Typical Liner Material Properties Mechanical Properties ASTM Unit PVC CPVC PP PVDF PVDF AS ECTFE ETFE FEP PFA RTRP Typical Specific Gravity1 D792 See Note 2 1.32 1.55 .91 1.76 1.78 1.69 1.70 2.15 2.15 1.12 Tensile Strength1 D638 psi (SI) 6300 (45) 8000 (55) 5000 (33) 7111 (50) 4900 (32) 6400 (45) 6250 (44) 3400 (25) 3840 (27) 18000 Tensile Modulus1 D638 psi (SI) 360000 (2500) 360000 (2500) 170700 (1200) 341400 (2400) 250000 (1750) 241800 (1700) 156500 (1100) 60500 (425) 39800 (280) 1550000 Flexural Modulus1 D790 psi (SI) 415000 (2860) 415000 (2860) 200000 (1406) 320000 (2250) 241800 (1700) 241800 (1700) 184900 (1300) 98900 (660) 98900 (660) 1150000 Flexural Strength1 D790 psi (SI) 15100 (104) 15100 (104) 6685 (47) 10525 (74) 6381 (44) 6258 (44) 5500 (39) 2560 (18) 2560 (18) 23000 Hardness D2240 Shore D 80 80 73 77 77 75 67 56 60   Elongation at break1   % 20-30 20-30 20-300 20-80 15 200 200 299 300   Thermal Properties                         Maximum Service Temp.   ** 140 / 60 190 / 90 200 / 94 300 / 149 250 / 120 300 / 149 300 / 149 400 / 205 500 / 260 300 Linear Thermal Exp. Coef.3 D696 Fo 35 35 85 70 80 40 75 50 70 18 Heat Melt Point   Fo 220 230 330 342 315 465 515 525 590 N/A Distortion Temp. D648 @ 264 psi   135 180 107 235 150 170 270 118 118 200-280 Fire Class UL 94   V-O V-O HB/V-2 V-O V-O V-O V-O V-O V-O

	Note 1: Tests were run at ambient temperatures, and the manufacturers supplied the results. Note 2: PSI = Pounds per square inch, SI = N/mm2 : Newton per square millimeter. Note 3: Thermal expansion 10-6 in/(in x oF change)
	Typical Liner Material Properties 2.4.3 Bonding Laminate The bonding laminate with a conductive element for spark testing will consist of one the following: A. 1- layer of conductive veil, followed by 2- layers of 1 1/2 oz. chopped strand mat, utilizing the same resin of construction. B. The weld seams covered with a graphite loaded resin putty, no more than 1" wide, followed by 2- layers of 1 1/2 oz. chopped strand mat, utilizing the same resin of construction. The layers of mat must be applied prior to the putty going through exotherm. C. Sprinkling all of the weld seams and the surrounding backing with graphite talc, followed by 2- layers of 1 1/2 oz. chopped strand mat utilizing the same resin of construction. These conductive options allow for the ability to inspect the liner after the equipment is completed, as well as to check on the integrity of the liner after it has been in service by utilization of a spark test. The bonding laminate is considered as a part of the structural wall for overall thickness, because the thermoplastic liner is the corrosion barrier of the equipment. 2.4.4 Structural Laminate The laminate construction shall comply with ASTM C-582. The design and fabrication of the structural laminate is to be in accordance with ASME RTP-1, ASTM D-3299, D-4097 and BS 4994 as applicable. 2.4.5 Exterior Laminate The exterior laminate and any additives or gel coat shall be as specified and agreed upon between Composites USA and customer. 2.5 Accessory Items Materials of construction for accessory items such as fasteners, gaskets, lugs, braces, brackets, etc. shall be as specified. 3. WELDING 3.1 Welder Qualification All welders must successfully pass the minimum requirements for the weld integrity tests, per ASTM C-1147 and BS 4994 Section 1.3, as is applicable. Any welder who has not been actively welding for a period of 2 months shall be re-tested to assure the required skill level. 3.2 The welding procedures are as specified in BS 4994. 3.2.1 Seam preparation consists of beveling the sheet at approximately 45o, with the bevel on the side from which the welding will be done. The bevel should end with 1/32" (0.75mm) of sheet thickness unbeveled. With fabric or glass backed sheet, the sheet backing must be cleared from the weld area, so that none of the fibers will contaminate the weld. This must be kept to a minimum, unless a fabric or glass backed cap strip is to be used. When using a backed cap strip, the backing can be removed 1/2 the width of the cap strip on each side of the weld. The seam to be welded will have a 1/32 " (0.75mm) gap left between the two parts to assure a good penetration root weld. 3.2.2 Dual laminates should always be welded from the outside, if the sheet is 0.090" (2.5mm) or less and if the diameter does not allow for access. The welds shall be placed on flats and away from corners, whenever possible as shown as preferred fabrication in BS-4994 Section 18.4.1. This places the seams outside of the high stress areas, and allows for better welds. Corners and connections where 90o turns are common shall be thermoformed, thus eliminating the requirement for welding in the corners where possible. 3.2.3 When doing fabrication involving thermoforming and hot gas welding it is necessary to perform the tasks at the proper temperature to assure quality fabrication. Table 1, gives a basic outline on temperatures to use for the different processes to be carried out, as well as the requirements for the type of gas to be used when welding. 3.2.4 An in house welder certification and evaluation program shall be maintained. This is to assure proficiency of technicians and the quality of the equipment produced. The performance of weld tests and evaluations in house shall be made with the use of precision testing equipment and conform to the appropriate ASTM or DIN standard listed in Section 1.3 of this specification. 3.2.5 After completion of the welding all the seams will be spark tested prior to cap strip being applied and retested before application of the bonding laminate. (See Test Procedures 6.1 - 6.1.3) Table 1   OF / OC PVC CPVC PP PVDF PVDF AS ECTFE ETFE FEP PFA Welding Temp*   475 / 245 520 / 270 555 / 290 600 / 315 585 / 310 615 / 325 650 / 342 725 / 405 761 / 405 Forming Temp   200 / 95 250 / 120 300 / 150 335 / 175 325 / 162 350 / 178 365 / 185 550 / 287 575 / 302 Inert Gas   No No Yes No No Yes Yes No No * Temperature measured 3/16" (5 mm) in front of welder nozzle. 3.3 Nozzles and Manways 3.3.1 Fabrication of nozzles using sheet material is to be in accordance with Sections 3.1 through 3.2.5. 3.3.2 Flange face liner shall be of one piece, full face or stub end with a backup ring, construction for nozzles up to and including 30" diameter, 150# ASA B16.5 dimensions. The flange or stub end face being thermoformed so that the connection weld to the nozzle neck takes place in the neck, as shown in Figure 1. 3.3.3 The preferred method of connecting the nozzle to tank or vessel wall is by thermoforming in such a way that the weld takes place in the nozzle neck, as shown in Figure 1. This method normally takes place after the structural wrap of the vessel body or head has been finished. 3.3.4 The minimum size for nozzles fabricated and installed per 3.3.2 & .3 is 2". Nozzles smaller than 2" or threaded connections will require welding on the inside and outside without a cap strip, per BS 4994, as shown in Figure 2. The use of a fabric or glass backed cap strip to the coupling, above the weld bead, is to allow for the RTRP laminate to bond to the fitting. 4. RTRP FABRICATOR QUALIFICATIONS Fabricators shall meet the minimum requirements for lay up and secondary bonding physical properties as outlined in ASME RTP-1 and BS 4994 as are applicable. 5. TOLERANCES The tolerances governing the liner, the structural and the overall for the equipment shall be governed by ASME RTP-1 and BS 4994 standards as are applicable. 6. TESTING The Composites USA Vessel Inspection Report shall be used for documenting final product quality. This report meets the requirements of ASME RTP-1 and BS4994. 6.1 Spark Testing 6.1 Spark testing with a hand held high-voltage, high-frequency probe. The voltage shall be set at a range of 10,000 volts for welds, which do not have a cap strip, and 20,000 volts for welds, which do utilize a cap strip. 6.2 If a weld fails to pass the spark test it must be repaired. The repair procedure consists of the following: Grind out the pinhole and a minimum of 1" on either side of the failed area. Re-weld, then re-test the affected area. Install the cap strip, if applicable, then re-test again. A final spark test shall be performed after the hydrostatic test (if required) has been completed. 6.3 Test certificates shall be issued upon the satisfactory completion of the required tests, per ASME RTP-1 and BS-4994, Section 32. 6.2 Visual Inspection Visual inspections are to be carried out in accordance with ASME RTP-1 and BS 4994 as is applicable. Visual examination shall be required prior to the bonding laminate being applied. After the bonding laminate has been applied and again prior to the application of any gel coat, after the structural laminate is finished. The Visual inspection of the liner is required. Special attention must be focused on the weld seams and the thermoformed parts, for charring or cold welds and for thinning or stretching during the thermoforming. 6.3 Dimensional Checks Dimensions shall comply with the requirements set out by ASME RTP-1 and BS 4994 as is applicable. Dimensional checks of the liner prior to overlay must take into account the shrinkage of the RTRP and this must be designed into the fabrication of the liner. 6.4 Hydrostatic Testing 6.1 When required, shop hydrostatic testing of dual laminate equipment will be completed as noted in the Composites USA, Inc. proposal and as agreed with by the customer. 6.2 A final spark test shall be performed after the hydrostatic test has been completed. 6.3 Test certificates will be issued upon the satisfactory completion of the required tests, per BS-4994, Section 32.
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