The Effect of Air Knife Flow Rate on Coating Weight and Thickness for a Hot Dipping Process Simulator

2014 ◽  
Vol 633-634 ◽  
pp. 180-183
Author(s):  
Fang Fang ◽  
Li Xin Wang ◽  
Shao Yun Zhou ◽  
Jiang Wen Li
Keyword(s):  
Surface Quality ◽  
Flow Rate ◽  
Coating Thickness ◽  
Dew Point ◽  
Zinc Bath ◽  
Key Factor ◽  
Dipping Process ◽  
Coating Weight ◽  
Process Simulator ◽  
Air Knife

A series of air knife flow rate were conducted by a hot dipping process simulator in laboratory to study its effect on coating weight and thickness. The research results show that, when the experimental steel were immersed for 3.5s in a Zn-0.24%Al zinc bath, with atmosphere of N2-10%H2 and dew point-60°C in the whole simulation, air knife flow rate (FR) was a key factor for coating surface quality. When FR was precisely controlled by the simulator from 200~500 l/min, the coating weight and thickness decreased significantly from 159.68 to 56.19 g/m2 and 17.45 to 7.84 μm. In which the decreasing line was more obvious when FR increased from 300 to 400 l/min, that the coating thickness had a dramatic decreasing from 18.08 to 11.07μm.

Parametric study on pressure-based packed bed adsorption system for air dehumidification

2021 ◽  
pp. 095440892110073
Author(s):  
V Sureshkannan ◽  
TV Arjunan ◽  
D Seenivasan ◽  
SP Anbuudayasankar ◽  
M Arulraj
Keyword(s):  
Genetic Algorithm ◽  
Taguchi Method ◽  
Flow Rate ◽  
Uptake Rate ◽  
Air Flow ◽  
Packed Bed ◽  
Air Pressure ◽  
Dew Point ◽  
Adsorption System ◽  
Air Flow Rate

Compressed air free from traces of water vapour is vital in many applications in an industrial sector. This study focuses on parametric optimization of a pressure-based packed bed adsorption system for air dehumidification through the Taguchi method and Genetic Algorithm. The effect of operational parameters, namely absolute feed air pressure, feed air linear velocity, and purge air flow rate percent on adsorption uptake rate of molecular sieve 13X-water pair, are studied based on L25 orthogonal array. From the analysis of variance, it has been found that absolute feed air pressure and purge air flow rate percent were the parameters making significant improvement in the adsorption uptake rate. A correlation representing the process was developed using regression analysis. The optimum adsorption conditions were obtained through the Taguchi method and genetic algorithm and verified through the confirmation experiments. This system can be recommended for the industrial and domestic applications that require product air with the dew point temperature below 0°C.

scholarly journals PENGGUNAAN STEEL GRIT G25 PADA SANDBLASTING BAJA KARBON RENDAH JIS-G3101-SS400

2019 ◽  
Vol 17 (3) ◽  
Author(s):  
Muslimin Muslimin ◽  
Azam Milah Muhamad
Keyword(s):  
Surface Quality ◽  
Coating Thickness ◽  
Construction Material ◽  
Low Carbon Steel ◽  
Process Time ◽  
Material Surface ◽  
Low Carbon ◽  
Abrasive Material ◽  
Abrasive Particles ◽  
Fixed Parameter

ABSTRACTSandblasting is an abrasive particles shooting to material surface for cleaning dust, paint, and rust, along as increasing material surface structure quality for coating, painting and other adhesive process. Al2O3 and steel grit are the most abrasive particles used in this process. Al2O3 is reusable particle inspite of more expensive and producing more dust. On the other hand, steel grit is cheaper and producing less dust. This article focuses on the use of the new and the reused steel grit G25 in sandblasting process of construction material low carbon steel. The objective is to study the effect of the new and reused abrasive material steel grit in sandblasting process on the surface quality. The methods of this experiments are comparing the surface quality of sandblasting process of new and once reused steel grit G25 using the same experimental parameters. Fixed parameter in this experiment is the nozzle pressure, 5 bar, while the independent variables are process distance (15 cm, 25 cm, and 30 cm) and the process time (25 s, 45 s, 120 s). Testing analyses in this experiments are roughness test ASTM D7127-13 and coating thickness test ASTM D-7091. Result of the experiment are coating thickness result are the highest 120 μm and the least 94,14 μm for the new steel grit, while 89,88 μm and 58,58 μm the highest and least for the once used steel grit. Highest roughness result for the new steel grit are 21,4 μm and once used steel grit 17,8 μm, while the least rough are 18,1 μm for the new steel grit and 3, 452 μm for once used steel grit. The once used steel grit G25 still can be accepted as abrasive material in sandblasting process but with less good quality than the new one.Key words :sandblasting, new steel grit G25, new steel grit G25, surface roughness.ABSTRAKSandblasting adalah suatu proses penembakan partikel abrasif ke suatu permukaan untuk membersihkan debu, cat, dan karat, dan membuat tekstur permukaan material agar lapisan pelindung dapat menempel lebih baik. Partikel abrasif yang banyak digunakan dalam proses sandblasting adalah Al2O3 dan steel grit. Partikel Al2O3 memiliki ketahanan abrasive yang tinggi, tetapi harganya lebih mahal dan menghasilkan debu proses lebih banyak. Sedangkan, steel grit harganya lebih murah dan sedikit menghasilkan debu proses. Penelitian ini berfokus pada penggunaan material abrasif steel grit G25 baru dan pemakaian ulang untuk proses sandblasting baja karbon rendah untuk material konstruksi. Tujuan penelitian ini adalah mengkaji pengaruh penggunaan steel grit G25 dan penggunaan ulangnya terhadap kualitas permukaan hasil sandblasting.Metode yang digunakan, yaitu dengan membandingkan hasil proses sandblasting dengan partikel steel grit G25 baru dan partikel steel grit G25 pemakaian ulang (1 kali pemakaian) dalam parameter uji yang sama. Parameter tetap yang digunakan yaitu tekanan nozzle sebesar 5 bar, sedangkan variabel bebasnya yaitu jarak (15 cm, 25 cm, dan 30 cm) dan waktu penembakkan (25 detik, 45 detik, dan 120 detik). Analisis pengujian yang digunakan adalah uji kekasaran ASTM D7127-13 dan uji ketebalan cat ASTM D7091. Nilai ketebalan cat tertinggi steel grit baru 120 μm, steel grit ulang 89,88 μm, dan terendah steel grit baru 94,14 μm, steel grit ulang 58,58 μm. Nilai kekasaran tertinggi steel grit baru 21,4 μm, steel grit ulang 17,8 μm, dan terendah steel grit baru 18,1 μm, steel grit ulang 3,452 μm. Penggunaan steel grit G25 penggunaan baru lebih baik dibandingkan dengan penggunaan ulangnya, dengan hasil pengujian steel grit baru yang lebih tinggi dengan penggunaan ulang.Katakunsi : sandblasting, steel grit G25 baru, Steel grit G25 sekali pakai, kekasaran permukaan.

scholarly journals Relationship between Oxygen Defects and Properties of Scandium Oxide Films Prepared by Ion-Beam Sputtering

Coatings ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 517
Author(s):  
Pengfei Kong ◽  
Yunti Pu ◽  
Ping Ma ◽  
Jiliang Zhu
Keyword(s):  
Refractive Index ◽  
Surface Quality ◽  
Flow Rate ◽  
Ion Beam ◽  
Oxygen Flow Rate ◽  
Scandium Oxide ◽  
Oxygen Flow ◽  
Ion Beam Sputtering ◽  
Oxygen Defects ◽  
Beam Sputtering

Scandium oxide (Sc2O3) thin films with different numbers of oxygen defects were prepared by ion-beam sputtering under different oxygen flow rates. The results showed that the oxygen defects heavily affected crystal phases, optical properties, laser-induced damage threshold (LIDT) and surface quality of Sc2O3 films. The thin film under 0 standard-state cubic centimeter per minute (sccm) oxygen flow rate had the largest number of oxygen defects, which resulted in the lowest transmittance, LIDT and the worst surface quality. In addition, the refractive index of 0 sccm Sc2O3 film could not be measured in the same way. When the oxygen flow rate was 15 sccm, the Sc2O3 film possessed the best transmittance, refractive index, LIDT and surface roughness due to the lowest number of oxygen defects. This work elucidated the relationship between oxygen defects and properties of Sc2O3 films. Controlling oxygen flow rate was an important step of limiting the number of oxygen defects, which is of great significance for industrial production.

scholarly journals Application of Supergravity Technology in a TEG Dehydration Process for Offshore Platforms

Processes ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 43 ◽  
Author(s):  
Hongfang Lu ◽  
Guoguang Ma ◽  
Mohammadamin Azimi ◽  
Lingdi Fu
Keyword(s):  
Natural Gas ◽  
Flow Rate ◽  
Packed Bed ◽  
Gas Production ◽  
Dew Point ◽  
Transfer Model ◽  
Offshore Platforms ◽  
Dehydration Process ◽  
Tower Equipment ◽  
Rotating Packed Bed

In the dehydration process of offshore natural gas production, due to the site limitation of the platform, if the conventional triethylene glycol (TEG) dehydration process is employed, the size of the absorption tower is usually small. However, in the case of fluctuations in raw material gas and large gas production, it is easy to cause a large loss of TEG and a flooding event, resulting in the water dew point of natural gas not meeting the requirements. Therefore, combined with the dehydration process of TEG and supergravity technology, a new dehydration process of natural gas suitable for offshore platforms is proposed in this paper. The principle and process of the TEG dehydration process based on supergravity technology are discussed by establishing a mass transfer model. The laboratory experiment of the new process is carried out, and the effects of TEG flow rate, super-gravity packed bed rotation speed, and gas flow rate on the air dew point are obtained. By studying the dewatering balance of the rotating packed bed in the improved process, it is proved that the dewatering performance of the high gravity machine (Higee) is much better than that of the ordinary tower dewatering equipment. Through field experiments, the dewatering effect of continuous operation and sudden changes in working conditions is obtained, indicating that the Higee can completely replace the traditional tower equipment for natural gas dehydration.

scholarly journals Siltation and Desilting Practices in A Runoff Reservoir on Heavy Sediment-Laden River

2018 ◽  
Vol 246 ◽  
pp. 01062
Author(s):  
Dangwei Wang ◽  
Anjun Deng ◽  
Zuwen Ji ◽  
Hongling Shi
Keyword(s):  
Flow Rate ◽  
Sediment Concentration ◽  
Reservoir Capacity ◽  
Power Station ◽  
Flood Season ◽  
Medium Flow ◽  
Key Factor ◽  
Diversion Channel ◽  
Dam Site ◽  
Sediment Deposit

Sediment deposition in the reservoir of run-of-the-river power station is severe, in this paper we take upper Marsyangdi reservoir as an example to analyze sedimentation and desilting process according field data measured from September 2016 when the reservoir had just been impounded in order to find strategy for managing reservoir sedimentation. The ratio of Upper Marsyangdi reservoir capacity and volume of sediment into the reservoir is about 0.2. The reservoir arrived silt-stable in a year after impoundment with a depth of 12m deposition at the dam site. Most of sediment deposit in the periods that at the initial and the end of flood reason and it is found the flow rate is the key factor influencing trap efficiency because that due to damming velocity of medium flow decreased significantly compared to natural condition which caused numerous deposition. Based on result of analysis of deposition the desilting condition is determined. Empty flushing is proposed to release deposition after flood season when flow rate is greater than 100m3/s and the new capacity will last to next flood season. In order to reduce sediment concentration into diversion channel a desilting should be done in flood season when flow rate is larger than 200m3/s and flow rate for impound should not be more than 1/10 of that into reservoir which can avoid deposition during impoundment near dam site.

ANALYSIS AND MICROHARDNESS PROFILE OF HOT DIPPING COATING ON LOW-ALLOY STEEL

2020 ◽  
pp. 2050059
Author(s):  
ABEER SHEHAB ◽  
ATHIL AL-EZZI ◽  
ALI AL KATAWY
Keyword(s):  
Alloy Steel ◽  
Steel Surface ◽  
Zinc Coating ◽  
Hardness Profile ◽  
Low Alloy Steel ◽  
Zinc Bath ◽  
Pure Zinc ◽  
Microhardness Profile ◽  
Steel Aisi ◽  
Dipping Process

This research is an effort to understand the morphology of the coating produced during hot dipping process in pure zinc bath based on iron–zinc phase diagram. In this investigation, zinc coating on low-alloy steel AISI 4340 samples was applied by hot dipping method followed by an annealing process. Morphological characterizations of the steel surface layer were accomplished by optical microscopy (OM) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectrometry (EDS). Results revealed that the coating is bonded to the steel surface through a sequence of Fe–Zn layers namely alpha ([Formula: see text], delta ([Formula: see text] and zeta ([Formula: see text] with uniform sloping hardness profile.

scholarly journals Sensorization of Shot Peening for Process Monitoring: Media Flow Rate Control for Surface Quality

Procedia CIRP ◽  
2020 ◽  
Vol 87 ◽  
pp. 397-402
Author(s):  
Augustine Teo ◽  
Jin Yicheng ◽  
Kunal Ahluwalia ◽  
Ampara Aramcharoen
Keyword(s):  
Surface Quality ◽  
Process Monitoring ◽  
Flow Rate ◽  
Rate Control ◽  
Shot Peening ◽  
Flow Rate Control

Meteorological Factors Affected Dew Condensation in Marsh Ecosystem

2014 ◽  
Vol 535 ◽  
pp. 360-363 ◽  
Author(s):  
Ying Ying Xu ◽  
Bai Xing Yan ◽  
Hui Zhu
Keyword(s):  
Meteorological Factors ◽  
Meteorological Condition ◽  
Sanjiang Plain ◽  
Dew Point ◽  
Nutrient Cycle ◽  
The Sanjiang Plain ◽  
Dew Formation ◽  
Key Factor ◽  
The Relationship ◽  
Dew Amount

Dew is one of crucial factors in the water and nutrient cycle in wetland ecosystem, especially playing an important role in the water and nutrients balance. Identifying the meteorological factors which affect the formation of dew is necessary. The meteorological condition is the key factor of dew condensing; therefore, it is necessary to identify the relationship between meteorological factors and dew formation. Dew amount was monitored and collected in the Sanjiang Plain. The highest mean dew amounts at Sanjiang Plain were observed in Craex lasiocarpa community (0.130mm night-1). Nearly 50% dew events correspond to the smallest yields (<0.04 mm="" night="" sup="">-1) and it is implies there are around half days are unsuitable for dew condensation in Craex lasiocarpa community. Our study impies that dew data, taken in growthing season of 2003 to 2005 and 2008, correlated positive with relative humidity, dew point temperature, and vapour pressure.

Effect of Coating Thickness on the Friction Coefficients and Torque-Tension Relationship in Threaded Fasteners

2008 ◽  
Author(s):  
Amro M. Zaki ◽  
Sayed A. Nassar
Keyword(s):  
Test Data ◽  
Coating Thickness ◽  
Time Data ◽  
Friction Coefficients ◽  
Threaded Fasteners ◽  
Highly Sensitive ◽  
Structural Applications ◽  
Key Factor ◽  
Set Up ◽  
Bearing Friction

This paper experimentally investigates the effect of coating thickness on the thread, bearing friction coefficients and torque-tension relationship in threaded fasteners. The torque-tension relationship is highly sensitive frictional changes. Two different coating thicknesses are investigated using two bolt sizes; realtime test data is collected for two ranges of bolt tension. The experimental set up collects real-time data on the tightening torque, bolt tension, and the corresponding reaction torque. Test data is used for calculating the thread and bearing friction coefficients, as well as the overall torque-tension relationship for two different coating thicknesses. The study would provide an insight into the variation of the torque-tension relationship which is a key factor that significantly affect the reliability and safety of bolted assemblies in many mechanical and structural applications.

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