Instruction Manual for the DQL100-G2 Suspended Compass Angle Measuring Instrument

DQL100-G2 Instruction Manual for the Model Suspended Compass Angle Measuring Instrument

Product Implementation Standard: Q/HGY06-2020

• Uses of the instrument  

DQL100-G2 Type suspension compass angle measurer and FD-200 The two types of slope gauges are provided as a set for measuring horizontal and inclination angles in mine shafts and tunnels.

The instrument is primarily used for measuring magnetic azimuths in secondary roadways of the mining area and at the working face, as well as the dip angles of compass traverse lines.

The structure of this instrument has the following characteristics:

1 The overall structure is designed based on the angle-measurement method known as the “cross-rope method”; therefore, in mine shafts and tunnels subject to external magnetic interference—such as those with metal support structures or containing iron, nickel, and other such minerals—it is relatively convenient to measure horizontal angles.

2 It retains the basic structure of a conventional suspended compass and, in the absence of external magnetic interference, can be used as a standard suspended compass to measure magnetic azimuth.

• Basic Parameters

1 , Magnetic needle length:                100mm

2 , Minimum graduation of the dial:           1 degree

3 , Estimated reading:                30 ′

4 , Instrument net weight: 0.5 kg

5 , External dimensions:               320 times 170 times 20 （ mm )

III. Instructions for Use

The end of the magnetic needle wrapped with copper wire is the south pole.

1 , in the absence of magnetic interference :

As with a conventional compass, simply attach the hook on the semicircular suspension beam and the cantilever hook to the surveying rope, and you can proceed with measuring the magnetic azimuth.

2 , Effects of Magnetic Materials :

Due to the presence of magnetic materials, the underground mine workings no longer experience a uniform geomagnetic field; instead, it is a ( or several ) A composite magnetic field is formed by the magnetic body and the Earth’s geomagnetic field. Since the magnetic field of the magnetic body is non-uniform, the composite magnetic field is also non-uniform. Consequently, even when the instrument is used at different positions along the same survey line, the varying magnetic field strengths at these locations result in different magnitudes of magnetic force acting on the magnetic needle, leading to different deflection angles. Therefore, in the presence of a magnetic body, the instrument cannot be operated according to the standard procedures used in the absence of magnetic interference.

In this situation, two common methods of use are typically employed.

Method 1:

According to the diagram 1 The hook on the instrument’s semicircular suspension beam 1 Using a measuring rope 2 Hanging at the measurement point 3 Above, position the instrument directly beneath the measurement point, with the cantilever hook extended. 5 Measurement ropes hung on the front and rear sights, respectively. 6 and 8 Up ( Can be assisted by a spring clip. 4 Limited Cantilever Hook 5 the position to ensure the instrument is used correctly ) The difference between the two readings of the index scale is the horizontal angle being measured.

When measuring using this method, since the instrument is close to the top beam, ( or roof panel ) If the position makes reading difficult, the reflector can be inserted into the socket at the lower end of the suspension beam hook, and its position adjusted so that the reading can be taken through the reflector. In addition, the three measuring ropes 2、6、8 Must be from the measurement point. 3 A small deviation will arise from this. Otherwise, a minute error will exist.

If the shed beam comes into contact with the measuring rope, use an appropriately weighted object to press the rope down, as shown in the figure. 1 Medium and heavy objects 7。

Method 2:

According to the diagram 2 Hang the instrument using the lifting beam hook. 1 Use a measuring rope. 2 Hanging over the measurement point 3 Above, the instrument is距底板 6 Height 1 Approximately one meter, adjusted to ensure convenient observation by the observer. Extend the rear-view measuring rope. 4 One end is tied to the backsight rod, while the other end is held by hand, and the taut measuring rope 4 Vertical measuring rope for the suspended instrument 2 , so that the two measuring ropes just touch; at this point, the measuring rope pulled taut by hand indicates the backsight direction, and the cantilever hook 5 Hang the surveying tape on this measuring rope; once the magnetic needle comes to rest, its index reading will indicate the composite magnetic azimuth of the backsight. Using the same method, the composite magnetic azimuth of the foresight can be determined; the difference between the two is the horizontal angle being measured.

The choice between Method 1 and Method 2 depends on individual preference and the specific site conditions: when the roof slab or canopy beam is relatively high, Method 2 is clearly more suitable; conversely, when the roof slab or canopy beam is low and there are no obstructions to the placement of the fore-and-back sight leveling rods, Method 1 is preferable to Method 2.

The inclination angle of mine shafts and tunnels can be measured using a slope gauge. On a taut measuring rope, at equal distances from each end, One third Measure at the station, taking the arithmetic mean of the two observations as the final value. When the tilt angle is small, the instrument can be suspended slightly above the midpoint of the measuring rope. ( of rope length 3/5 place ) A single measurement at the location.

Several Notes (in the presence of magnetic interference, i.e., when using Method 1 and Method 2 for measurement) :

1 The instrument readings on the fore-sight and back-sight cantilevers do not represent the true magnetic azimuth; rather, they reflect the magnetic azimuth of the resultant magnetic field.

2 During both the foresight and backsight measurements, the instrument must remain stationary in space. When the instrument is set up at the same location for both foresight and backsight observations, any errors caused by external magnetic fields will be equal in magnitude but opposite in sign. These errors will cancel each other out when calculating the horizontal angle, ensuring that the measured angle value is unaffected by such errors.

When there is no influence from non-magnetic materials, the true magnetic azimuth in the forward direction is a , subsequently denoted as β, then the horizontal angle is ψ. ₁ =a- β. Assuming that, in the presence of magnetic interference, the error caused by the magnetic material is δ, the forward-looking measurement then becomes a+ δ, the rear view changes to β + delta ( Synthetic Magnetic Azimuth ) then the horizontal angle ψ ₂ =(a+ delta )-( beta + delta )=a- β, the result is mountain ψ ₁= psi ₂ This indicates that, when used in this manner, the instrument can eliminate the influence of ferromagnetic materials.

If the instrument’s position changes between the two measurements, then δ ₁ ≠δ ₂ , so ψ ₁ ≠ψ ₂ Therefore, during the two measurements—one with the front view and one with the rear view—the instrument’s spatial position must remain unchanged.

3. During use, adjust the instrument’s vertical position to minimize the angle θ between the plane of the cantilever ring and the instrument’s plane, as shown in the figure. 3 The purpose is to increase the effective distance between the two hooks, improve the guiding performance of the cantilever, and enhance measurement accuracy.

IV. Completeness of the Instrument Set

1、DQL100-G2 Suspended Compass Protractor         1 Taiwan

2、FD-200 Type slope gauge                     1 one

3 , spring clip                             1 to

4 , rearview mirror                              1 one

5 , instrument leather case                            1 one

6 , User Manual                          1 portion

7 , Certificate of Conformity                              1 Zhang

V. Instrument Maintenance

1 The instrument should not be placed in damp or high-temperature environments.

2 When the instrument is not in use, the braking screw must be tightened to lift the magnetic needle, thereby preventing friction between the pivot tip and the glass bearing.

3 After use, the instrument should be placed in its leather case, and it is recommended to align the magnetic pole of the compass needle with the geomagnetic pole so that its magnetism can be preserved for a long time.

4 During use or transport, prevent the instrument from being subjected to impacts or any vibrations that could damage it.

Harbin Optical Instruments Factory Co., Ltd.

HARBIN OPTICAL INSTRUMENT FACTORY LTD.

ground   Address: Jingwei Third Road, Daoli District, Harbin City 32 Number

Post   Editor: 150010

Electricity   Words: 400-030-0319         0451-84286338      

network   Address: www.hrboptical.com           

E-mail： hopt@hopt.cn