Recently, China National Heavy Duty Truck Group Jinan Haowo Bus Co., Ltd. (hereinafter referred to as Haowo Bus) filed a recall plan with the AQSIQ according to the requirements of the Regulations on the Management of Defective Automobile Product Recall, and decided to start from May 29, 2015. A total of 561 vehicles of the Yellow River brand of all 12 models produced from April 2013 to April 2015 were recalled. This is the second time that on May 19 this year, the AQSIQ issued a recall notice to the HOWO bus to inform them of the recall of the Yellow River brand school bus with some safety problems. What is plasma cutting?
Plasma cutting uses a plasma torch to cut metals of various thicknesses. The plasma cutter blows compressed air out of a nozzle at high speed and at the same time forms an electrical arc between the nozzle and the metal to be cut. The resulting plasma is hot enough to melt the metal and the speed ensures that the molten metal is blown away from the cut.
What is plasma? Plasma Cutter,Plasma Cutting Machine,MMA Plasma Cutting Machine,Industrial Plasma Cutting Machine Changzhou Edaweld Trading Company Limited , https://www.edaweld.com
The investigation team requested a recall after the investigation in Hunan. At the end of April 2015, the General Administration of Quality Supervision, Inspection and Quarantine received a report on the safety situation of the Yellow River brand school bus produced by the relevant departments of Hunan Province. The bureau then organized an investigation team to conduct on-site investigations, user return visits and road tests in Yiyang and Shuangfeng, Hunan. After analysis and demonstration by experts, it was confirmed that some models of the Yellow River brand school bus were defective.
On May 19, the General Administration of Quality Supervision, Inspection and Quarantine notified the producers to implement the recall in accordance with the Regulations on the Management of Defective Automobile Product Recalls.
On May 22, Howe Bus publicly stated that it had decided to implement a full recall of the problem vehicles in accordance with the National “Regulations on the Management of Defective Automobile Products Recall†and the “Recall Procedures for Automobile Products of China National Heavy Duty Truck Group†and apologized to the relevant users.
On the same day, HOWO Bus announced that the recalled school bus was 266 vehicles of the National III school bus (JK6560DXA3, JK6560DXAQ3) produced and sold from April 2013 to November 2014, mainly sold to Hunan, Hubei, Jiangxi, Anhui, Shandong, Six provinces in Heilongjiang.
Frequent security incidents were ordered to be stopped by the local authorities. However, some media noticed that Howow Bus repeatedly emphasized the “individual†and “case†phenomena when describing the three major problems in the recalled vehicles.
Is the fact really only an "individual" phenomenon? According to a number of media investigations, these defective school buses have been in the market for two years and have frequently experienced security incidents in Hunan and Heilongjiang provinces.
Liu Xiaonian, director of Hongyang Kindergarten, Yongfeng Town, Shuangfeng County, Hunan Province, said that after spending $140,000 in April 2013 to purchase a Yellow River brand school bus, the brakes were broken for the first time. After that, the ABS control box, Various parts such as the steel plate of the vehicle were replaced. Due to too many problems, the manufacturer replaced a new car in August 2013. Unexpectedly, the new car that has just been replaced has various problems such as the breakage of the shock absorber bracket and the fall of the bumper, and then contact the Haowo bus to ignore it.
Daqing Tianjiao Car Service Co., Ltd. of Heilongjiang Province recently introduced in an interview with the media that the company bought 8 “Yellow River†school buses in July 2013. In less than two years, there were 20 “needs. An urgent problem to solve." In the words of the driver, the car "has something wrong with the whole body." There was a school bus that had two consecutive traffic accidents and the driver and many students were injured. To this end, the education department of Daqing City ordered the Huanghe brand school bus to be out of service.
School bus quality control system needs to be improved According to the General Administration of Quality Supervision, Inspection and Quarantine today, the school bus in this recall has the defects of front wheel and brake hose interference, loosening of the steering wheel fixing bolt, and insufficient connection strength between the bumper and the car body. The producers are developing recall measures for the above-mentioned defects, and conduct free investigation and recall of vehicle defects in the scope of the recall to eliminate potential safety hazards.
The General Administration of Quality Supervision, Inspection and Quarantine said that the organization of defective product management centers and relevant local quality supervision departments will focus on the supervision of this recall and urge producers to carry out major safety hazard investigations.
Experts said that the incident fully exposed the problem of the delay or lack of supervision of school bus quality in China, and the school bus quality control system needs to be improved.
EDAWELD CO.,LTD
To properly explain how a plasma cutter works, we must begin by answering the basic question [What is plasma? In its simplest terms, plasma is the fourth state of matter. We commonly think of matter having three states: a solid, a liquid, and a gas. Matter changes from one state to the other through the introduction of energy, such as heat. For example, water will change from a solid (ice) to its liquid state when a certain amount of heat is applied. If the heat levels are increased, it will change again from a liquid to a gas (steam). Now, if the heat levels increase again, the gases that make up the steam will become ionized and electrically conductive, becoming plasma. A plasma cutter will use this electrically conductive gas to transfer energy from a power supply to any conductive material, resulting in a cleaner, faster cutting process than with oxyfuel.
The plasma arc formation begins when a gas such as oxygen, nitrogen, argon, or even shop air is forced through a small nozzle orifice inside the torch. An electric arc generated from the external power supply is then introduced to this high pressured gas flow, resulting in what is commonly referred to as a [plasma jet". The plasma jet immediately reaches temperatures up to 40,000° F, quickly piercing through the work piece and blowing away the molten material.
Plasma system components
Power supply -- The plasma power supply converts single or three phase AC line voltage into a smooth, constant DC voltage ranging from 200 to 400VDC. This DC voltage is responsible for maintaining the plasma arc throughout the cut. It also regulates the current output required based on the material type and thickness being processed.
Arc Starting Console – The ASC circuit produces an AC voltage of approximately 5,000 VAC at 2 MHz which produces the spark inside of the plasma torch to create the plasma arc.
Plasma torch – The function of the plasma torch is to provide proper alignment and cooling of the consumables. The main consumable parts required for plasma arc generation are the electrode, swirl ring, and nozzle. An additional shielding cap may be used to further improve cut quality, and all the parts are held together by inner and outer retaining caps.
September 10, 2021