This paper presents a method of plane development for shiphull plate with bspline surface representation, and provides the shrinkage heating lines in the forming process. The forming of hull plate by line heating method has been largely dependent upon the skills of experienced workers. However, in the actual line heating process in shipyard, the rapid quenching. When applying automated equipment, it is necessary to. A preliminary study on the angular distortion by lineheating. When heating, it is important to size the system as close to the heat loss calculation as possible to prevent 1 drafts, 2 hot and cold spots, and 3 short cycling of equipment. When you design a heating or air conditioning system you need to know how cold or hot it is likely to get in your area this is the outdoor design temperature and what.
The method of lines refers to an approximation of one or more partial dif ferential equations with ordinary di. The part of a furnace that transfers heat to nearby air. Preheating method of lithiumion batteries in an electric. Electric heating is free from flue gases hence no need of exhaust system for heat generation. Branches are connected to the submains and they are along the streets. The authors carried out the preliminary experiments on the effects of line heating for the efficient method of platebending. Assuming additionally the supply line voltages symmetry and load symmetry, the task is limited to making calculations only for a single heating element generating power p3. It requires only a diameter tally of pieces intersected by a sample line, and application of a simple formula. On the material properties of shell plate formed by line. C, heating and chargedischarge experiments have been performed on the battery pack. There are many reasons not to wait until july to buy a new air conditioning unit or december to purchase a new furnace. This article compares two industrial heating methods.
Develop a complete line heating system that can be used by shipyards to efficiently and accurately form complex shapes in typical plate sections. This is the whole forming process by pure line heating. The line heating method is a popular technique used in shipyards to form ship hull pieces. Rlf are presented in the residential heating and cooling loads calculation chapter of the 2005 ashrae handbook fundamentals ashrae 2005.
Acquisition of line heating information for automatic. Then transport the bag as rapidly as possible to the analytical area while maintaining the heating, or cover the box with an insulating blanket. The tlm formulation is based on a resistance and capacitance network and allows for temperaturedependent and inhomogeneous material parameters, nonuniform mesh, and variable timestepping. Line intersect method in forest fuel sampling forest. Acquisition of line heating information for automatic plate. No more frozen drain pipe at home, cottage, cabin, farm with heat line pipe warmer trace heating solutions. In a heat pump system, the evaporator coil is not referred to as a heat exchanger. Interconnect joule heating under transient currents banafsheh.
Use subcooling as the primary method for final system charging of long line set system application. On the material properties of shell plate formed by line heating core. This method of heating is employed in salt bath furnace. Development of the residential load factor method for heating and cooling load calculations charles s. Note for the formula below, the linear feet of line set is the actual length of liquid line or suction line, since both should be equal used, not the equivalent length calculated for. Prediction of steel plate deformation due to triangle heating using the inherent strain method chang doo jang1, tae hoon kim2, dae eun ko3, thomas lamb4, and yun sok ha5 1 department of naval architecture and ocean engineering, seoul national university, san 561, sillim dong, kwanakgu, seoul 151744, korea 2 lg eds, korea 3 samsung heavy. Top of mind should be how effective that heating method is at reaching your product goals. Prediction of steel plate deformation due to triangle. There are two types of change that are driven by process heating. Process heating 6 process heating in industry types of process heating process heating is a diverse area and this section lists some of the more common process heating techniques and the sectors in which they are frequently used.
Industrial heating methods, convection or infrared. Gas line sizing we now know the kind of piping which can be used for the distribution of natural gas within a building and the rules for installation. A heating pad that alleviates the symptoms of shoulder stiffness, backache,muscular fatigue, cramps, excessive sensitivity to cold, etc. Now we will learn how to size the pipe running to each appliance so that the proper amount of gas can be delivered to each piece of equipment, including adjustments required due to elevation. This paper is concerned with investigating the plastic material properties of steel plate formed by line heating method, and is aimed at implementing more. Solar water heating for businesses pacific gas and. Add charge to lower superheat or recover charge to raise superheat. A ton of cooling load is actually 12,000 btu per hour heat extraction equipment. Hydronic heating systems have the potential to deliver a precise rate of heating when and where its needed within a building. This paper presents a shiphull plate forming way by pure line heating.
Heatline freeze protection systems inpipe heating cables. Method and apparatus for providing reliable blood oxygen sa02 and heart rate measurements includes a chemical energy heating source in conjunction with a harness that is adapted to secure the chemical energy heating source and a pulse oximeter probe proximate to a region of the body which is to be warmed prior to measurement. Ensure the thermometer makes adequate contact and is insulated. No more frozen drain pipe at home, cottage, cabin, farm with heatline pipe warmer trace heating solutions. Manufacturing and production restaurant and food service heating and cooling buildings industrial processing heat laundering dishwashing and sanitization heating swimming pools.
It requires only a diameter tally of pieces intersected by a sample line, and applica. The dynamic mesh refining method developed by the authors was extended to simulate large scale plate forming process by line heating. The purpose of residential ductwork design is to properly distribute the airflow, produced by your heatingcooling system, to your house. Longduration soil heating resulting from forest floor duff smoldering in longleaf pine. In principle, the loads are calculated to maintain the indoor design conditions. At present a practical method to accurately predict the deformation of a plate formed by line heating does not exist. To improve the lowtemperature chargedischarge performance of lithiumion battery, low temperature experiments of the chargedischarge characteristics of 35 ah highpower lithiumion batteries have been conducted, and the wideline metal film method for heating batteries is presented. To correct distortion in larger complex fabrications it may be necessary to heat whole areas in. Pdf laser line heating is a plate bending technique.
A method for estimating wood volume on the ground is described. All information provided in this document is to be used as a guideline only. On the material properties of shell plate formed by line heating. In the analytical area, keep the box heated to 120 c 5 c until analysis. Acquisition of line heating information for automatic plate forming chang doo jang 1, sung choon moon 2 and dae eun ko 3 currently, the promotion of productivity is a significant topic in shipbuilding. Heating pad and method of using the same patent europe pmc. The key word in the previous sentence is potential. First we discuss the basic concepts, then in part ii, we follow on with an example implementation. Line heating is the term given to a method of bend processing of a steel plate to produce threedimen sional curvature from a flat plate by alternating heat.
The heating lines forming the required bending angle is determined by curvature analysis method. Using hot taps for in service pipeline connections contd addition, removing a pipeline segment from service can occasionally cause gas service interruptions to customers. Wo2081956a1 method and pulse oximeter apparatus using. Because of the recent trend toward the decrease in the number of skilled workers, it has become necessary to mechanize the line heating operation and establish the forming technolgy. In order to obtain sufficient information in deriving the formulae of predicting deformation due to line heating, line heating test have been conducted with single and multitorch with varying plate thickness, heating speed and distance between torches, d torch such that heat input parameter, q defined as eq. Heat line has your solution for reliable water pipe freeze protection or roof and gutter heat tracing and more applications such as frozen sewer pipes.
Schematic of steadystate methods commonly used for measuring the thermal conductivity of bulk materials. The method of lines mol is a general procedure for the solution of time dependent partial differential equations pdes. Near peak heating, 1% to 5% of the total thermal energy is transferred to the entry system example. Supply of heat to the flow is an effective method to solve these problems, and the direct electrical heating deh method has been developed and qualified for heating of pipelines.
Measurement techniques for thermal conductivity and. The term ton comes from the amount of cooling provided by two thousand pounds or one ton of ice. Thermomechanical analysis of line heating process by an. The purpose of this study is to find a relation between several heating conditions and induced angular distortions. Written by one of the foremost researchers in the tlm method, this book covers the entire area of electromagnetics from the basic principles to advanced formulations and applications and including microwaves, antennas, rcs, electromagnetic compatibility, and electromagnetic heating, while providing a clear explanation of modeling principles. The inherent strain method is known to be very efficient in predicting the deformation of steel plate by line heating. Design of convex hull plate forming by pure line heating. Thegoalofthiscourseistoprovideaccurateandusefuli nformation. The following are the 2 methods employed in resistance heating.
Investigations of technique parameter prediction method of line heating based on. Even recently, skilled workers have performed the forming process by their empirical intuition and so no systematic way to effective formation has been found. Utilisation of electrical energy electrical heating g. Because of the recent trend toward the decrease in the number of skilled workers, it has become necessary to mechanize the line heating operation and establish the forming. Todays hotwire method instruments allow more than data. In order to obtain sufficient information in deriving the formulae of predicting deformation due to line heating, line heating test have been conducted with single and multitorch with varying plate thickness, heating speed and distance between torches, d torch such that heat input parameter, q. The sample is placed between a heat source and a heat sink, with. Lastly service connections are given to the consumers from branches. The purpose of residential ductwork design is to properly distribute the airflow, produced by your heating cooling system, to your house. Resistance heating according to the joules law the resistance loss i2rt is used to producing the heat from electrical energy for various industrial purposes like welding, heating of buildings etc. To correct distortion in larger complex fabrications it may be necessary to heat whole areas in addition to employing line heating. Air conditioner, alternative methods of heating, energy efficiency, hvac, related products august 31, 2009 admin. Most air conditioning and heating systems require some form of duct work to channel or direct the air to places where the conditioned air is needed.
The component is heated along the line of the welded joint but on the opposite side to the weld so the induced stresses will pull the flange flat. According to the joules law the resistance loss i2rt is used to producing the heat from electrical energy for various industrial purposes like welding, heating of buildings etc. While it is always important to consider the cost and time requirements or a new heating system. Parameters of kanthal a1 round wires are given in fig. A heat pump is a specialized type of condenser which functions in both cooling and heating your home. In the present study, we investigate transient heating effects using the transmission line matrix tlm method 10,11. A complete electric heat tracing system will typically include the following components1. The shade line factor slf is the ratio of the distance a shadow falls beneath the. Interconnect joule heating under transient currents. A study on the thermal deformation characteristics of steel plates. Understanding basic residential ductwork design please note. Influential factors affecting inherent deformation. Mar 28, 2009 near peak heating, 1% to 5% of the total thermal energy is transferred to the entry system example.
This method is used in ordinary domestic radiator, the. When a furnace is grossly oversized, the unit will constantly cut off and on. Without proper design, and proper balancing, that potential seldom becomes reality. Be sure that the method of heating the box and the control for the heating. Identification of the heat equation parameters for estimation. Refer to the superheat table provided for proper system superheat. Heat exchangers are present in all furnaces regardless of the heating method used. Report documentation page defense technical information.
The line intersect method in forest fuel sampling, forest science, volume 14, issue 1, march 1968. It may satisfy the thermostat but leave other parts of the home either over or under. An electric heating system is economical compared to other conventional heating systems. Pdf developed inherent strain method considering phase. For best results, temporarily install a thermometer on the suction line near the compressor. For example, a shutdown connection on a steel line can require one to three or more days of pipeline outage and possible interruption of natural gas shipments in addition. Prediction of steel plate deformation due to triangle heating. A study on the thermal deformation characteristics of steel. Electric heating is free from dirt hence minimum effort for cleaning is required. Theory for the formula is presented, and practical application discussed. The authors carried out the preliminary experiments on the effects of lineheating for the efficient method of platebending. The present study aims to reduce the tremendous computation time in transient thermalmechanical analysis of line heating with a moving heat source. This paper is concerned with investigating the plastic material properties of steel plate formed by line heating method, and is aimed at implementing more rational design considering the accidental limit states such as collision or grounding. By investigating the results of line heating test and numerical analysis.
Most air conditioning and heating systems require some form of duct work. A guide to manual j 7th or 8th edition the following discussion is for manual j8 users manual j8 was developed to provide two methods of calculating residential loads. This method implies reduced investments of depressurizing systems. Submains are connected to the main line and they are along the main roads. Pdf effect of operating parameters on plate bending by laser line. The thermometer should be located within 4 to 6 of the compressor.
Induction heating equipment has become commonly used in automatic line heating. A study on the thermal deformation characteristics of. In the context of hydronics, balancing refers to the. Electric heat tracing cable2 selfregulating, power limiting, parallel constant watt or series constant watt.
Flame straightening using the heat line method takes place on the opposite side of the fillet weld at those points at which the flange needs to be shortened. There is no water distribution to consumers from trunk line. An optional, less accurate, method is to locate the thermometer at the suction line service valve. Testing and troubleshooting trace heating cable testing selfregulating cable a test should be performed when the heating cable is received, prior to installation and after installation using a 500 vdc megger. To calculate the amount of extra refrigerant in ounces needed for a line set over 15 feet, multiply the additional length of line set by 0. Note for the formula below, the linear feet of line set is the actual length of liquid line or suction line, since both should be equal used, not the equivalent length calculated for the suction line. Line heating isthe work method specifically developed to productively achieve the. Heatline has your solution for reliable water pipe freeze protection or roof and gutter heat tracing and more applications such as frozen sewer pipes. The reason these shipyards are not using their heavy machines is because line heating is usually quicker and more accurate than methods using heavy machinery.
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