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August 10, 2022 at 4:00 am in reply to: What are the advantages of dimensional inspection in casting? #2118
The dimensional inspection verifies that a casting component complies with any dimensions specifications or tolerances. This inspection can be carried out manually or with the aid of a coordinate measuring machine (CMM), which takes exact measurements using probes. The most accurate method of measuring the products is with a CMM.August 10, 2022 at 3:59 am in reply to: What is the role of Container Loading Supervision in Quality Inpsection? #2117
A Container Loading Supervision in China and Asia will make sure the right products are loaded and packaged effectively, and that things are not damaged, as your goods will travel for days or weeks to reach their destination.
AQL in Actual Use
Acceptable quality level (AQL): Generally speaking, AQL refers to the lowest quality level that is nevertheless regarded as acceptable. It is the highest possible percentage of defects that can be deemed acceptable. Accepting an AQL lot should be highly likely. A 0.95 probability corresponds to a 0.05 risk.
Rejectable quality level (RQL): Also known as lot tolerance percent faulty, this term denotes an inadequate quality level (LTPD). Some tables have standardized the consumer’s risk to be 0.1. Accepting an RQL lot has a low likelihood.
Quality level of indifference (IQL): This level of quality lies in between AQL and RQL. Each defect type is interpreted differently by various companies. But buyers and sellers settle on an AQL criteria that is suitable for the amount of risk that each side takes. During a pre-shipment inspection, these standards are utilized as a guide.
WILL THIRD PARTY INSPECTIONS BENEFIT MY COMPANY?
Third-party inspections are generally regarded as a well-justified expense by most businesses. They are carried out by organizations with extensive experience who work on the ground every day. They give an unbiased assessment on the quality of the goods and allow you to keep an eye on quality consistency on site without having to be present.
The purchasers will be fully aware of the manufacturing process, even if they are far away, and will be able to create a trusting connection with the supplier. Furthermore, despite their cost, TPIs end up saving you money by preventing costly errors or eliminating the need for an in-house QC staff.
IN CERTAIN CIRCUMSTANCES, A THIRD PARTY INSPECTION IS ESSENTIAL.
collaborating with new vendors
Detecting quality issues in a timely manner
Repeated product quality difficulties (but we’d rather not get to this conclusion and examine the goods for all shipments, at various stages of the manufacturing process – it’ll be less expensive than having to deal with quality issues with the supplier on goods that have already been sold)
Purchasing high-end gadgets, industrial equipment, and other high-end things.
Today, high-speed machining is commonplace in many machine shops all over the world. It has become the norm rather than the exception in industries like moldmaking and aircraft. The achievement of improved efficiency and productivity through increasingly higher spindle speeds is one clear benefit of this trend. However, because centrifugal force grows with the square of the speed, the potential for deleterious consequences on the machine and the workpiece due to vibration increases exponentially as the spindle speeds of machining centers increase. Unbalance is one of the most common causes of vibration and one of the easiest to control. Because all machining centers’ spindles are equally balanced to the necessary ISO suggested levels, the toolholder, as well as the tool itself, is the main source of unbalance.
Why is it important to maintain a sense of equilibrium?
Unbalanced vibration has a number of well-known consequences on the machining process. Chatter is the most evident. Reduced spindle speed is a common response to chatter, which, of course, limits the machining center’s capabilities. The main consequence on the workpiece is a poor surface finish and the inability to maintain tight tolerances. And, on the machine, you’ll see a significant reduction in tool life, as well as the likelihood of spindle and bearing failure over time. This is why many machining center manufacturers encourage balanced tooling, and in some situations, if balanced toolholders are not used above a particular speed, the spindle guarantee may be worthless. Historically, 8,000 to 10,000 rpm has been used to define high-speed machining for the sake of balance. There are, however, a variety of factors that influence this. The spindle speeds at which toolholder balancing becomes crucial are discussed in greater depth in this article.April 17, 2022 at 1:49 pm in reply to: Importance of Social Compliance Audit in Quality Inspection #1632
A social compliance audit, often known as a social audit or ethical audit, looks at more than simply what your supply chain produces. Whereas a production line inspection may focus on the quality of your products, a social compliance audit extends beyond that to check a factory’s working standards. The corporation must demonstrate that it conducts business in accordance with particular social and ethical obligations, as well as local legislation. An audit examines all of these factors and more to provide you peace of mind about your supply chain. Social compliance audits are optional, and they can be conducted at the client’s convenience by a third-party quality assurance business.
What is the difference between a compliance audit and a regular audit?
A compliance audit is carried out to ensure that a company follows particular rules and regulations set forth by local legislation or a specific agreement. Governments and authorities would normally conduct them. Depending on the industry in which the company operates, a compliance audit may involve employment law, workplace conditions, taxes, or a variety of other issues. A compliance audit can be conducted by a variety of different parties, depending on the circumstances and arrangements, while the sector will dictate who does the audit.
One thing is certain: it will be carried out by a third party to verify that the results are fair and accurate. A compliance audit may be performed or commissioned for a variety of reasons. For example, a corporation may have broken certain rules in the past and will need to be examined to ensure that they have resolved their issues and are in compliance with their present operations.
What is the significance of social compliance?
In the year 2020, it will be critical for businesses and organizations to be ethical, fair to their employees and clients, and conscious of their surroundings. Sustainability is critical for any organization, and demonstrating good waste, pollution, and environmental procedures should be standard procedure.
What Is the Difference Between a CNC VMC and a CNC HMC?
1. Differences in Structure Choosing between VMC and HMC is a difficult task.
The Z-axis structure is the major distinction between the VMC and the HMC. The fundamental difference between both is that the VMC’s Z-axis goes vertically downward to complete the processing, whereas the HMC’s Z-axis moves horizontally downward to complete the processing.
2. Workbench Variation Choosing between HMC and VMC is a difficult task.
The VMC’s worktable is commonly a T-slot worktable with a cross slide arrangement. The vertical movement of each other is controlled by two sets of motion motors. The Y-feeding guide rail covers the X-feeding worktable. The HMC’s worktable can only move in one of two directions: X or Y. The worktable is usually a rotary worktable with a dot matrix screw hole table, and choosing an interchangeable double worktable is quite simple.
3. CNC VMC and HMC Machines Process Various Parts
The vertical machining center can handle disk, sleeve, and plate components. It usually has three linear motion coordinate axes, and to process spiral parts, a rotary table that spins along the horizontal axis can be mounted on the worktable.
The horizontal machining center may process components with more than two sides, as well as parts with holes and surfaces oriented radially around them, such as box and shell parts; if the position accuracy of the processed parts is critical, a high-precision horizontal machining center should be used.
CNC controller is the electromechanical bits that connect the computer to the machine.
Types of CNC Controllers
Industrial OEM CNC Controllers
Industrial OEM CNC Controllers are the ones used on Industrial CNC Machines like Haas. They’re the very hind end of the market.
These are not very common for DIY projects due to their expense. Not only is the controller itself expensive and fairly hard to come by (though one does see them from time to time on eBay), but Industrial OEM Controllers expect premium sub-components too. Industrial Quality Servo Drives, Home / Limit Switches, and all the rest really run up a hefty price tag in a hurry.
While these controls are expensive, lately I’ve seen controls such as the low-end of the Siemens line coming down in price in places like eBay. It looks like they’re testing the low-end market. If they keep coming down, these controls may make more sense on a DIY CNC Project than it seems.
I’m not going to talk further about these controls as they’re a pretty advanced topic. You might find the article I did that analyzes what features Hobby CNC Controllers are missing compared to industrial controls intersesting.
CNC Retrofit Controllers
Just a small step down from Industrial OEM Controllers are CNC Retrofit Controllers like Centroid.
These controllers are marketed for converting manual machines to CNC, for example, a Bridgeport manual milling machine. They’re also sold as a way to update obsolete controls on industrial CNC Machines to bring the more up-to-date features and performance.
They’re still not cheap, but they’re starting to fall into the range of what a DIY CNC’er might afford.
PC Based CNC Controllers
There are three main players in this market:
Mach 3 & Mach 4
All three have good reputations with varying trade-offs of features, functionality, price, and ease of use.
5 common CNC machining materials
Since any material — metal or plastic — that’s hard enough for machining can be used for CNC manufacturing, product teams are spoiled for choice. This short list provides a quick gloss of some of the most common materials used in CNC manufacturing today.
Aluminum alloys are easy to machine in large volumes, have a good strength-to-weight ratio, and high thermal and electrical conductivity. They are also naturally resistant to corrosion. Aluminum 6061 is an all-purpose aluminum alloy often used for CNC machining. It is typically found in automotive parts, bike parts, sporting goods, and other recreational items. This material is highly machinable; however, it can be pricier than other metals and doesn’t hold up well in the presence of saltwater or certain chemicals. Aluminum 7075 is a step up from 6061. Ideal for aerospace frames and high-performance recreational equipment, it’s the strongest commercially available aluminum alloy.
2. STAINLESS STEEL
Stainless steel alloys are strong and resistant to distortion, wear, and corrosion. 303 stainless steel includes sulfur for improved machinability, but this material has a number of limitations that engineers must keep in mind.
303 cannot be cold-formed, heat-treated, or welded, and special care must be taken with speed/feeds and the sharpness of cutting tools during CNC manufacturing. That said, 303 makes excellent nuts, bolts, non-marine grade fittings, shafts, and gears.
304 stainless steel is a non-magnetic, all-purpose steel for CNC machining known for its toughness. It’s readily machinable and corrosion-resistant like 303, but it can be welded. 304 is well-suited for a wide range of consumer and industrial applications, kitchen accessories, tanks and pipes, architecture, and more. 316 stainless steel is even more corrosion-resistant than 304 or 303 thanks to the addition of molybdenum. It’s strong, weldable, and one of the few marine grade stainless steels.
Since it’s impossible to tell stainless steels apart by sight alone, engineers should make sure to test the raw material to confirm the characteristics of the steel they’re using.
3. CARBON STEEL
Carbon steel 1045 is a mild grade of carbon steel. Manufacturers often machine with this material because it is less expensive than most stainless steels but stronger and tougher. 1045 is easy to machine, weldable, and can be hardened or heat-treated to achieve various hardnesses.
This material is ideal for nuts, bolts, gears, shafts, connecting rods, and other strong, small mechanical parts. 1045 can also be used for architectural applications, but it must be surface-treated to prevent rust and corrosion.
Known for its high strength, toughness, and corrosion resistance, titanium is often employed to manufacture parts for the most demanding aerospace, military, and industrial applications. This material is also biocompatible and suitable for use in medical device manufacturing.
However, titanium is more expensive than any other metal in its commercial form, doesn’t polish well, and is a poor conductor of electricity. Engineers should also be aware that titanium is challenging to machine, and requires special cutters.
Nylon is an all-purpose, low-friction thermoplastic that is often used as an alternative to metal in CNC-manufactured parts. This material is stiff, strong, impact-resistant, chemical-resistant, but surprisingly elastic. Nylon responds well to additives and fillers, so engineers can feel free to manipulate this material to achieve their desired properties.
Popular applications for nylon include electrical molding, fuel system components, gears, food packaging, fabric, and more. However, nylon absorbs moisture easily, which may negatively impact the dimensional stability of a part.
MOST COMMON MATERIALS USED IN CNC MACHINING:
Low Carbon Steel
At present, DNC system includes not only the NC program, but also the manufacturing data of the specific tasks required for the production, such as cutting tools data, scheduling, configuration information of machine tools, and so on, and part of the DNC system also has the functions of machine tool state acquisition and remote control.