FLEXIBLE COUPLINGS RU-STEEL Annex Atex 95 Index: 1 Coupling s Choice 2 Assembly and Alignment 3 Simultaneous Alignment Check 4 Coupling s Guard 5 Check Intervals 6 Extraordinary Malfunctions, Causes and Solutions. 7 Temperatures. 8 Hazardous Areas. 9 Certification. 1) COUPLING S CHOICE. COUPLING S CHOICE PARAMETERS IN HAZARDOUS AREAS. In hazardous areas IT IS RECOMMENDED once a Flexible Coupling is selected, to apply suitable service factors. General criteria are listed in the table below. Anyway, DO NOT CHOOSE a service factor LOWER THAN 2. Carefully check that the starting torque does not exceed the nominal torque twice its value, and less than five start-ups per hour; on the contrary, you are kindly requested to contact our Technical Department. UNIFORM LIGHT MEDIUM HIGH SAFETY FACTOR Constant Torque Centrifugal Pumps, small convectors, alternators, centrifugal compressors. Non-floating torque Machine tools, screw-pumps, liquid ring compressors. Floating torque Reciprocating pumps, low viscosity mixers, cranes. High torque with extraordinary floating Rotary presses, reciprocating compressors, high viscosity mixers. Electrical motor drive or Gas/Steam Turbines Steam Engines Water Turbines 2,0 2,25 2,5 3,0 3,0 3,5 3,5 4,0 pag.1 di 8
2) ASSEMBLY AND ALIGNMENT ASSEMBLY RULES AND STARTING ALIGNMENT OF THE COUPLING Correct starting alignments will allow changing of conditions during operations and thus a long trouble-free life to the coupling. The hubs shall be connected so that the shafts head is aligned with the flanges: the distance between the two flanges will be equal to the S value (see catalogue) in case the coupling has got just one flexible element and to the complete DBSE value in case the coupling has got two flexible elements. Once the machines are correctly placed, you must place a line on the hubs flanges every 90 thus obtaining a starting alignment both horizontal and vertical. Then proceed to check the axial alignment which must bhe within the limits indicated below: Axial Alignment One-flexible element couplings Two flexible element couplings 6 screws Couplings: -0/+0,4 of value S 6 screws Couplings: -0/+0,8 of value DBSE 8 screws Couplings: -0/+0,25 of value S 8 screws Couplings: -0/+0,5 of value DBSE "DBSE" - "S" If you are dealing with a two-flexible elements coupling, it is suggested to increase the nominal value DBSE from 0,5mm to 1mm. The flexible elements will be in traction and the chance of DBSE axial misalignment will be reduced. Start assembling the flexible element or elements, complete with spacer, by tightening nuts with their respective bolts. Taglia / Size Table of driving torque of flexible element's screws Coppia Serr. / Torque Nm Taglia / Size Coppia Serr. / Torque Cl. 12.9 inox A4 Cl. 12.9 inox A4 RSP0010 17,5 7-9 RSP0900 1800 682-909 RSP0015 17,5 7 9 RSP1200 1800 682 909 RSP0030 41,6 17 22 RSP1500 1800 682 909 RSP0070 84,6 33-44 RSP2000 1800 682 909 RSP0110 143 57-76 RSP2500 1800 682-909 RSP0170 143 57-76 RSP3500 2490 903-1240 RSP0260 242 91-121 RSP5000 3275 1260-1600 RSP0400 480 195-261 RSP6500 3995 1620-2160 RSP0700 728 263-364 Nm NB. The indicated tightening torques are valid for calibrated screws which tighten the flexible elements. With RSP and RPA executions, complete with DBSE, you must tighten the screws for the hubs (see standard tightening torques for screws UNI 5739 8.8). pag.2 di 8
Radial and Angular Alignment Use an electronic gauge to calculate the minimum distance between the flanges surfaces, then reset it and find the maximum value, divide it by the flange s diameter, the result mustn t exceed the parameters below: 6 Screws Coupling: 0.0030 mm per mm of the flange diameter 8 Screws Coupling:: 0.0020 mm per mm of the flange diameter Use a centesimal gauge to find the distance between the flanges internal surfaces and gain the maximum value A and the minimum B. Relating it to the flange s diameter D: A A B = maximum misalignment in mm, D which mustn t exceed the indicated Values. D B Repeat the operation with two flexible elements couplings on both sides of the coupling, or proceed to block one of the coupling s side, inserting a ground thickness between the flanges equal to value S. Then, tighten the part using clamps stiffening one side. After this operation, proceed, on the other side of the coupling, to check the process making sure that the compared values must be doubled. pag.3 di 8
3) SIMULTANEOUS ALIGNMENT CHECK TO BE CARRIED OUT AFTER THE FIRST START-UP Some time is likely to go by, in between the assembly moment and the starting of operations and other factors may occur: structures settlements and changings of conditions may have compromised the starting alignment. In order to insure a perfect functioning to the coupling and to avoid danger in hazardous areas IT IS RECOMMENDED to check again all the misalignments, ANGULAR, AXIAL, PARALLEL before starting the engine; it is suggested to compare the values you found with the table below. It is recommended to proceed to such a check even after the first start-up. Coupling Size Nominal Torque Tkn Angular max No spacer Angular max With Spacer Misallignments Axial max No Spacer Axial max With Spacer Parallel max With Spacer Nm mm Mm ± mm 10 98 0,75 1,50 0,85 1,70 0,30 15 147 0,75 1,50 1,00 2,00 0,40 30 294 0,75 1,50 1,30 2,60 0,50 70 687 0,75 1,50 1,50 3,00 0,70 110 1.079 0,75 1,50 1,75 3,50 0,80 170 1.668 0,75 1,50 2,10 4,20 0,90 260 2.551 0,75 1,50 2,40 4,80 0,90 400 3.924 0,75 1,50 2,60 5,20 1,40 700 6.867 0,75 1,50 2,60 5,20 1,40 900 8.829 0,75 1,50 2,65 5,30 1,40 1.200 11.772 0,75 1,50 2,90 5,80 1,40 1.500 14.715 0,75 1,50 2,95 5,90 1,40 2.000 19.620 0,50 1,00 3,15 6,30 1,00 2.500 24.525 0,50 1,00 3,30 6,60 1,20 3.500 34.335 0,50 1,00 3,50 7,00 1,60 5.000 49.050 0,50 1,00 3,80 7,60 1,70 6.500 63.765 0,50 1,00 4,30 8,60 1,80 8.000 78.480 0,50 1,00 4,45 8,90 1,90 10.000 98.100 0,50 1,00 4,60 9,20 2,00 13.000 127.530 0,50 1,00 4,75 9,50 2,10 16.000 156.960 0,50 1,00 5,05 10,10 2,30 20.000 196.200 0,50 1,00 5,40 10,80 2,50 25.000 245.250 0,50 1,00 5,80 11,60 2,60 30.000 294.300 0,50 1,00 6,25 12,50 2,80 CAUTION: the indicated values are max. f the others are 0. In case of angular, axial and simultaneous parallel misalignments, you must follow the table below in order to correctly operate. Max. Simultaneous Misalignments allowed, check tables. Example 1 Mis. Ang. = 25% Mis. Par. ±mm = 50% Mis. Axi. mm = 25% Example 2: Mis. Ang. = 37,5% Mis. Par. ±mm = 67,5% Mis. Axi. mm = 0% Mis. Tot. = Mis. ang. + Mis. Par. + Mis. Axi. 100% Angular Misalignment % 100 75 50 25 0 Axial Misalignment mm % ±mm 2x CAUTION In hazardous areas it is especially recommended to keep a total simultaneous misalignment within 80%. 0 25 50 75 100 Parallel Misalignment ±mm % ±mm pag.4 di 8
4) COUPLING S PROTECTION COUPLING S PROTECTION IN HAZARDOUS AREAS The coupling must be always protected by the user, with a cover (if possible made out of stainless steel) which guards the coupling against falling objects. There can be regular openings in the coverings which may not exceed the diameter of 4mm or, if square-shaped, 4mm each side. - The distance between the coupling s surface must be min. 5mm - The protection must be tightened with bolts; it can be removed when the machines are not working and are safe. - In normal conditions, check if vibrations or noises occur. 5) CHECK INTERVALS CHECKS TO BE CARRIED OUT IN HAZARDOUS AREAS. A first check must be done after the first 2000 hours of operation or max. after 3 months since it has started working. - Check the coupling very carefully. - Make sure that the flexible elements are properly assembled and in order. If so, they shan t show damages, distortions, cracks and possible bleu stains on the coupling s surface. If you don t come up against any problems, it is possible to plan further checks within 4000 hours working or after a year. On the contrary, if you come across some of the above mentioned problems, immediately proceed to remove the damaged flexible element. CAUTION: using RPD or RSP replace both the flexible elements even though one of those isn t visible damaged. Before starting the operation again, it is suggested to find out the reason of the damage following the information at point 6. 6) EXTRAORDINARY MALFUNCTIONS MAIN CAUSES AND SOLUTIONS CAUTION: If irregularities take place during operation the motor drive must be stopped. The main causes of these malfunctions can be found in the table below and, if possible, resolved. Anyway it is recommended to carefully examine the complete transmission. Malfunction Increase of noisiness during operation or beginning of vibrations Causes Danger in hazardous areas Excessive Misalignment ------- Loosening screws, micro frictions at screw s head. Loosening of the fixing dowel, chance of axial movements of the hubs. Starter danger to a possible increase of temperature -------- Solution. 2) Eliminate the cause of misalignment (ex. Machines motions, structural failure etc.) and check the left simultaneous misalignments as shown at point 3. 3) Plan coupling s checks following the directives expressed at point 5. 2) Check coupling s parts and replace the damaged ones 3) Tighten the screws till reaching the tightening torque as shown at point 2. 4) Check the alignment and correct it,if necessary, as shown at point 3 5) Plan the coupling s checks following the directives at. 2) Check the alignment and correct it,if necessary, as shown at point 3 3) Tighten the fixing dowel of the hub.. 4) To avoid a further loosening it is recommended to use a thread-breaking product. 5) Plan the coupling s checks following the directives at pag.5 di 8
Malfunction Breaking of complete flexible elements Breaking of complete flexible elements and tightening screws Causes Excessive Misalignment Flexible elements breaking due to overloading or short circuit. The operative parameters do not match with the coupling s capacity Service error in the operation unit ex. Stop of a rotor Excessive Vibrations in the operating unit Danger in hazardous areas Solution 2) Disassemble the coupling and remove the flexible elements left 3) Check coupling s parts and replace the damaged ones 4) Insert the new flexible elements an assemble them 5) Eliminate the cause of misalignment (ex. Machines motions, structural failure etc.) and check the left simultaneous misalignments as shown at point 3. 6) Plan the coupling s checks following the directives at 2) Disassemble the coupling and remove the flexible elements 3) Check coupling s parts and replace the damaged ones 4) Insert the new flexible elements an assemble them 5) Find out the reason of overloading 6) Plan the coupling s checks following the directives at 2) Check the operative parameters and select a higher power coupling ( consider the assembly space S or DBSE ) 3) Assemble the new coupling 4) Check the alignment as shown at point 3 5) Plan the coupling s checks following the directives at 2) Eliminate the service error 3) Disassemble the coupling and remove the flexible elements 4) Check coupling s parts and replace the damaged ones 5) Insert the new flexible elements an assemble them 6) Plan the coupling s checks following the directives at 2) Disassemble the coupling and remove the flexible elements 3) Check coupling s parts and replace the damaged ones 4) Insert the new flexible elements an assemble them 5) Check the alignment and correct it,if necessary, as shown at point 3 6) Find out the reasons of vibrations 7) Plan the coupling s checks following the directives at pag.6 di 8
7) Temperatures OF EXERCISE, ENVIRONMENTAL CAUTION: The classes of temperatures shown must be regarded just as a point of reference. As a matter of fact RU- STEEL flexible couplings are designed to work between -20 C and +280 C, actually beyond safety limits to avoid possible dusts fire or flammable gas. 8) HAZARDOUS AREAS CATERGORIES, GROUPS, AND CODES. HAZARDOUS AREAS previous classifications Guard level Gas Dust Very high. Zone 0 Zone 1 Zone 2 Zone 20 Zone 21 Zone 22 High. Normal. Group I mine Group II industry Explosion Classes of temperature CATEGORY Group II T6 85 C T5 100 C M1 M2 1 2 3 G for gas D for dust G/D both IIA T4 135 C T3 200 C IIB T2 300 C T1 450 C IIC Example of a coupling s marking: II 2G/D c IIB T4-20 C Ta +80 II Group 2G/D Category as the previous classification zone 1 and zone 21 c Type of protection IIB Suitable against explosive gas of group IIB T4 Temperature class Ta from 20 C to + 80 C Environmental temperature CAUTION: La RU-STEEL is not taking any responsibilities about the improper use of its product and spare parts or nonoriginal accessories 8) HEAD FITTING HEAD Warning: Prior to installing the coupling, ensure that the machinery is made safe. Hubs must be adequately supported during installation to avoid accidental damage should they slip. Ensure the hub bore and mating shaft are clean. Parallel Bore with Keyed Drive The hub is usually installed with the hub face and shaft end flush. 1. Measure the shaft diameter and hub bore to confirm the correct fit. 2. For clearance fits, install the key(s) into the shaft keyway and with a little lubrication on the shaft, slide the hub onto the shaft. The key should be a tight sliding fit in the keyway with a small clearance at the top of the key. 3. It may be necessary to apply heat to assist fitting of such hubs. A warm oil bath will usually be adequate. DO NOT use spot heat or exceed 200 degrees centigrade as this may cause distortion or hardness decrease. A thermal heat stick can be used to estimate the temperature before quickly sliding the hub onto the shaft. Issued by AQ. Bedin Signature Bedin Giacomo Edt. 1 Rev.1 08-01-2004 pag.7 di 8
9) CONFORMITY CERTIFICATE CERTIFICATE OF CONFORMITY In accordance with the directive 94/9/CE standard dated 23/03/1994 The Manufacturer RU-STEEL Italia srl I-20060 Liscate states that: Flexible Couplings RU-STEEL types Type Quantity No. Order Date RP... RPD... RPA... RSP... in no-spk.ex described in these choice directives, assembly, alignment, check e maintenance, in hazardous areas, are designed and projected in accordance with the directives of the Annex II of the standard directive 94/9/CE. The exam carried out meets the requirements of the Annex VIII the standard directive 94/9/CE. Technical Dossier registered by BUREAU VERITAS No. of filing ATEX/ITA/40.20034516 Issued by AQ. Bedin Edt. 1 Rev.1 Signature Bedin Giacomo pag.8 di 8