45# is generally the most widely used and can be used to make shaft sleeve parts;
The mechanical properties of 40Cr and 20Cr are better than those of 45# from the occasion of higher structural strength requirements.
1Cr 18Ni9 is stainless steel, which is suitable for manufacturing valves and cleaning parts.
The common materials of shaft are () and () steel and cast iron,,,
Processing common materials and instructions? Commonly used materials are divided into two types: metal processing. Hardness of nonmetallic materials (such as ceramics and plastics). ) range from large to small: stainless steel >; Cast iron > copper >: Let me talk about some commonly used aluminum, which I hope will be useful to you: 1, 45- high quality carbon structural steel, which is the most commonly used medium carbon quenched and tempered steel. Main features: The most commonly used medium carbon quenched and tempered steel has good comprehensive mechanical properties, low hardenability and is easy to crack after water quenching. Small parts should be tempered and large parts should be normalized. Application example: it is mainly used to manufacture high-strength moving parts, such as turbine impeller and compressor piston. Shaft, gear, rack, worm, etc. Welded parts shall be preheated before welding and annealed after welding. 2.Q235A(A3 steel)-the most commonly used carbon structural steel. Main features: high plasticity, toughness, weldability, cold stamping performance, certain strength and good cold bending performance. Application example: widely used in general requirements of parts and welded structures. Such as tie rods, connecting rods, pins, shafts, screws, nuts, ferrules, brackets, brackets, building structures, bridges and the like. There is almost no pressure. 3, 40Cr-one of the most widely used steel grades, belonging to alloy structural steel. Main features: it has good comprehensive mechanical properties after tempering, low-temperature impact toughness, low notch sensitivity, good hardenability, high fatigue strength in oil cooling, moderate cold bending plasticity in water cooling, good machinability after tempering or tempering, but poor weldability and easy cracking. Preheat to 100 ~ 150℃ before welding. Application example: after quenching and tempering, it can be used to manufacture medium-speed and medium-load parts, such as machine tool gears, shafts, worms, spline shafts, thimble sleeves, etc. After quenching and high-frequency surface quenching, it can be used to manufacture high-hardness and wear-resistant parts, such as gears, shafts, spindles, crankshafts, spindles, sleeves, pins, connecting rods, screws and nuts, intake valves, etc. ; After medium temperature quenching and tempering, it can be used to manufacture heavy-duty and wear-resistant parts. After quenching and tempering at low temperature, it is used to manufacture heavy-duty, low-impact and wear-resistant parts, such as worms, spindles, shafts and collars. After carbonitriding, it is used to manufacture large-size transmission parts with high impact toughness at low temperature, such as shafts and gears. 4.HT 150—— Application examples of gray cast iron: gear box, lathe bed, box, hydraulic cylinder, pump body, valve body, flywheel, cylinder head, pulley, bearing cover, etc. 5 —— 35—— Common materials for various standard parts and fasteners: appropriate strength, good plasticity, high cold plasticity and qualified weldability. Local upsetting and wire drawing can be carried out in cold state. Examples of applications with low hardenability after normalizing or quenching and tempering: suitable for manufacturing small-section parts, such as crankshafts, levers, connecting rods, shackles, etc. And various standard parts and fasteners 6, 65mn- examples of ordinary spring steel applications: small leaf springs, round springs, buffer springs, spring clockwork and spring rings, valve springs, clutch reeds and brake springs. 7.0cr18ni9-the most commonly used stainless steel (American steel grade 304, Japanese steel grade SUS304) features and uses: widely used as stainless heat-resistant steel, such as food equipment, general chemical equipment, raw energy industrial equipment 8, Cr12-commonly used cold-working die steel (American steel grade D3, Japanese steel grade). Because the carbon content of Cr 12 steel is as high as 2.3%, its impact toughness is poor, and it is easy to be brittle and fracture, and it is easy to form uneven * * crystal carbide. Cr 12 steel has good wear resistance, and is mostly used to manufacture punch and die of cold stamping die, punch, blanking die, cold upsetting die, cold extrusion die, drill sleeve, gauge, wire drawing die, stamping die, wire rolling plate, wire drawing die, powder metallurgy cold pressing die, etc. 9.DC53—— Features and application of commonly used cold working die steel imported from Japan: After high temperature tempering, it has high hardness, high toughness and good wire cutting performance. 9 10, SM45—— ordinary carbon plastic die steel (Japanese steel grade S45C) used for precision cold stamping die, drawing die, wire rolling die, cold stamping die and punch.
What are the main materials commonly used for shafts? Different materials and heat treatment specifications (such as quenching and tempering, normalizing, quenching, etc. ) Shaft parts should be selected according to different working conditions and use requirements to obtain certain strength, toughness and wear resistance.
45 steel is a common material for shaft parts. Better cutting performance, higher strength and toughness and other comprehensive mechanical properties can be obtained after tempering (or normalizing), and the surface hardness after quenching can reach 45~52HRC.
Alloy structural steels such as 40Cr are suitable for shaft parts with medium precision and high speed. After quenching and tempering, these steels have good comprehensive mechanical properties.
Bearing steel GCr 15 and spring steel 65Mn, after quenching and tempering and surface high-frequency quenching, the surface hardness can reach 50~58HRC, which has high fatigue resistance and good wear resistance, so high-precision shafts can be manufactured.
The spindle of precision machine tools (such as grinding wheel spindle of grinder and spindle of coordinate boring machine) can be made of 38CrMoAIA nitride steel. After quenching and tempering and surface nitriding, this steel can not only obtain higher surface hardness, but also maintain a soft core, so it has good impact toughness. Compared with carburized and quenched steel, it has the characteristics of small heat treatment deformation and high hardness.
Common electrical materials include transformers, control cabinets, loads, wires, switches and other components.
The core of common materials for molds should be forged, and the cavity should be made of 2738 material or 12 substrate (without heat treatment).
What are the common materials and heat treatment methods for gears? There are two common materials for gears:
One is carburized steel, which is mainly used to manufacture gears with low load but high requirements for wear resistance and impact resistance. The heat treatment method of this kind of steel is carburizing+quenching+low temperature tempering;
The other is quenched and tempered steel, which is mainly used to manufacture heavy-duty gears. The heat treatment method of this steel is quenching+high temperature tempering+surface quenching.
I can give you a bill of materials and covering scheme that I designed, and you will understand after reading it. Actually, it's very simple!
My QQ: 3050 17390
Commonly used materials for valves, you can download a JB/t5300 from the Internet, which specifies the preferred materials for general valves. Materials such as valve stem, valve body, nut and bolt. I hope it works for you.
Characteristics and applications of NAT? The full name of NAT in English is "Neork Address Translation", and in Chinese it means "network address translation". NAT is the IETF (Interengineering Task Force) standard, which allows the whole organization to appear on the Inter with a common IP(Inter Protocol) address. As the name implies, it is a technology to translate internal private network address (IP address) into legal network IP address. draw
Simply put, NAT is to use the internal address in the local area network. When the internal node wants to communicate with the external network, it will replace the internal address with the public address at the gateway (which can be understood as the exit, such as the door of the yard), so that it can be used normally on the external public network (inter). NAT can make multiple computers * * * enjoy interoperability, which solves the IP problem of public network * * well. In this way, you only need to apply for a legal IP address, and you can connect the computers in the whole LAN to the Internet. At this time, NAT shields the intranet, all intranet computers are invisible to the public network, and users of intranet computers are usually unaware of the existence of NAT. As shown in figure 2. The internal address mentioned here refers to the private IP address assigned to the node in the internal network. This address can only be used in the intranet and cannot be routed (a network technology that can realize different path forwarding). Although the internal address can be selected at random, the following addresses are usually used:10.0.0 ~10.255.255,172.16.0.0 ~172.00789.00000000805 Global address refers to a legal IP address, which is an address assigned by NIC (Network Information Center) or ISP (Internet Service Provider), representing one or more internal local addresses externally, and is a globally unified addressable address.
NAT functions are usually integrated in routers, firewalls, ISDN routers or separate NAT devices. For example, Cisco routers have added this function, and network administrators only need to set NAT function in the router's IOS to block the internal network. Another example is that the firewall maps the internal address 192. 168. 1 to the external address 202.96.23. 1 and external access 202.96.23. 165438. In addition, for small enterprises with limited funds, this function can now be realized through software. Windows 98 SE and Windows 2000 both include this feature.
NAT technology type
There are three types of NAT: static NAT, dynamic address NAT and network address port translation NAPT.
Among them, static NAT is the simplest and easiest to set, and each host in the intranet is permanently mapped to a legal address in the external network. Dynamic address NAT defines a series of legal addresses in the external network and maps them to the internal network through dynamic allocation. NAPT maps internal addresses to different ports of external network IP addresses. According to different requirements, the three NAT schemes have their own advantages and disadvantages.
Dynamic address NAT only translates IP addresses. It assigns a temporary external IP address to each internal IP address, which is mainly used for dialing. Dynamic NAT can also be used for frequent remote connections. When the remote user connects, the dynamic address NAT will assign him an IP address, and when the user disconnects, this IP address will be released for future use.
Napt (Network Address Port Translation) is a common translation method. NAPT is widely used in access devices, which can hide small and medium-sized networks behind legitimate IP addresses. Unlike dynamic address NAT, NAPT maps internal connections to a single IP address in the external network and adds the TCP port number selected by the NAT device to this address.
When using NAPT in Inter Milan, all the different information flows seem to come from the same IP address. This advantage is very practical in a small office. By applying for an IP address from an ISP, you can connect multiple connections to Inter through NAPT. In fact, many SOHO remote access devices support dynamic IP addresses based on PPP. In this way, ISP can use an external IP address to correlate with multiple internal IP addresses, and even does not support NAPT. Although this will lead to certain congestion in the channel, it is worthwhile to use NAPT considering the saving of internet access fees and easy management of ISP.
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With the rapid development of Internet, the shortage of IP address has become a very prominent problem. In order to solve this problem, a variety of solutions have emerged. Here is a brief introduction to an effective method in the current network environment, namely the address translation (NAT) function.
I. Introduction to NAT
The function of NAT (Network Address Translation) refers to the IP address that can be customized at will without application in a network. In a network, computers communicate with each other through internal IP addresses. When an internal computer wants to communicate with the external Internet, a device with NAT function (such as a router) is responsible for converting its internal IP address into a legal IP address (that is, the applied IP address) for communication.
Second, the application environment of NAT:
Situation 1: An enterprise doesn't want external network users to know its internal network structure, but it can isolate the internal network from the external network through NAT, so the external network users simply don't know the internal IP address set through NAT.
Case 2: There are few legitimate IP addresses applied by an enterprise, but there are many internal network users. Through NAT function, multiple users can communicate with external Inter by sharing a legal IP at the same time.
Third, set the hardware configuration and software configuration of the router required by NAT:
A router with NAT function must have at least one internal port and one external port. Network users connected through internal ports use internal IP addresses.
The internal port can be any router port. The external port is connected to an external network, such as Inter. An external port can be any port on the router.
IOS of routers with NAT function should support NAT function (the router used in this example is Cisco250 1, and its IOS is 1 1.2 or above).
Four, some concepts about NAT:
Internal local address: the internal IP address assigned to the computer in the internal network.
Internal global address: a legal IP address that represents one or more internal local addresses when entering IP communication. Need to apply for the IP address.
How to set the verb (abbreviation of verb) NAT:
NAT settings can be divided into static address translation, dynamic address translation and multiplexing dynamic address translation.
1, static address translation environment
Static address translation converts internal local addresses into internal legal addresses one-to-one, and needs to specify which legal address to translate. If the internal network has services that can be provided to external users, such as e-mail servers or FTP servers, the IP addresses of these servers must adopt static address translation so that external users can use these services.
Basic configuration steps of static address translation:
(1). Establish static address translation between internal local address and internal legal address. In the global setting state, enter:
Ip nat internal source static internal local address internal legal address
(2) Specify the internal port connected to the network, and enter:
Internal ip nat
(3) Specify an external port connected to an external network, and enter:
External ip nat
Note: Multiple internal ports and multiple external ports can be defined according to actual needs.
2. Applicable environment for dynamic address translation:
Dynamic address translation is also a one-to-one conversion between local address and internal legal address, but dynamic address translation is to dynamically select an unused address from the internal legal address pool to convert internal local address.
Basic configuration steps of dynamic address translation:
(1), in the global setting mode, define the internal legal address pool.
Ip nat address pool address pool name start Ip address end IP address subnet mask
Where the address pool name can be set arbitrarily.
(2) In the global setting mode, define a standard AES-list rule to allow which internal addresses can be dynamically translated.
Aess- list labels allow source address wildcards.
Where the reference number is an integer between 1-99.
(3) In the global setting mode, the internal local address specified by aess-list is converted with the specified internal legal address pool.
Ip nat Internal Source List Access List Label Pool Internal Legal Address Pool Name
(4) Specify the internal port connected to the internal network in the port setting state:
Internal ip nat
(5), specify the external port connected to the external network.
External Ip nat
3. Applicable environment for multiplexing dynamic address translation:
Multi-path dynamic address translation is a dynamic address translation at first, but it can allow multiple internal local addresses to use one internal legal address. This conversion is extremely useful when only a small number of IP addresses are applied, but at the same time there are often more users than legal addresses on the external network.
Note: When multiple users use an IP address at the same time, the external network uniquely identifies a computer through the router using upper-layer port numbers such as TCP or UDP.
Configuration steps of multiplexing dynamic address translation:
In global setting mode, define the internal address pool.
Ip nat address pool address pool name start Ip address end IP address subnet mask
Where the address pool name can be set arbitrarily.
In the global setting mode, a standard aess-list rule is defined to allow which internal local addresses are dynamically translated.
Aess- list labels allow source address wildcards.
Where the reference number is an integer between 1-99.
In the global setting mode, the setting establishes multi-path dynamic address translation between the internal local address and the internal legal IP address.
Ip nat Internal Source List Access List Label Pool Internal Legal Address Pool Name Overloaded
In the port setting state, specify the internal port connected to the internal network.
Internal ip nat
In the port setting state, specify an external port connected to an external network.
External ip nat