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Flow Divider Series MTDA

Flow Divider Series MTDA
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Flow Divider Bi-directional Series MTDA 1/4 Reference: 100-P-000052-E-05 Issue: 07.09 These valves do not require maintenance. Flows can be split or merged with accuracy (divide/combine functions). The flow division ratio can be altered to suit customer requirements. For two hydraulic cylinders working in parallel mode exists optionally the possibility of balancing the lag at the end 1 Description 1.1 General Series MTDA units are flow dividing valves that operate automatically. They are intended for use with hydraulic fluids. They divide a flow, the total rate of which may be va- ried, into two usually equal parts. When flow passes through a valve in the opposite direction, the two part-flows are combined into one single flow (added). The dividing and combining functions are largely independent of the pressures of the two divided flows and of the fluid viscosity. If the valve has an unequal division ratio, the larger part-flow must always be through port B. In order for the valve to work properly, a continuous flow is required at all ports. For example, if one actuator is no longer able to move, then the other part-flow will also be restricted. If the two actuators served by the flow divider operate at different pressures, then the pressure of the total flow entering the valve will correspond to the higher of the two actuator pressures. Large pressure differences may give rise to significant heat generation, which must be taken into consideration when designing the system. 1.2 Application examples Work access platforms Lifting platform Harvesters Municipal equipment Snow/ice clearing equipment Wood chippers Raod rollers Tail lifts 2 Symbols A B P 3 Technical data General characteristics Description, value, unit Maximum operating pressure 315 bar Oil temperature range -20 °C ... +80 °C Viscosity range 10 mm2/s ... 300 mm2/s Filtration min. class 9 of NAS 2638 or class 20/18/14 of ISO 4406 Nitrile seals NBR

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100-P-000052-E-05 / 07.09 Flow Divider MTDA 2/4 4 Characteristic curves 4.1 Pressure drop characteristics (p) Pressure drop v. flow rate with oil viscosity of 35 mm2/s (QIn 100% = QNom) NG08 NG16 Äp (bar) NG08 15 10 5 0 0 20 40 60 80 100 QZu [%] NG16 20 4.2 Division accuracy [%] Division error v. flow rate with oil viscosity of 35 mm2/s (QIn 100% = QNom) (%) 0 20 40 60 80 NG08 NG16 4 3 2 1 0 -1 -2 -3 -4 100 QZu [%] Note: for higher division accuracy,on enquiry 1) Division accuracy ± 3 % of the maximal flow rate, based on nominal volume flow range of the respective flow divider (see example...

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100-P-000052-E-05 / 07.09 Flow Divider MTDA 3/4 6 Ordering code Flow divider Bi-directional Threaded ports Nominal size 08 16 Flow range inlet flow: Port threads M = Metric R = Inch Flow range P A + B P A + B 004-025 M18 x 1,5 M18 x 1,5 G 3/8" G 3/8" 032-100 M22 x 1,5 M18 x 1,5 G 1/2" G 3/8" 100-120 M27 x 2 M22 x 1,5 G 3/4" G 1/2" 160-250 M33 x 2 M27 x 2 G 1" G 3/4" Division ratio, see section 6.1 Variants / special features (to be inserted by the factory) M T 0 8 - 0 0 4 M 3 0 004 = 2-4 l/min 006 = 3-6 l/min 008 = 4-8 l/min 012 = 6-12 l/min 016 = 8-16 l/min 100 = 35-100 l/min 120 = 40-120...

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100-P-000052-E-05 / 07.09 Flow Divider MTDA 4/4 7 End-stop synchronisation of parallel-connected cylinders When one of the two cylinders reaches its end-stop, the flow to the other cylinder drops to approx. 5-10% of its nominal rate. This leakage flow enables the second cylinder, which has not yet reached its final position, to slowly resynchron- ise itself. To enable full-speed resynchronisation of the lag- ging cylinder, each actuator line from the flow divider must be equipped with a pressure relief valve. 8 Installation attitude and mounting To prevent the weight of the spool causing...

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