• 한국물환경학회지
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• 제20권2호
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• pp.163-169
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• 2004

Feasibility of using PE sheet laminated CSP(Corrugated steel pipe) to sewers were tested via corrosion and abrasion tests for PE sheet laminated CSP; 1) corrosion test for PE film and PE coated plate, 2) corrosion test for joint of PE sheet laminated CSP, 3) corrosion test for outside of PE sheet laminated CSP, and 4) abrasion test for inside of PE sheet laminated CSP. The results for the corrosion and abrasion tests are as follows. 1. Results for corrosion tests on PE films and zinc coated steel plates that were coated with PE films show that the surfaces of both PE were not changed compared to those of original PE samples. Furthermore, PE films maintained strong adhesion on the steel plates even though they were exposed to sewage and seawater provided cutting planes of the steel plates were treated with molding. But, results for corrosion tests on the spots that were previously cut off by a knife and a cutting planes of the steel plates were treated without molding show that steel plates have been corroded if they were exposed to sewage and seawater. 2. Results for corrosion tests on joints of PE sheet laminated corrugated steel using sewage show that gathering rust was observed at cutting plane of PE sheet laminated corrugated steel after 180 days, but PE film was not flaked off. However, PE film at cutting plane was flaked off when PE sheet laminated corrugated steel was exposed to seawater. Furthermore, flaking process was severely progressed at lockseam points of which the surfaces were not smooth. 3. Results for laying PE sheet laminated corrugated steel under the ground show that the surface of untouched PE film was almost identical to that of original PE film. However, the spots that were previously cut off by a knife and a cutting plane of PE sheet laminated corrugated steel have flaked off. 4. As a result of abrasion tests conducted with PE sheet laminated corrugated steel and sand, brilliance and thickness of PE was not greatly changed under the severe abrasion conditions. Therefore, the durability of PE sheet laminated corrugated steel for abrasion was determined to be good.

• 대한기계학회논문집A
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• 제31권3호
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• pp.403-408
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• 2007

The concrete pipe(Hume, PC) and polyethylene(PE) pipe are usually used for dram pipe in local market. Hume pipe, however, is heavy and needs the high cost of construction and PC pipe has a disadvantage to easily occur the deformation by the outside pressure even though it is light and constructible. The corrugated steel pipe coated with polyethylene is used increasedly because it is durable, constructible and economical. However, it is not used for sewage or waste water because it is hard to guarantee the watertight property on the coupling part. In this study, we studied on the flange coupling and the method of its construction to guarantee the watertight property and easy to use. If the developed flange coupling and method are used on a construction field, the economical property, constructible property and structural safety can be guaranteed.

• 지질공학
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• 제25권1호
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• pp.131-148
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• 2015

본 연구는 지열시스템 열교환 효율의 개선방안을 모색하기 위한 것으로 금속재질의 열교환기인 동관 및 스테인레스관과 기존 지열시스템에 많이 적용되는 PE관을 이용하여 지열열교환기의 재질에 따른 열전달 효율을 비교 분석하였다. 또한 지하매질의 지하수에 포함되어 있는 지하수열을 동시 활용할 경우의 열전달 효율 변화를 평가하고 그 적용성을 검토하였다. 열교환기 내의 유속, 유량 및 열교환기의 구경을 조절함으로써 열교환기의 재질에 따른 열전달 효율을 평가 후 현장실증시험 설계인자를 도출하였다. 열교환 효율과 유효 열전도도는 현장 열전달 효율 시험 및 열응답 시험을 통해 변화양상을 분석하였다. 분석결과 금속재질이 PE관에 비해 높은 열전달 효율을 보였으며, 유량에서의 구경증대에 따른 열전달효율은 크지 않았으나 유속에서의 구경증대에 따른 열전달효율은 높아지는 것을 확인하였다.

• 생물환경조절학회지
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• 제21권4호
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• pp.372-378
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• 2012

본 연구에서는 화력발전소에서 온배수의 형태로 배출되는 폐열을 히트펌프의 열원으로 이용하여 온실의 난방에 활용할 수 있는 히트펌프 시스템을 설계 제작하였으며, 난방 성능을 분석하여 PE 파이프 열교환기의 설계기준을 제시하고자 하였다. PE 파이프 열교환기의 내경은 20mm, 두께는 2mm였으며, Roll의 직경은 1,000mm로 하였다. 연구결과 PE파이프 열교환기의 적정 길이는 1.0RT당 75m로 설계하는 것이 바람직할 것으로 판단되었으며, 이때 히트펌프시스템의 난방성능계수(COPh)는 3.8로 나타났다.

• 한국화재소방학회논문지
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• 제34권1호
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• pp.18-25
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• 2020

본 연구에서는 보온재의 설치 상태를 고려한 ISO 20632와 NFPA 274 시험 기준에 따른 발열량 산출 결과를 분석하였다. 이를 위해서 보온재 총 6종(은박 발포폴리에틸렌(PE(S)), 무은박 발포폴리에틸렌폼(PE(N)), 고무발포(Rubber), 일본-폴리에틸렌폼(PE(J)), 일본-폴리우레탄폼(PU(J)) 그리고 일본-스티로폼(ST(J)))에 대해서 EN 13501-1과 화재성장곡선에 따른 난연 등급을 구분하였다. 그 결과 PU(J), PE(J) 그리고 PE(N)는 Class E 및 Ultra-fast, NFPA 274 시험기준에 의한 PE(S)는 Class D 및 Fast, ISO 20632에 의한 PE(S)는 Class C 및 Slow, 그리고 Rubber와 ST(J)는 Class B 및 Slow로 나타났다. 하지만, 난연 등급 평가 기준인 최대 발열량에 대한 시간평균 기울기는 시험 방법에 따라서 동일 보온재에 대하여 다르게 나타났으며, 보다 정확한 원인을 분석하기 위한 기초 연구가 필요한 것으로 판단된다.

• 설비공학논문집
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• 제24권2호
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• pp.183-189
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• 2012

Most of the domestic residential buildings have used the traditional radiant heating system, circulating hot water through the cross-linked polyethylene(PE-X) pipe buried in the floor panel of the heating space. New type of the heating panel was recently developed using heat pipes with double wicks. Some experiments were carried out in this study to verify the thermal characteristics of this heating system at the unit heating space which surrounded by outer space whose temperature of air be maintained scheduled value with time. Through the various experiments with several parameters, such as flow rate, inlet and outlet temperatures of hot water and the heating duration and so on, we found that the floor heating system with heat pipes was able to reduce the pumping power for hot water circulation by 4~31% compared with the conventional panel heating system using PE-X pipe. These results could be used for optimal design and efficient operation of the heating system as well as improvement of thermal comfort.

• Environmental Engineering Research
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• 제19권3호
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• pp.275-281
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• 2014

Aim of this study was to investigate biofilms attached in pipeline of water reuse from the MBR system treating sewage without chlorination in correlation to the outflow water quality. Two general pipe materials: polyvinyl chloride (PVC) and polyethylene (PE) were employed in the experiment. The peak growths were found at week 4 in both pipes. The maximum biofilms in PE pipe was $33mgVSS/cm^2$ with the growth rate of $4.75mgVSS/cm^2-d$ which was significant higher than that of PVC pipe. Biofilms examined by PCR-DGGE technique revealed five bacterial species in PE biofilms namely Sinorhizobium medicae WSM419, Sinorhizobium fredii NGR234, Geobacter sp. M18, Parachlamydia acanthamoebae UV-7, and Mycobacterium chubuense NBB4. The VSS concentrations in outflow had directly correlated to the biofilm attachment and detachment. High COD concentrations of outflow appeared during biofilm detaching phase. In summary, water quality of reuse water corresponded to the biofilms attachment and detachment in the pipeline.

• 한국가스학회지
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• 제11권3호
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• pp.49-55
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• 2007

폴리에틸렌(PE) 배관은 시공이 편리하고 강관에 비해 가격이 저렴하기 때문에 저압 공급용으로 많이 사용하고 있다. 본 연구에서는 유한요소 해석을 이용하여 매설한 PE 배관이 다양한 외부하중을 받는 경우에 발생하는 응력 및 변형에 대하여 알아보았다. 배관 직경이 $50{\sim}400mm$인 PE 배관에 대하여 매설 깊이를 $0.6{\sim}1.2m$로 달리하고 그리고 공급압력을 $0.4{\sim}4bar$로 변화시켰을 때 배관에 발생하는 응력을 유한요소를 이용하여 계산하였다. 결과적으로 매설 상태에서 각 하중 조건에 따른 응력 상태 그리고 복합적인 하중이 작용할 경우에 400호 배관에 발생하는 응력을 계산한 결과 매설 깊이가 1 m일 때 최대 원주방향 응력이 가장 작은 값을 나타내었다.

• 한국안전학회지
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• 제26권6호
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• pp.45-53
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• 2011

This study was performed to develop repair and reinforcing materials in sewage drain pipe by using 40% of CAC(Calcium Aluminate Cement) and 4% of Polymer Powder. Regarding reinforcing materials to enhance load-bearing capacity, polyester textile and wire mesh were adopted and then they were evaluated by the measurement of deflection and Stress-strain Relationship. Two types of drain pipe made by concrete and PE were considered as plain specimens and then loading test were performed after repaired by CAC mortar impregnated reinforcing materials. As the test results of the load-bearing test on both drain pipe, there was higher load-bearing capacity on the specimen adopted wire mesh but debonding of repair mortar was found due to stiffness of wire mesh. By the way, repair system using CAC mortar impregnated polyster textile without wire mesh showed satisfactory results including bonding and load-bearing capacity regardless substrate, so this repair system using by mixture of CAC mortar and polyster textile is suggested as the reasonable repairing method within this experimental scope.

• Journal of Welding and Joining
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• 제29권1호
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• pp.85-89
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• 2011

Waste water is disposed to sewage disposal plant by underground PE double wall pipes. Various processes have been introduced to join PE pipes, but most of these methods have many disadvantages such as costs, lack of reliability and difficulties in joining, etc. Recently butt welding has been paid much attention to joint PE pipes as this process has many advantages such as cost, safety and reliability. In this study, newly developed heat plate, a patent-pending heat plate with a groove, was used to butt-weld PE double wall pipes with different misalignment gaps to simulate real underground conditions, and the butt welding temperature of PE pipe was determined by thermal analysis (Thermal Gravimetric Analysis, Differential Scanning Calorimetry and Dynamic Mechanical Analysis). The resulting joining characteristics of double wall pipes were compared with those from a conventional heat plate, in terms of stiffness, flattening and leakage tests. The results from the stiffness and flattening test showed that there were no big differences between the butt-welded joints made from these two plates. From the leakage test, although PE pipes welded with a conventional heat plate did leak below the required test conditions (10 min. at 0.75kgf/cm2), the pipes welded with a patent-pending grooved heat plate did not show any leakage even at a pressure 1.5 times higher than the required conditions. It was noted that by utilizing a grooved heat plate more complete fusion at the pipe joints could be obtained, which in turn induced a high quality joints.