Car audio mainly includes three parts: main unit, speaker and power amplifier. The mainframe is the most important part of the car's audio, just like the human brain, what kind of sound to make, is controlled by the brain. Currently popular hosts include CD host, MP3 plus CD disc box and CD/DVD/car MP5 console. MP5 console has replaced the general car CD audio system, and the massive hard disk capacity has replaced the traditional disc. Car MP5 has become the mainstream today.
Longkou Tongli Auto parts Co., Ltd. is located in Longkou City, Shandong Province, with fixed assets of 80 million yuan. Founded in 1995, the products related to automotive parts and accessories, hardware, household appliances, and mold processing and other related fields. The company covers an area of 120000 square meters, modernized standard factory building 60, 000 square meters. The company has 310 sets of processing equipment and 450 employees. In 2005, the company introduced and innovated the production and processing technology of steel thin-walled chrome plated cylinder liner. Taiwan's Da Qiao precision CNC machine tool, tl-55 thin-wall cylinder liner automatic chromium plating assembly line, Dahe double feed automatic honing machine, etc., has been equipped with advanced special testing instruments, mainly: Tokyo precision ma62012Ca-60h cylinder liner roundness tester. German Marm 2 type roughness tester, hvs-1000 digital display micro Vickers hardness tester, universal tensile force tester and time tt260 coating thickness tester, etc. The first stage of the project produces 500000 steel thin wall cylinder liners annually, which can provide suitable models for all kinds of engines with thin wall chrome plated cylinder liners. At present, the main products of the company are 4JB1、4JA1、4BD1、6BG1、4JH1、6112ZQ、C240、C190and other series products, which are suitable for the use of thin-walled chromium-plated cylinder liners. The hardness of the chromium layer of the inner hole of the thin wall chromium-plated cylinder liner is above HV800. The scattered point shaped sponge chromium layer of the inner hole of the cylinder liner is specially processed into a platform honing mesh structure with excellent oil storage performance, so that the chromium-plated cylinder liner series of products meet the quality standards of Euro II and Euro III. The wear resistance of the product is over 300000 km. At the beginning of 2006, the cylinder liner passed the quality inspection and appraisal of Shanghai Internal Combustion engine Research Institute. The company actively adopts the advanced international quality management system, and has passed theQS-9000 quality system certification and ISO/TS16949 international quality system certification of (CNAB) quality Certification Center (AQA).