Anti-Shock, pilot-operated, balanced poppet sequence valve with drain to port 3

Capacity: 30 gpm120 L/min. | Cavity: T-2A
SDFT : Anti-Shock, pilot-operated, balanced poppet sequence valve with drain to port 3
Technical Features [ + ]

Pilot-operated, anti shock sequence cartridges limit maximum system pressure and also limit the rate of pressure rise. The valve opens and then ramps closed at a constant speed, independent of settings and flows. The adjust screw determines the maximum (relief) setting and the minimum (threshold) setting.

The external drain makes the valve insensitive to pressure at port 2.

  • Because the modulating occurs inside the cartridge, these valves are immune to most of the problems associated with cavitation, namely noise and manifold erosion.
  • Pilot flow continues to increase as the pressure at port 1 (inlet), relative to the pressure at port 3 (drain), rises above the valve setting.
  • Not suitable for sequncing cylinders.
  • Pressure at port 3 is directly additive to the valve setting at a 1:1 ratio and should not exceed 5000 psi (350 bar).
  • Pressure settings are insensitive to back pressure at port 2.
  • Will accept maximum pressure at port 2; suitable for use in cross port relief circuits.
  • Valve is relatively insensitive to varying oil temperatures and oil borne contamination.
  • Not suitable for use in load holding applications.
  • When pressure at the inlet (port 1) exceeds the threshold setting, the valve opens to tank (port 2). The pilot section moves forward at a steady rate, increasing the setting by compressing the pilot spring. Maximum setting is achieved when the pilot section reaches a mechanical stop.
  • The main stage orifice is protected against contamination.
  • Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge machining variations.
Technical Data [ + ]
Note: Data may vary by configuration. See CONFIGURATION section.
Cavity T-2A
Series 2
Capacity 30 gpm120 L/min.
Factory Pressure Settings Established at 4 gpm15 L/min.
Maximum Operating Pressure 5000 psi350 bar
Control Pilot Flow 10 - 25 in³/min.0,16 - 0,41 L/min.
Pressure Ramp Up Time 200 - 400 ms200 - 400 ms
Response Time - Typical 2 ms2 ms
Adjustment - No. of CW Turns from Min. to Max. setting 4.54.5
Valve Hex Size 1 1/8 in.28,6 mm
Valve Installation Torque 45 - 50 lbf ft61 - 68 Nm
Adjustment Screw Internal Hex Size 5/32 in.4 mm
Locknut Hex Size 9/16 in.15 mm
Locknut Torque 80 - 90 lbf in.9 - 10 Nm
Seal kit - Cartridge Buna: 990402007
Seal kit - Cartridge Polyurethane: 990002002
Seal kit - Cartridge Viton: 990402006
Performance Curves [ + ]
FAQs [ + ]

A sequence valve opens when the pressure at port 1 exceeds the setting of the valve. When pressures at port 1 and port 2 both exceed the setting of the valve the valve goes full open, or sequences. When this happens flow can go in either direction, just so long as port 1 stays above the setting.

Pressure setting tolerances are listed in our Performance Data page. A link to this page can also be found in the Additional Resources tab of the applicable product page.

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

Only external seals are serviceable.  Sun offers replacement seal kits for all cartridge models. The applicable kit part number can be found in the product page's Technical Data table or by using our Cartridge Seal Kit search function located under Accessories. Please note: Converting the external seals from one material to another does not ensure fluid compatibility with that material due to the existence of internal seals within the cartridge.
Additional Resources [ + ]