Created on:2021-06-15 15:20

Technical requirements of low speed and high torque hydraulic motor

Technical requirements of low speed and high torque hydraulic motor

(6) Technical requirements

① General technical requirements. The nominal pressure series shall comply with GB 2346. The nominal displacement series shall comply with the provisions of GB 2347. The dimensions of mounting flange and shaft extension shall comply with GB / T 2353.2.

The type and size of threaded oil port shall comply with GB 2878. Other technical requirements shall comply with 1.2-1.4 of GB 7935-87.

Note: the dimensions of installation flange and shaft extension and oil port of imported and old products shall be in accordance with relevant regulations.

② Performance

a. Displacement. The no-load displacement should be in the range of 95% - 110% of the geometric displacement.

b. Volume efficiency and total efficiency. Under rated conditions, volumetric efficiency and total efficiency shall meet the requirements of the table below.

c. Start up efficiency. The minimum starting efficiency under rated pressure shall comply with the provisions in the table below.

d. Low speed performance. Under the conditions of maximum displacement, rated pressure and specified back pressure, the minimum speed of hydraulic motor shall meet the requirements in the table below.

e. Noise. The noise value shall meet the requirements in the table below.

f. Low temperature performance. There shall be no abnormal phenomenon during the low temperature test.

g. High temperature performance. There shall be no abnormal phenomenon during the high temperature test.

h. Overspeed performance. There shall be no abnormal phenomenon during the overspeed test.

i. External leakage. The static seal shall not leak oil; the dynamic seal shall not drip oil within 3 hours.

j. Durability. The durability test is carried out according to the following scheme: full load test 1000h, reversing test 50000 times, overload test 10h.

Note: if there are special requirements, it can be carried out according to the special technical specifications.

After the durability test, the decrease value of volumetric efficiency shall not be more than three percentage points; the parts shall not have abnormal wear and other forms of damage.

 

Efficiency, minimum speed and noise

project

Nominal displacement V / L · R-1

zero point zero two

>0.02~0.056

>0.063~0.14

>0.16~0.28

>0.315~0.56

>0.63~1.00

>1.25~2.80

>3.15~7.10

>8.00~12.50

>16.00~25.00

>25.00

Inner curve radial piston motor

Volumetric efficiency /%

 

≥93

≥92

≥91

≥90

Total efficiency /%

 

≥85

≥84

≥83

Minimum speed /%

 

≤5

≤4

≤3

≤2

Start up efficiency /%

 

≥80

Noise / DB (a)

 

≤84

≤82

≤80

Crankshaft connecting rod radial piston motor

Volumetric efficiency /%

 

≥92

≥91

 

Total efficiency /%

 

≥83

≥84

 

Minimum speed /%

 

≤20

≤18

≤15

≤12

≤9

≤7

 

Start up efficiency /%

 

≥75

 

Noise / DB (a)

 

≤82

≤80

 

Crankshaft radial piston motor without connecting rod

Volumetric efficiency /%

≥92

≥91

 

Total efficiency /%

≥74

≥78

≥82

 

Minimum speed /%

≤40

≤30

≤25

≤18

 

Start up efficiency /%

≥75

 

Noise / DB (a)

≤85

≤83

 

Radial ball motor

Volumetric efficiency /%

Single speed, double speed

 

≥92

 

 

≥91

 

Total efficiency /%

Single speed, double speed

 

≥85

 

 

≥83

 

Minimum speed / R · min-1

 

≤6

≤5

≤4

 

Start up efficiency /%

 

≥78

 

Noise / DB (a)

 

≤81

 

Double swash plate axial piston motor

Volumetric efficiency /%

 

≥92

≥91

≥90

 

Total efficiency /%

 

≥83

≥83

≥84

 

Minimum speed /%

 

≤15

≤10

 

Start up efficiency /%

 

≥75

 

噪声/dB(A)

 

≤82

≤81

≤80

 

 

③ Processing quality. According to JB / T 5058, the machining quality is classified. The AQL value of qualified quality level is specified in (10).

④ Assembly quality. The technical requirements of component assembly shall comply with 1.5-1.8 of GB 7935-87.

a. Air tightness. There shall be no air leakage during the air tightness test.

b. Internal cleanliness. The internal cleanliness evaluation method and cleanliness index shall comply with the provisions of JB / T 7858 (see the table below).

 

Cleanliness index of low speed high torque hydraulic motor

低速大扭矩

液压马达规格

公称排量V/L·r-1

≤1.6

>1.6~8

>8~16

>16~25

清洁度指标/mg

120

240

390

525

 

⑤ Appearance requirements. Appearance requirements shall comply with 1.9 and 1.10 of GB 7935-87.

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