Some standard content:
Mechanical Industry Standard of the People's Republic of China
JB/T2548.2—96
Bed Milling Machine
Published on April 11, 1996
Technical Conditions
Implemented on October 1, 1996
Ministry of Machinery Industry of the People's Republic of China
Mechanical Industry Standard of the People's Republic of China
Bed Milling Machine
1 Subject Content and Scope of Application
Technical Conditions
This standard specifies the requirements for the manufacture and acceptance of bed milling machines. This standard applies to vertical and horizontal bed milling machines with a worktable width of 320~1250mm. Cited standards
GB3932
GB5226
GB9061
JB3579
JB4139
ZBJ50003
ZBJ50004
ZBnJ50008.1
ZBnJ50008.3www.bzxz.net
ZBJ50016
3 General requirements
Precision of milling machines without lifting the worktable
General technical conditions for electrical equipment of machine tools
General technical conditions for metal cutting machine tools
General technical conditions for epoxy coated sliding guides, metal Technical conditions for safety protection of cutting machine tools and machine tool accessories Determination of cleanliness of metal cutting machine tools
Metal cutting machine tools
Metal cutting machine tools
Metal cutting machine tools
Determination of sound pressure level of noise
General technical conditions for machined parts
General technical conditions for assembly
General technical conditions for hydraulic systems
JB/T2548.2-96
Replaces JB331483
This standard is a concretization and supplement to GB9061, ZBnJ50008.1, ZBnJ50008.3 and other standards. When accepting machine tools according to this standard, the remaining acceptance items in the above standards that are not concretized by this standard must be inspected at the same time. 4 Accessories and tools
4.1 The following accessories and tools shall be supplied randomly: a. Milling cutter bar, 1 set; b. Pull rod, 1 set; c. Machine iron pad, 1 set; d. Anchor bolt, 1 set; e. Special adjustment tool, 1 set.
4.2 The following special accessories may be supplied upon agreement: a. Vertical milling head; b. Universal milling head; c. Speed increasing chuck; d. Dividing head; e. Flat-nose pliers; f. Rotary table.
Approved by the Ministry of Machinery Industry on April 11, 1996
Implemented on October 19, 2001
5 Safety and Health
JB/T2548.2-96
The guide surfaces of the bed, column, saddle, workbench, spindle box, ram and other parts should be equipped with protective devices. 5.2 The movement of the column, saddle, workbench, spindle box, ram and other parts should be equipped with safety devices to limit or prevent collision. 5.3 When the power or control signal is interrupted, the feed transmission should stop no later than the main transmission, and the braking and clamping actions should not be interrupted. 5.4 When the machine tool is fed or moved quickly, the operating handwheel (handle) should be automatically disengaged and should not rotate. 5.5 The noise of the machine tool should be tested according to the provisions of ZBJ50004, and the measurement should be carried out under the condition of idling. The sound pressure level of the whole machine noise shall not exceed 83dB (A). 5.6 The operating force of the handwheel (handle) shall not exceed the provisions of Table 1. Table 1
Handwheel (handle) Name
Spindle box lifting handwheel
Workbench longitudinal movement handwheel
Workbench lateral movement handwheel
Slider movement handwheel
Spindle sleeve movement handwheel
Machine tool weight
5.7 When accepting machine tools according to this standard, the remaining acceptance items in JB4139 that are not specified in this standard and the acceptance items specified in standards such as GB5226 and ZBJ50016 must be inspected at the same time. 6 Processing and assembly quality
6.1 The bed, column, saddle, workbench, spindle box, ram, column slide, and spindle box slide are important castings. After rough processing, they should be aged or other measures should be taken to eliminate internal stress. 6.2 For the vulnerable parts of the main parts of the machine tool, such as the spindle, spindle sleeve, screw pair and high-speed and heavy-load gears, wear-resistant measures should be taken that are compatible with the service life.
6.3 The workbench and saddle guide pair, saddle and bed guide pair, column and bed guide pair, ram and vertical slide guide pair, vertical slide and column guide pair, workbench and bed guide pair, spindle box and column guide pair are important guide pairs, and wear-resistant measures such as wear-resistant cast iron, steel inlay, plastic coating or high (medium) frequency induction quenching should be adopted. 6.4 The following joint surfaces shall be assessed according to the requirements of "important fixed joint surfaces": a. Fixed joint surface of the screw bracket:
b. Fixed joint surface of the nut seat:
c. Fixed joint surface of the suspension beam;
d. Fixed joint surface of the sliding guide plate. 6.5 The following joint surfaces shall be assessed according to the requirements of "particularly important fixed joint surfaces": a. Fixed joint surface of the front and rear bed bodies;
b. Fixed joint surface of the column and bed body;
c. Fixed joint surface of the column and column slide: d. Fixed joint surface of the spindle box and the spindle box slide. 6.6 The following guide pairs shall be assessed according to the requirements of "sliding (rolling) guides": a. Bed guide pair:
b. Column guide pair;
c. Worktable guide pair:
d. Ram guide Rail pair.
JB/T2548.2—96
6.7 The plastic-coated and coated guide rails should fit tightly to the substrate, with firm and reliable bonding, without gaps and bubbles, and the contact with the matching guide rails should be uniform, and should comply with the relevant provisions of JB3579. 6.8 The inlaid steel guide rails should be subjected to flaw detection after refractory testing, and no cracks should be found. 6.9 The reverse idle stroke of the handwheel (handle) with a scale device that is directly driven by the screw shall not exceed 1/20r, and the reverse idle stroke of the other handwheels (handles) shall be assessed in accordance with the design regulations.
6.10 The cleanliness shall be inspected in accordance with the provisions of ZBJ50003, and the cleanliness of the inside of the spindle box and the hydraulic box shall be inspected by weight (spot check). The weight of impurities and dirt shall not exceed 400mg/L for the spindle box and 10 for the hydraulic box. 0mg/L. 6.11 The following important locating pins shall be inspected by color coating method, and their contact length shall not be less than 60% of the working length. a. Locating pins of columns and bed:
b. Locating pins of front and rear bed.
7 Machine tool idle operation test
7.1 The main motion mechanism of the machine tool shall be tested for idle operation in sequence from the lowest to the highest speed (the stepless speed change shall have at least 10 speeds). The operation time of each level shall not be less than 2min, and the operation time at the highest speed shall not be less than 1h. The spindle bearings shall reach a stable temperature. The temperature and temperature rise shall be measured near the spindle bearings. The temperature shall not exceed 70℃, and the temperature rise shall not exceed 40℃. 7.2 The actual deviation of the spindle speed of the step-driven transmission shall not exceed -2%~+6% of the value indicated on the nameplate: the actual deviation of the feed speed shall not exceed The actual deviation of the spindle speed and feed speed of the stepless transmission within the range of -5% to +3% of the indicated value on the label shall not exceed ±10% of the indicated value on the label. 7.3 The main motion mechanism is tested for 10 times of forward and reverse jogging, continuous starting and stopping at medium speed. The action should be flexible and reliable. 7.4 The main motion mechanism is tested for speed change operation at low, medium, high (stepless speed change) or all levels (stepped speed change) spindle speed. The action should be flexible and reliable.
7.5 The moving parts on the linear motion axis are tested for 10 times of positive and negative continuous starting and stopping at medium feed speed. The action should be flexible and reliable.
7.6 The feed motion mechanism is tested for speed change operation at 10 feed speeds including low, medium and high. The action should be flexible and reliable. 7.7 The hydraulic system, cooling system and lubrication device of the machine tool are tested. The operation should be reliable, and the operation and adjustment should be convenient and flexible. 7.8 For machine tools with automatic broaching devices, the tool locking and loosening tests must be carried out continuously for no less than 5 times, and the movements should be flexible and reliable. 7.9 Test the safety, insurance and protection devices of the machine tool, and the functions should be reliable, and the movements should be flexible and accurate. 7.10 The ratio of the idling power of the main transmission system to the rated power of the main motor should not exceed the provisions of Table 2. Table 2
Working table width
Idling powerRated power of main motor%35
8 Machine tool load test
8.1 The machine tool should be subjected to the following load tests:
JB/T2548.2—96
a. Operation test with the maximum weight of the workpiece (spot check); b. Test of the maximum torque of the main transmission system; c. Test of the main transmission system exceeding the maximum torque by 25% for a short time; d.Test of maximum cutting resistance;
e. Test of exceeding the maximum cutting resistance by 25% in a short time; f. Test of the main transmission system reaching the maximum power (spot check). 8.2 Operation test of bearing the maximum weight of the workpiece 8.2.1 Use a weight equivalent to the maximum weight of the workpiece specified in the design as the workpiece, and place it on the worktable to make the load uniform. 8.2.2 Use the lowest and highest feed speeds and fast to run the worktable, and the machine tool should be stable and reliable. When running at a low feed speed, the worktable should not have obvious creeping phenomenon.
8.3 Test of the maximum torque of the main transmission system and exceeding the maximum torque by 25% in a short time 8.3.1 Within the constant torque range of the main transmission system, select an appropriate spindle speed and use milling to conduct the test. Adjust the cutting amount so that the main transmission system reaches the maximum torque specified in the design. 8.3.2 The test method for the main transmission system exceeding the maximum torque by 25% in a short time is the same as 8.3.1. Adjust the cutting amount so that the main transmission system reaches 125% of the maximum torque specified in the design. 8.3.3 The material of the test piece is HT200 or 45 steel, and the cutting tool is an insert end mill. 8.3.4 During the test, all parts of the machine tool should work normally and reliably. 8.4 Test of maximum cutting resistance and short-term test exceeding 25% of the maximum cutting resistance 8.4.1 Select an appropriate spindle speed within the constant torque range of the main transmission system, use milling to conduct the test, and adjust the cutting amount so that the machine tool reaches the maximum cutting resistance specified in the design. 8.4.2 The test method for short-term test exceeding 25% of the maximum cutting resistance is the same as Article 8.4.1. Adjust the cutting amount so that the main transmission system reaches 125% of the maximum cutting resistance specified in the design. 8.4.3 The material of the test piece is HT200 or 45 steel, and the cutting tool is an insert end mill. 8.4.4 During the test, all parts of the machine tool should work normally, all motion mechanisms should be flexible and reliable, and the overload protection device should be normal and reliable. 8.5 Test of the main drive system reaching maximum power 8.5.1 Select an appropriate spindle speed within the constant power speed range of the main drive system and use milling to conduct the test. Adjust the cutting amount so that the power of the main drive system reaches the rated power of the motor. 8.5.2 The test piece material is HT200 or 45 steel, and the cutting tool is an insert end mill. 8.5.3 During the test, all parts of the machine tool should work normally without obvious frontal vibration, and the metal removal rate should be recorded. 9
Machine tool precision inspection
9.1 Precision inspection shall be carried out in accordance with GB3932, and the cutting specifications for working precision shall be in accordance with the design documents. 9.2 The following items in GB3932 should be inspected when the machine tool spindle runs at medium speed and reaches a stable temperature: a. G6 Radial runout of the axis of the spindle taper hole; b. G7 Parallelism of the spindle rotation axis to the worktable surface; c. G8 Verticality of the spindle rotation axis to the worktable surface; d. G9 Parallelism of the spindle rotation axis to the lateral movement of the worktable (column or ram). 9.3 When testing the working accuracy, the R value of the surface roughness of the test piece should not be greater than 3.2μm. 4
Additional instructions:
JB/T2548.2-96
This standard was proposed by the National Technical Committee for Standardization of Metal Cutting Machine Tools. This standard is under the jurisdiction of the Beijing Milling Machine Research Institute. This standard was drafted by the Shanghai Fourth Machine Tool Factory. This standard was first issued in 1983.
Mechanical Industry Standard
Technical Conditions for Bed Milling Machines
JB/T2548.2-96
Published and issued by the China Academy of Mechanical Science
Printed by the China Academy of Mechanical Science
(No. 2 Shouti South Road, Beijing: Postal Code 100044)*
Format 880×1230
Print Sheet 1/2
Word Count 10000
First Edition in October 1996
First Printing in October 1996
Print Quantity 1-500
Price 500 Yuan
96-015
Mechanical Industry Standard Service Network: http/AvwwJB.ac.cn96
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