Device Overview

1.1 Name and Model

Name: Fully Automatic Flexural and Compressive Strength Testing Integrated Machine
Model: DYE-300-10S

1.2 Execution Standard: GB/T 17671–2021, JC/T960–2022 “Methods for Testing Cement Paste Strength (ISO Method)”

1.3 General Function Overview: This testing machine is primarily used for flexural and compressive strength tests of cement mortar, and is widely employed in the construction industry. With its compact design and simple operation, it is an indispensable piece of equipment for cement plants, construction engineering units, quality inspection stations, and colleges and universities. The machine utilizes hydraulic loading and electronic force measurement, equipped with a dedicated hydraulic valve assembly to achieve automatic loading at a constant rate. The testing process and data processing are fully automated via computer control, featuring a color screen with Chinese character menu prompts, real‑time display of force values and loading curves, standard keyboard input, automatic storage and processing of test data, automatic printing of test reports, long‑term data storage with on‑demand retrieval, as well as overload protection and other advanced functions.

Technical Parameters

Installation of the Testing Machine

The foundation for installing this testing machine must be firm and reliable. To facilitate operation and ensure accurate readings, the base may be slightly elevated above ground level, with the height determined according to actual needs. A minimum clearance of 0.7 meters should be maintained around the testing machine to allow for easy maintenance and operation. The anchor bolts (M12 × 300 mm) should be installed using a two‑stage grouting process to ensure proper bolt embedding.
(See the installation base in the diagram.)

Basic Diagram of the Testing Machine

During installation, the testing machine must be kept level (levelness ≤ 0.2/1000). Use a 0.1/1000 box-type spirit level to measure the plane of the lower pressure plate. If either the transverse or longitudinal level deviates from the specified tolerance, shims can be added beneath the base plate for correction, then tighten the anchor bolts. Next, connect the power cord; the machine’s electrical system must be equipped with proper grounding and safety protection devices, and the supply voltage should not vary by more than ±10% of the rated value.

Repair and Maintenance

4.1 The testing machine shall be installed in a clean, dry environment with uniform temperature, free from vibrations and corrosive gas exposure.

4.2 The testing machine shall be kept clean, and parts of the testing machine that lack a protective coating should be regularly oiled to prevent rust.

4.3 After the testing machine has been in use for six months to one year, the oil should be changed once. When changing the oil, thoroughly clean the oil tank and the oil filter. To clean the oil tank, pour kerosene into the tank, let it circulate through the system, then drain it out—repeat this process several times until the tank is completely clean. Next, wipe the bottom of the tank dry with a towel, and then fill it with clean hydraulic oil. If you notice that the hydraulic oil has become severely cloudy and is no longer suitable for use, it should be replaced immediately; otherwise, it will accelerate wear on various hydraulic components, potentially affecting the accuracy of the measured values.

4.4 Hydraulic Oil Specifications: The following recommendations are provided based on different ambient temperatures:
(1) When the ambient temperature is between 10–20°C, use GB-443-84 N46# (equivalent to 30# mechanical oil).
(2) When the ambient temperature is between 20–30°C, use GB-443-84 N86# (equivalent to 40# mechanical oil).

4.5 When not in use, the machine should be covered with a plastic cover.

The machine’s main structure and operating principle

This testing machine is primarily composed of a main frame, a hydraulic system, a computer, and a control system.

5.1 Main Unit of the Flexural–Compressive Testing Machine

The main body of this testing machine consists of a 30T compression section, a 1T flexural section, and the housing. The 30T compression section includes: the upper beam, wheel‑spoke sensors, vertical columns, upper pressure plate, 30T compression fixture, lower pressure plate, tray, hydraulic cylinder, and piston; the 1T flexural section includes: sensors, 1T flexural fixture, lower pressure plate, shims, tray, hydraulic cylinder, and piston. The operating principle is that the oil pump supplies oil to the working hydraulic cylinder, and the movement of the piston drives the lower pressure plate to move up and down, thereby conducting compression and flexural tests.

5.1.1 Cylinder and Piston

The oil cylinder and piston are the core components of the main unit. The oil cylinder is placed directly on the pallet, while the piston is installed inside the oil cylinder. The seal for the pressurized oil is maintained by the clearance between the oil cylinder, the sealing ring, and the piston; the return stroke is accomplished by the piston’s own weight, which brings it back to its original position. The lower end of the 30T oil cylinder is equipped with two threaded holes, which connect to the inlet oil pipe from the hydraulic valve group and the return plastic pipe for the overflow oil from the oil cylinder piston, respectively. Similarly, the lower end of the 1T oil cylinder has two threaded holes that connect to the inlet oil pipe from the hydraulic valve group and the return plastic pipe for the overflow oil from the oil cylinder piston, respectively.

5.2 Oil Supply System

5.2.1 Measurement and Control System
The system employs EHC series measurement and control units and EasyTest measurement and control software to form a microcomputer‑controlled electro‑hydraulic pressure testing machine control system. The measurement unit is equipped with high‑precision hydraulic sensors, enabling real‑time acquisition of load data from the pressure testing machine and automatic processing of test data. The system features high control accuracy, strong adaptability, and excellent long‑term stability. The spoke sensors are installed on the 30T crossbeam, while the 1T composite sensors are mounted on the 1T crossbeam.

5.2.2 Hydraulic System

The hydraulic system consists of a hydraulic pump, drive motor, digital valve, pressure reducing valve, solenoid directional control valve, oil tank, oil filter, connectors, and oil lines.
The hydraulic pump is an axial piston ultra-high-pressure pump driven directly by an electric motor and mounted on the oil tank. It automatically adjusts the oil inflow to the cylinder via a hydraulic valve manifold, thereby achieving the desired loading rate. Once the test is complete, the system automatically unloads, allowing all oil from the cylinder and from the oil pump to flow back into the oil tank. During testing, the oil in the oil tank passes through an oil filter screen into the oil pump and then into the cylinder via the hydraulic valve manifold. Under the action of pressurized oil, the piston moves upward, driving the lower platen and, in turn, causing the grips to apply various loading tests to the specimen.

5.2.3 Pressure Reducing Valves, Digital Valves, and Solenoid Directional Control Valves

A pressure reducing valve can adjust the oil inflow rate and the kinetic energy of the incoming oil, resulting in different pressure losses and thereby achieving the purpose of pressure reduction.
The digital valve uses a motor as its power source and drives the movement of the valve spool via gear and screw pairs, thereby controlling the opening size of the valve port and regulating the loading rate.
The solenoid directional control valve opens or closes different drain ports by controlling the movement of the valve body, while the inlet port remains normally open. Hydraulic oil then flows into the various drain lines and, through oil pressure, pushes the piston inside the cylinder.

Installation and Debugging

6.1 Installation

This testing machine should be installed in a clean, dry room with uniform temperature. The fluctuation range of the power supply voltage should not exceed ±10% of the rated voltage. The machine’s electrical system must be equipped with proper grounding and safety protection devices. Since hydraulic oil is used, appropriate fire‑safety measures must be in place around the machine. The foundation may be raised slightly above ground level by 30–50 mm. The testing machine should be positioned at least 0.8 m away from the wall, with ample space left around it to ensure sufficient operational clearance and access for inspection purposes. To level the main unit, place a spirit level on the surface of the test table and adjust the horizontal alignment in both longitudinal and transverse directions (use a spirit level with an accuracy of 0.2/1000 mm to achieve a deviation of no more than ±2 divisions). Once the machine is securely stabilized, carefully mount the measurement and control system onto the corresponding mounting location on the top of the right-hand cabinet, then connect the pressure sensors and electrical connectors properly.

6.2 Selection of Hydraulic Oil Specifications

In hydraulic systems, high‑quality mineral oil with medium viscosity should be used. The oil must be free of water, acids, and other impurities, and it should remain stable—neither decomposing nor thickening—at room temperature. Before being filled into the machine, the oil must be thoroughly filtered. Improper oil selection can lead to valve and oil line blockages, and may even compromise the accuracy of the testing machine’s readings, thereby affecting its normal operation. Recommended oil specifications: This equipment typically uses L-HM46 anti‑wear hydraulic oil; in regions with higher ambient temperatures, hydraulic oil with a higher viscosity should be employed. Depending on the specific conditions, L-HM68 anti‑wear hydraulic oil may be added to increase viscosity.

6.3 Refueling and Fuel Drain

Before opening the front door of the control cabinet, you’ll see a small round cover. Push the cover open to reveal a small hole—this is where oil is injected into the tank during refueling. Each fill typically adds about 46 liters of oil, and you should refer to the oil level indicator on the front of the tank to ensure the oil level isn’t too low.
The shelf life of oil depends on local climate conditions; if you notice that the oil has begun to become cloudy or contaminated and is no longer suitable for use, it should be replaced with fresh oil.

6.4 Initial Operation and Trial Run

6.4.1 Before the first startup after installation, you should first check whether the oil level in the oil tank is sufficient. You can refer to the oil dipstick; if the oil level is insufficient, open the small round cap and add oil to the tank until the oil level reaches the mark on the dipstick.
6.4.2 Check all oil pipe joints and fasteners for looseness; tighten any that are loose. Ensure the dust covers are intact and undamaged. Verify that the power wiring and voltage are correct.
6.4.3 Turn on the power to the computer system and controller, then enter the test mode. For detailed test procedures, please refer to the attached “User Manual for the Pressure Testing Machine Control Software.” (Please note: Before entering the pressure testing machine’s operating system, be sure to close all other real-time control software and applications running on the computer. Users are also advised not to install non‑genuine software on the computer to avoid virus infections; any resulting consequences will be borne by the user.)
6.4.4 Start the oil pump motor to bleed the air from the main cylinder of the testing machine, so as to avoid affecting the stability of the load. To bleed the air: start the oil pump, click “Run” on the test interface to raise the piston a certain distance, then click “Stop” to allow the hydraulic oil to flow back from the main cylinder into the oil tank. Repeat this process several times to completely remove all air.
6.4.5 Wipe the surface of the test specimen clean and inspect it for any obvious defects. If any defects could affect the test results, the non‑destructive test specimen must be replaced.
6.4.6 Place the fixture’s positioning frame, aligned with the presser bar’s positioning line, directly in the center of the lower presser bar. Then, insert the test specimens into their respective fixtures and adjust the fixtures to the appropriate position according to the size of the test specimens.
6.4.7 Perform zeroing according to the operating procedures and promptly enter and modify all relevant data.
6.4.8 Click “Run” to perform the loading test at the desired rate, steadily increasing the load until the specimen is crushed and the load begins to decrease.
6.4.9 After the test is completed, click the “Report” button to print the test report for that session.
Note: Bleeding air from the oil pump and oil cylinder is only performed during the first test run; thereafter, this procedure should only be carried out when changing the oil or if deemed necessary.

6.5 Precautions During Operation

6.5.1 Before use, carefully read this instruction manual and the accompanying “User Manual for the Pressure Testing Machine Measurement and Control System Software.” During testing, if the oil pump suddenly stops working due to certain special reasons, immediately cut off the power supply and release the applied load. After inspection, restart the power supply to resume testing; do not attempt to start the pump under load, as this may damage the oil pump.
6.5.2 During testing, if control suddenly fails, the power supply should be cut off immediately to stop the machine from running.
6.5.3 During operation, the lifting height of the lower platen must not exceed 4 cm to prevent accidents.
6.5.4 During operation, it is prohibited to place any part of the human body, including hands, between the fixtures; operators are not allowed to stand directly in front of the testing apparatus during the test, and they must pay attention to the risk of injury from flying fragments when the specimen breaks.
6.5.5 After the test, promptly remove the fractured specimens for the next test. When no further tests are to be conducted, disconnect the power supply.
6.5.6 Operators who are not authorized to operate this machine are prohibited from doing so.

Packing List