常开, 平衡锥阀, 逻辑单元 - 外接口关闭

流量: 15 gpm60 L/min. | 插孔: T-21A
DODR : 常开, 平衡锥阀, 逻辑单元 - 外接口关闭
技术特性 [ + ]

此阀为常开,平衡锥阀结构,开关单元。当外控口(口4)被阻塞,阀将处于开启位置。当口4导通到油箱且口3有足够压力时,阀处于关闭位置。

  • 当口1和口2处压力为5000 psi (350 bar)、外控口(口4)通油箱且先导口3处达到最小先导压力400 psi (30 bar)时,独特的平衡结构将提供可预测的切换。
  • 此类阀在口1与口2间达到液压平衡。
  • 口1和口2与口3和口4之间被完全密封开。口3和口4之间也被有效密封着。
  • 口1和口2之间的泄漏速率非常低,通常来说在5000psi时,泄漏速率小于10滴/分钟(即在350bar时,小于0,7 cc/min)
  • 口4可以外部直接连接到一个先导级切换阀。先导级阀的泄漏速率应该低于10滴/分钟,且须能满足先导流量需求。Sun的先导级电磁阀DAA*-*** 是这个应用的理想选择。
  • 当先导压力降到145 psi(10 bar)以下,阀将打开。
  • 所有端口都可以接受5000 psi (350 bar)的压力。
  • 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 15 gpm60 L/min.
最大操作压力 5000 psi350 bar
切换阀所需最小先导压力 400 psi28 bar
控制先导流量 See Performance DataSee Performance Data
110 SUS (24 cSt)下的最大泄漏 10 drops/min.@5000 psi0,7 cc/min.@350 bar
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 .35 lb0,15 kg
Seal kit - Cartridge Buna: 990021007
Seal kit - Cartridge Polyurethane: 990021002
Seal kit - Cartridge Viton: 990021006
性能曲线 [ + ]
常见问题 [ + ]

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.

Because of the very high ratio, the COFO has limited capacity. The discharge path is across a .050 inch (1,3 mm) diameter orifice. If you have large accumulators combined with low precharge pressures, this may not discharge the energy quickly enough. Using the COFO XDN cartridge in conjunction with an LODA XDN will provide capacity for larger applications.

The LH*A family of valves has been optimized to be used in a package to provide a power source for hydraulic tools. We can quantify the performance of the valve in static conditions but we cannot tell you how it will do in your application.

For instance: You want to use the valve as a compensator for a load-sense power steering package. When you are steering the machine and raising an implement, the valve is in a bypass mode (throttling on the bypass side). When the implement actuator bottoms out, pressure jumps to maximum and now the valve needs to change to the restrictive mode. Since the LH*A is balanced against pressure on the bypass side the only thing moving the spool is its own spring. The time this takes is dependent on where the spool was to begin with and where it has to go.

During this transition the steering will see the pressure differential across it suddenly change from about 150 psi (10 bar) to a system pressure of say 3000 psi (200 bar) and suddenly back down to about 150 psi (10 bar). When this scenario was described to me it was termed the broken thumb syndrome.

Sun does not and cannot provide technical support for this type of application. The valve has been successfully used in similar applications. What is necessary to make it work is up to whoever is doing the application.

The valve was developed originally to power demolition hammers.  The hammers are aftermarket accessories that are mounted on a large variety of excavators.  The "hammer" circuit provides a method of tapping into the existing hydraulic system of the excavator, turning the tool on and off, controlling flow, and limiting pressure.

FAQ hammer valve schematic

Every manufacturer of hammers has very specific needs as far as flow and pressure and there is a large disparity of hydraulic systems in the excavators. For this reason, Sun has never had a catalog package for this circuit.

Sun does not and cannot provide technical support for "hammer valve" installations.

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 [ + ]