Introduction
Tungsten carbide measuring tool has high hardness, high strength, excellent wear and corrosion resistance so that it can effectively ensure the accuracy and stability of testing. Compared with other materials, it has longer service life.According to the different applications, it can be divided into LG (gauge), LH (ring gauge), LS (male gauge), LK (caliper) and LC (micrometer gauge) five series of tungsten carbide.

LG (gauge): It includes LG30 and LG35, the specifications consist of rough gauge code, code size and variable size;
LH (ring gauge): The specifications consist of rough ring gauge code, inner and outer diameter and height;
LS (male gauge): The specifications consist of rough male gauge code, inner and outer diameter and height;
LK (caliper): The specifications consist of rough caliper code, width, length and thickness;
LC (micrometer gauge): The specifications consist of rough micrometer gauge code, outer diameter and thickness.

Operation and Maintenance
1. Before measuring: Check whether zero, with or without corrosion, abrasion or scratch the case with a soft cloth or wipes wiping workpiece surface burrs, oil and slug;
2. Measuring: Contacted with the workpiece appropriately and avoid touching the measuring surface to protect the tool;
3. After measuring: It should be clean in time, coated with anti-rust oil and check regularly.

Tungsten carbide step drill is also called as tow drill, which is mainly used in less than 3mm steel sheet drilling and can replace many drills. It can process pores with different diameters and large pore in one step, and do not replace the drill bit or drill positioning hole. There are some types of tungsten carbide step drill:
According to the shapes of groove: It can be divided into straight groove, circular groove and spiral groove;
According to the edges: Single-blade, double-blade, three-blade, four-blade and multi-blade step drill;
The step drill has a standard, but most of are the non-standard customized.

In the process of tungsten carbide step drill manufacturign, it should be noticed that:
1. Process reference: Straight shank step drills structure is relatively simple, and in the assembled state to work longer large diameter main positioning surface. So a large diameter axis as a reference not only to meet the functional requirements, but also in processing and analog reference checks easier;
2. Dimensional accuracy: The accuracy of large and small diameter (D, d) has a remarkable effect on the aperture. The process may be subjected to coarse grinding, grinding to control the drill diameter;
3. Position accuracy: In order to avoid over-tolerance, it should be positioned by the reference axis in sharpening process;
4. Surface quality: Surface quality mainly refers to the condition of the surface layer of the drill, including surface roughness and surface hardness, if not meet the requirements, it will affect the tool wear resistance, fatigue strength and corrosion resistance.

Tungsten carbide floating reamer has both of axial floating and vertical swing movements, so it can effectively compensate for the deviation caused by thermal deformation, reamer installation. It has been widely used in automobile engines, ship engines and hydraulic, medical, energy and other require high-precision reaming fields. There are some notice when you are using tungsten carbide floating reamer:
1. In the milling process, reamer can not be reversed in the hole, so as not to damage or blunt cutting edge;
2. It should stop turning after reamer out of the hole in case of the pull marks in wall;
3. The accuracy of reaming hole has been affected by many factors, such as reamer size, surface toughness, clamping ways, the materials and cutting fluid performance. So it should have a test before the batch processing to avoid the wastage;
4. After using, it should clean up the chips in groove and coated with oil and put in sheath to prevent the cutting edge.

The reamer is a kind of hole finishing tool used in drill press, lathe or by hand for reaming. The milling is used in miller, which has one or more teeth for rotary milling. It can specifically divided into face cutter, cylindrical cutter, square cutter, finger cutter, disc – shaped cutter, large flat cutter and so on. Relatively, the mill has broader applications. The reamer can be also divided into coarse and finishing types. Coarse type has fewer edges, larger chip space and has open spiral flutes points to prevent excessive coarse chips hinge and clogging; finishing type has more edges, leaves a small edge in order to ensure the quality of reaming. The specifications include 1:50, 1:20, and 1:5. The Turning tool is used for cutting metal. Welding tools, is the holder of ordinary steel with a carbide blade milling corresponding cutout, solder and copper brazed borax. The turning tool can be specifically divided into CNC tool, external turning tool, diamond turning tool, alloy turning tool and tungsten carbide turning tool.

Tungsten carbide valve needle is one of significant part of valve system, such as needle-valve hot runner nozzle. It has high hardness, high strength, high toughness and high regulation accuracy, especially for fiberglass plastic parts.Tungsten carbide valve needle has a sharp spool, mainly used in adjusting the air flow. Needle valve can withstand larger pressure than other types of valves, has good sealing property, so it is suitable for small flow, air or liquid medium with high pressure sealing. It is appropriate that combine the valve needle with pressure gauge, and usually the needle valve are made of threaded connection.

There are some advantages of tungsten carbide valve needle:
a. Cylinder, valve needle and nozzle with shaft design ensures smooth and reliable movement of the valve needle;
b. No cam, leverage, cylinder and nozzle embedded in the template and the overall structure is compact;
c. Simple connection, easy assembly replacement among parts;
d. After TiN treatment, tungsten carbide valve needle has better durability;
e. The inner channel surface has smooth transition, no dead material stagnation point, which is beneficial for refueling color change;
f. It can be suitable for diverse engineering plastics.

Tungsten carbide valve seat has excellent wear and corrosion resistance, which can be widely used in mining, construction, oil drilling, and tunneling and plays an important role in supporting spool, sealing and directing the fluid. It has many functions, such as:
1. Connecting the valve inlet and outlet piping;
2. Forming valve chamber and guiding the fluid in valve;
3. Fixing the valve operator;
4. Enduring the pressure of fluid inside of valve.

In addition, according to different structure, it can be divided into normal type, flexible type, combined spring, piston-type and special structure.
1. Normal: Under preload or fluid pressure ball valve seat and pressed, and seat materials to produce plastic deformation to achieve sealing. The sealing effect depends on the ability to seal the valve seat under the influence of fluid pressure or preload compensation sphere roundness and surface micro irregularities;
2. Flexible: By means of an elastic element, such as metal spring frame and springs, elastically deformed under preload or fluid pressure in order to compensate for changes in ambient conditions of temperature, pressure and effect on sealing performance;
3. Combined spring: Transverse cross-section along the circumference of the valve channel uniform compression spring or a thrust with only one disc springs, and always maintain the ball seat pressed to achieve the preload state;
4. Piston: The seat pushed to press the sphere and through plastic deformation of the seal ring obtain sealing;
5. Special structure: It includes internal or external adjustable type, bellow type, grease sealing type, dual promote type, modular type, etc.

Tungsten carbide die thimble is also known as putter, insert needle, holder needle, which plays an important role in separating the product from mold and conducting the light hole. And is an important component in mold and has been widely used in lathe, grinder and other mechanical equipments. There are some applications of tungsten carbide die thimble:
1. Generally used in separating the product from plastic mold;
2. Tungsten carbide die thimble can be also used in conducting light hole;
3. Mounted on a lathe or grinder, used to support the workpiece and the workpiece is rotated around its head conical metal rod;
4. Support the mold, such as insert needle (includes vaulted needle, standard needle and non-standard thimble).

Lathes, grinders thimble standard model: Fixed thimble standard is GB / T9204.1-1988, standard rotary thimble is JB / T3580-1998. Thimble and matching plastic mold design standards:
1. Less than 3mm should use two thimbles;
2. With the mast out of the top block, requiring top plate insert block 8 mm. Top block must have a fixed guide bushing;
3. Small top block can not be fixed with screw, design the pin for positioning;
4. Sheet R angle must be designed, and the thimble is the priority when the top sheet either thimble can be used;
5. In the mold can be used with the top piece can also be ejected with a thimble circumstances, give priority to thimble;
6 thimble through the knife left 20-25 mm;
7. Thimble plate gap between the left and right through the knife 0.5 mm;
8. The ejector pin must have a lower guide pin and a trash pin;
9. Thimble plate reset as much as possible to give priority to the top of the accessories;
10. To maximize the use of the top of the thimble;
11. Can be used to automatically lift off the premise of the product under the roof, try to avoid gas cap;
12. Core, cavity valve to design concentric (especially transparent products);
13. Mold design Carefully calculate the top of the distance, to avoid the lack of lead to the top of the trip;
14. Not the same product to carefully consider the top position and the top out of the way;
15. Cylinder top out of the mold cylinder to put the top of the needle board. 

Tungsten carbide guide bushing is also called drill bushing or mold bushing, which usually used with guide pin together and plays an important role in fixing and guiding. The general clearance is small, less than 0.05mm, more used in mold or some machines to ensure the cutting or drilling accuracy. Compared with bearing steel, tungsten carbide guide pin has better performance in guiding, durability and commutativity. It plays an important role in ensuring the accurate position and mold guiding. There are some funtion of tungsten carbide guide bushing and pin:
1. Connect the upper and lower guide device;
2. Maintain the clearance to reduce the bad effect of punching;
3. Endure lateral force to avoid the deviation, chipping and equipment damage or even personal safety;
4. Keep the accuracy and extend the service life by reasonable design.

According to  different applications, it can be divided into automotive mold guide pin, independent guide pin, mold with guide post, stripper plate with guide pin; according to guiding direction, it can be divided into sliding guide pin (SGP), Rolling guide pin (SRP); and it can be divided into handling type and pressing type according to  installation mode.In addition, it should be noticed that:
1. Before processing, it is necessary to check the diameter of bottom hole and determine the dimensions of boring bar and holes;
2. Choose the proper boring bar according to the depth of hole and the terrain or position;
3. Check the eccentricity to determine whether it can completer the processing;
4. The diameter of non-working part should be 5mm longer than the corresponding guide pin;
5. After the processing, measure the aperture and verticality according to the relevant standards.
6. Based on the allowable deflection and the lateral force determine the size of the guide pin
7. Based on the variation of the clearance and the arrangement of pin and bushing;
8. Based on the minimum clearance between guide pin and bushing determine the geometric tolerance.

Tungsten carbide guide roller has excellent wear and corrosion resistance, is located between pump and turbine wheel, which is an important response component of torque converter. It fixed in one direction on the guide wheel or guide wheel bushing by one-way clutch. There are some major funcions of tungsten carbide guide roller as follow:
1. Belt transmission: In the semi-angle of the cross transmission, guiding the direction of movement of the belt, so that the leading edge aligned with the center plane of the wheel width of the idler pulley;
2. Hydraulic transmission: Make the working fluid moment of momentum change, without absorbing mechanical energy output of rotating impeller;
3. As metal cutting machine parts: The parts for workpiece axial transmission and rotation in centerless grinding process.

In addition, we should notice that when using tungsten carbide guide roller:
1. The service life of guide roller does not depend on time, but judge combined with the processed material and the quality of cutting fluid;
2. Tighten wire, rise to the height of 300 or more, check the front and rear of molybdenum wire jitter before running. If the jitter is too large, it means some problems on guide wheel pr bearing. So double check and replace it if it needed;
3. The interval and slightly shake can only be used in the workpiece with lower precision requirements;
4. Check the cutting down of the workpiece, if the workpiece surface between the correct pulse width under the process of significantly roll marks or accuracy error, also expressed it is necessary to replace the guide wheels and bearings.
5. Do not beat the bearing when you are changing the guide roller, or it will has a bad effect on the service life of guide roller bearing if too large pressure.