Manual Hydraulic Pump

I. Basic Definition and Working Principle

1. Definition

    

   Driven by a handle, the piston/plunger reciprocates to periodically change the pump chamber volume, drawing in and discharging hydraulic oil, converting human power into high-pressure energy for the hydraulic system.

    

   Built-in check valves control flow direction, and safety valves prevent overpressure.
    
2. Working Cycle
    

• Oil Suction: When the handle is lifted, the pump chamber expands to create a vacuum, and oil enters through the suction check valve.
• Oil Discharge: When the handle is pressed down, the pump chamber contracts and oil pressure rises, flowing into the execution system through the discharge check valve.
• Two-stage pump (common in high-pressure models): Low-pressure large flow for rapid advance, high-pressure small flow for pressure holding / precision control, balancing efficiency and pressure.

II. Core Structure Components

• Pump body (cylinder barrel), piston/plunger, operating handle;
• Check valve group (anti-backflow);
• Safety valve / relief valve (overpressure protection, typically set at 63MPa, etc.);
• Oil tank / reservoir, oil outlet / return port, pressure gauge port;
• Seals (prevent oil leakage, determine service life and pressure stability).

III. Main Classification and Features

1. By Pressure Level

• Low-pressure pump (<7MPa): Large flow, used for low-pressure lifting and conveying;
• Medium-pressure pump (7–31.5MPa): General industrial assembly;
• High-pressure / ultra-high-pressure pump (31.5–100+MPa): Bolt tensioning, hydraulic testing, mine rescue.

2. By Oil Circuit Type

• Single-acting: Oil discharges only during the down stroke; return relies on dead weight / spring. Simple structure, low cost;
• Double-acting: Oil discharges in both up and down strokes, higher efficiency and faster speed.

3. By Stage

• Single-stage pump: Simple structure, low cost;
• Two-stage pump: Low-pressure fast advance + high-pressure slow push, labor-saving and efficient.

IV. Core Advantages

1. No electricity / air supply required: Suitable for outdoor, high-altitude, underground, power-off repair and other extreme scenarios;
2. Portable and compact: Small size, light weight (around 10kg commonly), with handle / shoulder strap for easy movement;
3. Safe and controllable: Pressure and flow can be finely adjusted; built-in safety valve prevents overload;
4. Low maintenance cost: No complex electrical parts; only regular oil change and seal inspection needed;
5. Wide pressure range: From several MPa to over 100MPa, adapting to various working conditions.

V. Typical Application Scenarios

• Industrial assembly: Hydraulic bolt tensioners, flange separation, bearing press-fitting;
• Engineering machinery: Field hydraulic tools (hydraulic cutters, cut-off tools, punching machines), jacks;
• Testing industry: Hydrostatic / burst testing of pressure vessels, pipelines, valves;
• Rescue: Fire rescue and demolition, hydraulic tools for road accident rescue;
• Electric power / railway: Crimping of high-voltage line fittings, installation and adjustment of track equipment.

VI. Selection and Daily Maintenance Points

1. Selection

    

   Prioritize matching the maximum pressure and flow required by the system;

    

   Consider working conditions (portability, low temperature / explosion protection);

    

   Interface specifications and compatibility with hydraulic oil.
    
2. Maintenance
    

• Use recommended-grade hydraulic oil, replace regularly and keep clean;
• Avoid oil contamination to prevent valve blockage;
• Store in a dry place to prevent rust;
• Strictly prohibit overpressure use; calibrate safety valves regularly.
• I. Basic Performance Parameters (Core Selection Basis)​
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  Parameter Category​	Specification Range​	Selection Instructions​	Application Matching Examples​
  Rated Working Pressure​	100-300MPa (Standard), 3000-40000psi (Graded)​	Should be 10%-20% higher than the maximum system working pressure; select 20000-40000psi models for ultra-high pressure scenarios (e.g., aerospace testing)​	Industrial Fastening → 100-150MPa; Aerospace Testing → 30000-40000psi​
  Maximum Overload Pressure​	1.5 times the rated pressure​	Automatically controlled by a safety valve to avoid system damage from overpressure; verify safety valve trigger accuracy during selection​	200MPa Rated Model → 300MPa Maximum Overload​
  Displacement (Single Stroke)​	Single-stage: 1.6-70cm³/stroke; Two-stage: Low-pressure 33cm³/stroke + High-pressure 1.6cm³/stroke​	Choose two-stage pumps for high-frequency operations (low-pressure large flow improves efficiency); single-stage pumps for low-frequency operations​	Rapid Jacking → Two-stage 33+1.6cm³/stroke; Precision Testing → Single-stage 12-25cm³/stroke​
  Theoretical Flow Rate​	0-40L/min (DN6), 40-80L/min (DN10), etc.​	Match by pipe diameter: DN6 for flow ≤40L/min, DN10 for 40-80L/min (Mnemonic: Flow determines pipe diameter)​	Small Cylinder Drive → DN6 (≤40L/min)​
  Operating Force​	≤350N (Standard), ≤50N (Effort-saving Type)​	Ergonomic design; recommend effort-saving models with 1:12 lever ratio for high-pressure models to reduce operational fatigue​	Long-term Operations → ≤50N Effort-saving Type​

   

   

   

   

   

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  II. Structural & Material Parameters (Critical for Environment Adaptation)​
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  Parameter Category​	Optional Specifications​	Selection Instructions​	Applicable Scenarios​
  Pump Body Material​	Aluminum Alloy, Steel, 316 Stainless Steel, 17-4PH Precipitation Hardening Steel​	Aluminum alloy (lightweight) for standard environments; 316 stainless steel (temperature resistance: -200℃ to 800℃) for corrosive/high-temperature environments​	Chemical Industry → 316 Stainless Steel; Heavy Machinery → Steel​
  Seal Material​	NBR (Nitrile Rubber), FKM (Fluoroelastomer), Nylon​	FKM for high-temperature/corrosive media; NBR for standard hydraulic oil; nylon-reinforced seals for ultra-high pressure scenarios​	Petroleum Industry → FKM; General Industry → NBR​
  Drive Type​	Single-acting, Double-acting​	Single-acting for single-piston rod cylinders; double-acting supports bidirectional drive (requires directional valve)​	Unidirectional Jacking → Single-acting; Reciprocating Operations → Double-acting​
  Oil Tank Configuration​	Tankless, 1-10L Aluminum/Plastic Tank​	Tank-equipped models (with oil level sight glass) for mobile operations; tankless models (external oil circuit) for fixed scenarios​	Rescue Operations → 3-5L Tank; Equipment Integration → Tankless​
  Interface Type​	FNPT Thread (Low-pressure), Autoclave Ferrule (High-pressure)​	FNPT thread (self-sealing) for 3000-10000psi; double ferrule interfaces (zero leakage) for 20000-40000psi​	Ultra-high Pressure Testing → Autoclave Ferrule Interface​

   

   

   

   

   

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  III. Adaptation & Installation Parameters (Core for System Compatibility)​
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  Parameter Category​	Specification Range​	Selection Instructions​	Notes​
  Oil Outlet Specification​	Quick Couplers (Male/Female), Standard Threaded Interfaces​	Must match the actuator interface; prioritize quick couplers with dust caps for easy disassembly and maintenance​	Confirm cylinder interface type (Male/Female)​
  Pipe Diameter Specification​	6, 10, 16, 20, 25, 32mm​	Reverse verification by flow: DN16 for 80-160L/min, DN20 for 160-250L/min​	Avoid excessive pressure drop and heat generation from undersized pipe diameter​
  Pressure Gauge Accuracy​	±1% (Mechanical Gauge), Digital Sensor​	Digital sensors (support data output) for precision testing; mechanical gauges for standard operations​	Laboratory Testing → Digital Sensor; On-site Maintenance → Mechanical Gauge​
  Installation Method​	Portable (Handheld), Fixed Installation​	Portable for models ≤11kg; fixed installation (with mounting bracket) required for heavy-duty models​	Outdoor Emergency → Portable; Workshop Station → Fixed Installation​

   

   

   

   

   

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  IV. Safety & Environmental Parameters (Compliance Requirements)​
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  Parameter Category​	Standard Configuration/Specifications​	Selection Instructions​	Relevant Standards​
  Safety Protection​	Built-in Safety Valve, Pressure Relief Valve​	Automatic pressure relief at 10% overpressure (response time .1s); overpressure protection is mandatory​	Complies with ISO 4413 Hydraulic System Safety Standard​
  Operating Temperature Range​	-30℃ to 55℃ (Standard), -200℃ to 800℃ (Special)​	Select models compatible with low-temperature hydraulic oil for cold environments; verify material thermal stability for high-temperature scenarios​	Outdoor Winter → -30℃ Adaptable Type; High-temperature Workshop → Special Model for >55℃​
  Explosion-proof Grade​	Explosion-proof Design (Optional)​	Explosion-proof certified models required for high-risk environments (e.g., coal mines, oil & gas) to avoid spark hazards​	Underground Operations → Explosion-proof Type; General Environment → Standard Type​
  Maintenance Cycle​	Seal Inspection Every 6 Months​	Shorten to 3 months for high-frequency use; replace hydraulic oil regularly (per oil level sight glass prompt)​	Daily Operations → Maintenance Every 3 Months​

   

   

   

   

   

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