1Function and scope of application of the testing machine

MPV-20Celectro-hydraulic servoPVThe friction testing machine adopts the form of sliding friction and can conduct tests under various conditions, including drip lubrication and no lubrication, as well as changing parameters such as load, speed, time, friction partner material, surface roughness, hardness, etc.Mainly used to evaluate the friction and wear performance of bearing materials such as plastics, powder metallurgy, alloys, etc., and to determine the reasonable fit clearance of bearingsPVValue. It can also be used to measure bearing temperature rise, friction coefficient, and wear.

This testing machine can meet the standardsGB/T 7948-1987Limit period of plastic bearingsPVRequirements for Test Methods

2. Brief description of the structural characteristics and functions of the testing machine

2.1Main structure

The testing machine consists of two parts: the host and the control system.

The host part includes the machine base, spindle and drive system, hydraulic loading system, sample clamping part, friction torque measurement and electromechanical interlocking protection system. The control system includes measurement and control, display instruments, hydraulic oil sources, and computer data processing parts. The two parts are connected by control cables and hydraulic hoses.

2.2working principle

The spindle of the testing machine is driven by a motor and connected to the spindle through a coupling and torque sensor. The experimental force is completed through a hydraulic loading system.

Main spindle control mode of the testing machine: time control, speed control.

Automatic parking due to time alarm.

2.3Institutional characteristics

Spindle and drive system: The spindle box is installed on the machine base, and the spindle is supported by a set of bearings with high rotational accuracy. Add to the spindle boxN32Hydraulic lubrication is used to lubricate the spindle bearings, ensuring their normal operation at high speeds. The rear of the spindle is connected to the torque sensor and motor through a coupling. There is a safety pin next to the coupling, which is used to lock the spindle and cut off the power supply of the main motor when replacing the sample during shutdown, achieving electromechanical interlocking safety protection.

Hydraulic loading system: A hydraulic loading system is installed at the lower front of the machine base, which can apply a larger load to the specimen on the spindle20kNRadial load.The hydraulic loading system consists of a cylinder piston, an electro-hydraulic servo valve, an oil pressure sensor, and an oil source. Its working principle is shown in the diagram6As shown. In the picture:1Mesh filter,2Three phase AC motor,3Plunger pump,4Pressure pipeline filter,5Pilot operated relief valve,6Solenoid valve,7Pressure gauge switch,8Pressure gauge,9Electro hydraulic servo valve,10Solenoid valve. Three phase AC motor driveThe dynamic piston pump extracts hydraulic oil through a mesh filter, filters it through a pressure pipeline filter, and supplies oil to the electro-hydraulic servo valve. The working pressure of the electro-hydraulic servo valve is set by a pilot operated relief valve and is greater than the hydraulic pressure corresponding to a larger test force, indicated by a pressure gauge. When a forward current is applied to the electro-hydraulic servo valve, its inlet port passes through its load port1Connected to the oil cylinder, pressure oil enters the cylinder, and the test force increases. The magnitude of the test force is measured by a load sensor installed on the upper end of the piston. When the magnitude of the test force is equal to the set value, the control system places the valve core of the electro-hydraulic servo valve in the neutral position to close its opening. With the leakage of oil in the cylinder, the control system can open the electro-hydraulic servo valve at any time to replenish the oil, thereby maintaining the stability of the test force. When reverse current is applied to the electro-hydraulic servo valve, its return port passes through its load port1Connected to the oil cylinder to achieve unloading. solenoid valve6Used for system uninstallation, solenoid valve10Used for rapid oil return in hydraulic cylinders.

Sample clamping part: for internal samplesM20×2The nut is tightened at the front end of the spindle1﹕7On the conical surface, use a retaining nut to lift off the inner sample during disassembly. The outer sample is tightly fixed inside the outer sample ring, and the screw on the outer sample ringNails are used to prevent the outer specimen from rotating with the inner specimen during operation. When measuring the temperature of the sample under dripping oil lubrication, it is necessary to use a special accessory to drill holes on the sample. Adjusting the needle valve on the oil cup can change the amount of oil dripping.

Friction force measurement and alarm system: During the test process, the inner and outer specimens rotate relative to each other, generating friction torque. After processing by the torque measurement system, it displays that when the friction torque exceeds the set value, an alarm is triggered and the machine is stopped for protection.

3.Main technical parameters and performance indicators

3.1Greater testing power:20kN

3.2Test force accuracy: ±1%

3.3Spindle speed range:200r/min～2800 r/min

3.4Spindle speed control accuracy: ±10 r/min

3.5Greater friction torque:40N·m

3.6Friction torque measurement accuracy: ±3%

3.7Temperature measurement range: room temperature~200℃

3.8Temperature measurement accuracy: ±2℃

3.9Input voltage: AC380V 10%

3.10Input power:11Kw

4.working conditions

The testing machine operates normally under the following conditions:

4.1at room temperature10℃～35Within the range of ℃;

4.2Relative humidity not exceeding80%In the environment;

4.3In an environment without vibration, corrosive media, and strong electromagnetic interference;

4.4The fluctuation range of the power supply voltage should not exceed ± of the rated voltage10%The frequency fluctuation should not exceed the rated frequency2%；

4.5Correctly installed on a stable foundation, with a levelness of0.2/1000.

5.Main configuration and some device parameters of the testing machine

6Acceptance, installation, debugging, and training

1. acceptance

(a)The equipment undergoes pre acceptance before shipment, and then undergoes acceptance. Pre acceptance is conducted by the supplier, and acceptance is conducted by the purchaser.

(b)Acceptance criteria: The agreement serves as the basis for acceptance.

2Installation and debugging

（a） After the equipment arrives, the ordering party completes the positioning under the guidance of the supplier. The installation, wiring, and debugging are the responsibility of the supplier. After receiving the notification, the supplier should arrive at the installation location of the ordering party as soon as possible.

（b） All technical performance indicators must meet the requirements specified in the contract and technical documents, and the installation, commissioning, and acceptance of equipment must be carried outshouldComply with relevant national regulations and standards.

3Personnel training

After pre acceptance, the supplier is responsible for providing technical training to the purchaser, so that the trainees can master the testing operation, adjustment, and basic troubleshooting.

7Quality Assurance

The equipment warranty period is within one year from the date of formal delivery and lifetime service. During the warranty period, the supplier shall provide timely and free maintenance services for any equipment malfunctions, and replace any parts damaged by non-human factors in a timely and free manner. If the equipment malfunctions during use outside the warranty period, the supplier shall promptly provide service to the ordering party and actively assist in completing the repair task.

8Confidentiality of Technical Intelligence and Information：

（a）This technical solution belongs to our company's technical information, and the user shall assume confidentiality obligations for the technical intelligence and information provided by us. Regardless of whether this solution is adopted or not, this clause shall remain valid for a long time;

（b）We also assume confidentiality obligations for the technical intelligence and information provided by users.

Shandong Keser Testing Instrument Co., Ltd