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One of the welding methods that is widely used today because it is easier to operate, more practical in its use, can be used for all welding positions and more efficient is called Shield Metal Arc Welding (SMAW). In this welding, the base metal and filler metal will experience thermal cycles which lead to local heating and cooling processes resulting in residual stress and distortion in the material. This residual stress must be removed because it causes a decrease in the mechanical properties of the material. The most widely used method is the thermal method that is by Post Weld Heat Treatment (PWHT). The success of The post-weld heat treatment in removing residual stresses in PWHT is influenced by the holding time. This study aims to examine the effect of holding time on heat treatment, on the weld toughness of steel. In this study, the type of welding used was SMAW welding, the material used was steel AISI 4130, the electrodes used were LB-7018-1 standard application and AWS classification A5.1 E7018-1. The test holding temperature is 650oC. The holding time of testing uses three variables, namely: 2.5 hours, 4.5 hours, 6.5 hours. The Impact testing is done by the Charpy method. From this study, the influence of holding time variation on PWHT holding temperature on the weld strength of AISI 4130 steel was obtained.

The need of coconuts in Indonesia is relatively high. The use of large quantities of coconuts produces large amounts of organic waste from coco fiber, which tends to become waste if it is not used to be beneficial for humans.One of the potential uses of coconut fiber is as a reinforcement of natural fibers in polymer matrix composite materials. Recently, the applications of composite materials have been expanded widely including structural angine component which whitstand certain load like impact load. But most of them used synthetic fiber. Although the use of natural fibers as reinforcement in composite materials has been widely studied, their use is still limited because natural fibers have their own advantages and disadvantages. The purpose of this study was to measure the impact strength of specimens of coconut fiber reinforced polymer matrix composite material, and to determine the effect of the length and concentration of coconut fiber on its impact strength. A significant and valid regression model was also generated in this research, that states the relationship between fiber length and fiber content of resin matrix composite material to its impact strength. The result shows that the impact strength of the samples were influenced by fiber content and fiber length. The regression models for the impact strength of  resin composite reinforced with coconut fiber is Y = 4.44 +0.180 X1 – 0.52 X2  Where: Y = Impact Strength (kJ/m2), and X1= Fiber length (mm), and X2= Fiber content (%).

Gemba  kaizen  adalah  budaya  jepang  untuk  melakukan  perbaikan  dan peningkatan  secara  terus  atau  berkesinambungan  di  tempat  kerja.  Budaya  jepang  ini diterapkan  oleh  kebanyakan  perusahaan  jepang  di  dunia.  ISO  9001  sebagai  sistem manajemen kualitas yang dikeluarkan oleh badan Dunia IOS (International Organization for Standardization)  juga menekankan kepada organisasi mulai dari manajemen puncak sampai  ke  level  bawah  untuk  melakukan  peningkatan  berkesinambungan  (Contnuous Improvement),  yang  mana  hal  ini  tertuang  dalam  beberapa  klausul  ISO  9001. Diantaranya  klausul    4.1.f,    Klausul  5.4.1.b,  dan  Klausul  5.4.2.b  serta  ada  satu  kalusul khusus yang membicarakan tentang perbaikan berkesinambungan ini yaitu Klausul 8.5.1. Penelitian  ini  dimaksudkan  untuk  mempelajari  penerapan  gemba  kaizen    serta hubungannya  dengan  penerapan  continuous  improvement  pada  sistem  manajemen kualitas  ISO  9001.  Dari  hasil  penelusuran  literatur  didapat  bahwa  antara  gemba  kaizen dan  Continuous  Improvement  pada  sistem  manajemen  Mutu  ISO  9001  adalah  memang sejalan  sehingga  bagi  organisasi  yang  sudah  menerapkan  gemba  kaizen,  ketika  akan menerapkan  sistem  manajemen  kualitas  ISO  9001  sebenarnya  sudah  lebih  dulu meneruapkan  Continuous  Improvement  pada  Standard  sistem  manajemen  kualitas  ISO 9001, sehingga perusahaan itu akan sangat mudah beradaptasi dengan sistem manajemen mutu ISO 9001 baru diterapkan tersebut. Kata-kata kunci : Gemba Kaizen, ISO 9001, continuous improvement