Device Overview

1.1 Name and Model

Name: Micro-Electro-Mechanical Hydraulic Servo Universal Material Testing Machine

Model: WAW-300B

1.2 Overview of Functions This series of testing machines is primarily used for tensile, compressive, and bending tests on metallic materials, and is equipped with a cold‑bending attachment to also perform cold‑bending tests on metal materials. Consequently, these testing machines meet the experimental needs of research institutions, construction contractors, metallurgical plants, mechanical manufacturing facilities, and laboratory departments at various types of schools.

The working cylinder of this series of testing machines adopts a bottom-mounted design, uses hydraulic pressure for loading, employs sensors to measure force, and features digital display of force values. It is equipped with a loading speed indicator window that allows the user to adjust the loading speed at any time. The machine is easy to operate, boasts stable performance, and offers safe and reliable operation. This series of testing machines consists of two independent components: the main unit and the load cell.

Technical Parameters

3. Machine Systems and Operating Principles

This unit is divided into two parts: the main unit and the force gauge, which are connected via oil lines.

3.1 Host Machine

The main unit consists of a highly adjustable support frame (comprising a base screw and a moving crossbeam) and a working frame (composed of a work cylinder, piston, and worktable,

Because we focus, we excel.

It consists of two main components: the crossbeam and the upper crossbeam. The working principle involves a high‑pressure oil pump supplying oil to the working cylinder; as the piston moves, it drives the worktable and the upper crossbeam upward, enabling tensile or compressive testing of specimens. Tensile tests are conducted between the upper crossbeam and the moving crossbeam of the main frame, while compressive tests are performed between the worktable of the main frame and the moving crossbeam. Adjustment of the test space is primarily achieved by using the drive mechanism to raise and lower the moving crossbeam.

3.1.1 Working Cylinder and Piston

The working cylinder and piston are the main components of the machine. The cylinder is fixed to the machine base, and a spherical joint is installed between the piston and the worktable. During the return stroke, the piston is pressed back by its own weight. The pressure oil is sealed by the thin oil film between the cylinder and the piston, while the inner surface of the cylinder provides guiding. Thanks to the self‑aligning function of the spherical joint, friction between the cylinder and the piston caused by lateral forces is significantly reduced.

3.1.2 Moving Crossbeam and Drive Mechanism

The moving crossbeam is supported on the lead screw via a transmission nut. The lead screw can rotate in both forward and reverse directions, and its rotation is driven by a drive mechanism mounted at the bottom. The moving mechanism consists of a reduction motor, sprockets, and a chain; the reduction motor drives two lead screws to rotate in synchronization through the sprockets and chain.

3.1.3 Piston Stroke Limit Device

(1) Workbench (2) Limiting Pull Plate (3) Limit Switch (4) Bumper Rod (5) Oil cylinder, piston (6) Base

A limit switch 3 is installed between workbench 1 and base 6. As the piston rises, it drives the limit pull plate 2 to rise together; when the contact rod 4 comes into contact with the spring-loaded rod of the limit switch, the oil pump power is immediately cut off, thereby realizing a safety protection function.

3.1.4 Speed Reduction Mechanism

1. Lead screw 2. Large Sprocket 3. Adjust the idler wheel 4. Drive Sprocket 5. Pistons, Cylinder Housings 6. Chain

(1) A reduction mechanism is mounted on the base; among them, 4 is the driving sprocket that drives the chain in motion, 1 is a symmetrical lead screw, 2 is the large sprocket mounted on the lead screw, 3 is the tension-adjusting idler gear, 5 is the piston cylinder, and 6 is the chain.

(2) The chain has been properly adjusted before leaving the factory, so users do not need to make any further adjustments.

(3) Pay special attention when operating the moving crossbeam: be sure not to use the moving crossbeam to apply force—its sole function is to rise and fall under no-load conditions.

3.2 Force Gauge

This testing machine employs a fully automatic servo control system, which is composed of a fully automatic hydraulic clamping system and an industrial PC. The force measurement component consists of the control system, a pressure…

It consists of a force sensor, an industrial PC, and a printer. For detailed operating instructions, please refer to the User Manual for the Fully Automatic Measurement and Control System.

3.3 Hydraulic Pressure Control System

The hydraulic control system comprises a high‑pressure oil pump for the load cell, digital valves, solenoid valves for the hydraulic grips, a digital data acquisition system, an industrial PC, and the working piston of the main unit’s oil cylinder. During testing, the hydraulic fluid flows from the oil pump’s outlet pipe into the digital valve; the digital valve then uses the control signals from the data acquisition system to deliver oil to the main unit’s cylinder. As the working piston moves upward, it drives the main unit’s worktable, the crossbeam on the optical column, and other components to apply load to the specimen. Simultaneously, pressurized oil is routed through the digital valve to transmit equal pressure to the press sensor. After being calculated and processed by the data acquisition system, the resulting data is displayed in digital form on the industrial PC.