TB when cutting threads with a die. Setting up a machine for thread cutting and methods for quality control of threads. Occupational safety requirements in emergency situations
Page 5-Planar marking.
P.9-Metal cutting
Page 10- Metal filing.
Page 14- Drilling, reaming, countersinking holes
P.18-Thread cutting
Metal cutting
Cutting metal with water, laser cutting metal, plasma cutting of metal, etc. Guide to choosing cutting technology.
The essence of the cutting process is to divide the whole into parts or to obtain parts of a certain shape from the source material (for example, from metal sheet) for the purpose of their further machining and obtaining the final product.
The properties of a metal depend not only on the percentage of various chemical elements, but to a large extent also on the method of its production, as well as thermal and mechanical processing. In addition, the metal may have various defects, which determines its quality.
It should also be borne in mind that in order to optimize your choice, you need to be clear about what your ultimate goal is:
- cutting speed;
- greatest installation versatility;
- minimal level of harmful effects;
- ease of use and good quality cutting performance;
- efficiency;
- possibility of providing consumables and their low cost.
There are two main methods of processing metals: mechanical action and thermal action.
Mechanical impact:
- cutting with scissors, milling, drilling, stamping, sawing, etc.
Thermal influence (the concept of "thermal cutting" can be represented by the general definition of "jet cutting..."):
- laser cutting of metal: stream of luminous particles (photons);
- plasma cutting of metal: plasma jet (flow of ionized particles);
- cutting metal with water: a stream of water under high pressure(with the addition of abrasive - waterjet cutting of metal, without adding abrasive - waterjet cutting of metal);
- oxygen cutting of metal: a stream of oxygen (sometimes mixed with iron powder);
- metal cutting using electrical erosion.
The fundamental difference between these two cutting methods is that when exposed to heat, the use of force is absolutely eliminated, regardless of the thickness of the material being cut.
Table see note.1.
Metal filing
General techniques and rules for filing
The product to be filed is clamped in a vice so that the surface being processed protrudes above the jaws of the vice to a height of 5 to 10 mm. The clamp is made between the mouthpieces. The vice must be set according to the height of the worker, and well secured. When filing, you need to stand in front of the vice, half-turning towards it (to the left or right, depending on need), i.e. turning 45° to the axis of the vice. The left leg is pushed forward in the direction of movement of the file, the right leg is set back from the left by 200-300 mm so that the middle of its foot is opposite the heel of the left leg.
The file is taken in the right hand by the handle, resting its head against the palm; thumb placed on the handle lengthwise with the remaining fingers supporting the handle from below. Having placed the file on the object being processed, apply left hand palm across the file at a distance of 20-30 mm from its end. In this case, the fingers should be half-bent and not tucked in, as otherwise they can easily be injured by the sharp edges of the workpiece. The elbow of the left hand is raised. The right arm - from the elbow to the hand - should form a straight line with the file.
Hand actions when filing.
The file is moved with both hands forward (away from you) and back (toward you) smoothly, moreover, with its entire length. As the file moves forward, it is pressed with your hands, but not equally or evenly. As he moves forward, the pressure increases right hand and ease the pressure. When moving the file back, do not press it. It is recommended to make 40 to 60 double file strokes per minute. When filing planes, the file must be moved not only forward, but at the same time moved to the sides to the right or left in order to file off an even layer of metal from the entire plane. The quality of filing depends on the ability to regulate the pressure on the file. If you press the file with constant force, then at the beginning of the working stroke it will be deflected with the handle down, and at the end of the working stroke - with the front end down. When doing this type of work, the edges of the treated surface will “collapse”.
Methods of filing.
The hardest thing about filing is whether it actually removes this moment that layer of metal and in the exact place where it is needed.
It is possible to correctly file a plane only if a file with a straight or convex, but non-concave surface is selected and if filing is performed by moving the file with an oblique stroke, i.e., alternately from corner to corner. To do this, they first file, say, from left to right at an angle of 30-40° to the sides of the vice. After the entire plane has been traversed in this direction, it is necessary, without interrupting the work (so as not to lose the pace), proceed to filing with a straight stroke and then continue filing again with an oblique stroke, but from right to left. The angle remains the same. As a result, a network of cross strokes is obtained on the plane.
By the location of the strokes you can check the correctness of the processed plane. Let us assume that on a plane sawn from left to right, applying a straight edge reveals a bulge in the middle and a blockage at the edges. It is obvious that the plane was filed incorrectly. If you now continue filing by moving the file from right to left so that the strokes fall only on the convexity, then such filing will be correct. If the strokes are indicated both on the convexity and on the edges of the plane, this will mean that filing is again being carried out incorrectly.
Cooling while drilling
To reduce the friction of the tool against the walls of the hole, drilling is carried out with a supply of cutting fluid (coolant), especially when processing steel and aluminum workpieces. Cast iron, brass and bronze workpieces can be drilled without cooling. Cooling during drilling lowers the temperature of the drill, which heats up from the heat of cutting and friction against the walls of the hole, reduces the friction of the drill against these walls and, finally, promotes chip removal. The use of coolant allows you to increase the cutting speed by 1.4-1.5 times.
An emulsion solution (for structural steels), compounded oils (for alloy steels), an emulsion solution and kerosene (for cast iron and aluminum alloys) are used as coolants. If the machine does not provide cooling, then a mixture of machine oil and kerosene is used as a coolant.
Drilling holes
When drilling holes large diameter The feeding force may be excessively large, which is very tiring for the worker. Sometimes when working with such drills, the power of the machine may be insufficient. In such cases, the formation of holes is carried out sequentially with two drills different diameters, the ratio of which should be such that the diameter of the first drill is greater than the length of the transverse edge of the second drill. Under this condition, the transverse edge of the second drill does not participate in cutting, as a result of which the force required to perform the feed is significantly reduced and, what is very important, the drift of the drill away from the axis of the hole being machined is reduced.
In practice, it is customary to take the diameter of the first drill equal to approximately half of the second, which ensures favorable conditions drill wear and uniform distribution of feed force when both drills are working.
Drilling allows you to obtain more accurate holes and reduce the drift of the drill from the axis of the part. The cutting conditions when drilling holes are the same as when drilling.
Countersinking
A more productive tool for increasing the diameter of holes produced by casting or stamping drilling compared to a twist drill is countersink.
Countersinks are made from high speed steel, less commonly for severe cutting conditions, are equipped with carbide inserts.
Countersinks with a conical shank are used for processing holes with a diameter of 10 to 40 mm. By appearance they are somewhat similar to twist drills, but have three helical grooves and, therefore, three cutting edges, which increases the rigidity of their design, allows increasing cutting modes compared to drilling, and, consequently, productivity.
Mounted countersinks - solid and equipped with carbide plates - are used for processing holes with a diameter of 32 to 80 mm. These countersinks have four helical flutes and therefore four cutting edges. They are mounted in the tailstock quill of the machine using a mandrel on which they are centered conical hole. For processing large holes with a diameter of 50 to 100 mm, attachment countersinks are manufactured with insert knives.
To prevent the countersink from turning during operation, two protrusions (keys) are made on the mandrel, which fit into the corresponding grooves of the countersink.
Benefits of countersinking
The diameter of a hole machined with a countersink, which removes a small allowance and is guided by three (or four) ribbons, is obtained more accurately than when drilling. The absence of the countersink moving away from the axis of the hole being machined ensures the straightness of the hole better than when working with a drill. To reduce countersink drift, especially when processing cast or stitched deep holes, before countersinking, you should bore them with a cutter to the diameter of the countersink to a depth approximately equal to half the length of the countersink.
A countersink is stronger than a drill, so feeds (per revolution of the workpiece) during countersinking can be greater than when drilling. At the same time, a countersink compared to a drill has large quantity cutting edges, so the thickness of the chips removed by each edge is less than the thickness of the chips when drilling. Thanks to this, the surface of the hole processed with a countersink is cleaner. This allows you to use countersinks not only for roughing, but also for semi-finishing of holes after a drill, roughing countersink or roughing cutter - before reaming and even for final processing of holes.
Threading
Thread is a helical groove constant cross section, made on external (external thread) and internal (internal thread) cylindrical or conical surface. It is used to connect parts, as well as to convert rotational motion into translational motion (or vice versa) in mechanisms and machines.
Threads can be single-start, formed by one helical line (thread), or multi-start, formed by two or more lines.
According to the direction of the helical line, the threads are divided into right and left.
Depending on the sizing system, threads are divided into metric, inch and pipe.
IN metric thread, the angle of the triangular profile is 60°, outer, middle and inner diameter s and thread pitch are expressed in millimeters. Metric threads with coarse pitch are designated by a letter and a number expressing outside diameter in millimeters: M6, M12, etc. To designate a thread with a fine pitch (distance between turns), a number is added to this data expressing the thread pitch in millimeters: M6 × 0.6, M20 × 1.5, etc.
IN inch In threads, the angle of the triangular profile is 55°, the thread diameter is expressed in inches, and the pitch is expressed in the number of threads per inch.
Designation example: 1 1/4″ (outer thread diameter in inches).
Pipe thread differs from inch thread in that its initial size is not the outer diameter, but the diameter of the pipe hole, on outer surface which the thread is cut.
Designation example: 3/4″ pipes. (the numbers indicate the internal diameter of the pipe in inches).
Thread cutting is carried out on drilling, turning and special thread-cutting (profile-rolling) machines, as well as manually. At manual processing In metals, internal threads are cut with taps, and external threads are cut with dies.
Depending on the profile of the thread being cut, taps are divided into three types: metric, inch and pipe.
Hand (machinery) taps are usually made in a set of three pieces. The first and second taps pre-cut the thread, and the third taps give it the final size and shape. The number of each tap in the set is marked by the number of marks on the tail. There are sets consisting of two taps: preliminary (rough) and finishing. Taps are made from carbon and alloy steel.
Dies intended for cutting external threads, depending on the design, are divided into round and prismatic (sliding).
Round dies for thread cutting They are secured in a special wrench - a die holder.
Cutting internal thread
To cut an internal thread with a tap (Fig. 1), first prepare a hole. The drill is taken with a slightly larger diameter than the internal diameter of the required thread: if these diameters are equal, then the material squeezed out during cutting will strongly press on the teeth of the tool. As a result, the teeth will heat up and metal particles will stick to them, the thread will end up with torn combs (threads), and the tap may break.
In the table 1 The hole diameters for the most common metric thread sizes are indicated.
External thread cutting
When choosing the rod diameter for external thread(Fig. 2) are guided by the same considerations as when choosing a hole for an internal thread.
In the table 2 The diameters of the rods for the most common sizes of external metric threads are given:
Sources used
http://delta-grup.ru/bibliot/32/46.htm
http://www.stroitelstvo-new.ru/zhestyanye-raboty/ploskostnaja-razmetka.shtml
http://www.electromonter.info/practice/thread.html
http://www.tochmeh.ru/info/sverl3.php
http://www.rostprom.com/spravochniki/napilniki3.html
Page 2- Safety precautions and fire safety when performing plumbing work.
Page 5-Planar marking.
Page 7- Cutting, straightening and bending of metal.
P.9-Metal cutting
Page 10- Metal filing.
· when cutting threads manually in workpieces with strongly protruding sharp parts, you must ensure that when turning the tap with the handle you do not injure your hand;
· to avoid breakage of the tap, you should not work with a dull tap, and when cutting threads in blind holes, you should remove chips from the hole more often;
· special care should be taken when cutting small diameter threads (5mm or less) to avoid breakage of the tap;
· Having put on overalls, carefully tuck your hair under your beret;
· it is necessary to securely secure the workpiece in a vice;
· when filing workpieces with sharp edges, do not tuck the fingers of your left hand under the file during the reverse stroke;
· to avoid injury, the workbench, vice, worker and measuring tool must be kept in order and stored in appropriate places.
CONCLUSION
So, before starting work, you need to clarify the purpose of this very work, then collect everything necessary tools and devices that will be useful to you during your work.
It would be more correct to say that order in the workplace is created not only for aesthetics; first of all, it is created for your safety. Main part domestic injuries associated precisely with the careless use of tools.
And I would like to say that the more carefully you take care of the instrument, the longer it will serve you faithfully.
The student must know: purpose and methods of performing operations when cutting fasteners and pipe thread manually; types of thread; tools and devices; technical equipment; possible types and the reasons for the appearance of marriage; organization and rules for maintaining the workplace; basics of industrial sanitation.
The student must be able to: V correct sequence perform all operations when cutting threads with round fixed and sliding dies; pipe clamp on pipes; determine the dimensions of metric and cylindrical pipe threads from tables; check the quality of the thread; use measuring and testing tools; organize correctly workplace; comply with safety regulations; eliminate defects that occur during thread cutting.
1. What types of threads exist and their purpose?
2. What tool is used to locally increase the size of a hole and process sites?
3. What does cutting speed depend on when machining a hole?
4. In what sequence are internal threads cut by hand?
5. What are the main elements and types of round dies?
6. In what cases are sets of two and three taps used?
7. What causes thread stripping when cutting threads?
8. What defects may occur and how to eliminate them during processing threaded surfaces?
9. Which ones exist? distinctive features inch threads?
10. What types of defects are possible when working with dull tools?
11. What safety regulations must be followed when machining threaded holes?
Topic No. 12 “Riveting. Soldering, tinning, gluing"
Target: introduce students to technical requirements for the upcoming work in the metalwork shop; learn to use tools and devices; sequences of techniques for manual riveting; when soldering hard solders, soft solders with an electric soldering iron; technological process of gluing; with safety rules for riveting, soldering, tinning, gluing; with labor protection and fire safety
Plan
1. Riveting. Tools and accessories for manual riveting.
The question of how to cut a thread with a tap arises in cases where a pre-made hole needs to be prepared to accommodate a bolt, screw, stud or any other type of threaded fastener. In such situations, it is the tap that is the main tool that allows you to quickly and accurately cut an internal thread with the required geometric parameters.
Types and areas of application of taps
Internal thread cutting can be done manually or using machines various types(drilling, turning, etc.). The working tools that perform the main work of cutting internal threads are machine-hand or machine taps.
On different kinds Taps are divided depending on a number of parameters. The following principles for classifying taps are generally accepted.
- According to the method of rotation, a distinction is made between machine-manual and machine taps, with the help of which internal threads are cut. Machine-hand taps equipped with a square shank are used in combination with special device with two handles (this is the so-called knob, tap holder). With the help of such a device, the tap is rotated and cuts the thread. Thread cutting with a machine type tap is carried out on metal cutting machines of various types, in the chuck of which such a tool is fixed.
- Based on the method by which internal threads are cut, a distinction is made between universal (through) taps and complete taps. The working part of the former is divided into several sections, each of which differs from the others in its geometric parameters. The section of the working part that first begins to interact with the surface being processed performs rough processing, the second - intermediate, and the third, located closer to the shank - finishing. Cutting threads with complete taps requires the use of several tools. So, if a set consists of three taps, then the first of them is intended for roughing, the second for intermediate, and the third for finishing. Typically, a set of taps for cutting threads of a certain diameter includes three tools, but in some cases when products made from special hard material, sets consisting of five tools can be used.
- According to the type of hole inner surface which needs to be threaded, there are taps for through and blind holes. A tool for processing through holes is characterized by an elongated conical tip (approach), which smoothly passes into the working part. Universal type taps most often have this design. The process of cutting internal threads in blind holes is carried out using taps, the conical tip of which is cut off and performs the function of a simple milling cutter. This design of the tap allows it to cut threads to the full depth of a blind hole. To cut a thread of this type, as a rule, a set of taps is used, driven manually using a wrench.
- According to the design of the working part, taps can have straight, helical or shortened chip removal grooves. It should be borne in mind that taps with grooves of various types can be used for cutting threads in products made of relatively soft materials– carbon, low-alloy steel alloys, etc. If threads need to be cut in parts made of very hard or viscous materials (stainless, heat-resistant steels, etc.), then taps are used for these purposes, the cutting elements of which are arranged in a checkerboard pattern.
Taps are usually used for cutting metric threads, but there are tools that can be used to cut pipe and inch internal threads. In addition, taps differ in their shape work surface, which can be cylindrical or conical.
Preparing to cut internal threads
In order for the process of cutting internal threads using a tap to not cause any particular difficulties and result in a high-quality result, it is necessary to properly prepare for this technological operation. All methods of cutting threads using a tap assume that a hole with the appropriate diameter has already been made in the workpiece. If the internal thread to be cut has standard size, then to determine the diameter of the preparation hole, a special table with data in accordance with GOST can be used.
Table 1. Diameters of holes drilled for standard metric threads
If the thread that needs to be cut does not belong to the standard category, you can calculate the diameter of the hole to make it using a universal formula. First of all, it is necessary to study the marking of the tap, which must indicate the type of thread being cut, its diameter and pitch, measured in millimeters (for metric). Then to determine the size cross section the hole that needs to be drilled for the thread, it is enough to subtract the pitch from its diameter. For example, if a tool marked M6x0.75 is used to cut a non-standard internal thread, then the diameter of the preparation hole is calculated as follows: 6 – 0.75 = 5.25 mm.
For standard threads belonging to the inch category, there is also a table that allows you to choose the right drill with which to carry out the preparatory work.
Table 2. Diameters of holes drilled for inch threads
An important question to obtain a high-quality result is not only what to use to cut the thread, but also what drill to use to make the preparation hole. When choosing a drill, you need to pay attention to the parameters and quality of its sharpening, as well as to ensure that it rotates in the chuck of the equipment used without runout.
The sharpening angle of the cutting part is selected depending on the hardness of the material that needs to be drilled. The higher the hardness of the material, the greater the sharpening angle of the drill should be, but this value should not exceed 140°.
How to cut threads correctly? First you need to select tools and consumables:
- an electric drill or drilling machine capable of operating at low speeds;
- a drill whose diameter is calculated or selected using reference tables;
- a drill or countersink, with the help of which a chamfer will be removed from the edge of the prepared hole;
- a set of taps of the appropriate size;
- manual holder for taps (drivers);
- bench vice (if the product in which the thread needs to be cut needs to be fixed);
- core;
- hammer;
- machine oil or other composition, which during the processing process must be used to lubricate both the tap and the thread section being cut by it;
- rags.
Features of the technology
When cutting internal threads with a tap, the following algorithm is used.
- In the place on the surface of the workpiece where the hole for threading will be drilled, it is necessary to form a recess for a more accurate entry of the drill, using a core and a regular hammer. The drill is fixed in the chuck of an electric drill or drilling machine, on which low rotation speeds of the tool are set. Before starting drilling, the cutting part of the drill must be treated with a lubricating compound: a lubricated tool enters more easily into the structure of the material being processed and creates less friction in the processing area. You can lubricate the drill with a piece of ordinary lard or grease, and when processing viscous materials, machine oil is used for these purposes.
- If threading is necessary in details small size, they should first be fixed using a bench vice. When starting drilling, the tool fixed in the equipment chuck must be positioned strictly perpendicular to the surface of the workpiece. You should lubricate the tap regularly and ensure that it does not warp and moves strictly in the given direction.
- At the entrance to the hole, as mentioned above, it is necessary to remove the chamfer, the depth of which should be 0.5–1 mm (depending on the diameter of the hole). For this purpose, you can use a larger diameter drill or countersink, installing them in the chuck of drilling equipment.
- The process of cutting internal threads begins with tap No. 1, which is the first to be installed in the driver. We should not forget about the lubricant, which must be applied to the tap for threading. The position of the tap relative to the hole being machined must be set at the very beginning of the work, since later, when the tool is already inside the hole, this will not be possible. When cutting a thread with a tap, you must adhere to the following rule: 2 turns of the tap are made in the direction of cutting the thread, 1 - against the direction. When the tap makes one revolution back, chips are thrown off its cutting part and the load on it is reduced. Thread cutting with a die is performed using a similar technique.
- After cutting the thread with tap No. 1, tool No. 2 is installed in the driver, and after it – No. 3. They are processed according to the method described above. When cutting threads with taps and dies, you need to feel when the tool begins to rotate with force. As soon as such a moment occurs, you should turn the knob reverse side to clear chips from the cutting part of the tool.
This labor safety instruction has been developed specifically for personnel performing work with thread-cutting tools.
1. GENERAL OCCUPATIONAL SAFETY REQUIREMENTS
1.1. Workers over 18 years of age who have undergone a medical examination, introductory briefing on labor protection upon hiring and initial briefing at the workplace, as well as repeated and, if necessary, unscheduled and targeted briefings on labor protection, who have mastered safe techniques, are allowed to work with thread-cutting tools. performance of work and passed the knowledge test of labor protection requirements.
1.2. Employees allowed to perform work must comply with the internal regulations established by the organization.
1.3. When working with thread-cutting tools, you should observe a work and rest regime. Relaxing and smoking are allowed in specially equipped places.
1.4. Threading tools must be assigned to workers for individual or team use and placed in special tool cabinets, tables located next to or inside the equipment, if this seems convenient, safe and provided for by the design.
1.5. Workers are required to perform only the work assigned by the work manager. It is not allowed to delegate your work to other employees and allow unauthorized persons into the workplace.
1.6. An employee may be exposed to hazardous and harmful production factors: noise, vibration, unfavorable parameters of the production microclimate, electricity, gas pollution and dustiness.
1.7. Working clothes, special footwear and other equipment personal protection are issued to employees in accordance with current standards and the work performed.
1.8. Workwear, safety shoes and other personal protective equipment should be stored in specially designated areas in compliance with storage rules and used in good condition.
1.9. Workers performing work with thread-cutting tools must follow the rules fire safety, know fire warning signals, the location of fire extinguishing equipment and be able to use them. It is not allowed to use fire-fighting equipment for business purposes, or to obstruct passages and access to fire-fighting equipment.
1.10. In the event of an accident, the victim should stop working, notify the work manager and apply for medical care.
1.11. Workers performing work with thread-cutting tools need to know and observe the rules of personal hygiene (wash hands with soap and take a shower at the end of work).
1.12. If any questions arise during the work related to its safe performance, you should contact the employee responsible for the safe performance of work.
1.13. Employees who violate the requirements of this instruction are liable in accordance with current legislation Russian Federation.
2. OCCUPATIONAL SAFETY REQUIREMENTS BEFORE STARTING WORK
2.1. Before starting work, you should properly put on and put your work clothes in order: fasten the sleeve cuffs, tuck in the clothes so that there are no flapping ends, tuck your hair under a tight-fitting headdress.
2.2. Inspect the workplace, remove objects that interfere with work and clear passages. Organize your workplace so that everything you need is at hand. The tool at the workplace should be positioned so that there is no possibility of it rolling or falling.
2.3. Make sure there is sufficient lighting in the workplace.
2.4. Check the serviceability of thread-cutting tools (taps, dies, cutters, cutters, rollers and rolling machines):
- they must be sharpened;
— blockages, chipping and burns on cutting edges are not allowed;
— the presence of cracks, chipped places and blockages of cutting edges on the carbide inserts of the tool is not allowed;
— the presence of cracks and traces of corrosion, dents and rough marks on the surface of the taps and dies is not allowed;
— the presence of strips and a decarbonized layer on the working surfaces is not allowed.
2.5. An employee starting work with a thread-cutting tool is not allowed to begin work if:
— the workplace is insufficiently lit;
— the thread-cutting tool is poorly sharpened;
- the task to complete the work has not been received.
3. OCCUPATIONAL SAFETY REQUIREMENTS DURING WORK
3.1. Work only with working tools and devices and use them strictly for their intended purpose.
3.2. While working, do not lean close to the cutting tool.
3.3. Install the item being processed correctly and securely to eliminate the possibility of its fastening being damaged or other problems occurring. technological process during thread cutting.
3.4. The thread-cutting tool must be accurately centered in the machine along the axis of the spindle and tightly seated in the chuck.
3.5. Taps and dies should only be used with proper sharpening.
3.6. Installation and replacement of thread-cutting tools should be done when the machine is completely stopped.
3.7. When installing a thread-cutting tool into fixtures or into a machine, be careful not to cut your hands on the cutting edge tool.
3.8. Do not use a tool with a worn shank.
3.9. It is necessary to ensure that the vice and clamps are in good working order and that the jaws are not cut properly.
3.10. To fasten taps, the use of chucks and devices with protruding unprotected parts (nuts, screws) is not allowed.
3.11. If the fastening of the thread-cutting tool and the part is loosened, the rotation of the tool should be stopped and it should be fastened correctly.
3.12. When turning a product in a chuck or vice together with a tap, it is not allowed to hold it with your hand, but you should stop the rotation of the tool, make the necessary correction or take the appropriate device.
3.13. If the tool jams, the shank, tap or other tool breaks, the machine should be turned off.
3.14. Do not touch the dies with your fingers to identify it. cutting qualities.
3.15. It is not allowed to measure threads with gauges while the product or dies are rotating.
3.16. When installing bolts or rods, their ends must be well threaded to avoid possible thread failures and breakage of dies or guides.
3.17. When cutting threads in deep holes, you should periodically remove the tap from the hole to remove chips.
3.18. Remove chips from the cut thread and table only when the tool is stopped and moved away from the part.
3.19. When working with thread cutting tools, you should:
- first turn on the rotation of the spindle, and then the feed, while the workpiece should be brought into rotation until it comes into contact with the cutter, cutting in smoothly, without impacts;
- before stopping the machine, first turn off the feed, move the cutting tool away from the part, and then turn off the spindle rotation.
3.20. It is necessary to ensure proper installation of the cutter for cutting threads and not to place different pieces of metal under it; use supports equal to the area of the cutter.
3.21. The cutter should be clamped with the minimum possible overhang and at least three bolts. It is necessary to have a set of shims of various thicknesses, length and width not less than the supporting part of the cutter. The use of random pads is not permitted.
3.22. When manually cutting threads, do not press hard on the cutting tool or hold the part with your hands.
4. OCCUPATIONAL SAFETY REQUIREMENTS IN EMERGENCIES
4.1. You should stop working, turn off the equipment you are using, and report the incident to the work manager if at least one of the following situations occurs:
— malfunction of equipment;
— faulty operation of vices and clamps;
— damage to the working tool;
— appearance of smoke or smell characteristic of burning insulation;
— the appearance of increased noise, knocking, vibration;
— faulty power wiring;
— break of the protective grounding conductor;
- lack of lighting.
4.2. In case of an accident you should:
- take measures to free the victim from the traumatic factor;
— provide the victim with first aid depending on the type of injury;
- inform management about the incident;
— if possible, maintain the situation if this does not lead to an accident or injury to other people;
— if necessary, call an ambulance by calling 103 or help transport the victim to a medical facility.
4.3. In the event of a fire, you should:
- stop working;
— turn off electrical equipment;
— call the fire department by calling 101 and inform the organization’s management;
— begin to extinguish the fire using available fire extinguishing means.
5. OCCUPATIONAL SAFETY REQUIREMENTS AFTER WORK COMPLETION
5.1. Tidy up the workplace, put tools and devices in a specially designated place, remove shavings from the work table, clean tools and devices from dust and dirt, carefully fold finished parts and workpieces.
5.2. Remove protective clothing and personal protective equipment and store them in the prescribed manner.
5.3. Wash your face and hands with warm water and soap or take a shower.
5.4. Inform the work manager about the work performed and any problems.
Filing(filing) is the removal of a layer from the surface of the workpiece using a cutting tool - a file.
At sawing works The following safety requirements must be met:
when filing workpieces with sharp edges, do not tuck the fingers of your left hand under the file during the reverse stroke;
the shavings formed during the filing process must be swept off the workbench with a hair brush; It is strictly forbidden to throw away chips with bare hands, blow them off or remove them with compressed air;
When working, you should use only files with firmly attached handles;
It is prohibited to use files without handles or files with cracked or split handles.
Safety precautions when drilling and reaming holes
Drilling called the process of creating holes in solid material cutting tool - drill.When working on drilling machine The following safety requirements must be observed:
correctly install and securely secure the workpiece on the machine table and do not hold it with your hands during processing;
do not leave the key in the drilling machine after changing the cutting tool;
start the machine only with firm confidence in the safety of operation;
do not handle the rotating cutting tool and spindle;
do not remove broken cutting tools from the hole by hand, use special devices for this;
To remove a drill chuck, drill or adapter sleeve from the spindle, use a special wrench or wedge;
do not transmit or receive any objects through a working machine;
do not operate the machine wearing gloves;
Do not lean on the machine while it is operating.
The holes produced by drilling do not have a high frequency of processed surface or accuracy, so they are subjected to additional processing by deployment. Reaming can be done both on drilling and lathe machines, and manually special tools, called sweeps. At reaming holes It is necessary to comply with the same safety requirements as for drilling.
Safety precautions when cutting threads
carved called a helical surface formed on bodies of rotation. Threading– the operation of obtaining a screw thread on a workpiece is performed manually or on various machines.
At tapping threads the machine must comply with safety requirements, drilling machines.
When cutting threads with taps and dies manually in parts with strongly protruding sharp parts, be careful not to injure your hands when turning the funnel.
During the cutting process, it is necessary to carefully ensure that there is no distortion of the tap.
To get a clean thread with the right profile and not to spoil the tap, you need to use cutting fluids when cutting threads
Do not use machine or mineral oils when cutting threads.
When cutting a thread with a die, to prevent defects and breakage of the die teeth, it is necessary to ensure that the die is perpendicular to the rod: the die must cut into the rod without distortion.
Safety precautions when riveting
Riveting is the process of joining two or more parts using rivets.
To protect against noise when riveting pneumatic hammers use anti-noise headphones.
When adjusting a pneumatic tool, you should not try the hammer while holding the crimp with your hands, since due to the high impact force it is very difficult to hold it, as a result your hands may be damaged. The support should not be squeezed in your hands, it should only be directed towards the rivet.
It is not allowed to work with a poorly seated hammer, the handles of the hammers should not have cracks, there should be no cracks, chips, or gouges on the crimps and tensions, and the support should not be squeezed tightly in the hands.
