The HKC HP Series (Covering all Double Acting models: HP-035D, HP-050D, HP-063D, HP-066D, HP-075D, HP-088D, HP-100D, HP-115D, HP-125D, HP-145D, HP-160D, HP-180D, HP-200D, HP-210D and Spring Return models: HP-050S, HP-063S, HP-066S, HP-075S, HP-088S, HP-100S, HP-115S, HP-125S, HP-145S, HP-160S, HP-180S, HP-200S, HP-210S) is engineered and manufactured by HKC Co., Ltd. (South Korea). Designed with high-precision Rack & Pinion kinematics, the HP Series delivers outstanding mechanical reliability, rapid cycle response times, and exceptional fail-safe protection across modern industrial valve automation processes.

KEY PRODUCT FEATURES AND OPERATIONAL ADVANTAGES:
1. Dual Operating Configurations: Double Acting (D) and Spring Return (S):
• Double Acting (D): Uses compressed air pressure across both ports for opening and closing strokes, generating uniform, symmetrical output torque throughout the complete 90° rotation.
• Spring Return (S): Incorporates high-strength modular pre-loaded spring cartridges inside the piston chambers. In the event of an emergency air supply failure, the mechanical spring force automatically drives the valve to a predetermined safe position (Fail-Closed or Fail-Open), preventing toxic media release and plant line damage.
2. Symmetric Rack & Pinion Kinematic Design:
Twin opposed pistons move smoothly and symmetrically along the central pinion shaft, balancing internal side loads and friction. This ensures balanced torque transmission and extends service life beyond 1,000,000 continuous operating cycles.
3. Dual External Travel Stop Adjustments:
Equipped with dual stainless steel travel stop adjustment bolts located on the end caps, providing precise on-site angle adjustments of ± 5° in both open and closed positions (85° to 95°), ensuring perfect seat alignment and zero valve seat leakage.
4. Universal International Interface Standards:
• Bottom valve flange connection conforms strictly to ISO 5211 / DIN 3337 with a precision-broached double-square female shaft for direct valve mounting.
• Top pinion drive and lateral air supply ports comply fully with the NAMUR VDI/VDE 3845 standard, enabling direct, bracketless mounting of solenoid valves, limit switch boxes (APL Series), and electro-pneumatic positioners (EPL/EPR Series).
5. Rugged Hard-Anodized Aluminum Construction:
The cylinder body is extruded from premium high-grade aluminum alloy, honed to a mirror finish internally and hard-anodized for low piston drag and maximum seal life. The exterior is coated with a heavy polyester powder finish to withstand harsh offshore salt spray and industrial chemical environments.
6. Comprehensive Temperature Options & Global Safety Certifications:
Fitted with standard NBR O-rings (-20°C to +80°C) with optional high-temperature Viton/FKM seals (-20°C to +150°C) and low-temperature Silicone seals (-40°C to +80°C). Certified to international safety and quality standards including ATEX (Ex II 2GD c T6), CE, Functional Safety SIL 3 (IEC 61508), and ISO 9001.

TYPICAL INDUSTRIAL APPLICATIONS:
• Water & Wastewater Treatment: Automated butterfly valve control in intake pump stations, aeration basin valves, and sludge discharge manifolds.
• Chemical & Oil & Gas Refineries: Fast-acting ESD ball valves, flammable gas isolation, and corrosive acid/alkali distribution piping in hazardous zones.
• Food, Beverage & Pharmaceutical Processing: Sanitary stainless steel butterfly and ball valve automation in hygienic cleaning loops.
• Power Generation, Cement & Steel Mills: Cooling water isolation, flue gas ventilation damper positioning, and ash handling pipeline valves.

• Manufacturer: HKC Co., Ltd.
• Series: HP Series (Pneumatic Rack & Pinion Actuator)
• Brand Origin: South Korea
• Double Acting Models (D): HP-035D, HP-050D, HP-063D, HP-066D, HP-075D, HP-088D, HP-100D, HP-115D, HP-125D, HP-145D, HP-160D, HP-180D, HP-200D, HP-210D
• Spring Return Models (S): HP-050S, HP-063S, HP-066S, HP-075S, HP-088S, HP-100S, HP-115S, HP-125S, HP-145S, HP-160S, HP-180S, HP-200S, HP-210S
• Actuation Principle: Symmetric Rack and Pinion mechanism
• Standard Rotation: 90° (Travel adjustment range: ± 5° at both 0° and 90° positions)
• Operating Air Supply Pressure:
  - Standard Working Pressure: 2.5 bar to 8 bar (36 to 116 psi)
  - Maximum Permissible Pressure: 10 bar (145 psi)
• Operating Media: Filtered dry or lubricated compressed air (particulate size < 30 µm)
• Output Torque Capabilities:
  - Double Acting Models: From 5.5 Nm up to over 6,500 Nm (at 6 bar air supply)
  - Spring Return Models: From 4.0 Nm up to over 4,200 Nm (at 6 bar air supply)
• Construction Materials:
  - Cylinder Body: High-grade extruded Aluminium alloy, internally honed and hard anodized
  - Pistons: Die-cast Aluminium alloy
  - Pinion Shaft: Nickel-plated alloy steel or Stainless Steel (SS304/SS316)
  - End Caps: Die-cast Aluminium with polyester powder coating (Black/Blue finish)
  - Springs: High-tensile alloy steel with anti-corrosion coating, modular safety preloaded
  - O-rings / Seals:
    * Standard: NBR Rubber (Operating temperature: -20 °C to +80 °C)
    * High-Temperature Option: Viton / FKM (Operating temperature: -20 °C to +150 °C)
    * Low-Temperature Option: Silicone (Operating temperature: -40 °C to +80 °C)
• Valve Interface Flange: ISO 5211 / DIN 3337 (F03 through F25) with double-square female drive
• Top & Air Connection Standard: NAMUR VDI/VDE 3845
• Air Supply Ports: G 1/8", G 1/4", G 3/8", G 1/2" threaded connections (or NPT options)
• Visual Position Indicator: High-visibility optical beacon indicator mounted on top pinion
• Mechanical Life Expectancy: Minimum 1,000,000 cycles
• International Standards & Certifications: ATEX (Ex II 2GD c T6), CE, SIL 3 (IEC 61508), ISO 9001