先导式, 减压/溢流主级 带集成T-8A控制插孔, 钻入式阻尼, 和 口4外泄

流量: 10 gpm40 L/min. | 插孔: T-21A
技术特性 [ + ]

此类阀为3口,外泄,带集成先导级控制插孔的常开调节元件。先导级控制插孔可接受任何T-8A插孔的压力控制插装阀。减压阀将进口(口2)高压主油路压力调节减至口1所需的减压压力,同时具备从口1到油箱(口 3)的全流量溢流功能。先导级控制阀的设定决定了减压口(口1)与外泄口(口4)之间的压力降。

  • 此类阀主级阻尼孔是直接钻在活塞上而不是嵌入进去。这使阀能够工作在高强度需求的应用中。
  • 口3处最大压力不能超过3000 psi (210 bar)。
  • 先导式操作阀在减压与溢流模式间过渡时具有极低的死区。
  • 口4处最大压力不能超过5000 psi (350 bar)。
  • 先导式操作阀具有非常平坦的压力/流量特性,良好的稳定性和极低的滞回。
  • 外泄口(口4)处的压力直接以1:1的比例增加到阀的设定值上,且压力不能超出5000 psi(350 bar)。
  • 最大进口压力由偏置弹簧决定。D范围弹簧由2000 psi (140 bar)最大压力降测试,W范围弹簧由5000 psi (350 bar)最大进口压力测试。
  • 注意:带-8控制选项,应首先用正确的扭矩安装主级阀。然后用合适的扭矩将T-8A先导级控制阀安装进主级阀中。
  • -8控制类型允许通过T-8A插孔将先导级控制阀直接旋进溢流阀的顶部。这些先导级控制阀需单独采购并包括电比例,电磁,气控先导,液控先导操作。请参照先导级控制阀。
  • 从减压压力口(口1)到进口(口2)的反向液流可能导致主阀芯关闭。如果油路中需要反向自由流,可以考虑在油路中加入单向阀。
  • 利用Sun浮动结构减少由于过量安装扭矩或插孔/插装阀加工误差带来的内部零件粘结的可能性。
技术数据 [ + ]
注意:技术参数可能因产品配置而不同。请查看产品配置部分。
插孔 T-21A
系列 1
通流能力 10 gpm40 L/min.
最大操作压力 5000 psi350 bar
控制先导流量 7 - 10 in³/min.0,11 - 0,16 L/min.
先导控制孔型 T-8AT-8A
阀头部安装六角尺寸 7/8 in.22,2 mm
阀安装扭矩 30 - 35 lbf ft41 - 47 Nm
型号重量 .30 lb0,15 kg
Seal kit - Cartridge Buna: 990021007
Seal kit - Cartridge Polyurethane: 990021002
Seal kit - Cartridge Viton: 990021006
常见问题 [ + ]

设置压力的误差在产品的性能参数页中都有详细说明,您可以通过点击可选产品网页中的更多产品信息到达产品性能参数页面。

Yes. If you look in the sandwich section you will see that we offer many such packages. When you are pressurizing B, A is connected to tank, allowing the reducer to do its job. When you reverse, the drain or tank port of the reducer is pressurized by A. This increases the setting of the reducer and helps keep the reducer open in the reverse flow direction.

Our reducing valves are outside-in valves; the supply pressure on the outside of the working parts is higher than the inside. At some pressure differential, the outside (sleeve) will close in on the piston and cause the valve to stick. A D range is adjustable from 25 to 800 psi with a maximum differential of 2000 psi. This means you could set the valve at 600 psi and expect it to work correctly with a supply pressure of 2600 psi. The valve may work at higher differentials, but we do not recommend it. The W and C ranges are tested over their entire range with an inlet pressure of 5000 psi. All direct-acting valves are tested with an inlet pressure of 5000 psi.

No. A reducing/relieving valve throttles a supply of oil to maintain a set pressure in a secondary circuit. The valve is open until the secondary or downstream pressure rises to the setting of the valve at which time it starts to close to limit the pressure. If the secondary or downstream pressure is caused to go above the setting, the valve shifts into relieving mode and throttles the secondary circuit back to tank to prevent over-pressure. At no time can the valve connect the supply to tank.

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

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.

Yes. A reducing or reducing/relieving valve is normally open. If the pressure in the secondary circuit is less than the setting, it will be open.

2 caveats: (1) If the valve is in the reducing mode and you suddenly reverse the flow, the valve will not have time to open and will shift into relieving mode or (2) If the back flow generates a pressure drop through the valve that exceeds the setting, the valve will shift into the relieving mode.

When in doubt, use a reverse flow check.

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.
额外来源 [ + ]