First, product introduction;
The mortar point load meter is developed according to GB / T50315-2000 << Technical Regulations for On-site Inspection of Masonry Engineering >>. It is an instrument for testing the strength of masonry mortar. It can be directly tested on site or in the laboratory without affecting the wall Stress performance, with the characteristics of easy detection, convenient operation, short time required, and high test accuracy, can fully meet the objective needs of on-site quality control of masonry projects and quality appraisal and evaluation of old and ancient buildings.
Second, structure and principle;
The point load meter consists of a worm wheel, a worm mechanical loading system, a pressure sensor and a microcomputer peak display.The sensor is installed on the base of the loading system.The peak display and the loading system are connected by wires.
During work, place the pre-prepared mortar sample on the indenter, and slowly turn the handle of the point load meter clockwise with your hand to move the lifting screw downward.When the loading head is against the mortar sample **, Pressure load, and then slowly and uniformly apply the load until the test piece is broken. At this time, the microcomputer peak display keeps the large A load.
★ A大行程: 30mm
★ 电源电压: 4.5V
★净 重: 4.8kg
Third, the technical parameters:
A long range: 3KN
★ A large stroke: 30mm
★ Power supply voltage: 4.5V
Net weight: 4.8kg
★ Dimensions: 350X150X20mm
★ 仪器使用前,先将传感器与微电脑峰值显示器的连线接好,然后接通电源将显示器上电源开关打开,此时“加荷”指示灯亮,观察显示器上的数字是否为零若不为零应按“置零”键, 使其清零.
Fourth, use method:
★ Before using the instrument, first connect the sensor to the microcomputer peak display, then connect the power to turn on the power switch on the display. At this time, the "load" indicator is on, and observe if the number on the display is zero. You should press the "Zero" key to clear it.
★ Press the "Peak" key, the peak indicator light is on, and the load can be applied at this time. When the test piece is broken, the display shows the value of A, the unit is N.
When the next test piece is pressed, press the "Peak" key to light up the loading indicator. The previous test data is eliminated. If the value displayed on the display is zero (smaller values drift on the display is normal), then press the "Peak" key. Make the "peak" indicator light, and then load for the next test. If the display shows a large value, press the "zero" key to clear it when the "load" light is on. Repeat the above procedure for each test. However, when the peak indicator is off, the display has no peak protection function, and the displayed value will automatically disappear with unloading.
Large pieces of mortar peeled at each measuring point are processed (or selected) into test pieces that meet the following requirements: thickness 5-20mm, estimated action radius 15-25mm, and the large surface should be flat, but its edges are not required to be very regular .
Draw the point of action on the mortar sample, and measure its thickness t with a caliper, accurate to 0.1 mm.
Place the mortar sample on the lower loading head, align the upper and lower loading heads with the pre-drawn action points, and slowly turn the handle of the point loader clockwise with your hands to move the lifting screw down through the worm wheel and worm drive. When the loading head is pressed against the mortar sample, a compressive load is generated, and then the load is slowly and uniformly applied until the test piece is broken, and the loading is stopped at this time.
After recording the peak display readings, insert the formula to calculate the intensity.The reading unit of the point charge meter display is N.
★ Splice the damaged specimens as they are, and measure the short distance A from the actual point of load to the edge of the specimen as the radius of action, accurate to 0.1 mm.
Note: Do not directly press the upper and lower loading heads. If the upper and lower loading heads are required to perform this inspection, a mortar sheet must be placed between the upper and lower loading heads to avoid damage to the loading heads.
★ Verification of instrument
The instrument has been calibrated with the standard instrument before leaving the factory. The sensor needs to be re-calibrated after a period of use. The user can remove the four fixing screws on the back cover of the display and remove the front panel. (The potentiometer below is used to adjust the zero point).
The indicator is under the "loading" light, and the loading and unloading test is repeated. After the verification, the adjustment screw is sealed tightly to prevent changes from vibration.
Five, maintenance and upkeep:
After the instrument is used, it should be cleaned up and packed in a box for future use
The microcomputer peak display is assembled with integrated circuits, and the power supply voltage should be stable in the range of 220V ± 5V when in use.
The instrument should be used and stored in a dry place indoors. Avoid exposure to sunlight, rain and moisture to extend the service life.
★ Yellow dry oil should be regularly injected into the worm gear box to keep it lubricated.