker/reclaimers’slewing YKW series electrohydraulic brake is a normally opened brake, suitable for horizontal mounting, employing a thruster as the foot controlling switch the operator can release or close the is mainly used for deceleration braking of portal cranes’slewing a nonoperating state the machine