Hydraulic Hammer

Hydraulic Hammer

 

a machine for working metal by blows from falling parts driven by fluid under high pressure. Hydraulic hammers are used for forging, closed-impression die forging, and sheet-metal stamping. They are similar in design to hammers utilizing other types of power—for example, steam hammers. Hydraulic hammers are not widely used because of the difficulty of controlling the impact force.

Table 1. Properties of some hydraulic fluids
 Viscosity at 50°C
(m2 per sec
)
Freezing point (°C)Flash point (°C)
*At 100°C
Hydraulic oil for automatic lines of metal-cutting lathes...............(25-35) × 10−6-10190
Oil for presses...............1 × 10−7*-15200
Oil for hydraulic drives of GT-50 diesel locomotives...............(11-14) × 10−6-28165
Oil for motor vehicle hydraulic systems
hydromechanical transmissions...............
(3.5-4) × 10−6*-45160
torque converters and automatic gearboxes...............(23-30) × 10−6-40175
power steering...............(12-14) × 10−6-45163
Oil for high-load mechanisms
(ESh)...............
20 × 10−6-50150
Shock-absorber fluid (AZh-12T)...............12 × 10−6-55165
Hydraulic brake fluid (GTN oil)...............1 × 10−7-6392
Alcohol-glycerine fluids
SG...............
6.2 × 10−6-5028
SVG...............2.5 × 10−6-6028
SVG-2...............7.5 × 10−6-5030
Alcohol-castor oil fluids
ESK...............
(8.2-8.6) × 10−6-2512
BSK...............(9.6-13.8) × 10−4-2514
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Engine: 4-stroke, 4-cylinder, diesel, direct injection; loading equipment: bucket capacity not more than 1 m3; excavator equipment: bucket capacity not more than 0.18 m3; equipment: double transport lock, locking the excavator equipment from lowering and turning; flashing light; contour for hydraulic hammer; front wheel wings with shock absorbing brackets to prevent breaking; telescopic handle; jaw multifunctional bucket Document Purchase Start date : 12 Jul 2019
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Finally, from inside the garage, a hydraulic hammer could be heard battering the wall.
The soft-gas cycle is intended to reduce the risk of hydraulic hammer that can occur on the coil or connected piping by reducing the pressure difference between the coil and the hot-gas main.
"Parts most prone to damage are wear items, such as tools and tool bushings on any hydraulic hammer. These service items need inspection, and replacement varies widely based on maintenance schedule and a good operator, a key person who can extend wear life of components," he says.
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