Steering unit. RE 14365/10.07 Replaces: Type LAGC. Sizes 50 to 630 Component series 1X and 2X Nominal pressure 175 bar Maximum flow 63 l/min

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1 Steering unit E 14365/10.07 eplaces: /12 ype AGC Sizes 50 to 630 Component series 1X and 2X Nominal pressure 175 bar Maximum flow 63 l/min H6211_d able of contents Content age Features 1 Ordering code 2 Function, section 3 Variants 4 and 5 Functions in the steering circuit 5 echnical data, general 6 echnical data of hydraulic fluid with selection diagram 7 echnical data, hydraulic 8 Determination of steering moment 8 Dimensioning of steering cylinder and steering pump 9 Unit dimensions of type AGC.../AGC...D 10 Unit dimensions of type AGC... DA.. 11 Features AGC steering units are used in hydraulic steering circuits of vehicles and mobile machines with large axle loads and travel speeds not exceeding 50 km/h. With the aid of a steering unit even heavy vehicles can easily be steered. he absence of a mechanical connection between the steering unit and steering axle allows the designer to realize solutions, which would be impossible with conventional steering systems. he steering unit includes all valves required in the hydraulic steering circuit for the protection of the steering unit and the steering cylinder. his eliminates the need for additional pipework. If the hydraulic pump fails, vehicles can also be steered manually with the help of the AGC; in this case, the AGC acts as hand pump for the steering cylinder. Information on available spare parts:

2 2/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 Ordering code AG C M * Steering unit Design with integrated valves Displacement (cm3/rev) = C Frame size OC; D 1) ; DA 2) 50 = = = = = = = = = = = = 630 Noise characteristics Standard 3) = ow 4) = N Series Series 10 to 19 = 1X (10 to 19: Unchanged installation and connection dimensions) Series 20 to 29 = 2X 5) (20 to 29: Unchanged installation and connection dimensions) = Standard product range = Extended product range 1) With reaction 2) Dynamic load signal, can be flanged on 3) o be specified for D variant 4) o be specified for Open Center (OC) variant 5) Only Open Center design (extended flow: see echnical data - page 8) 6) For thread dimensions, see Unit dimensions on pages 10 and 11 7) he response pressure of shock valves must be 50 bar higher than the setting of the pressure relief valve, but not exceed 2.2 times the setting of the latter (see 38 StVZO, German oad raffic icensing egulation). referably: 150 to 90; 200 to 140; 240 to 175. = Special specifications lease consult our sales organization 6) ipe ports,,, / D 01 = ipe thread to DIN = Metric ISO thread to DIN = UNF thread to SAE 40 = Metric ISO thread to DIN 3852 Seals M = Suitable for mineral oil (H, H) to DIN and fast bio-degradable hydraulic fluids (HEG, rape seed oil) to VDMA (see E 90221) 7) ressure relief valve setting (pressure differential) 90 = 90 bar 140 = 140 bar 175 = 175 bar 7) Shock valve setting (pressure differential) 150 = 150 bar 200 = 200 bar 240 = 240 bar eaction No code = Without reaction = With reaction oad Sensing No code = Without load signal in Open Center (OC) variant D = Dynamic load signal DA = Dynamic load signal, can be flanged on Order example: 1. AGC 200-1X/D150-90M01 Steering unit with integrated valves Frame size 200, dynamic load signal Shock valves 150 bar, pressure relief function 90 bar ipe ports,,, in G 1/2, D in G 1/4 2. AGC 200 N1X/150-90M01 Steering unit with integrated valves Frame size 200, low noise characteristics Shock valves 150 bar, pressure relief function 90 bar ipe ports,,, in G 1/2 = units stocked in Australia

3 E 14365/ AGC Hydraulics Bosch exroth AG 3/12 Function, section ilot spool (1) of the control valve is rotated via the steering column in relation to control sleeve (2). his opens a cross-section between the spool and the sleeve. he pressure oil acts on rotor set (3) and sets the latter into motion. he oil is then fed via the rotor set to the steering cylinder. he rotation of the rotor acts on the sleeve, which then follows the rotary movement of the spool. he size of the opened cross-section depends on the turning speed of the steering wheel and on the steering pressure; on oad-sensing variants, it depends exclusively on the turning speed. If the steering movement is interrupted and the spool is at a standstill, the oil, which still flows through the open cross-section to the rotor, causes the rotor and hence the sleeve to continue to rotate. he rotary movement then causes the cross-section to close - now, the rotor also comes to a standstill and, at the same time, the steering cylinder is in the required position. Centering spring (4) brings and holds the spool and sleeve in a neutral position to each other. ressure relief valve (5) limits the system pressure of the steering circuit. On the oad-sensing variants, the pilot valve for the load signal is installed instead (see sectional drawing). wo shock valves (6) protect ports and to the steering cylinder. If one of the shock valve responds, the discharged oil is fed via anti-cavitation valve (7) to the opposite side, or missing leak-oil aspired from the tank. In the event of an oil supply failure, the AGC operates as hand pump. In this operational state, oil can be withdrawn from the tank via anti-cavitation valve (8), with check valve (9) preventing air to be aspired via the pump port (). During normal operation, this valve prevents shocks on the steering wheel caused by excessive external steering forces ilot spool 2 Control sleeve 3 otor set 4 Centering spring 5 ressure relief valve 6 Shock valve 7 Anti-cavitation valve 8 Anti-cavitation valve 9 Check valve

4 4/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 Device variants Standard variant Open Center with Non eaction = OC / N Mainly used in steering systems with fixed displacement hydraulic pumps. When no steering movement is performed, the connection between pump port () and tank port () is open (OC), and the pump flow is directed to the tank almost at zero pressure. orts 1) (left) and 1) (right) are blocked in the neutral position. In this way, external forces acting via the steering cylinder are supported without the driver perceiving any resulting reaction forces on the steering wheel (Non eaction). 1) Contrary to standardization, the actuator lines in steering systems are usually designated and, not A and B. Standard variant Open Center with eaction = OC / In the neutral position, the cylinder ports are connected with each other. External forces acting via the steering cylinder are perceived as reaction force by the driver on the steering wheel (eaction). When the driver releases the steering wheel after the steering maneuver is completed, the wheels and the steering wheel automatically return to straight-ahead travel, provided that the steering geometry is suitable for this. oad-sensing variants Steering units with oad Sensing provide a load signal that can be used for controlling a priority valve and/or a pump. hey are designed as Closed-Center steering systems, with the connection of pump port () to tank port () being closed in the neutral position. If the steering system and working hydraulics are supplied by a common pump, a priority valve must be installed. his valve ensures the preferred supply of the steering unit with oil, with the valve being controlled by the load signal of the steering unit. If no steering movement is performed, the entire oil flow from the pump is available to the working hydraulics. Fixed or variable displacement pumps can be used as hydraulic pump. D D

5 E 14365/ AGC Hydraulics Bosch exroth AG 5/12 Device variants oad signal, dynamic he oil flowing in the load signal line transmits the load signal, with the pilot oil flowing from the priority valve to the steering unit. Also in the neutral position, a continuous, low pilot oil flow of ca. 0.5 l/min is provided. Consequently, the steering unit has approximately the same temperature as the oil. hermal shocks are largely prevented. he D variant causes the priority valve to react faster. he hard point at the beginning of the steering movement is usually no longer perceivable- even under cold start conditions. Flanged-on priority valve Steering units with flanged-on priority valve significantly reduce the piping effort. ow-noise variant Steering units of the AGC Open Center variant are generally delivered in the low-noise variant N. Functions in the steering circuit D D AGC of D variant for flanged-on priority valve Servo-operation Steering units of type AGC consist of a manually operated servo-valve of rotary spool design, a rotor set, which operates according to the gerotor principle, and the required valves for the steering circuit. he frame size of the rotor set determines the oil volume, which flows per steering wheel turn to the steering cylinder. he frame size of the rotor set is selected so that with 3 to 5 turns of the steering wheel, it is possible to steer from one limit stop to the other. Emergency operation During normal operation of the steering unit, when the hydraulic oil displaces a sufficient amount of oil, the torque on the steering wheel is less than 5 Nm. In the event of a hydraulic pump failure, the steering unit operates in the emergency mode; the rotor set acts as hand pump, and the vehicle is steered manually, without power assistance. he pressure that can be generated manually depends on the frame size of the rotor set and the force applied to the steering wheel. he smaller the rotor set, the higher the pressure that can be built up manually. During manual steering, the following pressures can be achieved in dependence upon the steering moment: M steer Frame size Nm p in bar Nm p in bar M steer Frame size Nm p in bar Nm p in bar If a higher pressure is required for steering in emergency operation at 70 Nm, a steering unit with reduction gear, AGU to E or AGZ to E 11868, can be installed. ressure relief valve he pressure relief valve is available with three settings: 90 bar; 140 bar; 175 bar Note! he pressure in the -line adds to the set pressure. Shock and anti-cavitation valves hese valves, which are installed in the AGC on the cylinder side, are available with three settings: 150 bar; 200 bar; 240 bar Anti-cavitation valve In the event of a hydraulic pump failure, this valve, which is installed between the and the port, re-aspires hydraulic fluid from the tank. Check valve his valve, which is installed in the port prevents: oil from returning from the steering cylinder into the hydraulic system when the cylinder pressure becomes higher than the system pressure due to travel obstructions. Steering shocks onto the steering wheel are therefore largely suppressed. air from being aspired via the port in emergency operation. Attention! Emergency operation is not intended for continuous operation!

6 6/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 echnical data (for applications outside these parameters, please consult us!) General Nominal pressure p bar 175 Ambient temperature range ϑ C 20 to +80 Hydraulic fluid see below Hydraulic fluid temperature range ϑ C 20 to +80 Viscosity range ν mm 2 /s 10 to 800 ermissible maximum degree of contamination of the hydraulic fluid Cleanliness class to ISO 4406 (c) Class 19/16/13 1) Steering moment - standard 2) M Nm 5 Steering moment - emergency operation M Nm 160 permissible Max. tightening torque for mounting screws M Nm 30 - see E Steering column 1) he cleanliness classes specified for components must be adhered to in hydraulic systems. Effective filtration prevents malfunction and, at the same time, prolongs the service life of components. For the selection of filters, see data sheets E 50070, E 50076, E 50081, E 50086, E and E ) Other steering moment variants (e.g. low ) on request

7 E 14365/ AGC Hydraulics Bosch exroth AG 7/12 echnical data of the hydraulic fluid Hydraulic fluids Before carrying out engineering, please refer to the extensive information on the selection of hydraulic fluids and operating conditions in our data sheets E (mineral oil) and E (environmentally friendly hydraulic fluids). hese data sheets refer to axial piston units, but can also be applied by analogy to steering units. In the case of hydraulic fluids, which require FM seals, please consult us. Operating viscosity We recommend that the operating viscosity (at operating temperature) be selected within the range of ν opt = optimum operating viscosity range of 16 to 46 mm 2 /s referred to temperature, which is optimal in terms of efficiency and service life. imiting viscosity For limiting conditions, the following values are valid: ν min = 10 mm 2 /s at a permissible max. temperature of ϑ max = 80 C ν max = 800 mm 2 /s emperature range: (cf. selection diagram) ϑ min = 20 C ϑ max = 80 C If temperature differences of more than 20 C between the steering unit and the hydraulic fluid are to be expected, either a D or DA variant or an Open-Center variant should be installed to warm up the steering unit. Explanation regarding the selection of the hydraulic fluid For the selection of the right hydraulic fluid, the operating temperature and the ambient temperature must be known. he hydraulic fluid should be selected so that the operating viscosity ν opt is within the optimum range at operating temperature (see selection diagram). We recommend that the next higher viscosity class be selected. Example: At an ambient temperature of X C, the tank temperature reaches 60 C. Within the optimum viscosity range, this corresponds to viscosity classes VG 46 or VG 68; the class to be selected is: VG 68. Filtration of the hydraulic fluid he finer the filtration, the better the cleanliness class achieved for the hydraulic fluid, and the longer the service life of the complete hydraulic system. Note! o ensure functional reliabilty of the steering unit, at least the cleanliness classes specified for the hydraulic fluid are required. Selection diagram Visicosity in mm 2 /s VG 22 VG 32 VG 46 VG 68 VG ν opt. 5 5 emperature Hydraulic fluid temperature range

8 l 8/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 echnical data, hydraulic Steering unit ype Displacement cm3 Nom 1) l/min Flow max. 2) l/min ermissible max. pressure in port bar bar and bar AGC AGC AGC AGC AGC AGC AGC AGC AGC AGC AGC AGC ) eferred to a steering velocity of 100 steering turns /min. 2) Max. flow for the variant Open Center, low noise, series 1X = 40 l/min (values for Standard centering spring package) Calculation of the steering moment Steering moment 1 b M = 0.05 F A [Nm] 1+ e b Steering force F = M I 10 3 [N] h b M Formula symbols A = required cylinder area [mm 2 ] A 1 = cylinder piston area, single-rod cylinder [mm 2 ] A 2 = annulus cylinder area, single-rod cylinder [mm 2 ] b = tire width [mm] d = piston rod diameter [mm] D = cylinder diameter [mm] e = distance swivel bearing - center of tire [mm] F = steering force [N] F A = steering axle load [N] h = cylinder stroke length [mm] i = number of steering wheel turns e l = smallest, effective steering leverage [mm] M = steering moment [Nm] n = steering speed [min 1 ] n idle = motor idling speed [min 1 ] n motor = operating speed of motor [min 1 ] p = steering pressure [bar] q vp = pump flow [l/min] V = displacement of steering unit [cm 3 /rev] V = displacement of steering pump [cm 3 /rev] V CY = cylinder volume [cm 3 ] μ = friction coefficient

9 E 14365/ AGC Hydraulics Bosch exroth AG 9/12 Dimensioning of steering cylinder and steering pump Steering cylinder equired cylinder area Cylinder area (piston side) Cylinder area (piston rod side) A = F 10 p A 1 = π D 2 4 A 2 = π (D 2 d 2 ) 4 [mm 2 ] [mm 2 ] [mm 2 ] If a single-rod cylinder or a double-rod cylinder are used, A 2 must be greater than the required cylinder area. If two cross-connected single-rod cylinders are used, A 1 +A 2 must be greater than the required cylinder area. he frame size of the steering unit is calculated from the cylinder volume and the desired number of steering wheel turns. Cylinder volume Steering pump he pump should be dimensioned so that at idling speed of the motor, a steering speed of approx. 50 min 1 can be achieved. Depending on the steering wheel diameter, the maximum steering speed is ca. 100 to 150 min 1. ump flow q V = V (n +10) 10 3 l/min. he pump displacement ( frame size) required for steering at idling speed and at operating speed of the vehicle must be calculated. Frame size of the pump at idling speed V = q V 103 n idle [cm 3 /rev] A h V ZY = [cm 3 ] 10 3 Displacement AGC Frame size of the pump at operating speed V = q V 103 n Motor [cm 3 /rev] V = V ZY i [cm 3 /rev] he usual number of steering wheel turns is 3 to 5 from limit stop to limit stop. Note! Further information on suitable steering columns can be found in E 11874, and on associated priority valves for steering systems in load signal circuits in E For general information, see E B1. roduct-specific instructions in E B2.

10 10/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 Unit dimensions: ype AGC... / AGC...D... (dimensions in mm) 63 ±0,5 34 ±0,5 D Gear hub profile 16/32 Diametral pitch to ANS B ,3 30 ±1 2,8 M10; min. 44 l 1 1) l Frame size l 1 l Imperial, metric thread M10; 16 3/8-16 UNC; 16 2) Ød 4 d ) D bore on variant AGC...D... 2) Only with variant 12 (see pipe ports) b a 1 ort Variant d 1 Ød 2 Ød 4 b min. a 1 a 2 α 01 G 1/ max. 0.2,,, 06 M18x max ±1 12 3/4-16 UNF max ±1 40 M18x max G 1/ ±0.5 D 06 M12x ± ±1 12 7/16-20 UNF ± ±1 40 M12x ±0.5 Note! Variants AGC...DA.. are not covered by this table. For more details, see page 11. UNF, metric - thread d 4 d 2 d 1 α b a 1 a 2

11 E 14365/ AGC Hydraulics Bosch exroth AG 11/12 Unit dimensions: ype AGC...DA.. (dimensions in mm) Ø44,4 Gear hub 16/32 Diametral pitch to ANS B ±1 6,3 2,8 M10; Ø25,4 15 min. l 1 l 2 44 D Ø88 +3 Ø82 ±0,3 Frame size l 1 l M10; 16 Metric thread Ød 4 d 1 ort Variant d 1 Ød 2 Ød 4 b min. a 1,,, 40 M18x b a 1

12 12/12 Bosch exroth AG Hydraulics AGC E 14365/10.07 Notes Bosch exroth AG Hydraulics Zum Eisengießer ohr am Main, Germany hone +49 (0) / 18-0 Fax +49 (0) / documentation@boschrexroth.de Bosch exroth AG Mobile Hydraulics D archim udwigsluster Chaussee 5 hone / Fax / oder his document, as well as the data, specifications and other information set forth in it, are the exclusive property of Bosch exroth AG. It may not be reproduced or given to third parties without its consent. he data specified above only serve to describe the product. No statements concerning a certain condition or suitability for a certain application can be derived from our information. he information given does not release the user from the obligation of own judgment and verification. It must be remembered that our products are subject to a natural process of wear and aging.