BR 31a Rack-and-pinion Actuator,

Transcription

1 Operating, assembly and maintenance instructions BR 31a Rack-and-pinion Actuator, SRP and DAP 1. General These instructions are intended to support the user in the assembly, maintenance, and repair of BR 31a Rack-andpinion Actuators. Before operating the unit, please read this manual thoroughly and retain it for future reference. Fig. 1 - Rack-and-pinion actuator 0. Contents 1. General 1 2. Design, principle of operation, and dimensions 1 3. Actuator designation and nameplate 1 4. Operating conditions Design Warnings Operating media Supply pressure Operating temperatures Response time Rotation and travel limitation Lubrication Coating and corrosion protection Function and direction of rotation Fail-safe position 4 5. Actuator design und mounting instructions Principle of operation Important safety instructions Control and connections Mounting accessories Mounting the actuator onto valves Changing the direction of action/fail-safe position Alternative mounting options 6 6. Maintenance and assembly instructions Fourth generation of rack-and-pinion actuators (version manufactured from 2000) 6.2 Third generation rack-and-pinion actuators Storage instructions Customer inquiries 18 Technical specifications, as a result of further development of valves mentioned in these instructions are subject to alteration without notice. The text and illustrations do not necessarily display the scope of supply or any ordering of spare parts. Drawings and graphics are not to scale. Customer-specific designs not in accordance with our standard product range are not shown. Parts subject to wear are not covered by the warranty. The device may only be mounted and started up by skilled staff who are familiar with the assembly, start-up, and operation of this product. In these maintenance and assembly instructions, the term skilled staff refers to individuals who are able to judge the responsibilities assigned to them as well as recognize potential hazards due to their specialized training, knowledge, and experience as well as their special knowledge of the relevant standards. These instructions apply to the actuator only. In addition, refer to the instructions of the mounted valve. 2. Design, principle of operation, and dimensions Design, principle of operation, and dimensions including all further details and technical data can be found in the Data Sheet <TB 31a>. 3. Actuator designation and nameplate The actuator type, size, operating pressure, output torque, direction of rotation, fail-safe action, operating temperature, and type of attachment are determined by the actuator designation. 1 of 18

2 Maximum permissible pressure (fixed) 6 Always 10 bar for BR 31a Principle of operation (variable) 7 Actuator function: Single-acting/double-acting 8 Direction of action: CW = Clockwise CCW = Counterclockwise 9 Schematic diagram of the spring function with the air connection. Schematic diagram of NAMUR interface with identification for ports 2 and 4 Exact type designation (variable) 10 Series: BR 31a 11 Type: SRP / DAP 12 Actuator size: 6 to Spring designation: 2,5 to 6 (bar) Opening angle (fixed, depending on actuator size) /-15 ; /+5/-15 ; /-15 ; Article number (variable) 15 Pfeiffer article number Version acc. to EN (fixed, depending on actuator size) Example: F07-Y-D Flange F07 17 Spigot ( Y ) 18 Diagonal square drive ( D ) 19 Square drive, width across flats 17 Torques (variable) 20 Specification of the actuator torque depending on supply pressure. 4. Operating conditions 4.1 Operating conditions The rack-and-pinion actuator is suitable for use in closed and open environments without additional weather protection. Fig. 2 Name plates Rack-and-pinion actuators have nameplates, which show the following information: Unique identification (variabel) 1 Order number 2 Position number in the order 3 Serial number (automatically assigned) Connection for accessories (fixed, depending on actuator size) 4 AA1 to AA5 (VDE/VDI actuator size 1 to 4) Pressure connection (fixed, depending on actuator size) 5 PC1 = G 1/8 PC3 = G 3/8 PC2 = G 1/4 PC4 = G 1/2 4.2 Warnings: Referring to the Machinery Directive 2006/46/EU, the actuators can be classified as partly completed machinery (see declaration of incorporation). As a result, the actuator cannot put into service until the machinery and/or the system, into which the actuator is to be incorporated, has been declared in conformity with the provisions of the Directive 2006/42/EU. Actuators are designed, produced, and classified according to the ATEX Directive 2014/34/EU. The use of the actuators in potentially explosive atmosphere zones must comply with the ATEX classification indicated on the actuator nameplate and according to the ATEX safety regulations. It is important that the actuator is used only within the working limits permitted in the technical specifications. 2 of 18

3 Do not operate the actuator outside the temperature limits: this could damage internal and external components (disassembly of single-acting actuators may be dangerous). Do not operate the actuator outside the pressure limits: this could damage internal parts as well as cause damage to the housing and end caps. Do not use the actuator in corrosive environments with insufficient protection: this could damage internal and external parts. Do not disassemble individual spring cartridges; this may result in personal injury. If maintenance to springs is necessary, send them to Pfeiffer. Close and disconnect all air supply lines and make sure that pneumatic connections are vented during maintenance and when mounting the actuator onto the valve. Do not disassemble the actuator or remove the end caps while the actuator is pressurized. The actuators are designed to be used only on valves. Before mounting the actuator onto the valve, make sure that the direction of rotation and the position indicator are in the correct position. If the actuator is incorporated into a system or must be used in safety devices or circuits, the operator must ensure that the national and local safety laws and regulations are observed. 4.3 Operating media: Dry or lubricated air or inert gases, provided that they are compatible with the actuator s internal parts and lubricant used. Note: The operating media must have a dew point equal to -20 C (-4 F) or at least 10 C below the ambient temperature. The maximum particle size contained into the operating media must not exceed 30 μm. 4.4 Supply pressure: The maximum supply pressure is 10 bar (145 psi). For double-acting and single-acting actuators, the operating pressure range is 2.5 bar (36 psi) to 10 bar (145 psi). 4.5 Operating temperatures: Standard actuator: from -40 C (-40 F) to +80 C (+176 F). Low-temperature version SLT with silicone O-rings: from -55 C (-67 F) to +80 C (+176 F). High-temperature version HT with FPM O-rings: from -15 C (+5 F) to +150 C (+300 F). Note: For operation at low and high temperatures, special lubricant is required. Please contact Pfeiffer. A low or high temperature can slightly influence the torque of the actuator. 4.6 Response time: Refer to the corresponding data sheets for the response times. Note: The response time depends on several factors, e.g. supply pressure, supply capacity of the operating medium (pipe diameter, flow capacity of pneumatic accessories), valve type, valve torque and characteristics, applied safety factor, operating frequency and temperature etc.). 4.7 Rotation and travel limitation: Refer to the data sheet for the travel of the rack-and-pinion actuators: Standard actuator: 90 rotating angle, with end stop setting at 0 and 90, +5/ 15 adjustable 120 actuator: 120 rotating angle with end stop setting at 0 and 120, +5/ 15 adjustable 180 actuator: 180 rotating angle with end stop setting at 0 and 180, +5/ 15 adjustable 4.8 Lubrication: The actuators are delivered ready lubricated for the service life of the actuator under normal operating conditions. The standard lubricant is approved for the temperature range from -40 C (-40 F) to +80 C (+176 F). For low (SLT) and high (HT) temperatures, a special lubricant is required. Contact Pfeiffer in this case. Manufacturer Lubricant Tennex TS 2066/2 Table 1 - Lubricant recommendation 4.9 Coating and corrosion protection: All actuators are protected against corrosion under normal weather conditions. The different types of coating are described in the data sheet Note: Before mounting the actuator in a corrosive environment, make sure that the correct type of corrosion protection has been chosen. 3 of 18

4 4.10 Function and direction of rotation: Fail-open: counterclockwise (SRP only) The actuator is a pneumatic component for remote actuation of valves. For the actuation (90, 120 or 180 rotation), there are different actuator versions: Direct mounting of a solenoid valve (5/2 or 5/3-way for double acting, 3/2-way for single acting) for connecting to ports 2 and 4. Hook-up (to ports 2 and 4) with a separate control unit. The standard direction of rotation is the clockwise direction to close a mounted valve. The counterclockwise direction for double-acting actuators is achieved by applying air pressure to port 2. For actuators marked CCW, the direction of rotation to close the valve is counterclockwise, the clockwise direction of rotation (CW) is achieved by applying air pressure to port 2. Fig. 4 - CCW direction 4.11 Fail-safe position: Fail-close: clockwise (SRP only) If the shaft of the actuator is to turn in a clockwise direction when the valve opens, the pistons must be installed in the opposite way to the standard version (see Fig. 4). The shaft turns from the start position OPEN to the end position CLOSED in clockwise direction (SRP only). The actuator is delivered in the start position. 5. Actuator design und mounting instructions The BR 31a Actuator operates with a 90 (optionally 120 or 180 ) angle of rotation to open and close different types of valves Fig. 3 - CW direction Note: All the necessary technical information to correctly mount the actuator onto a valve, e.g. dimensions, output torque, air volume, travel adjustment, response time, operating temperature, and direction of rotation are clearly stated on the nameplate, in the catalog and/or data sheets. Read the technical information carefully before proceeding with mounting the actuator. The standard version of the Series 31a Actuators is mounted in the direction of the media flow. When pressure is applied to port 2, the shaft turns from the start position CLOSED to the end position OPEN in the counterclockwise direction. In case of pressure loss at port 2, the shaft turns clockwise to the start position CLOSED (SRP only). The actuator is delivered in the start position. Note: If mounted diagonal to the media flow, make sure that the position indicator is set correctly (turn 90, see mounting instructions 5.1 Principle of operation: Double-acting actuator (standard direction of rotation) Fig. 5 Fig. 6 4 of 18

5 Air supplied to port 2 (Fig. 5) forces the pistons apart and towards the end positions. Air is vented at port 4. This is based on a clockwise direction of rotation. 5.3 Control and connections: Air supplied to port 4 (Fig. 6) forces the pistons together. Air is vented at port 2. This is based on a clockwise direction of rotation. Single-acting actuator (standard direction of rotation) Fig. 9 Connections Fig. 7 Fig Mounting accessories Air supplied to port 2 (Fig. 7) forces the pistons apart and towards the end positions. The springs are compressed. Air is vented at port 4. This is based on a clockwise direction of rotation. A loss of air pressure at port 2 (Fig. 8) allows the pistons to return to the start position. Air is vented at port 2. This is based on a clockwise direction of rotation. 5.2 Important safety instructions For safety reasons, the actuator must not be pressurized when mounting the actuator onto the valve. Risk of injury. When connecting the air pressure to the actuator, it is important that all connecting parts are clean and free from dirt, especially the thread connections, pipe screw fittings, and gaskets. When fitting accessories to the actuator, make sure that the emergency operator control of the solenoid valve and the top end of the shaft are easily accessible for possible manual operation of the actuator. Before mounting the actuator onto the valve, make sure that the actuator is correctly aligned based on the direction of rotation required. For single-acting actuators, make sure dangerous and/or corrosive substances in the working environment cannot enter the spring chambers through the use of suitable filters and/or solenoid valves. Remove plugs from the actuator s pneumatic connections during installation and operation. Protect any unused pneumatic connections of actuators. Fig Mounting accessories Mounting the solenoid valve: Before mounting the solenoid valve, check that the actuator is in the initial position (closed position, pistons retracted). For standard mounting and clockwise rotation (closing): The groove on the shaft or position indicator (2) must be in the closed position, at a right angle to the longitudinal axis of the actuator. Mount the solenoid valve (4) onto the actuator (3) using the suitable screws (see Table 2 for max. tightening torque). Mounting the limit switch box: Fit the limit switch box and bracket (1) onto the actuator (3) using suitable screws (see Table 2 for max. tightening torque). Screw M5 M6 M8 M10 M12 M14 M16 M20 M24 M30 Tightening torque in NM Table 2 - Tightening torque of 18

6 5.5 Mounting the actuator onto valves: Fig Mounting the actuator onto valves Note: Before mounting the actuator onto a valve, ensure that the actuator turns in the required direction of rotation and that the valve and actuator are correctly aligned with each other. Caution: When mounting a single-acting actuator (with spring) with a defined fail-safe position, ensure upon pneumatic or electric power failure that the direction of rotation is according to your application. (clockwise to close). Mount the actuator ( 3 ) onto the valve ( 5 ). The actuator must be in the initial position (CLOSED position). There are two different mounting versions: Direct mounting: Insert either the square drive, flat head drive or key drive of the valve shaft directly into the actuator shaft. Fasten them using the ISO flange onto the actuator. See Table 2 for max. tightening torque. Mounting using a bracket: Mount the bracket (6) onto the valve (5) and place the coupling (7) onto the actuator shaft. Note: Make sure that the position indicator of the coupling corresponds with the switching position of the valve. Place the actuator onto the shaft and fasten the unit. See Table 2 for max. tightening torque. 5.6 Changing the direction of action/fail-safe position Note: For the exact procedure for disassembly and assembly, refer to section 6 (maintenance and assembly instructions). Move the actuator to the fail-safe position to release the spring compression. Remove the screws ( 24 ) (see Fig. 15). Pull the position indicator ( 19 ) off the end of the shaft. If necessary, use a screwdriver to lever it off. Remove both adjusting screws ( 2 ) with washers ( 4 ) and lock nuts ( 3 ) (see Fig. 16). Remove the O-ring ( 11 ). Unscrew the screws ( 13 ) of the end caps (see Fig. 17). Remove end caps ( 22 und 23 ) from the housing. For single-acting actuators, remove the spring cartridges ( 17 ). Remove the gaskets ( 14 ) of the end caps. Clamp the housing ( 29 ) in a vise or similar. Turn the shaft ( 30 ) until the pistons ( 25 ) are released (see Fig. 18). Turn both pistons ( 25 ) in axial direction by 180 and reassemble. Press both pistons ( 25 ) simultaneously into the housing ( 29 ) until they engage and turn the housing until the travel end position is reached. Check that the pistons are in the end position. Turn the shaft 4 over the center line (0 ) (see Fig. 25). For single-acting actuators, insert the spring cartridges into the end caps (see Fig. 27). Insert the gasket ( 14 ) into the groove of both end caps. Mount the end caps on the housing ( 29 ). Tighten the screws ( 13 ) by hand. Observe the tightening sequence (see Fig. 28). Insert the adjusting screws ( 2 ), lock nuts ( 3 ), washers ( 4 ), and O-rings ( 11 ). Screw the adjusting screws ( 2 ) into the housing. Observe the end position setting. Place the position indicator ( 19 ) onto the shaft. Make sure that it is in the correct position (see Fig. 30). Tighten screw ( 24 ). 5.7 Alternative mounting options: Alternative mounting options (in clockwise direction to open) 6 of 18

7 6.1 Fourth generation of rack-and-pinion actuators (version manufactured from 2000) Screw sizes Fig Clockwise direction to close Valve mounted with an actuator: (in clockwise direction to open) Actuator DAP/SRP d in mm SW 1 in mm SW 2 in mm SW 3 in mm SW 4 in mm Allen 14 - Table 3 - Dimensions Fig Clockwise direction to open 6. Maintenance and assembly instructions With the information stated below, Pfeiffer provides the end user with all the required information necessary for maintenance. Under normal operating conditions, the actuator requires only periodic checks to ensure proper functioning. Spare part kits for maintenance are available to replace all seals and bearings. Maintenance may be necessary between 500,000 and 1,000,000 cycles, depending on the operating and/or environmental conditions. 7 of 18 Fig Screw sizes (depending on actuator version)

8 Fig Detailed drawing of Series 31a Actuator, version manufactured from 2010 Item Qty. Description Material Item Qty. Description Material 1 1 Cam (end position adjustment) GS O-ring (piston) NBR 2 2 Adjusting screw A Spring cartridge SiCr spring steel 3 2 Lock nut A Spring clip C Washer A Position indicator PP + 30% GF 5 2 Bearing (piston back) Nylon Shaft seal (bottom) NBR 6 1 Shaft bearing bushing (top) PA Shaft seal (top) NBR 7 1 Shaft bearing bushing (bottom) PA Right end cap GD-AlSi8.5Cu3.5Fe 8 2 Thrust bearing Nylon Left end cap GD-AlSi8.5Cu3.5Fe 9 2 Plug (to seal air port) NBR 24 1 Screw (position indicator) A Thrust washer Piston GD-AlSi8.5Cu3.5Fe 11 2 O-ring (adjusting screw) NBR 26 1 Nameplate Polyester aluminium 12 2 Piston guide Nylon % GF 27 2 Nameplate (end cap) Polyester aluminium 13 8/12/16 Screw (end cap) A Spigot EN AW Gasket (end cap) NBR 29 1 Housing EN AW Bearing (piston head) POM 30 1 Shaft C22 Table 4 - Parts list 8 of 18

9 6.1.2 Disassembly of the actuator: When the actuator must be disassembled for maintenance purposes, first remove the actuator from the valve. Note: Before disassembly, it is important to check that the actuator is not pressurized and the compression is relieved from the actuator springs (end position). Always use caution and check that ports 2 and 4 are vented and that all accessories are removed. Before disassembling a single-acting actuator, make sure that the actuator is in the start position and the pistons fully retracted. For single-acting actuators, remove spring cartridge ( 17 ). Remove gasket ( 14 ) and renew it when replacing spare parts. Removing the position indicator (see Fig. 16) Remove screw ( 24 ). Lift position indicator ( 19 ) from shaft. If necessary, use a screwdriver to lever it off. Fig. 16 Removing the adjusting screws: (actuator versions manufactured up to 2006) (see Fig. 17) Remove both adjusting screws ( 2 ) with the washers ( 4 ) and lock nuts ( 3 ). Remove O-rings ( 11 ) and replace them when replacing spare parts. Removing adjusting screws: (actuator versions manufactured from 2006) (see Fig. 17) Remove lock nuts ( 3 ) together with washers ( 4 ). Remove O-rings ( 11 ) and renew them when replacing spare parts Unthread both adjusting screws ( 2 ) and continue unscrewing until their stopping point. Before continuing with the final disassembly, remove the end caps ( 22 and 23 ) and the pistons ( 25 ) since the adjusting screws can only be removed from the inside of the housing. The instructions for dismantling the end caps and pistons are described below. Removing the end caps (see Fig. 18) For sizes 900 to 3000, the end caps ( 22 and 23 ) are symmetric. Remove the screws ( 13 ) in the sequence a-b-c-d (see Fig. 18). Fig. 17 Note: When disassembling a single-acting actuator, loosen the screws of the end caps ( 22 and 23 ) in alternating sequence. If there is still noticable force after 4 or 5 turns on all end cap screws, this may indicate a damaged spring cartridge, and any further disassembly should be discontinued. Further disassambly of the end caps may result in injury. Return the actuator to Pfeiffer for further maintenance. Fig of 18

10 Removing the pistons: (see Fig. 19) Clamp the housing ( 29 ) in a vise or similar device. Turn the shaft ( 30 ) until the pistons ( 25 ) are accessible. Note: Do not apply air pressure to remove the pistons from the housing (projectile impact). Carefully remove the piston O-rings ( 16 ) using a screwdriver. Remove the piston bearing ( 5 ) and piston bearing ( 15 ). Renew gasket ( 14 ) when replacing spare parts. Removing the shaft (see Fig. 20) Use pliers for circlips to carefully remove the spring clip ( 18 ). Remove the thrust bearing ( 8 ) and thrust washer ( 10 ). Push down on the top of the shaft ( 30 ) until it is possible to remove the cam ( 1 ) and the internal thrust bearing ( 8 ). Pull the shaft ( 30 ) all the way out of the housing. If the shaft cannot be removed by hand, gently tap the top of the shaft with a plastic mallet to drive it out. Remove the top and bottom shaft bearings ( 6 and 7 ) as well as top and bottom shaft seals ( 20 and 21 ). Renew the bearing bushings ( 6 and 7 ), internal and external thrust bearing ( 8 ) as well as the seals ( 20 and 21 ) when replacing all the spare parts. Note: Thoroughly clean all dismantled parts as well as any parts that have not been renewed and check them for wear. Fig. 19 Fig Actuator assembly: Note: Before assembly, ensure that all parts are clean and in perfect condition. Use the grease recommended by Pfeiffer (Table 1). Shaft assembly (see Fig. 21, Fig. 22a and Fig. 22b) Mount the top and bottom bearing bushings ( 6 and 7 ) followed by the top and bottom shaft seals ( 20 and 21 ) onto the shaft. Apply grease to the top and bottom of the shaft as shown in Fig. 21. Guide the shaft ( 30 ) partially into the housing ( 29 ) Mount the cam ( 1 ) in the required position, in relation to the top and bottom position of the shaft as well in relation to the direction of rotation of the actuator (see Fig. 22). Place the internal thrust bearing ( 8 ) onto the shaft ( 30 ). Guide the shaft completely into the housing. Mount the external thrust bearing ( 8 ), thrust washer ( 10 ), and spring clip ( 18 ) (using pliers). Fig of 18

11 Fig. 23 Fig. 22a Fig. 24 Fig. 22a Note: For actuators from 2006: The adjusting screws ( 2 ) of this actuator version are mounted from the inside, into the actuator housing. This step must carried out before the piston and end caps are mounted. Mounting the pistons (see Fig. 23, Fig. 24, Fig. 25a, Fig. 25b, and Fig. 26) Mount the the piston O-ring ( 16 ), piston bearing ( 5 ), and piston bearing ( 15 ). Apply grease to the bearing surface of the piston ( 25 ) inside the housing ( 29 ) and the piston rack teeth. Either clamp the top end of the shaft in a vise or hold the shaft stationary with the corresponding counterpart and place the housing ( 29 ) in a horizontal position (see Fig. 23). Make sure that the cam ( 1 ) is in the correct position (see Fig. 24). For the standard direction of rotation (clockwise to close), turn the housing ( 29 ) by 40 to 45 counterclockwise (view from below) or clockwise (view from top), depending on which way the shaft is held (see Fig 25a and Fig. 25b). Press both pistons ( 25 ) simultaneously into the housing ( 29 ) until the pistons are engaged and turn the housing clockwise or counterclockwise (see above) until the travel end is reached. Check the pistons in the end position and turn the shaft 4 over the middle line (0 ) (see Fig. 26). Fig. 25a Fig. 25b Fig of 18

12 Mounting the end caps (see Fig. 27, Fig. 28 and Fig. 29) For actuator sizes 900 to 3000, the end caps ( 22 and 23 ) and spring cartridges ( 17 ) are symmetric (Figs. 27, 28 and 29). Bearing surface of the housing. For single-acting actuators, insert the correct number of spring cartridges (according to table) into the end caps (see Figs. 27 and 28). Fit gaskets ( 14 ) into the grooves of both end caps. Mount the end caps onto the housing ( 29 ), making sure that the gaskets are seated properly in the grooves. Tighten the screws ( 13 ) by hand. Tighten according to the sequence indicated in Fig. 29. Mounting the adjusting screws (actuator versions manufactured up to 2006) (see Fig. 30) Insert adjusting screws ( 2 ), lock nuts ( 3 ), washers ( 4 ) and O-rings ( 11 ). Screw the adjusting screws ( 2 ) into the housing. Fig. 28 Mounting the adjusting screws (actuator versions manufactured from 2006) (see Fig. 30) Both adjusting screws ( 2 ) must be screwed into the housing before the pistons and end caps are mounted because they can only be inserted from the inside of the actuator. Insert the O-rings ( 11 ). Place the lock nuts ( 3 ) and washers ( 4 ) onto the adjusting screws. Adjusting the end position on the standard actuator (in clockwise direction to close) 0 (closed) end position adjustment for an actuator in the closed position: turn the screw ( 2 ) on the right (view from the top) either clockwise or counterclockwise until the required position is achieved. To secure this position, tighten the lock nut ( 4 ). 90 (open) end position adjustment for an actuator in the open position: turn the screw ( 2 ) on the left (view from the top) either clockwise or counterclockwise until the required position is achieved. To secure this position, tighten the lock nut ( 4 ). Fig. 29 Fig. 30 Fig of 18

13 Mounting the position indicator (see Fig. 31) Place the position indicator ( 19 ) on the shaft, making sure that it is in the correct position. Tighten screw ( 24 ). Fig. 32 Fig. 31 The actuator assembly is now completed. 6.2 Third generation rack-and-pinion actuators Actuator disassembly Note: Before disassembly, it is important to check that the actuator is not pressurized and all accessories (e.g. solenoid valves or limit switches) have been removed. Refer to the detailed drawing of actuator (Fig. 39). Removing the cam or position indicator (if fitted) (see Fig. 32) Open the spring clip ( 18 ) using a suitable pair of pliers. Note: Make sure that the spring clip is not stretched too far. Use a tool (e.g. screwdriver) to lift the cam up slightly. O-ring replacement on angle adjusting screw OPEN (see Fig. 33) Undo nut ( 12 ) using a socket wrench. Unthread the adjusting screw ( 10 ) and remove the washer ( 11a ) and O-ring ( 11 ). This must be done on both sides. After renewing the O-ring ( 11 ), slightly tighten the nut (without locking) to tighten the adjusting screw with O- ring and washer. The two adjusting screws are first to be locked properly once the final assembly has been completed and on adjusting the piston. Fig. 33 Fig. 34 Removing the end caps (see Fig. 34) Unscrew the screws ( 13 ) in the sequence shown in Fig. 34. For Type SRP (single-acting), remove the compression springs ( 17 ) as well. Renew gasket ( 14 ). 13 of 18

14 O-ring replacement (with stop screw OPEN) (see Fig. 35) Undo nut ( 12 ) using a socket wrench. Unthread the adjusting screw ( 10a ) and remove the washer ( 11a ) and O-ring ( 11 ). This must be done on both sides. After renewing the O-ring ( 11 ), slightly tighten the nut (without locking) to tighten the adjusting screw with O- ring and washer. The two adjusting screws are first to be locked properly once the final assembly has been completed and on adjusting the piston. Removing the piston (see Fig. 36) After removing the end caps, hold the housing ( 1 ) stationary (possibly in a vise) and turn the shafts until the the pistons on both sides are released. Remove both the pistons on both sides. Use a flat, blunt tool (e.g. screwdriver) to remove the O-ring ( 16 ), piston head bearing ( 15 ), and piston back bearing ( 5 ). Check that both pistons are free of dirt particles, especially at the gears. Renew the O-ring, piston head bearing ( 15 ), and piston back bearing ( 5 ). Fig. 36 Removing the shaft and bearing bushings (see Fig. 37 and Fig. 38) Remove the spring clip ( 18 ) using pliers for circlips and the thrust washer ( 8 ). Push the shaft from the top downward out of the housing (see Fig. 37). Remove the top and bottom bearing bushings ( 6 and 7 ) as shown in Fig. 38. Fig. 37 Fig. 35 Fig of 18

15 Fig Detailed drawing of BR 31a Actuator, third generation Item Qty. Description Material Item Qty. Description Material 1 1 Housing AlMgSi0,5 F Lock nut X5 CrNi Piston GD-AlSi8 Cu Screw (end cap) X5 CrNi End cap GD-AlSi8 Cu3 13a 8 Washer X5 CrNi Shaft C Gasket (end cap) Buna N 5 2 Bearing (piston back) PA Bearing (piston head) PA Shaft bearing bushing (top) PA O-ring (piston) Buna N 7 1 Shaft bearing bushing (bottom) PA Spring cartridge 54 Si Cr6 8 1 Thrust washer PA Spring clip (pinion) C75 8a 1 Support screw X5 CrNi Position indicator PA 9 2 Air port screw Buna N 20 1 Screw/washer X5 CrNi Adjusting screw (OPEN) X5 CrNi O-ring (pinion top) Buna N 10a 2 Adjusting screw (CLOSED) X5 CrNi O-ring (pinion bottom) Buna N 11 4 O-ring (adjusting screw) Buna N 24 2 Guide piston PPA 11a 4 Washer X5 CrNi Centering ring PA Table 5 - List of parts 15 of 18

16 6.2.2 Actuator reassembly after replacement of parts Mounting the actuator shaft and bearing bushings (see Fig. 40, Fig. 41, Fig. 42, and Fig. 43) Apply grease to the shaft as shown in Fig. 40. Push the top bearing bushing ( 6 ) onto the shaft ( 4 ). Apply grease to the surface of the bearing bushing ( 7 ) and the shaft ( 4 ) as shown in Fig. 41. Apply grease to the surface of the bearing bushing ( 7 ) and mount the bushing as shown in Fig. 42. Use the special tool (available from Pfeiffer) to hold the bearing bushing ( 7 ) stationary while pressing in the shaft ( 4 ). We recommend clamping the tool into a vise as shown in Fig. 43. After mounting the shaft, place the thrust washer ( 19 ) on the top shaft end. Mount the spring clip ( 18 ) using pliers for circlips. Fig. 43 Mounting the pistons (see Fig. 44a, Fig. 44b, and Fig 45) Apply grease to the inside running surface of the housing ( 1 ). Clamp the flattened section of shaft in a vise and position the housing in the horizontal position. Align the tooth profile vertically as shown in Fig. 44a and push the two pistons into the housing. To obtain a counterclockwise rotation to close the valve, install the pistons turned by 180 (see Fig. 44a). Turn the housing by 15 to 20 counterclockwise as shown in Fig. 44b. Fig. 40 Fig. 41 Fig. 44a Fig. 42 Fig. 44b 16 of 18

17 Push and turn the housing onto the pistons clockwise until the end of travel is reached. Check that the internal angle adjusting screw does not reduce the travel. This is not necessary if it is to be 90 to 95. The shaft clearance is 3 to 5 more than 0 (see Fig. 45). Fig. 45 Fig. 46 Adjusting the opening angle for 0 position CLOSED To adjust, turn the adjusting screw ( 10a ) until the required position is reached and lock this position with the nut ( 12 ) using a socket wrench. While locking in position, hold the adjusting screw stationary with an Allen key. To ensure that both pistons stop at the same time, turn the adjusting screw at the other piston until you feel resistance and they stop at the shaft. Lock the adjusting screw in the same position with the lock nut ( 12 ). The initial position CLOSED has now been adjusted. Mounting the end caps and compression springs (see Fig. 46 and Fig. 47) Apply grease to the housing. Insert the correct number of compression springs ( 17 ) specified in Fig. 46 and according to the pattern shown in Fig. 46. Fit on the end caps ( 3 ) and check to ensure that the gaskets ( 14 ) are seated properly. Insert the screws ( 13 ) without screwing them tight. Tighten them according to the sequence shown in Fig. 47. Adjusting the switching position to 90 position OPEN (see Fig. 48) External adjustment can only be made after the actuator assembly is completed with the pistons extended as far as they will go on the outside of the housing as shown in Fig. 48. In double-acting actuators, this can be done by turning the shaft. When the actuator has been mounted onto the valve, apply the control pressure to move it to this switching position. Once you have adjusted the switching position on one side, turn the screw on the other side as far as it will go and lock this position. For single-acting actuators (SRP), apply the control pressure to move the actuator to the switching position. Check this position, readjust, and move the actuator to the position again until the required position is reached. Lock the adjusting screw, while using an Allen key to hold the screw stationary and lock it with a special key (available from Pfeiffer). The actuator assembly is now completed. Fig. 47 Fig of 18

18 7. Storage instructions lf the actuators are not for immediate use, the following measures must be taken: Store them in dry environment at normal ambient temperature. We recommend to leave the actuators in their original packaging. Do not remove the plastics plugs on the air supply ports 2 and 4. Size: 15, 30, 60, 100, 150, 220, 300, 450, 600, 900, 1200, 2000, 3000, 4000, 5000 oder Number of springs: only with single-acting Type SRP Fail-safe position: Clockwise or counterclockise rotation of springs (only with single-acting Type SRP) Supply pressure:... bar Operating range: Number of springs or nominal signal range VDI/VDE bracket: To mount positioner or indicating devices 8. Customer inquiries (please specify the following details) Type of actuator: BR31a Typ DAP oder Typ SRP 18 of 18 PDF=166