Understanding the Phillips Drive: The Ultimate Guide to Screw Selection

phillips drive screw

Are you tired of struggling with different types of screws and their confusing drive styles? Look no further! In this ultimate guide, we will demystify the Phillips drive and help you understand its importance in screw selection. Whether you’re a DIY enthusiast or a professional builder, having a thorough knowledge of screw drives is essential. The Phillips drive, known for its cross-shaped indentation, is one of the most widely used drive styles in the world. It offers excellent torque transfer, reducing the risk of slippage and ensuring a secure fastening. But understanding the Phillips drive is not just about knowing its shape; it’s about knowing when and where to use it. From woodworking projects to electrical installations, this guide will equip you with the knowledge to choose the right screws for any task. So, get ready to level up your screw game and unlock the full potential of the Phillips drive!

Different Types of Screw Drives

When it comes to screws, there is a wide variety of drive styles to choose from. Each drive style has its own unique features and advantages. Before we dive into the specifics of the Phillips drive, let’s take a quick look at some other common screw drive types:

1. Flathead Drive: Also known as a slotted drive, this is one of the oldest and simplest screw drive types. It features a single straight slot that requires a flathead screwdriver to tighten or loosen the screw. While flathead screws are still used in some applications, they are prone to slippage and are not as secure as other drive types.

2. Torx Drive: The Torx drive, also known as a star drive, consists of a six-pointed star-shaped pattern. It offers excellent torque transfer and is less likely to strip compared to other drive types. Torx screws are commonly used in automotive, electronics, and machinery applications.

3. Square Drive: The square drive, also known as a Robertson drive, features a square-shaped recess. It provides good torque transfer and reduces the risk of cam-out, making it popular in woodworking and construction applications.

4. Hex Drive: The hex drive, also known as an Allen drive, requires a hex key or Allen wrench to tighten or loosen the screw. It offers high torque transfer and is commonly used in furniture assembly, bicycle repairs, and machinery applications.

Now that we’ve covered a few different screw drive types, let’s explore the history and development of the Phillips drive.

The History and Development of the Phillips Drive

The Phillips drive was invented by Henry F. Phillips in the 1930s as a solution to the problems associated with flathead screws. Flathead screws were prone to slippage and required significant force to tighten or loosen. Phillips wanted to create a drive that would provide a more secure and efficient fastening method.

After years of experimentation, Phillips developed the Phillips drive, which features a cross-shaped indentation. This design allows the screwdriver to engage more effectively with the screw, reducing the risk of slippage and making it easier to drive the screw into various materials.

The Phillips drive quickly gained popularity in the automotive industry due to its ability to provide consistent torque transfer and prevent damage to the fasteners. It became the standard drive type for many American-made cars and helped revolutionize assembly line production.

Advantages and Disadvantages of the Phillips Drive

The Phillips drive offers several advantages that make it a popular choice for a wide range of applications. Here are some key benefits of using the Phillips drive:

1. Torque Transfer: The design of the Phillips drive allows for efficient torque transfer, ensuring a secure fastening without slippage. This is particularly important in applications where a strong and reliable connection is necessary.

2. Easy Centering: The cross-shaped indentation of the Phillips drive makes it easier to center the screwdriver on the screw head, reducing the risk of stripping the screw or damaging the surrounding material.

3. Common Availability: Phillips screws and screwdrivers are widely available in hardware stores, making them easily accessible for various projects.

Despite its many advantages, the Phillips drive does have some limitations:

1. Cam-out: Due to the design of the Phillips drive, it is susceptible to cam-out, which occurs when the screwdriver slips out of the screw head during tightening or loosening. This can lead to stripped screws or damaged fasteners.

2. Limited Torque: While the Phillips drive offers good torque transfer, it may not be suitable for applications that require high torque levels. In such cases, alternative drive styles may be more appropriate.

Now that we’ve discussed the advantages and disadvantages of the Phillips drive, let’s move on to understanding how to choose the right screw drive for your project.

How to Choose the Right Screw Drive for Your Project

Choosing the right screw drive for your project involves considering several factors, including the material being fastened, the torque requirements, and the application itself. Here are some guidelines to help you make an informed decision:

1. Material Compatibility: Different screw drives perform better in specific materials. For example, the Phillips drive is well-suited for wood applications, while the Torx drive is preferred for metal and plastic applications. Consider the material you’re working with and choose a screw drive that offers optimal performance in that material.

2. Torque Requirements: Determine the amount of torque required for your project. If you’re working on a high-torque application, you may want to choose a drive style that can handle the load without slipping or stripping.

3. Familiarity and Availability: Consider your familiarity with different screw drives and the availability of screws and screwdrivers in your area. Choosing a drive style that you are comfortable working with and can easily find replacements for will make your project more efficient.

By taking these factors into account, you can confidently select the right screw drive for your specific project requirements. Now, let’s explore some common applications of the Phillips drive.

Common Applications of the Phillips Drive

The Phillips drive is widely used in various industries and applications, thanks to its reliable torque transfer and ease of use. Here are some common applications where you’re likely to encounter the Phillips drive:

1. Woodworking: The Phillips drive is a popular choice for woodworking projects due to its ability to provide a secure and flush fastening. It is commonly used for furniture assembly, cabinetry, and general woodworking tasks.

2. Electrical Installations: The Phillips drive is often found in electrical installations, such as light fixtures, electrical outlets, and switch plates. Its ease of use and compatibility with electrical screwdrivers make it a convenient choice for electricians.

3. Automotive: While the automotive industry has transitioned to other drive types in recent years, the Phillips drive is still used in certain applications, such as interior trims and panels.

4. DIY Projects: The Phillips drive is a go-to choice for DIY enthusiasts tackling various projects around the house, including hanging shelves, assembling furniture, and installing hardware.

These are just a few examples of the many applications where the Phillips drive shines. Now, let’s dive into some tips for using Phillips screws effectively.

Tips for Using Phillips Screws Effectively

To ensure successful and hassle-free screwing, here are some tips to keep in mind when working with Phillips screws:

1. Use the Right Size: Select a screwdriver that matches the size of the Phillips screw head. Using the wrong size can damage the screw head or lead to cam-out.

2. Apply Steady Pressure: Maintain a firm grip on the screwdriver and apply steady pressure while driving the screw. This will help prevent the screwdriver from slipping out of the screw head.

3. Pre-Drill Pilot Holes: When working with hardwood or dense materials, pre-drilling pilot holes can prevent the wood from splitting and make it easier to drive the screws.

4. Avoid Over-Tightening: While it’s important to ensure a secure fastening, over-tightening Phillips screws can cause the screw head to strip or damage the surrounding material. Use caution and stop tightening once the screw is firmly in place.

By following these tips, you can maximize the effectiveness of Phillips screws in your projects. However, it’s essential to note that the Phillips drive is not the only option available. Let’s explore some Phillips drive alternatives and their uses.

Phillips Drive Alternatives and Their Uses

While the Phillips drive is widely used, there are several alternatives that offer unique advantages for specific applications. Here are a few notable Phillips drive alternatives:

1. Pozidriv Drive: The Pozidriv drive is similar to the Phillips drive but features additional cross-shaped indentations. This design reduces the risk of cam-out and provides better torque transfer. Pozidriv screws are commonly used in furniture assembly, cabinetry, and other applications where high torque is required.

2. Frearson Drive: The Frearson drive, also known as the Reed and Prince drive, is similar to the Phillips drive but has a sharper point and a narrower slot. It offers better torque transfer and is commonly used in marine applications and woodworking.

3. Tri-Wing Drive: The Tri-Wing drive features three wings radiating from the center, forming a triangular shape. It is commonly used in electronic devices and appliances to prevent tampering.

4. One-Way Drive: The One-Way drive features slanted slots that allow for easy installation but prevent removal. It is often used in public spaces and to secure valuable items.

Each of these drive alternatives has its own unique features and applications. Consider the specific requirements of your project to determine if a Phillips drive alternative may be a better fit.

Tools and Techniques for Working with Phillips Screws

To ensure success when working with Phillips screws, it’s essential to have the right tools and utilize the proper techniques. Here are some tools and techniques that can help you work effectively with Phillips screws:

1. Screwdriver Selection: Choose a high-quality screwdriver that fits the Phillips screw head securely. A properly fitting screwdriver will minimize the risk of slipping or damaging the screw head.

2. Magnetic Screwdrivers: Magnetic screwdrivers can be a game-changer when working with small screws or in tight spaces. They help hold the screw securely in place, making it easier to drive and preventing accidental drops.

3. Impact Drivers: For larger projects or applications that require high torque, consider using an impact driver. Impact drivers deliver powerful rotational force, making it easier to drive screws quickly and efficiently.

4. Screw Starter: A screw starter, also known as a self-centering bit, can help you accurately position the screw in the desired location. It ensures that the screw starts straight and reduces the risk of stripping or damaging the surrounding material.

By utilizing the right tools and techniques, you can work with Phillips screws more effectively and achieve better results in your projects.

Conclusion

In conclusion, the Phillips drive is a versatile and widely used screw drive that offers excellent torque transfer and secure fastening. Understanding the Phillips drive and its applications is essential for anyone working with screws, whether it’s for woodworking, electrical installations, automotive projects, or DIY tasks. By following the tips and guidelines outlined in this guide, you can confidently select and use Phillips screws effectively. Remember to consider the material compatibility, torque requirements, and availability of screws and screwdrivers when choosing the right drive type for your project. With the right knowledge and tools, you can unlock the full potential of the Phillips drive and elevate your screw game to new heights.

A Comprehensive Guide to DIN912 Hex Socket Cap Screws and Their Specifications

cap screws article

Introduction

Hex socket cap screws are one of the most commonly used types of fasteners in industrial and engineering applications. These screws are known for their hexagonal head with an internal socket, which can be tightened or loosened using an Allen key or a hex wrench. DIN912 is the standard specification for hex socket cap screws, and this screw is available in a variety of materials, sizes, and thread types.

Materials

DIN912 hex socket cap screws are available in a range of materials to suit various applications. Stainless steel screws are the most popular type and are ideal for applications that require high resistance to corrosion. They are commonly used in marine and coastal environments where exposure to saltwater can cause other types of fasteners to corrode quickly. Alloy steel screws are known for their high tensile strength and are used in high-stress applications such as construction and heavy machinery. Nylon screws are lightweight and non-conductive, making them ideal for applications that require electrical insulation.

Sizes and Threads

DIN912 hex socket cap screws are available in a range of sizes and thread types. The thread diameter of the screw ranges from M1.4 to M24, with both metric and imperial measurements available. The smaller diameter screws are typically used for precision instruments and small electronic devices, while larger screws with thread diameters up to M24 are used in heavy machinery and construction applications. The thread types include both left-handed and right-handed threads, allowing for even more versatility in various applications.

Left-Handed and Right-Handed Threads

In addition to the range of sizes and thread types available for DIN912 hex socket cap screws, there are also left-handed and right-handed thread options. Left-handed threads are threads that turn in a counter-clockwise direction, while right-handed threads turn in a clockwise direction. Left-handed threads are less common and are often used in specialized applications where there is a need for a reverse thread.

Left-handed threads can be useful in situations where the screw is under constant vibration or in applications where a reverse torque is applied to the screw. In these cases, a left-handed thread can help prevent the screw from becoming loose. Additionally, left-handed threads can be used in applications where there is a need to prevent the screw from unscrewing due to the direction of motion.

Right-handed threads are the most commonly used type of thread in DIN912 hex socket cap screws. They are used in a wide range of applications and are suitable for most general-purpose fastening needs.

Applications

Hex socket cap screws are used in a wide variety of industrial and engineering applications. They are commonly used to secure two or more objects together, with the hexagonal head providing a secure grip that prevents the screw from slipping or stripping. The internal socket allows for easy tightening and loosening in tight spaces, making hex socket cap screws ideal for assembly and disassembly applications.

In the automotive industry, hex socket cap screws are used to secure various components of the vehicle together. They are commonly used in engine assemblies, suspension systems, and brake systems. In the aerospace industry, these screws are used in the assembly of aircraft engines and airframes. The high-strength properties of alloy steel screws make them ideal for use in aircraft applications where safety is critical.

In the construction industry, hex socket cap screws are used to secure building components together. They are commonly used in steel frame construction, as well as in the assembly of pre-fabricated buildings. In the electronics industry, hex socket cap screws are used to secure printed circuit boards (PCBs) and other electronic components together. Nylon screws are commonly used in electronic applications where electrical insulation is required.

Conclusion

In conclusion, DIN912 hex socket cap screws are versatile and reliable fasteners that can be used in a wide range of industrial and engineering applications. The choice of material, size, and thread type depends on the specific application, but with the right selection, DIN912 screws can provide a secure and reliable connection that can withstand the stresses of the environment in which they are used. From the automotive industry to aerospace, construction, and electronics, hex socket cap screws are a critical component in various applications where safety, strength, and reliability are paramount.

What Are the Types of Bolts?

What Are the Types of Bolts

Hexagon Head Bolts

EN3008 – 1998 Aerospace Series Bolts, Hexagon Head, Relieved Shank, long Thread, In Heat Resisting Nickel Base Alloy NI-P100HT (Inconel 718)-Classification: 1275 MPa (At Ambient Temperature)/650°C

DIN601 M5 to M52 hexagon head bolts—Product grade C

UNI5737

UNI 5737 Hexagon Cap Screw, Partially Threaded Shank, ISO Metric Coarse Thread Pitch – Product Grade A

DIN931 Hexagon head bolts grades A and B partially threaded (Equivalent standards: ISO4014-1999, ISO4014-2011)

ANSI/ASME B 18.6.7M Metric hexagon head screws

EN24015 Hexagon Head Bolts-Product Grade B-Reduced Shank (Shank Diameter ≈ Pitch Diameter)

BS 3692 Metric Precision Hexagon Bolts

BS 4190 Iso Metric Hexagon Head Bolts – Faced Under Head Or Faced Under Head And Turned On Shank

AS 1559 ISO Metric Hot-dip Galvanized Hexagon Bolts For Tower Construction

ASME B 18.2.1 Heavy Hex Screws

BS 1981 Plain Hexagon Head Screws

Hexagon Bolts with Flange 

Round Head Bolts

Countersunk Head Bolts

Square Head Bolts

Eye Bolts

T-head Bolts

U Bolt

Foundation Bolts

Wheel Bolt/12-Point Screws

Steel Hexalobular Head Bolts With Flange

Torx Screwdriver Size Chart

Six-LobeA (mm)B (mm)R1 (mm)R2 (mm)C (mm)
T51.481.070.30.13
T61.751.270.360.16
T72.061.490.420.19
T82.391.730.490.220.6
T92.571.860.530.23
T102.822.030.570.250.8
T153.352.410.690.291
T203.942.830.830.331.4
T254.523.240.890.411.8
T275.083.641.050.432
T305.634.051.160.482.3
T406.764.841.40.582.6
T457.925.651.720.643.2
T508.946.451.780.813.6
T5511.338.12.460.924.6

Screwdriver head type classification

The use of screws is naturally inseparable from screwdrivers, and there are actually many types of screwdrivers. understanding with them will help us to live and work better.

According to different head types, screwdrivers can be divided into slotted, Phillips, Pozidriv, star, square, hexagon, Y head, etc. Among them, the slotted and Phillips are the most commonly used in our lives, and they are often used for furniture screws. . It is used for installation and maintenance. It can be said that a screwdriver is used as long as there are screws. Hexagonal heads are not used much. Hexagonal wrenches are commonly used. For example, many screws on some machines are equipped with hexagonal holes, which is convenient for multi-angle force. There are not many large star-shaped ones. Small star-shaped ones are often used to dismantle and repair mobile phones, hard drives, notebooks, etc. We call small screwdrivers a clock and watch bits, commonly used star-shaped T6, T8, cross PH0, PH00, etc.

SLOTTED:  1.0, 1.5, 2.0, 3.0

PHILLIPS: PH000PH00PH0PH1PH2PH3, the smaller the one in the front

POZI 

TORX:  Commonly used specifications T3T4T5T6T7T8T9T10T15T20T25T27T30T40T45T50

SQUARE

HEXGONAL:  H1.5, H2.0, H2.5, H3.0, H4, etc.

M-shaped (U-shaped, fork-shaped): M2.6 (the most common U-shaped screwdriver)

Y shape: Y2.0, Y3.0

▲shape:2.0、2.3

★shape: 1, 2

The bit of a high-quality screwdriver is not made of cold-headed steel for screws but is made of spring steel with relatively high hardness. A good screwdriver should be hard and not brittle. When the opening of the screw head becomes bald and slippery, you can hit the screwdriver with a hammer to make the screw groove deeper to facilitate the removal of the screw. The screwdriver should be undamaged; screwdrivers are often used. To pry things, you must have a certain degree of toughness and not bend or bend. In general, it is hoped that the hardness of the screwdriver head is greater than HRC60, and it is not easy to rust

CS

Mainly refers to steel whose carbon mass fraction is less than 2.11% and does not contain specially added alloying elements. Sometimes called plain carbon steel or carbon steel. The higher the carbon content, the higher the strength and the lower the plasticity (toughness). 45# carbon steel belongs to a kind of high-quality carbon steel (with low phosphorus and sulfur content), which is widely used in general tool materials.

Cr-V

Chromium vanadium steel is an alloy tool steel with chromium (Cr) and vanadium (V) alloy elements added. Its comprehensive strength and toughness are better than carbon steel, and it is suitable as an ideal material for high-quality tools. Such as wrenches, sockets, screwdrivers, etc.

Cr-Mo

It is an alloy of chromium (Cr), molybdenum (Mo), iron (Fe), and carbon (C). It has excellent impact resistance, excellent strength, and toughness, and overall performance is better than chrome vanadium steel. Suitable for making screwdrivers, etc.

S2

It is an alloy of carbon (C), silicon (Si), manganese (Mn), chromium (Cr), molybdenum (Mo), and vanadium (V). Excellent impact-resistant tool steel with excellent strength and toughness, high-end tool steel, overall performance is better than chromium-molybdenum steel. For example, screwdriver, Allen wrench, etc.

What are the fasteners including?

Screws, usually used alone (sometimes with washers), generally to fasten or tighten the role, should be screwed into the internal threads of the body

Bolts  Machine parts, cylindrical threaded fasteners with nuts. A class of fasteners consisting of two parts: a head and a thread (a cylinder with external thread), to be fitted with a nut, for fastening the connection of two parts with a through-hole

Nuts, The nut connects the bolt or screw together to play a fastening role in the parts.

Wood screws, used for screwing into the wood for joining or fastening purposes

Self-tapping screws, the working screw holes that match the self-tapping screws do not need to be tapped in advance, and the internal threads are formed while screwing in the self-tapping screws.

Studs, A type of fastener without a head and with external threads on both ends only

Retaining Ring is mainly used to position, lock, or stop the part on the shaft or in the hole.

Washers, the part that is padded between the connected parts and the nut. Generally, flat-shaped metal ring used to protect the surface of the connected parts from nut abrasion, disperse the pressure of the nut on the connected parts

Rivet has a head and the rod is not threaded. When used, the rod is inserted into the hole of the connected part, and then the end of the rod is riveted tightly to play a connecting or fastening role.

Pin, usually used for positioning, also for connecting or locking parts, and as overload shearing elements in safety devices

How are the screws made?

Screw manufacturing process flow including

feed-in →material inspection→heading→threading→plating-baking→ QA→packaging→shipping

How to make the screw head?

Forging can be classified according to the processing

  1. Cold Heading:   High production efficiency, suitable for producing small screws
  2. Hot forging:  Low production efficiency, suitable for producing large screws >M16

Cold heading 

Hot forging

Thread rolling: High production efficiency, low cost, suitable for mass production

Heat Treatment:

Heat treatment is the process of heating or cooling material in order to obtain desired properties and other conditions.

Self-tapping screws need to be carburized to obtain a very hard surface for thread tapping and forming or cutting. Usually, the surface hardness of self-tapping screws is HV450Min.

Surface treatment:

The process of forming a cover layer on the surface of the workpiece by certain methods is called surface treatment, the purpose of which is to give the product surface aesthetic and anti-corrosion effect on the surface of the product.

  1. Plating: The part to be plated is immersed in an aqueous solution containing the metal compound to be deposited, and an electric current is passed through the plating solution to precipitate and deposit the plated metal on the part. Through the plating solution, the plated metal is precipitated and deposited on the part. General electroplating has galvanization, copper, nickel, chromium, copper-nickel alloy, and so on. Chromium, copper-nickel alloy, etc. Sometimes blackening (bluing), phosphating, etc. are also included. 
  2. Hot dip galvanizing: done by immersing carbon steel parts in a bath of dissolved zinc at a temperature of about 510°C. The result is that the iron-zinc alloy on the surface of the product gradually turns into passivated zinc on the surface of the product. The result is a gradual transformation of the iron-zinc alloy on the surface of the steel part into passivated zinc on the exterior surface of the product.
  1.  Mechanical plating: by plating the particles of metal to impact the surface of the product, and cold welding the coating to the surface of the product

 At present, there are three main materials of carbon steel, stainless steel, and brass in the market for standard parts. 

1. Carbon steel

a. Low carbon steel: domestic is usually called A3 steel. Foreign basically called 1008, 1015, 1018, 1022, etc. Mainly used for 4.8-grade bolts and 4-grade nuts, small screws, and other products without hardness requirements.

b. Medium carbon steel: domestic usually called No. 35, No. 45 steel, foreign basic called 1035, CH38F, 1039, 40ACR, etc. Mainly used for 8-grade nuts, 8.8-grade bolts, and 8.8-grade hexagonal products.

c. High carbon steel: basically not used in the market at present.

d. Alloy steel: add alloy elements to plain carbon steel to increase some special properties of steel

2. Stainless steel

By grade mainly SUS302, SUS304, SUS316. its good heat resistance, good corrosion resistance, good weldability

3. Brass

Commonly used materials for brass … zinc-copper alloy. The market mainly uses H62, H65, H68 brass as standard parts.

Hardness Grade:

The grade of bolts for steel structure connection is divided into more than 10 grades, such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9.    

Among them, 8.8 grade and above bolts are made of low carbon alloy steel or medium carbon steel and heat-treated (quenched and tempered), commonly known as high-strength bolts, and the rest are commonly known as ordinary bolts.

HEX NUT DIMENSIONS

Hex nut dimensions metric with different materials Brass, stainless steel. carbon steel, nylon

HEX NUT DIMENSIONS
Thread Size
          d
M1M1.2M1.4M1.6M1.7M2M2.3M2.5M2.6M3M3.5M4M5M6(M7)M8
PPitchPitch
Fine thread
Fine thread
mmax=nominal size
min
mwmin
smax=nominal size
min
min
*
per 1000 units ≈ kg
0.250.250.30.350.350.40.450.450.450.50.60.70.8111.25
///////////////1
////////////////
0.811.21.31.41.61.8222.42.83.2455.56.5
0.550.750.951.051.151.351.551.751.752.152.552.93.74.75.26.14
0.440.60.760.840.921.081.241.41.41.722.042.322.963.764.164.91
2.5333.23.544.5555.5678101113
2.42.92.93.023.383.824.324.824.825.325.826.787.789.7810.7312.73
2.713.283.283.413.824.324.885.455.456.016.587.668.7911.0512.1214.38
0.030.0540.0630.0760.10.1420.20.280.720.3840.5140.811.232.53.125.2
Thread Size
           d
M10M12(M14)M16(M18)M20(M22)M24(M27)M30(M33)M36(M39)M42(M45)M48
PPitchPitch
Fine thread
Fine thread
mmax=nominal size
min
mwmin
smax=nominal size
min
min
*
per 1000 units ≈ kg
1.51.75222.52.52.5333.53.5444.54.55
11.51.51.51.521.5222233333
1.251.25//21.52/////////
8101113151618192224262931343638
7.649.6410.312.314.314.916.917.720.722.724.727.429.432.434.436.4
6.117.718.249.8411.4411.9213.5214.1616.5618.1619.7621.9223.5225.927.529.1
17192224273032364146505560657075
16.7318.6721.6723.6726.1629.16313540454953.858.863.168.173.1
18.921.124.4926.7529.5632.9535.0339.5545.250.8555.3760.7966.4471.376.9582.6
11.617.32533.349.464.479110165223288393502652800977
Thread Size
          d
(M52)M56(M60)M64(M68)M72(M76)M80(M85)M90M100M110M125M140M160
PPitchPitch
Fine thread
Fine thread
mmax=nominal size
min
mwmin
smax=nominal size
min
min
*
per 1000 units ≈ kg
55.55.566//////////
344446666666666
/////44444444//
424548515458616468728088100112128
40.443.446.449.152.156.159.162.166.170.178.185.897.8109.8125.5
32.334.737.139.341.744.947.349.752.956.162.568.678.287.8100
80859095100105110115120130145155180200230
78.182.887.892.897.8102.8107.8112.8117.8127.5142.5152.5177.5195.4225.4
88.2593.5699.21104.86110.51116.16121.81127.46133.11144.08161.02172.32200.57220.8254.7
170196216248
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