Rough Machining the Pump Body with Solid CBN insert

Rough Machining the Slurry pump impeller with Halnn CBN insert

Rough Machining the Pump Casing with Halnn Solid CBN Insert

 Machine the double metal cylinder of drilling mud pump

Mud pump is also known as the heart in the drilling system. while the mud pumps cylinder is the important and easy wear out parts in mud pump fluid end, the cylinders life directly effect the mud pumps life. Moreover the working surface of the cylinder was contact with the gas which has high temperature and high pressure, there are piston ring running reciprocating motion on the surface, those require the cylinder of mud pump has a better sufficient strength and rigidity, and also must have high temperature resistance, corrosion, wear-resistant properties.

Part 1 The type and advantage of the drilling mud pumps cylinder:
At present, commonly there are those types of cylinder: single metal cylinder, double metal cylinder, ceramic liner, nickel-based alloy cylinder liners. Wherein the double metal cylinder is the most widely used one, also it is one which is the largest amount of mud pump fluid end components.

Double metal cylinder includes inner and outer cylinder, The outer cylinder was made of high-quality carbon steel hot press which molding, having a tensile strength greater than 900000psi. Inner cylinder was made of high chrome cast iron casting, hardness can reach more than HRC62 after the heat treatment, which can withstand pressure 7000psi from mud, so the requirement was more strictly with the surface and inner hole size of inner and outer cylinder.

Part 2 Processing technology and heat treatment of the double metal mud pump cylinder for drilling

1.Outer cylinder: Inspection of the raw material----process the rough----inner bores roughing----thermal loading (and inner sleeve thermal loading)----boring inside----finishing grinding--- finishing turning
2.Inner sleeve: centrifugal casting----annealing----roughing excircle----inner bores roughing---half finishing excircle----quenching----NDT---shrinkage fitting (with outer cylinder)
3.Heat treatment classifying: normalizing, annealing, quenching, tempering, shrinkage fitting(shrinkage fitting means burned at a temperature of 450 ℃ -500 ℃ for 5-6 hours, then 100% inspection and pressure  test after 24 hours cooling). You can choose a different heat treatments depending on the different manufacturers process technology.

Part 3 Most suitable materials for machining drilling double metal mud pump cylinder sleeve
At beginning, we said the hardness reach HRC62 or more after heat treatment, it has a high hardness and difficult to process, also requires a high dimensional accuracy. Currently people use carbide tool ,ceramic tools and CBN tools to machine the ferrous metal.

Why CBN tools is the best choice when people machine the drilling double metal mud pump cylinder sleeve, the reasons as follows:

(1) carbide cutting tools are only suitable for machining ferrous materials hardness HRC45 or less due to its performance;

(2) ceramic cutting tools suit for machining ferrous metal materials which hardness was between the HRC45 to HRC55, and finishing process which the machining allowance is smaller.

(3)As the hardness of the cubic boron nitride(CBN) tools is only to diamond tools’ ,They both called super-hard tools, there is a good effect to machining ferrous materials which hardness above HRC45 with CBN tools.
Through Halnn superhard material company’s steady effort more than ten years in this field, She become the best-known material processing tools brand, From Halnn was founded, she continued to provide the tools which were high-efficiency, high-quality, high-performance for the high hardness and difficult to machine tool materials in the field, She enjoyed a high reputation in the field of hard materials processing tool, she was the world-class leader.

Halnn superhard has the professional cubic boron nitride cutting tool for machining drilling mud pump cylinder, specific details as follows.

Part 4 Appliccation Case of Halnn superhard cubic boron nitride tools processing drilling mud pump cylinder liners parameters

Workpiece Name:	Cylinder liner of mud pump
Heat treatment	Surface hardening
Work piece material	High chromium cast iron:
Hardness	HRC60-65
Work piece dimension	Diameter:178mm,Thickness:5mm,Lenth:450~600mm
Machining parts:	The outer, chamfered
CBN Insert Grade	Halnn BN-S30
Arbor Model	CCLNR2525M1207
Inserts Model	CNMN120712-8S
Cutting parameters	Vc=90-120m/min, Fr = 0.25mm, ap=2mm
Durability	9pieces/edge

If you would like to know more details ,please feel free to contact with us halnntools@gmail.com ,whatsapp:+8618695866134

Halnn CBN cutting tools advantages for machining chilled cast iron compared with carbide and Ceramic cutting tools

Part 1 Introduction of Chilled cast iron

Chilled cast iron is that placed cold iron in the mold to accelerate the cooling rate of the casting obtained. Due to cooling speed of the cast iron surface layer which contact with the chilled cast iron, so cast iron belong to white in a certain part of the thickness, and this part has a higher hardness and better wear resistance; while the deeper part cast iron which away from the chilled, has a lower cooling rate and belong to gray cast iron; the transition region between the white and gray showed a mottled. Typical chemical composition of chilled cast iron: content :C3%~3.5%, Si0.5%~0.7%, Mn0.5%~0.7%, P<0.4%, S<0.07%.

The characteristic of chilled cast iron: a hard outer and tough inner outer, surface portion occurrent of white, hardness and wear resistance were greatly improved, the inside still remained the gray tissue to prevent overall embrittlement. Chilled cast iron used for be the part which there is non-abrasive under friction condition, in addition to the sliding parts also included varying degrees of rolling movement. The parts surface not only requested high hardness, good wear resistance, but also requires the work piece which machined has a sufficiently high strength and toughness, Generally, chilled was usually used in the manufacture rollers, wheels and other parts.

Such as the rolls which made of chilled cast iron rolls, based on the base structure of the white layer. Rolls can be divided into ordinary chilled cast iron rolls and alloy chilled cast iron rolls, alloy chilled cast iron roll also includes low-alloy chilled cast iron casting rolls , alloy rolls and high-alloy’s. The following is the cast iron images

Part 2 The reason which why it is difficult to machine the Chilled cast iron:

(1)Chilled cast iron is a typical materials which was hard and brittle, it has a high surface hardness. The unit cutting force can reach 3000MPa during roughing, the strong impact can easily cause vibration, increasing the tool’s wear.

(2) Chilled cast iron has high hardness and high thermal strength. Especially when machine the large parts , the cutting tool costs long working hours, the tools will have a high temperature, and cutter body prone to deformation or welding inserts met the phenomenon which welding opened. Make the tools broken.

(3) The surface structure of chilled cast iron is white, it was hard and brittle , when the tool cut in or cut out, easily prone to chipping, resulting in tools wasted or damaged.

(4)The chilled cast iron is often used to make a variety of rolls, the structure’s size was large , allowance is also large, a larger depth of cut and feed rate needed when turning, has a higher requirements of the tools strength and rigidity of the process system.

Part 3 How to choose the tool material to machine the chilled cast iron:
The surface layer’s hardness of the chilled cast iron can reach about HRC60, high hardness, brittleness, and there are many surface hard spots and sand, which is why the material is required for tool have a high red hardness, impact resistance, wear resistance, high bending strength, thermal conductivity Big.

The analysis of the tool material:

(1)Carbide Tool: Due to the characteristics of the material, carbide tools body has a hardness around HSD100, the workpiece can be machine when there is certain gap between the workpiece and the tools, so the range of suitable for machining ductile iron with low hardness (HSD70 less ). It is almost impossible to machine the chilled cast iron which hardness reached about HSD85 .

(2)ceramic tool: Because ceramic tools has brittleness nature, low transverse rupture strength, weak ability to withstand impact loads, so we can choose ceramic tools when machining hardness less than HRC55 or using a small amount of feed, but rough castings accompanied by trachoma generally, including sand casting defects, chipping easily happened when using ceramic tool. 

(3)Halnn cubic boron nitride cutting tools BN-K1 Brand

BN-K1 grades CBN tool has a better Cutting performance, hardness, fracture resistance and abrasion resistance, the tool can greatly improve the cutting efficiency of surface of chilled cast iron, this tools cutting effect is significantly higher than other cutting tool materials. BN-K1 grades cubic boron nitride cutting tools has a higher hardness, a better wear resistance than carbide tools. CBN tools has the same disadvantage of brittleness like ceramic tools, While BN-K1 grades tools using non-metallic binder and cubic boron nitride powder production, the tool adds toughness, impact strength performance, compared to ceramic tools, has a excellent chipping resistance to damage. Your can get the BN-K1 grades tools advantage and which material can be machined from the following table.

BN-K1 grades tools advantage and which material can be machined

Tools Grade	Material Machined	Performance advantages	Application industry
BN-K1	Chilled Cast iron, High alloy Cast iron, heat-resistant alloy, high manganese steel	Good crash damage resistance and excellent high temperature resistance to fracture	High hardness alloy cast iron roll, industrial pump parts, alloy wear resistant castings

The effect comparison between BN-K1 brand tool and ceramic tool(as followed table)   

Except for machining the chilled cast iron roll,BN-K1 can also machine chilled cast iron parts ,such as: valve lifters, valve tappet, etc; but also for other high-alloy cast iron flywheel parts, industrial pumps, cylinder and so on; also suitable heat-resistant high manganese steel and other steel parts processing. When machining those high hardness casting parts, BN-K1 tools can exhibit excellent than Carbide cutting tool material and ceramic tools material on chipping damage resistance and high temperature fracture resistance.
Part 4 The case of Halnn superhard materials company’s BN-K1 brand tools process the chilled cast iron rolls:
When turning the chilled cast iron rolls, the rolls has a higher hardness, roughing roll usually has pores, trachoma, including sand casting, defects the tools impact resistance, heat resistance, wear resistance demanding. We should choose BN-K1 to process this type rolls. This brand maintaining excellent wear resistance and hardness like CBN tools, it also has a better impact toughness, not collapse damage, can pull roll shortage roughing,BN-K1 is the most high-impact hardness of superhard cutting tool grades currently. This tools can withstand a greater depth of cut and metal removal rate.
Application Case as follows:

Processing the cast iron roll
Rolls Hardness	HSD80
Cutting Parameters	ap=4mm;Fr =1mm/r; Vc =55m/min
insert Grade	Halnn BN-K1	Other Ceramic insert
Tools material Feed rate	1mm/r	0.5 mm/r
Lifetime per Tip	3piece/point	0.5piece/point

From the table, We can get:

With the same cutting speed and back engagement of BN-K1 grades CBN cutting tools and a European brand of ceramic inserts,BN-K1 CBN tools feed rate is twice higher than the ceramic tools and six times lifetime than ceramic tools,BN-K1 improve processing efficiency, saving processing time.

If you would like to know more details ,please feel free to contact with us halnntools@gmail.com ,whatapp:+8618695866134

Hardened steel common materials heat treatment procedure

Because of excellent use performance of hardened steel widely used in transportation, metallurgy, wind power, mold, construction machinery and other fields. Different industries using different materials, heat treatment procedures are also not the same. Here's a brief description about heat treatment process aiming at different industries of hardened steel materials.

1.Transportation industry common materials heat treatment process

Some automobile parts after the heat treatment process will obtain excellent usage performance. such as automobile parts gears, gear shafts, crankshafts, etc. Gearbox require high performance, so often use 20CrMo or 20CrMoTi as for the main material of gear. 20CrMo gear heat treatment process includes: normalizing, carburizing, quenching, tempering.

Normalizing: 20CrMo gear normalizing temperature at 930~950℃, in order to promote austenite homogenization, increasing austenite super cooled stability;

Carburizing: gas carburizing, at a temperature of 900~920℃, to 0.15~0.2mm/h calculate heat preservation time, the heating temperature does not exceed 920℃, in order to avoid coarse grains.

Quenching and tempering: quenching temperature between 820~850℃, after heat preservation using oil cooling, 180℃ low tempering.

Through hardened steel gear hardness after heat treatment at HRC55 or more, not only to obtain a higher hardness, strength, wear resistance, but also strong fatigue resistance and strong fracture resistance, and can working at high speed state.

2. Bearing industry common materials heat treatment process

Because of some bearing operating in harsh environments, on the processing performance of the bearing demanding, it is required to have good performance and long life. Therefore we often use 40Cr or GCr15 as for the main material of bearing. Bearing through heat treated to obtain a higher hardness, wear resistance and good toughness, fatigue resistance. Bearing heat treatment process including: annealing, quenching, tempering.

Annealing: GCr15 steel annealing temperature is 780~810℃,after forgings a special heat treatment, the annealing temperature should reduce 10~20℃.

Quenching and tempering: GCr15 martensite under normal circumstances, the quenching temperature is about 840℃, generally not more than 850℃. The tempering temperature is controlled at 150~160℃ can meet the requirements.

After heat treatment, hardened steel bearings hardness in general HRC60 or more, not only high hardness, good wear resistance, and service life is improved.

3. Hardened steel parts machining after the heat treatment

Hardened steel hardness is over HRC50 after heat treatment, such as automotive gear hardness is HRC58~63,GCr15 bearing hardness is HRC60~62, which is a big problem for machinery manufacturers. It is necessary to ensure the quality of hardened steel parts, but also to ensure the efficiency of hardened steel parts. The initial grinding can not meet requirements of processing efficiency of the machinery manufacturers, can only come from other places to find a solution.

With the continuous development of the cutting tool industry, eventually developed hard turning cutting tool material, which can effectively solve the problem of low grinding efficiency. Hard turning cutting tool materials have coated carbide cutting tools, ceramic cutting tools and cubic boron nitride cutting tools, simply select the appropriate cutting tool materials to improve the processing efficiency of hardened steel parts.

Halnn superhard developed non-metallic adhesive cubic boron nitride cutting tools, for over HRC45 hardened steel parts can be effectively solve the problem of low processing efficiency.

Processing automobile gear inner bore, end face optional BN-H20 grades and BN-H21 grades CBN cutting tools (intermittent machining conditions);

Processing GCr15 bearing inner bore, cylindrical choose BN-H11 grades CBN cutting tools (continuous cutting);

Processing large pieces of hardened steel gears gear face, optional BN-S20 grades CBN cutting tools (strong interrupted cutting conditions).

If you have more questions ,please feel free to contact with us halnntools@gmail.com ,whatsapp:+8618695866134

Environmental and Efficient---Halnn Superhard constantly chasing the aim

Halnn Superhard as a leader in professional hard materials processing tool, we have been adhering to the "Dedication, Innovation, Efficiency, Cooperation" business philosophy, in strict accordance with the proportion component of materials to manufacturing Cutting Tools. And we adopt professional high-end machines at high temperature and pressure conditions. It not only can meet high speed cutting, but also can realize efficient processing (high efficiency and high quality).

With following environmental concept, without cutting fluid, reduce environmental pollution. In Ferrous metal field, Halnn Superhard CBN grades cutting tools are widely used, such as BN-S20 cubic boron nitride inserts which is widely used in hardened steel, cast steel, forged steel etc.

Our company cubic boron nitride cutting tools can realize a large margin, interrupted turning and strong interrupted machining. For strong interrupted machining, BN-S20 grades CBN inserts machining gear tooth surface (strong intermittent cutting), With continuous impact state, the cutting parameters as follows:

Cutting Depth ap=2.5mm,Feed Rate Fr=0.12mm/r,Cutting Speed: Vc=90m/min

Processing effect: Cutting depth of BN-S20 is 2 times of ceramic inserts, cutting tools life is about 16 times of single-edged ceramic cutting tool, and no chipping.

Halnn superhard developed a cutting tool products will go through practice of a long period. Selling products after determining to achieve performance of high-quality, high-efficiency. For example ,a roll factory in one of the provience in China, originally used carbide cutting tools, cutting tool is changed frequently in processing, not only affects the processing efficiency and also surface quality is not good.

Our company aiming at the above problems, we recommend BN-S20 cubic boron nitride inserts, this cutting tool belongs to solid CBN inserts, non-metallic (ceramic) as a binder to improve the cutting tool itself impact toughness and fracture resistance.

Cutting Parameters:Depth of cut ap=4~7mm,cutting speed can arrive 90m/min.

Processing effect: Not only cutting speed is higher than the carbide tools, but also single blade life is 10 times of carbide cutting tools. Significantly lower cutting tool fees, production costs are reduced, overall benefits have been greatly improved.

Halnn Super hard not only provide standard types products for clients, but also for non-standard products "Tailored." Such as processing cutting tools of inner hole, the inner hole the smallest diameter generally is 16mm, but some customers work piece inner hole is only 10mm, Halnn Superhard will be based on the actual situation of users, customized non-standard cutting tool.

With the development of modern technology, Halnn Superhard constantly advance with the times to provide customers with complete solutions and efficient cutting tool products, we are committed to making the world no longer difficult to processing materials.

If you would like to know more details,please feel free to contact with us halnntools@gmail.com ,whatsapp:+8618695866134