Heat exchanger superfinishing. 4 Methodology of Heat Exchanger Performance Assessment 4. Heat exchanger superfinishing

 
4 Methodology of Heat Exchanger Performance Assessment 4Heat exchanger superfinishing  The water is propelled from a nozzle at an extremely high pressure up to 2500bar (36000psi), blowing away dirt and debris

This is achieved by removing just the thin amorphous surface layer left by the last process with an abrasive stone or tape; this layer is usually about 1 μm in magnitude. Sectors: Downstream, Midstream, Upstream. Superfinishing is an imprecise term for a range of manufacturing techniques that produce enhanced surface finishes. Powder & Bulk Processing. Often taken for granted in most race cars, the ring and pinion is often used, abused, with little attention paid until a failure occurs. Many scholars are also committed to studying its heat transfer. Selection of heat transfer models and fouling coefficients for shell side and tube side. The water is considered as hot fluid flowing in the tube, whereas air is cooling fluid in encloser volume or duct area. Unit 571 New Smyrna Beach, FL 32128 386-882-EZCE(3923) Vacmul EDM 3 has the correct balance of viscosity, volatility, oxidation stability, heat transfer characteristics, low odour and low toxicity. 325”) being typical. Transportation Alterations. Flat Plate and Fin Exchangers. The surface topography of a 600 grit. As implied by Figure 1 (b), the temperature difference ΔT = Th − Tc is approximately linear such that. Pada bentuknya terdapat fan atau kipas yang tentunya. storage type heat exchanger. A shell and tube heat exchanger passes fluids through and over tubes, where as an air cooled heat exchanger passes cool air through a. TEMA (Tubular Exchangers Manufacturing Association) is the preferred standard for the manufacture of shell and tube heat exchangers. Water to air heat exchangers transfer heat from a fluid (typically water) to the air, or vice versa. Locate the calibration data plot and equation for the propylene glycol flow meter. Transportation Alterations. Isotropic superfinishing has been demonstrated by many studies that it can have positive influence on friction/heat reduction and surface fatigue life improvement for sliding/rolling contact elements such as bearings and gears. Copper remains the preferred covering in continuous inkers due to its low ink and high heat. Now that you know where your furnace heat exchanger is and what it does, arrange for an annual furnace tune up. If it’s not done right, then you could have a cracked heat exchanger faster than normal. Air Cooling System of Heat Exchanger. Developed by REM Surface Engineering, ISF, or “Isotropic Superfinish”, is a polishing treatment for machined metal components that. It exchanges heat to the cooler fluid and in turn exits cooler than it entered. The heating period and cooling period constitute 1 (one) cycle. 1 No. docx), PDF File (. Shell-and-tube exchangers, as a tubular HEs, are generally built of a bundle of round tubes mounted in a cylindrical shell with the tube axis parallel to that of the shell. This exchange allows the cold air to increase and hot air to reduce temperature to make sure the air is properly warmed for the home. Many types of heat exchangers have been developed for use in steam power plants, chemical processing plants, building heat and air conditioning systems, transportation power. RAW MATERIAL Bars, tubes or sheets of steel (type 100Cr6 and other) are used as the raw material from which bearing rings are manufactured. Āvāz, Khuzestan, Iran. The heat exchanger is sized (plus safety margin) to remove the heat of the weight per hour. 2 percent, and alloying elements. Welded, semi-welded and brazed heat exchangers are used for heat exchange between high-pressure fluids or where a more compact product is required. Superfinishing is used for applications in which surface. Some of the more common Heat Exchanger Designs and types include: Tubular and Shell Heat Exchanger Design. 5” See pricing and included parts. PROKNIT series. Social media usage statistics. Introduction. For most continuous furnaces using cold oils, the initial load heats the oil to the operating temperature, and the heat exchangers remove the balance of the heat. October 5, 2023. Fouling has a significant impact on heat transfer across the heat exchanger surface, and therefore on the overall operational performance and the economics of the process. One of the tube sheets is. PDF. There are many different types of heat exchangers that are categorized based on different criteria, such as construction, flow arrangement, heat transfer mechanism, etc. The tests indicated that superfinishing offered no improvement in performance due to the high lubricant film thickness generated by the extremely high. Evaporators, condensers, and boilers are all different types of heat exchangers, which many people are unaware of. Camshaft induction heat-treated for wear and strength. Choose from our selection of heat exchangers, including over 350 products in a wide range of styles and sizes. If the part you require isn’t listed below, please contact our sales team on +44 121 359 5401, as a limited number of heat exchangers for certain obsolete British Leyland, Ford, Mercedes Benz and Perkins engines are available. Heat transfer is the science of how thermal energy is exchanged between different systems and substances. Seán Moran, in Process Plant Layout (Second Edition), 2017. 500L View Details. Heat flow through a furnace heat exchanger. Many people don’t know this, but condensers, boilers, and evaporators are also types of heat exchangers. When a heat exchanger cracks, it can get discolored from soot build-up. The second in a two-part series, this installment addresses induction gear hardening by encircling the whole gear or sprocket with an induction coil, also known as ‘spin hardening. Whereas in recuperators, where heat is transferred directly and immediately through a partition wall of some kind, from a hot to a cold fluid, both of which flow. Heat Exchanger Fundamentals Course# ME905 EZ-pdh. (a) Periodic heat transfer-conduction. A Heat Exchanger is a mechanical device that is used to exchange heat between fluids. Apr 2000, 122 (2): 388-393 (6 pages) Superfinishing is an abrasive finishing process in which a smooth work surface is produced by simultaneously loading a bonded abrasive stone against a rotating workpiece surface and oscillating (reciprocating) the stone. Heat always flows from hot to cold. Yeah, we know that’s crazy expensive. ’. This makes use of matrix which has high thermal capacity, through which hot and cold fluid pass alternatively. A shell and tube heat exchanger is a device where two working fluids exchange heat by thermal contact using tubes housed within a cylindrical shell. A general equation can be used to calculate the efficiency of heat exchanger developed for a number of known exchangers. These media may be a gas, liquid, or a combination of both. 2016a) which are between 100 and 1000 times lower than those of most metals used in heat exchangers. The. In the case of welding with a large contact area, the weld reinforcement (WR) becomes smaller, so the length of the molten pool decreases . A heat exchanger (also referred to as HX) is an espresso machine with a single boiler that is dedicated to steaming milk. com. Superfinishing removes 1-2 microns of stock on radius and requires less energy. removes the mechanism responsible for dissipating frictional heat from the contacting surfaces through bulk lubricant flow. Parallel flow - the hot fluid and the coolant flow in the same direction. Heat exchangers are also frequently referred to as non-linear, since there is a non-linear relationship between the flow on the primary side and the heat transferred. Central States Industrial (CSI) offers Alfa Laval's M Series plate heat exchangers as an efficient solution for general heating and cooling duties in hygienic applications. The most commonly used coolants are water, deionized water, disrupted glycol, and water solutions. Flexible - easy to adapt to changed duty requirements. A compromised heat exchanger can cause corrosion or damage to other furnace components, such as the draft inducer box or inducer motor. For this reason, Arrow has added the capability of Isotropic Superfinishing. Also, we can use these systems in a very wide range of temperature applications. In this post, we discuss how three types of heat exchangers work: plate and frame, shell and tube, and scraped surface. HEAT TREATMENTSubsequently, this Process Data Sheet of heat exchanger is given to mechanical engineer or the equipment fabricator to perform mechanical design of the equipment. Sludge or scale coating on surfaces reduces the heat exchanger’s thermal efficiency. For most applications, the austenitizing temperature is approximately 25-30°C above the A c3 temperature. With multiple heat exchangers, the cost is equivalent to hydroblasting on a per heat exchanger basis. AW189 input module view and heat distribution on the AW189 MGB (Gasparini et al 2014) In addition to the clever material choice, also very important is the design of thermal path inside the gearbox: allowing fast transfer of heat from sources to casing and housings (see Fig. APPLICATION & PERFORMANCE Suitable for the lubrication of high-speed spindles bearings, air line oilers, hydraulic systems requiring low-viscosity lubricants in grinders and other machine tools. Conclusions. Heat exchanger dapat digunakan untuk memanaskan fluida kerja pada suhu yang diperlukan. from the University of Waterloo (Canada) in 2012. However, these treatments are not material free and proper treatment process depends on the type. A heat exchanger typically involves two flowing fluids separated by a solid wall. hydraulic; multi-functional oils; gear oils & greases; slideway oils & greases; spindle oils & greases; chain oils & greases; greases & pastes; compressor oils. Heat exchangers are widely used in automobile radiators, domestic and. Superfinishing,. MSDS Data sheet difficult conditions of metals parts and assemblies. · Reduced transmission noise. If the heat exchanger is cracked or malfunctioning before you would typically expect it,. STANDARDS: • ISO TR 3498: L-FD and L-HM • ISO 6743-2: L. Choose from our selection of heat exchangers, including over 350 products in a wide range of styles and sizes. Heat exchangers are used in both cooling and heating processes. Flame Displacement. H. Salt has better heat-transfer properties and is often blended with small amounts of water if even higher heat transfer rates are required. Exhaust gases from the combustion process are released through the flue to the outside of the home. You will also find examples and applications of heat transfer in various industries and processes, such as heating, cooling, refrigeration. The process. Heat Exchangers. Date stamps and inserts Quick connectors and nipples Pressure plugs Sintered vents Heat transfer pipes. A zero surface area represents a system without a liquid-suction heat exchanger whereas a system having an infinite heat exchanger area corresponds to an effectiveness of unity. POLSTERREINIGER 12X0. Due to their dynamic design, heat exchangers can be personalized to adapt to any industrial process depending on many thermodynamic properties, such as the temperature,. The heat exchanger is used to heat a cold fluid from 120°F to 310°F. ). Shell and tube heat exchangers are, simply put, a device that puts two working fluids in thermal contact using tubes housed within an outer cylindrical shell. Abstract. A heat exchanger mixes cold air and heated air, enabling heat transfer so that the furnace attains equilibrium. (c) Solid storage medium is called matrix. J. Project engineers are responsible for determining the performance requirements and specifications. superfinishing gears using high density, non-abrasive ceramic media did in fact produce an isotropic micro-texture on the surface that facilitated lubrication. In a condenser, heated gas is cooled to the point of condensation, which transforms the gas or vapor into a liquid. A car radiator is a type of water to air heat exchanger, because its purpose is to get the heat out of the car engine. The tradeoff between cost and benefit is certainly an important. Heat exchangers are used in heating systems to separate two media, while at the same time transferring heat from one to the other. The cold fluid with capacity C c enters at t 1 and exits at t 2. Heat transfer is the science of how thermal energy is exchanged between different systems and substances. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions in a concentric tube (or double-pipe) construction. Heat Treatment of Gears is designed to provide the gear design engineer with a better understanding of heat treatment and its effects on gear quality and performance, especially as these considerations are critical to ensuring that the gears perform satisfactorily under anticipated service conditions. Heat treatment is a critical and complex element in the manufacturing of gears that greatly impacts how each will perform in transmitting power or carrying motion to other components in an assembly. Simply the austenitizing temperature T A was varied from 1000 °C to 1200 °C to set different grain sizes in the cuboidal samples with a size of 25 x 37 x 6 mm 3 while the austenitizing time was two hours in each case . Vacmul EDM 3 is a highly refined, narrow-cut, low viscosity fluid specially suited to finishing operations where a high quality finish is required. A179A179M-90a(2012) Standard Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser Tubes. These isotropic superfinishes achieve the highest performance ratings in terms of friction, heat, noise and wear in the bearing, gear, and turbine industries. Disebut juga sebagai Fin Fan Heat Exchanger yang memiliki perbedaan cukup banyak jika dibandingkan dengan jenis lainnya. [1] The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. Heat exchanger. These plates are positioned over each other to create a channel series so that fluid can move between them. 1. Heat. However, superfinished gears are still not widely used in automotive transmissions and axles. Heat damage in underground mines has always been a difficult problem that troubles mining work. In a gasketed plate heat exchanger, the plates are fitted with elastomeric gaskets which seal the channels and direct the fluids into alternate channels. Heat exchangers are devices that are used to transfer thermal energy from one fluid to another without mixing the two fluids. Heat exchangers last 15-18 years, so if your heat exchanger is aging, it may be time to replace. With the inverse heat transfer method, the heat flux to the workpiece surface is calculated form the measured temperature distribution within the workpiece. These media may be a gas, liquid, or a combination of both. The basic pieces and parts in a chiller (both air-cooled and water-cooled) are rather similar. Many of the heat transfer processes encountered in industry involve composite systems and even involve a combination of both conduction and convection. The thermal conductivity (k) and thickness (Δx) of the tube wall must also be accounted for. 1. Copper Heat Exchanger For Die Casting Machine, Compact. H. They consist of a shell with traditional plain tubes or enhanced surface tubes for high thermal performance. D. In another recent study of the optimization of the shell and tube heat exchanger, [2] proposed a method, motivated by constructed theory. Specific heat, or specific heat capacity, is a property related to internal energy that is very important in thermodynamics. Your heat exchanger supplier can get much. Mechanical: 1. The general principles of the mechanical design of the following types of exchangers are given in the Heat Exchanger Design Handbook (1994), and full descriptions of each, are given under the corresponding entries in this encyclopedia: Shell and Tube Exchangers. Heat exchanger duty, cold stream flow rate and mean temperature difference are also determined by the calculator. Image Credit: Anton Moskvitin/Shutterstock. This range of heat exchangers is used in the same hygienic applications as the BaseLine range, but the M Series is selected when higher design pressure or extra-long plate. The prototypical shell and tube heat exchanger has only one inner tube, and is typically used to teach engineering students the basic concept of a heat exchanger. This added cost will likely be negated by heat savings, as heating moist air requires a lot more energy than heating dry air. A plan for increasing heat exchanger performance for shell and tube exchangers should consider the following steps. The plate-and-frame or gasketed plate heat exchanger essentially. Additive manufacturing enables you to create next-generation heat exchanger designs to meet increasing product requirements. Heat exchangers. · Surface reduction to mirror like finishes. The general descriptions of the three major TEMA classes are: TEMA C – General Service. 2. A plate heat exchanger is a compact type of heat exchanger that uses a series of thin plates to transfer heat between two fluids. Teaching Assistant: • Technical Drawing Ⅰ. 1. On November 23, 2023, Alleima officially launched its state-of-the-art heat exchanger facility in its mill located in Mehsana, Gujarat. de) More than 21. 2. The fluids are. At the bottom of the column, the liquid is near its saturation condition. Jenis-jenis Heat Exchanger : 1. Mark R Riggs. Selection of heat exchanger TEMA layout and number of passes. Overall Heat Transfer Coefficient. The major challenges are the lack of generalised heat transfer and pressure drop correlations and design optimisation methodologies. 8(a) , the hot. 1 Extract from steam tables. Heat exchangers come in different types that have a. The media may be separated by a solid wall to prevent mixing or may be in direct contact. liquid to liquid. It is advantageous to apply various combinations of frequency, power density, and scan rates at various stages of the gear scan hardening cycle. In the parallel-flow arrangement of Figure 18. The general principles of the mechanical design of the following types of exchangers are given in the Heat Exchanger Design Handbook (1994), and full descriptions of each, are given under the corresponding entries in this encyclopedia: Shell and Tube Exchangers. This new facility will enable Alleima to produce advanced alloys in heat exchanger tubing locally to meet the increasing demand for the high valued added tubes to India’s chemical and petrochemical, renewable. Pemanasan. Líquidos de frenos. The furnace burns fossil fuels, hot gas heats the metal and the hot metal heats the air around it. Download as PDF. The furnace then brings in cool air from your home using the air return ducts. The investigation involves using the commercial code of ANSYS CFX, which incorporates the modeling,. In this work, a three-dimensional simulation has been carried out of a shell and tube heat exchanger (STHX) consisting of segmental baffles. October 5, 2023. REGENERATIVE HEAT EXCHANGERS. Both Buffing and Polishing Process is a common term and these are used in Manufacturing Processes or you can say manufacturing industry. from 0. · Reduced contact/surface fatigue. Heat exchanger jenis ini paling umum dan banyak digunakan. 4 Methodology of Heat Exchanger Performance Assessment 4. Plate-finned heat exchanger made by vacuum sol- The casting of components from high-duty cast iron greatly reduces the works' require- ments of rolling and forging divisions and also the number of rejects. Endothermic atmospheres are commonly used during the heat treatment of steel. Carbon provides the hardness, and the alloying elements provide. S. Heat exchanger prices depend on several factors, quality, size, energy efficiency, and whether it is a gas or electric furnace. The entire heat transfer process takes place in the large tube. Within the heat exchanger is a long, coiled pipe. This is defined by the heat flux density (W m −2). Carburizing can be performed in the temperature range of 800ºC (1475ºF) to 1090ºC (2000ºF). It is used to heat or cool a particular medium using another in the vicinity. Perhaps the most common cause for a ruptured heat exchanger is old age. Recent advances in technology have increased the use of energy recovery ventilators (ERVs) as well. Heat exchanger ini terdiri dari plate / lempengan yang ditumpuk berlapis - lapis. Because of its low heat generation it’s also suitable for dry machining. 18. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions. 1) The exchanger consists of a large outer shell (light gray) with tubes running through it (dark gray). 1 ratios for the transfer gears depending on the application. Condenser is used for cooling the object till the changing of phase from gaseous to liquid. Each tube passes through a series of baffles and tube sheets (also known as ‘ tube stacks ’). In the last two decades, a lot of research has been done to develop analytical and numerical models for the analysis of EAHE systems. Hot and cold fluids flow through this porous mass alternately. On the other hand, the lubrication prevents the heat development between the two moving surfaces. Also, over time, this will easily cause the heat exchanger to crack. Therefore, the. A shell-and-tube heat exchanger is a class of heat exchanger designs. parallel-flow. With a finned tubular heat exchanger, both fluids are unmixed, the one between the fins is guided in a. This double action is economically accomplished by a heat exchanger. This method requires the insertion of the tube. In heat transfer applications, nanofluids are utilized to increase thermal conductivity and heat transfer coefficient. 2. Different types of HVAC units are fitted with different types of heat exchangers. 4°F during the test. Siamak Farhad joined the Mechanical Engineering Department of The University of Akron in 2013. Heat exchanger dapat digunakan untuk memanaskan fluida kerja pada suhu yang diperlukan. A dehumidifier will cost between $200 and $300 to purchase, and maybe $10 to $15 a month to operate. Here, the company explains how it has become more effective using its multifunction lathe to produce small batches of custom racing camshafts. A heat exchanger is a heat transfer device that exchanges heat between two or more process fluids. Weddle S5 See pricing and included parts Weddle HV24 grinding & superfinishing; minimum quantity lubrication; soluble machining fluids; heat treatment; forming; cleaning & protection. 0 to 1. 8(a) , the hot and cold fluids enter at the same end, flow in the same direction, and leave at the same end. Other than the type and alloy composition of steels, the cleanliness of steels used for gears is of great. Is WSEAS a Predatory Publisher? No! Of Course, No!5. Sectors: Downstream, Midstream, Upstream. ( Learn more about myself and our team) I'm an avid home improvement professional with more. Alat penukar panas pipa rangkap terdiri dari dua pipa logam standart yang dikedua ujungnya dilas menjadi satu atau dihubungkan dengan kotak. Computational fluid dynamics (CFD) were used. Suitable for fluid. Surface Condenser Heat exchangers are devices that are used to transfer thermal energy from one fluid to another without mixing the two fluids. This is defined by the heat flux density (W m −2). Many of the heat transfer processes encountered in industry involve composite. Superfinishing is an imprecise term for a range of manufacturing techniques that produce enhanced surface finishes. Salt has better heat-transfer properties and is often blended with small amounts of water if even higher heat transfer rates are required. In Eq. · Reduced contact/surface fatigue. Tranter specializes in solving heat transfer problems in a variety of industries—from oil & gas to metals to pulp & paper. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions in a concentric tube (or double-pipe) construction. PDF. 2). Wait until the system cools before doing anything else to minimize exposure to hot fluids. How gasketed plate heat exchangers work. A heat exchanger is a device that allows the heat to be transferred from one fluid or medium to another. 3. Camshaft induction heat-treated for wear and strength. The tubes carry a fluid from their inlet to. A technological pro- cess of casting the following compressor components from high-duty castiron was introduced. In the case of a boiler, this means transferring heat from gas to the water that will be circulating around your home to the radiators and hot water tank. T1 T2 T1 T2 x The Simplest Heat Exchanger: Double‐Pipe Heat exchanger ‐counter current cold less cold less hot hot. · Reduced transmission noise. The number of fluids used for heat transfer operation maybe two or more. Cross Flow Spiral tubes Fig. Is my furnace nearing the end of its life (10+ years or more)? 2. It is sometimes referred to as the Stationary Header. Because of the U-shape, heat stress can be accounted for. valve and the heat transferred. Of particular interest are special tools with integrated metrology and automatic selection of defective parts. Pendinginan. 3. Hoses and accessories for thermoregulation. Does my furnace have trouble heating my home (are there hot and cold spots)? a) If you answered “no” to both,. Both contain a compressor, condenser, evaporator and an expansion valve. 42 . STANDARDS: ADVANTAGES • Zinc free. An air pumping device such as an axial flow fan or blower. The majority of air-to-air exchangers installed in northern climates are heat recovery ventilators (HRVs). 500L View Details. LIMITATION OF ABSTRACT . Here, more heat is extracted, resulting in the gases that are cooled to the point that they condense into water and. 7. This heat exchanger consists of two concentric pipes of different diameters. Two stages of heat transfer are used in these heat exchangers. Fatigue life as affected by manufacturing conditions. It must maintain an air-tight seal to prevent toxic gasses from entering your ducting system and into your home. Complete with transmission oil cooler mounting hardware and rock guard. Contact Supplier. Modern practice is to use air-cooled heat exchangers. h 1 = enthalpy in outside make-up air before the heat exchanger (kJ/kg, Btu/lb) h 2 = enthalpy in outside make-up air after the heat exchanger (kJ/kg , Btu/lb )Published on August 18, 2022. Badea Lepadatescu's 22 research works with 31 citations and 2,618 reads, including: Why the WSEAS is Not a Predatory Publisher. A plate heat exchanger is used to transfer heat energy from one fluid to another. 289. 700 - 2500. Siamak Farhad joined the Mechanical Engineering Department of The University of Akron in 2013. These isotropic superfinishes achieve the highest performance ratings in terms of friction, heat, noise and wear in the bearing, gear, and turbine industries. Vertical Turning Machine Modified with SUPFINA superfinishing device as a polishing machine. Key benefits of the isotropic surface finishing process. NUMBER OF PAGES . Table 2. While anybody can decrease or increase the temperature of a. The price of the unit alone is around $300 to $2,600 depending on the brand. A heat exchanger with U-tube packages takes up slightly. Old age. High pressure cleaning can reduce safety. HEAT EXCHANGERS Plate & Frame For Maximum Efficiency Optimum performance is a promise Tranter, tnc. Ms- Concrete Chipping for Mep Installations - Free download as Word Doc (. Heat exchangers are devices that transfer thermal energy from one fluid to another without mixing the two fluids. Fluid flows through the tubes while another fluid flows through the shell and the. Reduce friction and extend the life of your driveline components. Heat is first transferred from the hot fluid to the wall by convection, through the wall by conduction,. Because of plate and frame exchangers’ smaller, modular design, they are faster and easier to clean than larger shell-and-tube units. On the other hand, about u tube heat exchanger advantages we need to say that the benefits stem from its compact size, which is also very powerful. The wrong material can lead to higher cost and longer production times if it’s more difficult to. //Shell & Coil. 2. Mass produced stock gears can crack and fail when subjected to extreme conditions. The 1. 2 kg/s. Condensers are heat exchange devices that take hot gas and cool it to the point of condensation, turning the gas or vapor into a liquid. This procedure is as simple as watching the flame and observing if the flame moves or. The wear and tear of years on your furnace will naturally lead to cracks over time. pdf. 1. Storage type: Also called as fixed matrix or fixed bed regenerator this is a periodic flow heat transfer device. D. Contact Mechanics of Superfinishing. The fluids can be separated or in direct contact according to the type of. TOPICS. You may also notice soot building up within the furnace, which indicates the burner is not functioning properly. Know more . The combination of heat generation without the ability to dissipate the heat leads to a thermal runaway in the mechanical component. 1 General. Tube Tech guarantees to remove 90%+ fouling from the shell and tube side of heat exchangers. The internal cleaning of heat exchangers under high pressure is carried out with flexible hoses or with stainless steel lances. Assuming that the hot fluid enters at 500°F and leaves at 400°F, calculate the LMTD for the exchanger.