Flow divider-combiner assembly

Function

Function for YGDA
Port Designators [ + ]
Modifiers Ports
C, C/S Port AB: 1/2" NPTF; Ports A1, A2, B1, B2: 3/8" NPTF; Mounting Holes: .375 - 16UNC x .62 DP;
K, K/S Port AB: SAE 10; Ports A1, A2, B1, B2: SAE 8; Mounting Holes: .375 - 16UNC x .62 DP;
V, V/S Port AB: 1/2" BSPP; Ports A1, A2, B1, B2: 3/8" BSPP; Mounting Holes: M10 x 1.5-6H x .62 DP;
Technical Features [ + ]

This valve assembly uses 3 divider/combiner valves to provide 4 equal bidirectional flows. In the dividing mode, flow coming into AB is divided into 4 equal flows, A1, A2, B1, B2. In the combining mode the assembly throttles the 4 flows coming into A1, A2, B1, B2 keeping them equal.

  • Operating characteristics cause the leg of the circuit with the greatest load to receive the higher percentage of flow in dividing mode. If a rigid mechanism is used to tie actuators together, the lead actuator may pull the lagging actuator and cause it to cavitate.
  • In combining mode, compensating characteristics will cause the leg of the circuit with the lowest load to receive the higher percentage of flow. If a synchronization feature is not included, an additive accuracy error will be experienced with each full stroke of the actuator.
  • In applications involving rigid mechanisms between multiple actuators, operating inaccuracy will cause the eventual lock-up of the system. If the mechanical structure does not allow for the operating inaccuracy inherent in the valve, damage may occur.
  • In motor circuits, rigid frames or mechanisms that tie motors together, and/or complete mechanical synchronized motion of the output shaft of the motors, either by wheels to the pavement or sprockets to conveyors, will contribute to cavitation, lock-up and/or pressure intensification.
  • Variations in speed and lock-up can be attributed to differences in motor displacement, motor leakage, wheel diameter variance and friction of wheels on the driving surface.
  • Extreme pressure intensification can occur on multiple wheel drive vehicles.
  • Flow between ports is limited to spool leakage. This does not provide leak proof holding capability, but can be useful in minimizing cross flow and drift.
  • Differential slip for tractive drive systems must be achieved with orifices in the body/manifold.
  • Divisional and combining accuracy are equal.
  • Below the minimum flow rating there is not enough flow for the valve to modulate. It is effectively a tee. If flow starts at zero and rises, there will be no dividing or combining control until the flow reaches the minimum rating.
Technical Data [ + ]
Capacity 3 - 15 gpm12 - 60 L/min.
Body Type Line mountLine mount
Mounting Hole Thread .375-16 UNC - 2B in..375-16 UNC - 2B in.
Mounting Hole Depth .62 in.15,7 mm
Mounting Hole Quantity 44
FAQs [ + ]

Reasons to anodize:

  • To increase corrosion resistance. Sun uses 6061-T651 aluminum. It is one of the most corrosion resistant aluminum alloys there is. Whether or not anodizing improves the corrosion resistance of 6061 aluminum is debatable. We have yet to have a manifold returned because of corrosion.
  • Appearance (color). The 2 colors that would appeal to Sun would be blue or black. Unfortunately these are the colors that are hardest to do consistently.
  • To provide a hard wear surface. Sun does not make parts-in-body valves. The manifold is just plumbing. We don't need a wear surface.
  • Because everyone else does it. Bad reason. 

Reasons to not anodize:

  • Cost. It's another process.
  • Logistics. When you make tens of thousands of manifolds a month and you anodize hundreds, it's a problem. Consistency. See above.
  • Stamping. After a body is anodized you cannot do any more stamping without making a mess.
    Inspection. Have you ever tried to look for burrs in a black anodized body? It's the old blackboard factory at night scenario.
  • Torque. You will experience an increase in breakaway torque when removing items from an anodized manifold.
  • Fatigue life. This is the best reason to not anodize. Fatigue failure is a very complex phenomenon. What it takes to initiate a crack is difficult to predict. What it takes to propagate a crack is readily defined. Anodizing produces a very thin, very hard, and very brittle surface on aluminum. The first time you pressurize an anodized aluminum manifold you have initiated fatigue cracks. Whether or not the stress is enough to propagate the cracks is a matter of pressure and manifold geometry. Anodizing an aluminum manifold grossly reduces the fatigue life by anywhere from 20% to 50%.

Direct-acting valves are used to prevent over pressure, and pilot-operated valves are used to regulate pressure. If you are unsure, use a direct-acting valve. Sun's direct acting valves are very fast, dirt tolerant, stable, and robust. Sun's pilot-operated valves are moderately fast, they have a low pressure rise vs. flow curve, and they are easy to adjust.

There are exactly 250 Sun drops in a cubic inch or 15 in a cc.

Notes [ + ]
  • Important: Carefully consider the maximum system pressure. The pressure rating of the manifold is dependent on the manifold material, with the port type/size a secondary consideration. Manifolds constructed of aluminum are not rated for pressures higher than 3000 psi (210 bar), regardless of the port type/size specified.
Additional Resources [ + ]