2 temperature instrumentation temperature instrumentation

For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 01/01/2006 rev 2 temperature instrumentation 2.3. thermowells 2.3.1. general information about thermowells 145 2.3.2. thermowell executions built up wells 1/2" x 1/2" BDTW11 152 1/2" x 3/4" BDTW12 152 1/2" x 1" BDTW13 152 bar stock stepped shank 1/2" x 1/2" BDTW31 152 1/2" x 3/4" BDTW32 152 1/2" x 1" BDTW33 152 bar stock tapered shank 1/2" x 1/2" BDTW51 152 1/2" x 3/4" BDTW52 152 1/2" x 1" BDTW53 152 bar stock straight shank 1/2" x 1/2" BDTW71 152 1/2" x 3/4" BDTW72 152 1/2" x 1" BDTW73 152 built...

For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 01/01/2006 rev 2 temperature instrumentation instrumentation index 2.1.1.

144 For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 01/01/2006 rev 2 2.3.1. temperature instrumentation thermowells

For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 145 01/01/2006 rev 2 thermowells Thermowells from Badotherm are precision components manufactured to the highest standards from barstock, forgings or fabricated material to serve as protection devices for primary sensing elements like bimetal thermometers, gasfilled thermometers, thermocouples and thermo elements. A wide range of possible products are available. Conditions of pressure, temperature and corrosion resistance governs the size, shape and selection of materials to ensure optimum dependability,...

146 important information instrument connection Instrument connections may be male or female with NPT, BSP or other threads. process connection Connection to the pipe or vessel may be done by means of thread, flange or weld. threaded connection Using standard tapered or parallel pipe threads for simplicity is popular, generally for low pressure applications. flanged connection All sizes and ratings are available to ANSI, DIN, BS, JIS standards. weld in connection Weld in thermowells are normally used where process pressure and velocities are too great for flanged and threaded executions, or where...

For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 147 01/01/2006 rev 2 flange and thermowell materials AISI 316 Best corrosion resistance of the austenitic stainless steel due to the addition of molybdenum, widely used in chemical processing, offers a useful resistance to H2S. As with AISI 304, a low carbon grade, AISI 316L is available for welded applications. Maximum temperature 900 °C. AISI 321 Similar properties to AISI 304, except that this grade is titanium stabilized to prevent intergranular corrosion. AISI 304 Low cost corrosion resistant...

148 flange and thermowell materials incoloy® 800 Superior to alloy 600 in sulphur, cyanide salts and neutral salts. Extensively used in steam/hydrocarbon reforming plants for pigtail piping, manifolds and waste heat boilers and in the internal components of secondary reformers. Widely used in heat treatment equipment and heater sheath material. Maximum temperature 1093 °C. monel 400 Nickel-copper alloy with very good corrosion resistance, commonly used to handle seawater, hydrofluoric acid, sulphuric acid, hydrochloric acid and most alkalis. Typical applications include marine fixtures, chemical...

149 thermowell strength calculation ASME/ANSI PTC 19.3-74 Thermowell performance test acc ASME/ANSI PTC 19.3-74 can be provided by Badotherm and implicates a typical calculation test for the wake frequency to the natural frequency of a thermowell (pressure and flow vibration). There are four parameters that are of paramount importance for the design of the thermowell. a) external pressure b) flow induced vibration c) material compatibility d) steady state bending stress The outcome of this test (to determine the wake frequency of a thermowell) must be less than 0.8, in instances where the ratio...

150 For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 01/01/2006 rev 2 2.3.1. temperature instrumentation Type W11 build-up (fabricated) thermowells To assist our clients in an immediate answer if a thermowell is suitable or not in the existing process, we enclose a number of graphs. The graphs show the maximum lengths possible for a given process velocity for a variety of popular thermowell designs. All graphs assume the well material to be AISI316, at an operating temperature of 20 °C. For different materials and process temperatures, a correction...

152 For technical data sheets and dimensional drawings please refer to our website www.badotherm.com 01/01/2006 rev 2 2.3.2. temperature instrumentation Badotherm thermowells are standard made out of stainless steel AISI316, but can also be manufactured in carbon steel , AISI304, AISI321, Duplex, Monel, Hastelloy C and others, see page 147 and 148. When ordering please specify all dimensions as mentioned here under accurately. d = inside diameter D= outside diameter G= taper end biggest diameter U= insertion length S = stem length instrument Type BDTW11 build-up (fabricated) straight shank, threaded...

153 2.3.2. temperature instrumentation Type BDTW81 build-up (fabricated) straight shank, flanged instrument connection 1/2”bsp / npt process connection ANSI / DIN / JIS flanges maximum 25 bar Type BDTW91 bar stock, stepped shank, flanged instrument connection 1/2”bsp / npt process connection ANSI / DIN / JIS flanges maximum 100 bar Type BDTW101 bar stock, tapered shank, flanged instrument connection 1/2”bsp / npt process connection ANSI / DIN / JIS flanges maximum 400 bar Type BDTW111 bar stock, straight shank, flanged instrument connection 1/2”bsp / npt process connection ANSI / DIN / JIS flanges...