Priority valve Type LPS

Transcription

1 RE /10.98 riority valve Type LS Nominal sizes 40 to 160 Series 1X Nominal pressure 250 bar Maximum flow 160 L/min. H/AD/5977/98 riority valve type LS... Contents Description age Features 1 Ordering details 2 Function, section 3 Versions, symbols 4 Technical data 5 Unit dimensions 6 to 9 Features The LS priority valve is used in conjunction with steering units using load sensing. The priority valves guarantee the priority supply of steering circuits, before all other actuators, with pressure fluid as defined in the statuatory regulations. The priority supply of the steering circuit is pressure independent. ressure fluid that is not required for steering is returned to tank or is made available to other actuators For the supply of steering and work hydraulics only a pump is required. With the aid of priority valves it is possible in conjunction with variable displacement pumps to create energy saving hydraulic systems. riority valves can be used in combination with other valves, e.g. sequence valves, flow dividers or pressure reducing valves. LS 1/10

2 Ordering details L S 1X / LD / * riorty valve Design Standard = S = Special specifications leasse clarify with our sales organisation Nominal size L/min A 1) 1) R 1) 40 = = = = 160 Connection type Flangeable ump mounting Line mounting Series Series 10 to 19 (10 to 19: unchanged installation and connection dimensions) Load sensing Dynamic load signal = A = = R = 1X = LD ipe connections 01 = ipe thread to DIN = Metric ISO thread to DIN = UNF thread to SAE 2; 3) LD damping orifice 2 = 1.0 mm 3 = 1.5 mm 2) LD dynamic orifice 4 = 0.8 mm 6 = 1.0 mm 2) damping orifice 4 = 0.8 mm 6 = 1.0 mm Control pressure differential Bar A 1) 1) R 1) 4 = 4 7 = 7 10 = 10 = Standard programme = Expanded programme 1) Connection type 2) When testing the machine, the system can be optimised by changing the orifices 3) lease take note! The LD dampling orifice has to be larger than the LD dynamic orifice Ordering examples: LS 80 R1X/LD7-463/01 riority valve; line mounting; nominal size 80; Dynamic load signal; control pressure differential 7 bar; Orifice combinations 0.8/1.0/1.5; ipe connections: with pipe thread LS 160 R1X/LD10-463/01 riority valve; line mounting; nominal size 160; Dynamic load signal; control pressure differential 10 bar; Orifice combinations 0.8/1.0/1.5; ipe connections: with pipe thread Rexroth Hydraulics 2/10 LS

3 Function, section The type LS priority valves are used in conjunction with steering systems of closed centre-load sensing design. They distribute the pump flow between the steering and work hydraulics, however the steering supply has priority. In conjunction with variable displacement pumps it is possible to create energy saving hydraulic systems. The priority valve works in the same way as a 3-way flow control valve. The controlled flow (CF) is made available to the steering and the remaining flow (EF) is passed to the work hydraulics. The measurement orifice A 2 in this system is not to be found in the flow control valve, but in the steering control valve. It is closed in the neutral position and is opened with regard to the flow demands. The load signal is sensed behind the measurement orifice. In the neutral position the load signal line is connected to tank. As with a 3-way flow control valve the priority valve, by controlling the flow at the control orifice A 1, controls the pressure differential at the measurement orifice A 2 and thereby acheivies a balanced condition between the forces acting on the control spool. The required pressure independent supply to the steering is thereby guaranteed. The type LS priority valve works independently of the steering pressure and of the work hydraulics pressure. This is acheived via a second control orifice A 3. It moves into its working position when the pressure in the work hydraulics is higher than the steering pressure. 3 A 1 A CF = ump CF = Steering (control flow) EF = Work hydraulics (excess flow) = Control orifice A 1 A 2 A 3 = Measurement orifice = Control orifice LD 1 = LD dynamic orifice 2 = LD damping orifice 3 = damping orifice EF A LD EF CF LS 3/10 Rexroth Hydraulics

4 Versions, symbols Standard version - flangeable The LS..A.. priority valve is directly flanged onto the steering unit. Both components result in a compact unit. No piping is required between the priority valve and the steering unit. This design is available with the nominal flows of 40 and 80 L/min. It is suitable for steering units up to 200 cm 3 /U. The pilot control valve for limiting the steering pressure is contained within the steering unit. Symbol LS..A.. L CF T LD R L EF T R Standard version - line mounting and pump mounting The LS..R.. priority valve is a version suitable for line mounting. These priority valves are available with the nominal flows of 40, 80, 120 and 160 L/min. When using the type LS..R.. care has to be taken to ensure that the pressure relief valve, for the load signal line, is integrated into the steering unit. If a LS..R.. is used in conjunction with a steering unit without a pressure relief valve, then the load signal lines have to be externally protected. The LS... version is designed to be directly mounted onto a gear pump. 40 and 80 L/min versions are available. Load signal dynamic Symbol LS..R..; LS... CF EF LD = ump CF = Steering EF = Work hydraulics T = Tank LD = Load signal (dynamic) R; L = Cylinder Via the LD dynamic orifice a continuous small flow is passed into the load signal lines from the CF pressure connection. It is, therefore guaranteed that the load signal lines are always full. This leads to the priority valve having short reaction times. The dynamic orifice also takes over the task of unloading the CF connection for the case of when the steering does not accept any oil flow and the other actuators are being operated with high pressure. Rexroth Hydraulics 4/10 LS

5 Technical data, general Nominal pressure p bar 250 eak pressure orts, EF p max. bar 250 orts CF, LD, R, L p max. bar 175 Ambient temperature range ϑ C 20 to +80 ressure fluid see below ressure fluid temperature range ϑ C 20 to +80 RE /10.98 Viscosity range ν mm 2 /s 10 to 800 Degree of contamination Maximum permissible degree of fluid contamination is to ISO 4406 class 19/15. We, therefore, recommend a filter with a minimum retention rate of β to ISO 4572 ressure fluid technical data ressure fluids Before selecting a pressure fluid please refer to the extensive information regarding pressure fluid selection and application conditions in our catatlogue sheets RE (mineral oil) and RE (environmentally compatible fluids). These catalogue sheets refer to axial piston units, the details can however be analogously applied to the steering units. For pressure fluids that require FKM seals please contact ourselves. Operating viscosity We recommend that the operating viscosity (at operating temperature) for efficiency and service life, is selected within the optimum range of ν opt = optimum operating viscosity range 16 to 46 mm 2 /s with reference to the temperature. Limiting viscosity For the limiting conditions the following values apply: ν min = 10 mm 2 /s at maximum permissible temperature of ϑ max = 80 C ν max = 800 mm 2 /s ressure fluid temperature range (see selection diagram) ϑ min = 20 C ϑ max = 80 C Further on the selection of pressure fluids A prerequisite to being able to select the correct pressure fluid is knowing the operating temperature and the ambient temperature. The pressure fluid should be so selected that the operating viscosity at the working temperature lies within the optimum range (see selection diagram). We recommend that the next higher viscosity class is selected. Example: For an ambient temperature of X C the tank temperature stabilises at 60 C. To achieve the optimum viscosity, this relates to the viscosity clases of VG 46 or VG 68; should be selected: VG 68. ressure fluid filtration The finer the filtration the higher the cleanliness class of the pressure fluid is achieved and so the higher the service life of the entire hydraulic system. To ensure the functionability of the steering pump a minimum pressure fluid cleanliness class 19/15 to ISO 4406 is necessary. Selection diagaram º 20º Viscosity range VG 22 0º 20º 40º 60º 80º 100º VG 32 VG 68 VG 46 VG º 25º 10º 0º 10º 30º 50º 70º 90º 115º ressure fluid Temperature ϑ in C ϑ min = 40 C temperature range ϑ max = 115 C 46 ν opt 16 LS 5/10 Rexroth Hydraulics

6 Unit dimensions: type LS..A.., NS 40 and 80 (Dimensions in mm) EF R L T = ump ,5 Z 1 T = Tank EF = Work hydraulics R, L = Cylinder 1 4 off O-ring 24x2 1) 2 O-ring 6x2 1) 3 Valve fixing screws M10x40 1) DIN ; M A = 70 Nm ) Included within the scope of supply View Z 2 Thread type NS ort Version d 1 +0,4 b min. ±0,5 Inch, metric - threads 90, EF 01 G 1/ , M22x d 1 T, L, R 01 G 3/ b 02 M18x Rexroth Hydraulics 6/10 LS

7 Unit dimensions: type LS..., NS 40 and 80 (Dimensions in mm) 53,5 Ø11 24,7 Ø6,5 35,5 1 24, LD ,5 Z 38 = ump CF = Steering EF = Work hydraulics EF CF LD = Load signal View Z 1 O-ring 20x2.5 (included within the scope of supply) Inch - threads Thread type NS ort Version d 1 +0,4 b min ±0,5 90 d 1 40, 80 EF, CF 01 G 1/ b LD 01 G 1/4 12 LS 7/10 Rexroth Hydraulics

8 Unit dimensions: type LS..R.., NS 40, 80 and 120 (Dimensions in mm) 31 35,2 Ø 9 80,5 LD 40,5 Ø ,7 Z 40 = ump CF = Steering EF = Work hydraulics LD = Load signal EF CF View Z Thread type NS ort Version d 1 +0,13 Ø d 2 +0,4 b min ±0,4 a 2 α ±1 01 G 1/ , EF 02 M22x /8-14 UNF G 1/ ; 80 CF 02 M22x /4-16 UNF G 1/4 12 LD 02 M12x /16-20 UNF G 3/ , EF 02 M27x /16-12 UN G 1/ CF 02 M18x /4-16 UNF G 1/4 12 LD 02 M12x /16-20 UNF ,2 0,2 0,2 0,2 α UNF - threads Ø d 2 d 1 b a 2 45 Inch, metric - threads 90 d 1 b Rexroth Hydraulics 8/10 LS

9 Unit dimensions: type LS..R.., NS 160 (Dimensions in mm) EF CF 69,5 131,5 123,5 LD 62,5 Ø ,5 = ump CF = Steering EF = Work hydraulics LD = Load signal Thread type NS ort Version d 1 +0,4 b min +1 Inch, metric - threads 01 G , EF 02 M33x G 1/ CF 02 M22x G 1/4 12 LD 02 M12x b 90 d 1 LS 9/10 Rexroth Hydraulics

10 Notes Mannesmann Rexroth AG Rexroth Hydraulics D Lohr am Main Jahnstraße 3-5 D Lohr am Main Telefon / 18-0 Telefax / Telex Rexroth Hydraulik archim D archim Ludwigsluster Chaussee 5 Telefon / Telefax / oder The specified data is for product description purposes only and may not be deemed to be guaranteed unless expressly confirmed in the contract. All rights reserved Subject to revision 10/10 LS

11 Notes Mannesmann Rexroth AG Rexroth Hydraulics D Lohr am Main Jahnstraße 3-5 D Lohr am Main Telefon / 18-0 Telefax / Telex Rexroth Hydraulik archim D archim Ludwigsluster Chaussee 5 Telefon / Telefax / oder The specified data is for product description purposes only and may not be deemed to be guaranteed unless expressly confirmed in the contract. LS 11/10 All rights reserved Subject to revision

12 Notes Mannesmann Rexroth AG Rexroth Hydraulics D Lohr am Main Jahnstraße 3-5 D Lohr am Main Telefon / 18-0 Telefax / Telex Rexroth Hydraulik archim D archim Ludwigsluster Chaussee 5 Telefon / Telefax / oder The specified data is for product description purposes only and may not be deemed to be guaranteed unless expressly confirmed in the contract. All rights reserved Subject to revision 12/10 LS