Double Portion Industries (M) Sdn Bhd

No 39, Jalan 5/C, Pusat Perindustrian Sungai Chua,
43000 Kajang, Selangor,

Phone: +60 3 8733 6258
Fax: +60 3 8733 7258


SR Engineering

HI-Lock Unit Series


Hi-Lock Variations Perfectly Satisfy Your Stringent Requirements.

HU Hi-Lock Unit | HMS Power Units | VF Valve Units | M-301 Valves Unit
  • Hi-Lock Units are best suited to the system that performs hydraulic locking.
  • Maintenance-free, simple and easy control: no need for complicated control as required in power-driven pumps.
  • Air-driven pumps: realizing energy saving and explosion proof.
  • Lower costs, compactness, great economy, and small space.
  • Perfect safety measures. Dependable with pressure-detecting PS that immediately detects irregularity.

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SR Air Driven Hydraulic Pumps Series

To Hydraulic Pressure from Air Pressure! Easy! Simple! Compact!

There series of a rich variation, a total of 15 models. Further highly efficient-ization is realized by full model change!

SR040 | SR063 | SR100 Series

SR hydraulic pump series are air-over-hydraulic pumps operated with compressed air. Pump's discharge pressure is controlled by operating air pressure. Oil flow rate increases at the low hydraulic pressure and decreases at the high hydraulic pressure.

When air pressure is balanced with hydraulic pressure, the pump stops automatically, and will start automatically when hydraulic pressure decreases. The pump, then, operates continuously until air pressure reaches equilibrium with hydraulic pressure.

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Directional Control Valves

This valve is a 2-position 3-port valve which changes over the flow passage of oil by an air pilot signal. This is a valve special for installation to the manifold employing a HU high lock unit and a VF valve unit.

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Pressure Switches

1. Because of the wide pressure from low to high pressure, this switch can be used to meet the wide range of the specifications.

2. With the robust body construction against strong vibration, piping and wiring will be installed safely with conduit.

3. Sensing part reduces pressure differential up to 20% (compare with our product) by using newly developed lever mechanism.

4. It is possible to select from 2 types. - Sub-plate mount (EF-type) and - Tapped body type (ET-type)

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Can't find what you need? We carry many types of SR Engineering products, we welcome your enquiries.
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