false rotary table c plate made in china

Drilling involves pipe handling operations in a wellbore, and this in turn requires a false rotary table, a vital cog in the overall success of the operations. At ShalePumps, the need for constant improvement has resulted in an extensive range of precision engineered equipment, of which the false rotary table occupies the limelight.

This hydraulically driven false rotary table is guaranteed to seamlessly engage the tubulars in the wellbore. Pivotal to drilling operations are the sequence of engaging and lowering tubulars into the wellbore. The false rotary table manufactured at our facility is a fine example of harmony between design, materials and precision engineering.

Featuring a mighty load capacity of 1.3 million pounds operating at a maximum speed of 20 rpm, the false rotary table assists the drilling operations in continuous long drawn operations. Pipe handling requires the seamless and sturdy operation of the false rotary table.

ShalePumps, backed by substantive body of experience and knowhow has developed this high performance false rotary table to ably support drilling operations by incorporating a blend of advanced materials and precision engineering. With a guaranteed long life and trouble free run, the ShalePumps false rotary table spins other models out of reckoning.

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I spent a lot of time aligning my RT to the spindle. I got it within a thou or so. That was the best I could do. Then, I added a fixture plate to the top of it and aligned that as well. So, I assume means the two are aligned to each other?

What are some of the best Rotary table brands you can buy? I only buy tools once so quality of the most important thing. I’ll happily buy vintage if people truly think they are better. I have a Bridgeport (pictured below)

Almost zero experience with a mill but I thought perhaps it will be easier to do this cut on the mill than using my router. Besides, if this cut is successful then I can do the required reaming cuts on the inside of this wheel which has a few more smaller circles.

Here"s a mystery for all you hobby milling machine enthusiasts. Help me ID this rotary table. I"m considering purchasing it, but can"t figure out who made it.

Finally complete. The casting came out very nice, little if any hydrogen bubbles or oxide inclusions. 11" diameter x 1" thick, 6 T slots, referencing rings 1/2" apart. See if I can get a photo to post.

So, here"s what I"m wondering. About half the time I use the rotary table I find the hand wheel interferes with where I"d like to clamp it down. Looking at other tables this seems to be the common configuration, where the handwheel interferes with the mounting plane(s) of the table. Why would...

not getting any feedback to a previous post I gotta wonder if there isn"t something wrong with an Advance Rotary Table. I see lots of posts regarding "what to buy" and "I settled for a Chinese knockoff". Just wondering what is the problem? This seems to be an extremely well built and accurate...

I have a vertex 10" Rotary table with mounted chuck, I use it often. There are quite a few occasions I wish it was motorized. Has anyone done a DIY motor on their rotary table and not spent a fortune ? I"ve seen pretty expensive motors so i"m looking for DIY options. I think I may have even...

I have barely enough room left to get tooling in. Had to use a short 3" boring bar. I can see another 2 inches of shiny ways below where the knee is stopped by the limit switch.

I"ve become a (happy) owner of a new-to-me 8" Phase II horizontal rotary table. Unfortunately it came with the dividing plate setup and no handwheel, so I need to make one. If you have this model of the table, I would really appreciate if you could post a picture and/or dimensions of...

So I need a rotary table for a couple of projects I have in mind, making round things on my Jet 15 mill/drill. I don"t have a lathe. I"m thinking 6" would be a reasonable size both for the things I need to make and the size of my mill. I see cheap imports on ebay starting around $160, Phase...

Having purchased a 6" rotary table from Chronos, I hope I am permitted to say this. The Chronos table was very poorly finished and the engraving was barely visible through the corrosion. I think this was a returned item.. The cranking handle was fixed on its spindle. It went back. Purchased a 6" one from Warco and what a difference. Beautifully finished smooth as silk good legible engraving and finish with a fully rotating handle. Backlash adjusted to virtually nil. Good job Warco!

The RT itself, was OK, just that there were errors in the chart supplied with the Division Plates. The first of which was found the hard way after thinking that i could not count. Of course it had to be in the number of Divisions that I wanted to produce!

Having made up a spreadsheet, I found that there were eight errors or omissions in the chart. Probably the result of misreading hand written figures.

I did not need the Vertex as for my needs was a bit over kill. The one from Warco looks so close to a Vertex that I doubt there would be much advantage to spend some £100 more. I am happy now. The price difference was between the Chronos and Warco one, making the Warco a bargain

With a lot of internationally sourced items, lathes, drilling machines and accessories etc., I get the impression that there are some big factories somewhere each exclusively producing one item which are then sprayed different colours and branded with different names but are essentially identical. Drilling machines especially all seem to be of the same design and specification whatever the colour or brand may be. I may be quite wrong but the similarities of most of the items on the market are easy to recognise. I have also noticed this with cheap DIY power tools which all mostly seem to perform just as well as a "branded" item. I have found this with the Clarke brand as marketed by Machine Mart, especially their "contractor" series, which have served my purposes well enough although I know some will disagree on this point.

With a lot of internationally sourced items, lathes, drilling machines and accessories etc., I get the impression that there are some big factories somewhere each exclusively producing one item which are then sprayed different colours and branded with different names but are essentially identical. Drilling machines especially all seem to be of the same design and specification whatever the colour or brand may be. I may be quite wrong but the similarities of most of the items on the market are easy to recognise. I have also noticed this with cheap DIY power tools which all mostly seem to perform just as well as a "branded" item. I have found this with the Clarke brand as marketed by Machine Mart, especially their "contractor" series, which have served my purposes well enough although I know some will disagree on this point.

Yep. Some look similar but in different paint, but some may look identical on the outside but be completely different (quality-wise) under the surface. Hardening parts and machining hardened parts very quickly adds expense. Out-of-tolerance parts can be used for the bottom end rubbish.

I too purchased a Warco HV6 rotary table with dividing plates etc. As with most Chinese imports it needed a strip down and clean. Apart from the a small adjustment with one of the clamping plates it has served me well. The only annoying aspect are the tee slots not in the vertical and horizontal position when the table was set to 0 degrees.

I am interested in all the comments and respect everybody"s point of view but I look at it this way. Production of any component these days is mainly done on CNC machines as far as I am aware. Gone are the days when armies of semi-skilled men in blue overalls stood behind semi-automatic capstan lathes turning out parts that would be as good as the tool-setter"s level of skill and where variations in accuracy might creep in. Although I don"t work in the manufacturing engineering industry, or work at all for that matter these days, it is my understanding that everything is now designed on a computer (gone also is the traditional drawing office) and the production programs are sent directly to CNC machines which, I am told, even compensate for their own tool wear. Therefore, it seems to me that it no longer matters where the product is designed, although quality of design must play a part, or where the CNC machine is located because it will run the same program to exactly the same level of accuracy and produce exactly the same components. Production will only follow where the necessary skills and energy costs are the lowest. I would agree that the quality of the materials used may have an impact on the finished product but overall wherever the production takes place it will all be pretty much of a muchness. Hence, the availability of reasonable and cheap DIY power tools and the similarity of machine tools only differentiated by colour and brand. Am I incorrect in thinking this way?

There is no doubt about the quality of the Warco HV6 rotary table. It was from a newly delivered batch and does not need dismantling to clean etc. The design is quite different from what was supposed to be a Soba brand from Chronos. which did not have a Soba marking. The Warco was superior in all respects and looks almost exactly like a Vertex even down to the black crackle finish. I rest my case. I did note that the Vertex had just three slots as opposed to four on the Warco.

CNC will produce consistent levels of accuracy, but the finished product quality is determined by the Design, the Materials used, the of component cleamliness and ultimately, the care taken in assembly.

Not every factory has quality modern machine tools, some of those far eastern factories rely on old worn out poorly maintained second hand machines, the quality of the products are reflected in this. Also some of the components are probably produced in back street workshops, like every product in this modern world the big factories sub a lot smaller parts to little producers.

Therefore, it seems to me that it no longer matters where the product is designed, although quality of design must play a part, or where the CNC machine is located because it will run the same program to exactly the same level of accuracy and produce exactly the same components. Production will only follow where the necessary skills and energy costs are the lowest. I would agree that the quality of the materials used may have an impact on the finished product but overall wherever the production takes place it will all be pretty much of a muchness. Hence, the availability of reasonable and cheap DIY power tools and the similarity of machine tools only differentiated by colour and brand. Am I incorrect in thinking this way?

Broadly yes. And new ways are deadly to traditional and old-fashioned production methods. The chap who thinks he can work in Whitworth at a manual lathe is doomed. In manufacturing you have to keep up: it"s vicious.

However, modernising production isn"t complete yet. Around the world there are plenty of businesses who are behind the curve. It"s still possible to find excessively cheap stuff being made by low-productivity methods. A small foundry with low labour costs and a few basic machine tools might be scratching out a living by knocking out HV6 clones. Goods made this way can vary enormously from excellent to junk, even from the same factory. But these guys are batting on a sticky wicket. An up-to-date factory that wants the business can produce the same item better and at lower cost. It may not be worth their while.

Model Engineers are at a disadvantage because the market is small and their isn"t much competition driving improvement. In comparison, almost every home wants a DIY electric drill, so there"s high demand for reasonable kit. Better but affordable electric drills are profitable because they sell by the million. DIY tools are excellent value because the rubbish has mostly been forced out.

Home workshop gear sells in much smaller quantities, and the problem is compounded by Model Engineer"s being notoriously tight. If we all tripled our spending, I"m sure hobby makers would offer better kit. Doubt it will happen though; I can only think of one hobbyist coughing up serious money for a new industrial grade machine, and there"s a lot of dodgy cheapo stuff bought off the web by optimists!

I"m surprised at how good hobby tools are for the money. Had a few lemons, but generally my mid-range purchases have done what"s needed of them. I think it"s because much of it is made economically by modern methods, not by rice-farmers in a shed!

As with most things the design is to a budget so what get sent to the CNC is determined by the design, higher tolerance will take longer and cost more so the cheaper item may not have such high tolerances. Could also be decided at the design stage that a machined finish will get it within budget rather than the better ground finish. Then there are material choices and any treatment to those materials.

As mentioned above a lot of old first generation CNC machines may have been exported and these may be what is being used to build the lower budget products. Top of the range CNC gets used when the customer is willing to pay the top range price for their rotary table that is why some 6" ones cost a couple of thousand pounds compared to £150-200 for the run of the mill hobby ones.

Some informative replies to the points I raised, so thanks to you all for adding to my education. But just before I let this thread go, please let me say that I bought a 6" British made Sharp rotary table from Mill Hill Supplies many years ago. It has never been used because shortly afterwards I acquired what immediately looked to be a far superior Vertex model for a very reasonable price at an exhibition trader"s stand and this was at a time when the air was full of derogatory comments about the far-eastern products which were coming on to the market. I assumed even then that this was because the much higher quality "Chinese" product had been made using modern production methods designed to supply the world market whilst at the time I think a lot of people would have said that British made Sharp was better because it had been made using traditional skills by a small engineering company in the north of England. I apologise if this comment disappoints those who still cling the rose-tinted view that British was best.

CC, the bottom line is the far eastern stuff is made to a price point not a quality point so it varies like hell & a CNC machine can produce just as many bad parts as a manual one but it will do it a lot quicker. I"m also pretty sure quality control is absent in a good many Chines/Indian factories.

Diversified offers a wide range of Manual Elevators such as Side Door Elevators, Single Joint Elevators, Slip Type Elevators, Safety Clamps and Rotary Slips for 2-3/8” diameter tubing to 30” diameter casing.

Side Door Elevators:Used for handling collar type casing, all of our Side Door Elevators are equipment with a safety latch lock. Our Side Door Elevators come in SLX 150-250 Ton variants from 4-1/2” to 30” OD.

Single Joint Elevators:The SJX Single Joint Elevator is designed for running single joints of tubing and casing from V-door to well center. Our inventory of SJX Single Joint Elevators range from 2-3/8” up to 30”. All comes with load tested Slings and Swivels.

Slip Type Elevators:Our Slip Type Elevators comes in HYC 200 Ton, YT 150 Ton and YC 75 Ton variants. With Slip and Inserts to accommodate 7” Casing down to 2-3/8” Tubing. We can also provide Low Penetrating Dies for Chrome running and handling applications upon request.

Safety Clamps:Used to secure flush tubular products during installation. Our inventory of MP series and Type “C” and “T” Safety Clamps are available from 2-3/8” to 30” OD. We can also provide Low Penetrating Dies for Chrome running and handling applications upon request.

Rotary Slips:Our inventory of Rotary Slips includes SDS, SDML, SDXL and CMS-XL variants from 2-3/8” to 30” OD. We can also provide Low Penetrating Dies for Chrome running and handling applications upon request.

Diversified also offers the following equipment to complete your Casing and Tubing Running Needs: Thread Protectors, Stabbing Guides, Drifts, Bowl & Slips, C-Plate)

Thread Protectors: We offer Air Operated or Clamp-on Type Thread Protectors to offer safe, reliable casing and tubing pin-end protection from 20” casing down to 2-3/8” tubing.

Stabbing Guides:Stabbing Guides are engineered to consistently align and safely guide two sections of pipe together through the use of specially formed polyurethane shells, thereby greatly reducing the chance of pin or box damage. We offer stabbing guides from 13-3/8” casing down to 2-3/8 tubing”.

Jigs and fixtures are manufacturing tools that are used to produce identical and interchangeable components. These workholding and tool guiding devices are designed for use in the machining and assembly of parts.

To get the greatest benefit from jigs and fixtures, a basic understanding of their construction is necessary. Jigs and fixtures are identified one of two ways: either by the machine with which they are identified or by their basic construction. A jig, for instance, may be referred to as a “drill jig.” But if it is made from a flat plate, it may also be called a “plate jig.” Likewise, a mill fixture made from an angle plate may also be called an “angle-plate fixture.” The best place to begin a discussion of jig and fixture construction is with the base element of all workholders, the tool body.

In manufacturing operations, it"s important to meet the higher demands of customers. This means producing quality products as fast and efficiently as possible. Jigs and fixtures help make manufacturing processes more efficient and precise.

While jigs and fixtures work together, these are two distinct tools used in mass production processes. The two terms are often used incorrectly as synonyms but serve different purposes.

A jig controls and guides the cutting tool to work at a predefined location on a workpiece. Fixtures are used for supporting and locating a workpiece. Fixtures do not guide the tool on a workpiece like a jig.

Jigs are typically lighter than fixtures, which need additional force to stand up to cutting force and vibration. While fixtures require clamping and accessories, a jig can be held or fixed to a table depending on the application.

This section serves as a comprehensive guide to understanding the design of jigs and fixtures, and how each of these critical work holding devices operates in practice. Carr Lane Mfg. Co. has been a market leader in jig and fixture components for 70 years. Learn more about the various types of jigs and fixtures developed by Carr Lane Mfg. Co.

The tool body provides the mounting area for all the locators, clamps, supports, and other devices that position and hold the workpiece. The specific design and construction of a tool body are normally determined by the workpiece, the operations to be performed, and the production volume. Economy is also a key element in good design.

The three general categories of tool bodies are cast, welded, and built up, Figure 4-1. Each type of construction can be used for any workpiece, but one is often a better choice than the others. The first step toward an economic design is to know and weigh the strengths and weaknesses of each.

Cast tool bodies are made in a variety of styles and types. The most common casting materials for tool bodies include cast iron, cast aluminum, and cast magnesium. Cast materials occasionally found in specialized elements for tool bodies, rather than in complete tool bodies, are low-melting-point alloys and epoxy resins.

Cast tool bodies can have complex and detailed shapes. Such shapes require fewer secondary machining operations. Cast materials dampen vibration. They are most often found in relatively permanent workholders; workholders not subject to drastic changes. Cast tool bodies have three major drawbacks: (1) they are not easily modified for part changes; (2) their fabrication cost is high; (3) they require a lengthy lead time between design and finished tool body.

Welded tool bodies are also made from a wide variety of materials. The most common welded tool bodies are made of steel or aluminum. Welded tool bodies are inexpensive to build and they are usually easy to modify.

Heat distortion is the major problem with welded tool bodies. For best results, and to ensure stability of the tool body, welded tool bodies should be stress relieved before final machining and use. Be aware, however, this will add to the preparation lead time and cost, as well. Another problem with welded tool bodies is in the use of dissimilar materials. When a steel block, for example, is added to an aluminum tool body, it should usually be attached with threaded fasteners rather than by welding to the body.

Built up tool bodies are the most common tool body today. These tool bodies are very easy to build, and usually require the least amount of lead time between design and finished tool. The built up tool body is also easy to modify for changes in the part design. Like the welded body, built up tools are durable and rigid, and have a good strength-to-weight ratio. Depending on the complexity of the design, the built up tool body may be the least expensive to construct.

Built up tool bodies are usually made of individual elements, assembled with screws and dowel pins. The built up tool body is often used for precision machining operations, inspection tools, and some assembly tooling.

Preformed materials can often reduce the cost of machining tool bodies. These preformed materials include precision tooling plates, tooling blocks, risers, cast sections, and angle brackets. Other materials include ground flat stock, drill rod, or drill blanks, and also structural sections such as steel angles, channels, or beam.

Tooling plates are standard, commercially available base elements used to construct a variety of different workholders. Like other fixturing elements, these plates come in several variations to meet most fixturing requirements.

Rectangular Tooling Plates: Of all standard tooling plates, the rectangular ones, Figure 4-2, are the most popular. Their rectangular form works well for a wide variety of workholders. The plates come in a wide range of sizes, from 12” x 16” to 24” x 32”. Rectangular tooling plates are made of ASTM Class 40 gray cast iron, machined flat and parallel.

Another tooling-plate variation is the round tooling plate, Figure 4-3. Round tooling plates work well on rotary or indexing tables. These tooling plates are available in 400mm, 500mm, and 600mm diameters. They are made of ASTM Class 40 gray cast iron, and have a series of mounting holes.

The square shape is ideal for palletized arrangements where a square tooling base is necessary. Square tooling plates come in five sizes to fit standard machining-center pallets 320mm, 400mm, 500mm, 630mm, and 800mm square. Plates are made of ASTM Class 40 gray cast iron.

Similar to square pallet tooling plates, except made for rectangular machining-center pallets 320 x 400mm, 400 x 500mm, 500 x 630mm, and 630 x 800mm. Figure 4-5 shows this type, and how it can also be mounted on a square pallet by adding a spacer.

Figure 4-5.Rectangular pallet tooling plates are for machining centers with rectangular pallets, or square pallets requiring a larger mounting surface.

The angle tooling plates, Figure 4-7, are another useful tooling plate. These vertical plates allow mounting a large part approximately on the pallet’s center-line. These plates are made to fit machining-center pallets 400mm, 500mm, 630mm, and 800mm square. Angle tooling plates are made from ASTM Class 45 cast iron.

Platform Tooling Plates. Platform tooling plates are a variation of the square tooling plate. These plates are specifically designed for a mounting surface that must be elevated off the machine-tool table. As shown in Figure 4-6, the raised mounting surface permits easier access to the workpiece with horizontal machining centers. The added height provides the necessary clearance for the machine-tool spindle. The design also eliminates the dead space between the machine-tool table and the minimum operating height of the spindle.

Added height is also beneficial when machining short parts on a vertical machining center to avoid Z-axis limit errors. Platform tooling plates come in three sizes for 500mm, 630mm, and 800mm pallets. Platform tooling plates are made of ASTM Class 45 cast iron.

The angle tooling plates, Figure 4-7, are another useful tooling plate. These vertical plates allow mounting a large part approximately on the pallet’s centerline. These plates are made to fit machining-center pallets 400mm, 500mm, 630mm, and 800mm square. Angle tooling plates are made from ASTM Class 45 cast iron.

Tooling blocks are often used on horizontal machining centers. The most-common tooling blocks are the two-sided and four-sided styles. These blocks work both for mounting workpieces directly, or for mounting other workholders. All working faces are accurately finish mac hined to tight tolerances, and qualified to the base.

Dual mounting capability, Figure 4-8, allows both JIS mounting (locating from two reference edges) and DINmounting (locating from center and radial holes).

The two-sided tooling block, Figure 4-9, is for mounting workpieces or workholders on two opposite sides. Two-sided tooling blocks work well for fixturing two large workpieces.

The four-sided tooling block, Figure 4-10, mounts workpieces or workholders on four identical sides. Four-sided tooling blocks, with their four working surfaces, are typically chosen to maximize production. These tooling blocks are available in five different pallet sizes: 320mm, 400mm, 500mm, 630mm, and 800mm.

Precision cast sections come in a variety of shapes and sizes. Most cast sections are available in standard lengths of 25.00”, and all sizes and styles are available in precut 6” lengths, with squareness and parallelism within .005”/foot on all working surfaces. The sections can also be ordered cut to any specified length. The two common cast-section materials are cast iron and cast aluminum. The cast iron sections are made of ASTM

Class 40 cast iron with a tensile strength of 40,000 to 45,000 psi. The aluminum sections are 319 aluminum with a tensile strength of 30,000 psi. Cast elements are used mainly for major structural elements of jigs and fixtures rather than as accessory items. Depending on the workholder design, it is possible to build a complete workholder by simply combining different sections.

sections and offset T sections. Equal and offset T sections come in 6.00” lengths, or 25.00” lengths. As shown in Figure 4-12, both the equal and offset T sections have basically a square cross-sectional profile where width and height are the same. The major difference between the two styles, as shown, is the position of the vertical member in relation to the horizontal portion. The vertical member of the equal T section is positioned in the middle of the bottom portion. It is moved to one side on the offset T section. Both styles are available in five different sizes ranging from 3.00” x 3.00” to 8.00” x 8.00”. The web thickness of these sections is proportional to the overall size, ranging from .63” to 1.25”. Figure 4-13 shows an application where either style T section can be used.

L Sections.The L-shaped cast section, Figure 4-14, has a right-angle shape and is often used for applications when the bottom portion of a T section might get in the way. As shown, both the vertical and horizontal sides are the same. L sections come in five different sizes ranging from 3.00” x 3.00” to 8.00” x 8.00”, and are available in either 6.00” or 25.00” lengths. The web thickness is proportional to theoverall size.

U Sections.U-shaped cast sections, Figure 4-16, are widely used for channel-type workholders. These sections have a square cross-sectional profile with identical height and width dimensions, as shown. U-sections are available in seven sizes ranging from 1.75” square to 8” square. The web thickness of these sections is, once again, proportional to the overall size. The smaller U sections are made in 19.00” lengths.

The larger sizes are available in full 25.00” lengths. All sizes are available in 6.00” lengths. Figure 4-17 shows two workholders constructed from this type of cast section.

V Sections.V-shaped cast sections, Figure 4-18, are useful when a V-shaped element is needed for either locating or clamping. Thin portions of this material are often used as V pads. Longer lengths are frequently used as V blocks, Figure 4-19. V sections have a rectangular cross section with the width greater than the height. The V-shaped groove is machined to 90º ± 10’. V sections come in three sizes, ranging from 1.00” x 2.00” to 2.50” x 4.00” in standard 6.00” and 18.00” lengths.

Applications include riser elements, supports, or four-sided tooling blocks, as shown in Figure 4-21. Square sections are made in four standard sizes from 3.00” square to 8.00” square. Each size is available in either 6.00” or 25.00” lengths. All external surfaces except the ends are precisely machined.

Rectangular Sections.Rectangular cast sections, Figure 4-22, like square sections, are often used as structure elements in workholders. These sections work well for base elements, riser blocks, or similar features. Rectangular sections come in three standard sizes from 4.00” x 6.0” to 8.00” x 10.00”. Here, too, all external surfaces except the ends are precisely machined. They are available in 6.00 and 25.00” lengths.

H Sections.H-shaped cast sections, Figure 4-23, are a unique design well suited for either complete tool bodies or structural elements. These sections are basically square and come in five sizes ranging from 3.00” x 3.00” to 8.00” x 8.00”. All H sections are made in 6.00” and 25.00” length. Figure 4-24 shows an application with the H section as a tool body.

Flat Sections.Flat cast sections, Figure 4-25, are the simplest and most-basic type of cast section. These sections are used where a cast iron material is preferred over steel flat stock. Flat sections are available in five width and thickness combinations. The sizes range from .63” x 3.00” to 1.25” x 8.00”, and 6.00” and 25.00”

Angle brackets are often used when a right-angle alignment or reference is required. Although angle brackets are commonly thought of as 90º elements, there are also adjustable-angle styles of angle brackets and plates.

Angle brackets are often used when a fixed 90º angle is required. The right angle of these plates is closely controlled and is accurate to 90º ± .08º. These brackets are made in ASTM A36 steel or 6061-T6 aluminum.

Angle brackets come in 10 different sizes ranging from 2.00” x 2.50” to 6.00” x 6.00” with both equal and unequal leg lengths. The web thickness of these sections is also proportional to the overall size, ranging from.22” to .44”.

Figure 4-26.Angle brackets are machined flat and parallel to close tolerances. They are also available with precision locating holes for 3-axis accuracy.

The gusseted angle bracket, Figure 4-27, is a variation of the standard angle bracket. This angle bracket is made with a gusset between the horizontal and vertical legs. The gusset stiffens the angle bracket and reduces any distortion when heavy loads are applied. These angle brackets also have a right angle accurate to 90º ± .08º. These brackets are made in ASTM A36 steel or 6061-T6 aluminum.

Adjustable angle brackets, Figure 4-28, are another variation of the plain angle bracket. These brackets are made with a close-tolerance hinge between the horizontal and vertical legs.

The hinge permits the bracket to pivot so it may be set at any desired angle. The most-basic adjustable angle bracket is the plain type, shown at (a). This type has a bolt and nut arrangement for the hinge. The gusseted adjustable angle bracket, shown at (b), also has a bolt and nut hinge, but it also has a gusset mount on both legs. The mount permits the two legs to be connected with a gusset that is either bolted or welded to the mounts. For applications where the angle bracket must be disassembled, the removable-pin-type adjustable angle can be used. This angle bracket, shown at (c), uses an L pin to attach the horizontal and vertical legs.

These brackets are made of 1018 steel. The plain and gusseted adjustable angle brackets come in three different sizes ranging from 3.00” x 3.00” to 4.00” x 4.00”, with equal or unequal leg lengths. The removable pin type is made in two sizes, 4.00” x 4.00” and 6.00” x 6.00”.

Figure 4-29.The load on a hoist ring is not simply total weight divided by the number of hoist rings. Shallow lift angles can cause very-large resultant forces.

Hoist rings should, for safety reasons, be added to any tool weighing over 30 pounds. The following are design considerations when selecting hoist rings.

The load on each hoist ring is not simply total weight divided by the number of hoist rings. The resultant forces can be significantly greater at shallow lift angles and with unevenly distributed loads. In the example shown in Figure 4-30:

Despite the 5:1 safety factor on hoist rings, never exceed the rated load capacity. This safety margin is needed in case of misuse, which could drastically lower load capacity.

Tensile strength of fixture-plate material should be above 80,000 psi to achieve full load rating. For weaker material, consider through-hole mounting with a nut and washer on the other side.

Tighten mounting screws to the torque recommended. Because screws can loosen in extended service, periodically check torque. For hoist rings not furnished with screws, mount only with high-quality socket-head cap screws.

The mounting surface must be flat and smooth for full contact under the hoist ring. Tapped mounting holes must be perpendicular to the mounting surface.

Standard Hoist Rings.Standard hoist rings, Figure 4-31, have a low profile and are attached directly to the mounting surface with socket-head cap screws. This is the most economical type of hoist ring. The solid forged lifting ring pivots 180º but does not rotate. These hoist rings are available for loads to 20,000 lbs.

Swivel Hoist Rings.Swivel hoist rings, Figure 4-32, are a form of hoist ring with a 180º pivot and 360ºrotation. These hoist rings, available in the two variations shown, are mounted with a single screw. As shown in Figure 4-33, these hoist rings are always preferred over conventional eye bolts or forged lifting eyes when side loads are expected. The pivot-and-swivel combination permits the hoist ring to accommodate lifting angles that can cause a standard eye bolt or forged lifting eye to break. An inherent advantage of the swivel hoist ring when compared to the eyebolt or lifting eye is the ability of the swivel hoist ring to swivel, rather than being fixed in one orientation. Forged lifting eyes and eyebolts have their maximum lifting strength when the axis of the eye is perpendicular to the lifting angle, and when the lifting eye is screwed all the way to the shoulder. It is very difficult to achieve both of these conditions simultaneously. The swivel hoist ring solves those problems easily. These swivel hoist rings are available for loads up to 10,000 lbs. They are available in a wide variety of sizes with either black oxide or electro-less nickel plate finish, and many are available in stainless steel.

A useful hoist-ring accessory is the hoist-ring clip, shown in Figure 4-34. These clips keep the swivel hoist rings stationery and out of the way when they are not being used for lifting.

Other styles of hoist rings are also commercially available. These styles including Heavy-Duty Swivel Hoist Rings, Heavy-Duty Weld Mount Swivel Hoist Rings, and Shackle Hoist Rings. Figure 4-35.

Heavy-Duty Swivel Hoist Rings have a forged steel ring, which pivots 180 degrees and swivels 360 degrees simultaneously to allow lifting from any direction. They have a maximum lifting capacity of 30,000 pounds.

Heavy-Duty Weld Mount Swivel Hoist Rings are, as the name implies, attached by welding, and are available in capacities up to 24,000 pounds. Shackle Hoist Rings are designed for permanent mounting on tooling and equipment. It can be bolted or welded in place. Each of these hoist rings can pivot 180 degrees and swivel 360 degrees simultaneously to allow lifting from any direction. All have a safety factor of 5:1.

Lifting Pins.Lifting pins, Figure 4-36, are a modified form of hoist ring. Sizes are available for loads up to 3,400 lbs. These pins have a positive-locking four-ball arrangement to hold them in place during lifting. A release button at the opposite end of the pin allows quick installation and removal. Figure 4-37 shows two typical applications. These pins are made of 17-4Ph stainless steel.

Threaded inserts are widely used for construction and repair of workholders. The most common use for the inserts is to reinforce threads in new workholders or to repair threads in existing workholders. Threaded inserts provide a way to strengthen threaded holes in new workholders where repeated use may cause excessive wear, such as with aluminum or other soft fixture plates. With existing jigs and fixtures, threaded inserts are a quick way to fix stripped, damaged, or worn threads. Two primary forms of threaded inserts are Keenserts and self-tapping threaded inserts.

Keenserts, Figure 4-38, are threaded inserts for both repairing and reinforcing applications. The Keensert design uses a standard tap size for installing the insert. This feature eliminates the cost of special taps for threading the mounting holes. As shown, the inserts have unique locking keys that both securely hold the inserts in place and prevent rotational movement. The method of installing these inserts is shown in Figure 4-39.

Drill out the old thread, if repairing an existing thread, or drill a new hole to the specified tap drill diameter (slightly larger than the normal tap drill for that thread size).

Keenserts are made in a variety of forms for almost any application. The inserts are available in a heavy-duty carbon-steel style in standard inch sizes from #10 through 1 ½, and in metric sizes from M5 to M20. Stainless steel, heavy-duty, and thinwall inserts are also available in either plain or internal-thread-locking styles. A variety of standard Keensert assortments are also available for UNC, UNF and metric threads, Figure 4-40.

One other style of Keensert, ideal for repair work, is the solid Keensert, Figure 4-41. As shown, these stainless steel inserts are typically used for relocating tapped or drilled holes. They come with external-threaded diameters from 5/16” to 1 3/8”.

An accurate relationship between the workholder and the machine tool must be established. Fixture keys not only establish location initially, they also help hold the fixture in place during machining.

The two basic styles of fixture keys are the slot-mounted and hole-mounted types. Slot-mounted fixture keys are made in two variations, the plain fixture key and the step fixture key, Figure 4-42. The plain fixture key, shown at (a), is the simplest and least expensive of the slot-mounted keys. As shown, these keys are mounted in a slot cut to a depth equal to half the thickness of the key. The key is held in place with a socket-head cap screw.

The second style of slot-mounted fixture key is the step key, shown at (b). These fixture keys are a variation of the standard fixture key. This key’s step design allows a fixture with one slot width to work on a machine table with a different slot width. Like the plain-style key, this key is held in place with a socket-head cap screw.

Fixture 4-43. Sure-Lock™ fixture keys are ideal for small and medium fixtures, while removable locating keys are best for large, heavy fixtures. Subplate locating keys allow mounting the same fixtures on a subplate with 3-axis location.

Hole-mounted fixture keys are also made in several variations. The most popular are the Sure-Lock™ fixture key and the removable locating key, Figure 4-43. Hole-mounted keys eliminate the need to slot fixtures. The Sure-Lock™ fixture key, shown at (a), is the most popular of all fixture keys. Keys for any machine-table slot mount in a .6250” reamed hole for interchangeability. This design has a unique locking arrangement to precisely align and lock the fixture key in the hole. As shown, Sure-Lock™ fixture keys can be secured from either the top or bottom of the fixture. These keys are made in many sizes, for all standard USA table slots from 3/8” to 13/16”, and metric table slots from 12mm to 22mm.

Locating keys, shown at (b), are the standard removable-type fixture key for large, heavy fixtures. These keys can be inserted from above after placing the fixture on the machine table, and then removed again if desired after the fixture is fastened. This design keeps the fixture’s bottom side free of obstructions. Locating keys all mount in a 1.1875” reamed hole. They are available in many sizes, for all standard USA table slots from 9/16” to 7/8”, and metric table slots from 14mm to 22mm.

Subplate locating keys, shown at (c), are designed for mounting quick-change fixture plates on a subplate. A round key and a diamond (relieved) key are used together for precise location without binding. Two standard diameters, .6250” and 1.1875”, match standard fixture-key holes. This allows mounting these same fixture plates either on a subplate (3-axis location) or directly on a machine table (2-axis location).

Pallet Fixture Keys. Fixture keys for mounting tooling plates and blocks on standard DIN pallets. Each pallet requires one center key and one radial key (for orientation). If desired, the radial key can be removed after fastening the pallet to the machine table. A tapped hole in the top of each pin makes insertion and removal easier. Center keys are available for 25, 30, and 50mm holes. Radial keys are available for 20 and 25mm holes. See Figure 4-44.

Figure 4-44. Two pallet fixture keys, one for center location and one for radial orientation, are used for DIN mounting on horizontal machining centers.

Jigs are made to meet the requirements and specifications of individual workpieces, resulting in an infinite number of different jigs. Even though every jig may be different, each can be grouped into one of only a few categories. The following is a description of the basic jigs and the applications where each is best.

Template jigs, Figure 4-45, are the simplest and least-expensive jigs. They are generally used for layout or light machining. They are designed for accuracy rather than speed. Template jigs do not have a self-contained clamping device. If a clamp is needed, a secondary clamp such as toggle piers may hold the jig to the workpiece. When a template jig is used for drilling multiple holes, a pin placed in the first drilled hole can reference the jig.

Plate jigs are very similar in their basic construction to template jigs. As shown in Figure 4-46, plate jigs have a self-contained clamping device. Although many different clamps can be used, a screw clamp is the most-common type with these jigs.

Table jigs are a variation of the basic template or plate jig. The table jig shown in Figure 4-47 is basically a template jig installed on legs. Table jigs are designed for applications where the surface to be machined also locates the workpiece. The location is transferred across the underside of the jig plate and down the legs to the machine table. When designing this type of jig, make sure the area to be drilled is inside the legs to prevent tipping. Although three legs will work, four are recommended with table jigs. Four legs also wobble if a chip is under one leg; three legs do not. The wobble tells the operator to clear the chips from the locating surfaces.

Indexing jigs are for applications where holes must be drilled in a pattern around a center axis. This is done either with an indexing ring holding bushings, or by indexing the part itself. With a separate indexing ring, Figure 4-48, a hand-retractable plunger is frequently used. A ball-plunger can also be used for less critical positioning. Here the work piece itself serves as the indexing ring. With this design, the first hole is drilled and the part rotated to engage the ball-plunger, Figure 4-49. Once located, the part is re-clamped and a second hole is drilled. The indexing is then repeated until all the holes in the part are drilled. The angular position of the ball plunger relative to the drill determines the indexing pattern. So, for four holes, the plunger is located at 90º from the drill, 60º for six holes, 45º for eight holes, and so on.

Multi-station jigs, Figure 4-50, are for repetitive simultaneous operations on several identical parts. In most cases, almost any jig may be used with a multi-station arrangement. As shown, the unique feature of a multi-station jig is the way the jigs are mounted and arranged with respect to the machining stations. In this example, the jig has four stations: #1 is the load/unload station; #2 is for drilling; #3 is the reaming station; and #4 is where the workpiece is counterbored. An indexing arrangement is also included with this jig to accurately position the jigs at each station.

Trunnion jigs, Figure 4-51, are for large, heavy, or odd-shaped workpieces. This type of jig rotates the workpiece on precision bearing mounts called trunnions. Trunnions are made it two basic styles: standard and spherical.

Standard trunnions, Figure 4-52, are available in either locking or revolving styles. With most trunnion jigs, trunnions are typically used in pairs: the revolving trunnion provides a rotating pivot, and the locking trunnion both rotates and locks at any rotational angle. Locking trunnions are locked in place with a friction-cone arrangement engaged by turning the locking handle. Trunnions are intended for low speed rotation, such as when repositioning a fixture to allow proper access to complete a weld.

These trunnions come in two size ranges, small, with a weight limit of 1,500 pounds at a distance of 18 inches from the face, and the larger one, with a weight limit of 2,500 pounds 18 inches out from the face. In pairs, either the weight limit, or the distance can be doubled, but not both. For larger fixtures, either longer or heavier, exceeding these limits will lead to premature failure of the trunnion(s).

Spherical trunnions, Figure 4-53, are a locking trunnion for pipeframe mounting. The spherical bottom aids in precisely aligning the trunnions. Spherical trunnions lock the jig in position by lowering the handle.

Fixtures, like jigs, can be grouped into a few categories. These categories are most often based on the construction of the fixture. Another way to identify a fixture is by the machine it is used with.

The plate fixture is the most basic and most common fixture. The plate fixture is built with a Carr Lock® Fixture Plate, cast flat section, tooling plate, or similar plate material. All locators, supports, and clamps are mounted directly to the plate. As shown in Figure 4-54, a complete plate fixture can be built using on standard, off-the-shelf components.

Angle-plate fixtures are a variation of the basic plate fixture. They are useful when the locating surface is at an angle to the machine table. The two main variations of angle-plate fixtures are the right-angle and modified-angle plate fixtures. Right-angle plate fixtures, Figure 4-55, are constructed at 90º to the base. The modified-angle plate fixtures have an angle other than 90º. The right-angle plate fixtures can be built with tooling blocks, T cast sections, L cast sections, angle brackets, or any comparable material. Adjustable angles or sine plates may be used to build the modified-angle plate fixtures.

All basic workholding principles should be applied to fixtures used for welding operations. The major differences between most welding fixtures and machining fixtures are the locational tolerances and clamping methods. With welding fixtures, weight is often a problem. Many times a fixture is made up of welded sections.

The sections are usually positioned only in the areas where the parts to be joined contact the fixture. Rather than the precision locators found on most machining fixtures, small angle clips, blocs, or similar elements are used as locators.

The clamps for welding fixtures are often toggle clamps. These clamps offer the best combination of design flexibility, holding capacity, and operational speed. In addition, since most toggle clamps move completely clear of the work area when opened, loading and unloading operations are also simplified. Although the clamps may be attached with a screw, in many instances toggle clamps are welded directly to the fixture body.

Locators and supports must be positioned so any workpiece distortion caused by welding heat loosens, rather than tightens, the workpiece in the fixture.

The manipulation of odd shaped, heavy, and/or bulky items for welding, inspection, or assembly can lead to operator fatigue, mistakes and injuries. Manual/hydraulic lifting columns can eliminate these conditions while simplifying the performance of these tasks. Available in lifting capacities from 225 to 1,350 pounds, these columns are easily raised or lowered by pumping a foot pedal, or releasing pressure to position the work at the optimum level for ease and accuracy. See Figure 4-56.

Rotating modules are also available for these columns to allow rotation of the workpiece in either the horizontal or vertical axis. They are available as free rotating modules, or with locks operated either by hand or foot pedal. See Figure 4-57.

Inspection and gaging fixtures are subject to different requirements than machining fixtures, whether inspection is done on a CMM (Coordinate Measuring Machine) or with manual gages. The following are key differences and unique aspects of inspection fixtures:

This page contains information originally published in the Jig & Fixture Handbook, 3rd Edition, Copyright 2016, Carr Lane Manufacturing Co., St. Louis, Mo.

Designed to prevent casing, drill collars, tubing and other tubulars from falling into wellbores, safety clamps are essential in avoiding downtime and fishing expeditions. They are typically installed above slips or spiders during the initial phases of well installation, when string loads are too light to ensure adequate “bite” from slip equipment.

Each individual, flexibly hinged link contains its own tapered slip for gripping. Spring tension maintains contact between the insert and clamp body, but allows the insert relative to the taper to better suspend the load. Should a pipe start to fall, taper mountings within the clamps tighten against the pipe to prevent further movement. Because they feature spring-loaded dies that act as shock absorbers, safety clamps provide additional axial support to prevent the tubular from falling downhole.

Forum offers a wide variety of safety clamps designed to fit tubulars up to 43 inches. Gripping pressure remains uniform around pipes to prevent crushing thin-walled pipes or gouging their surfaces. Adding or removing segments adjusts the gripping diameters by approximately one inch per segment, providing flexible options that accommodate numerous pipe sizes.

Depending on the size of your drilling pipes, Forum offers clamp types C, T, CXL and AMP to ensure a perfect fit while making-up or breaking-out the string.

Historically, genuine ivory has been difficult to obtain, highly sought after and, consequently, an expensive luxury item. In some ways ivory is very similar to precious metals and gemstones. But while gold and silver have carried purity marks and have been closely regulated by governments for centuries, ivory has never been subjected to similar trade laws regarding genuineness or quality. It has never been illegal to sell imitations of ivory. As a result, there are a tremendous number of ivory look-alike objects in the market today. These include present day fakes to 19th century ivory substitutes like celluloid.

Ivory imitations and fakes have dramatically increased since the mid-1970s. This is largely due to laws, beginning with the Endangered Species Act of 1973, which limit commercial ivory trading to protect threatened species like whales and elephants. As additional laws continued to tighten the sale of natural ivory, more and more ivory fakes and substitutes appeared. Most mass produced new ivory look-alike products are honestly sold as imitations at low prices. But some of those pieces, as well as deliberately confusing intentional fakes of old ivory, frequently appear in the antiques market. This article will look at the basic ways to separate genuine ivory from present day simulated ivory as well as older look-alike ivory.

Many people associate the word "ivory" with only elephant tusks but this is not accurate. Ivory comes from teeth as well as tusks of a number of mammals. Tusks are simply large teeth that extend outside the mouth. Elephant tusks, for example, are upper incisors; walrus tusks are upper canines. Tusks and teeth are formed of the same four parts: enamel, cementum, dentine and pulp cavity. These parts are shown in an elephant tusk above but are included in all other forms of ivory regardless of animal species.

The mammals which provide ivory are: 1) elephants (order Proboscidea) which include species alive today (extant) as well as prehistoric elephants now died out (extinct) like mammoths; 2) walrus; 3) whales--sperm, killer and narwhal; 4) hippopotamus and 5) warthog. These groups represent the main sources of commercial ivory used over the years. Small sized pieces of noncommercial ivory have also been obtained from other species such as tusks from most species of wild and domestic pigs and boars and from the teeth of beaver, elk, camel and bears.

Many people rely on the hot needle test for ivory. When touched with a hot needle, genuine ivory chars and turns black; a hot needle will cause artificial material to melt or burn. In our view this test is bad for two reasons: first, it"s destructive to the piece tested, second, it doesn"t tell you the type of ivory you"re looking at. Knowing the kind of ivory you"re dealing with is now extremely important due to the laws banning the sales of whale ivories.

In their book Identification Guide for Ivory and Ivory Substitutes, the National Fish & Wildlife Forensics Laboratory recommends a three step approach to the identification of ivory and ivory imitations. 1) examination with long wave black light; 2) examination of physical features/shapes; 3) look for Schreger angles (crosshatch grain characteristic of elephant ivory). The step-by-step chart on page 42 will guide you through an easy yes or no process of elimination.

Using black light is an important first step because it saves time by ruling out artificial materials. Virtually all plastics and resins fluoresce blue or blue/white under long wave black light regardless of the surface color in ordinary light. Genuine ivory usually fluoresces white but this can vary depending on whether the ivory has a patina. Most natural old patinas fluoresce dull yellow or brown. Be very suspicious of any brightly colored fluorescence such as yellow as this indicates artificial aging in dung, urine or animal fats. Use black light as your first test, not your only test. Black light is useful for eliminating artificial materials but can not alone prove a piece is ivory. Bone, vegetable ivory (cellulose) and glued together ivory dust, for example, all react like genuine ivory under black light.

Ivory is formed by living growing tissue. The direction and forms of growth are unique to each ivory producing species (see illustrations page 41). These unique grain structures have so far been impossible to duplicate in artificial substances like plastics and resins. Generally, grain always runs along the long dimension of a piece of authentic worked ivory.

Attempts to put grain in artificial ivory go back over 100 years. Celluloid, one of the earliest plastics invented in 1868, has a prominent grain. Grain in celluloid and other artificial ivory is usually easy to detect because it normally appears as nearly perfectly parallel lines and shows a definite repeating pattern. Grain in natural ivory is random without any noticeable pattern. A repeating pattern with uniform even lines is almost always a sign of a man-made artificial ivory.

The presence of grain also allows us to eliminate other natural non-ivory materials such as bone and glued together ivory dust. But like the black light test, grain alone does not guarantee a piece is ivory. You must use several tests before you can make an accurate judgement.

The key feature to identifying elephant ivory is a unique pattern of crosshatching that appear in cross sections of elephant tusk. These lines, actually rows of microscopic tubes, are known as Schreger Lines; where they cross form Schreger Angles. Schreger Lines have never been duplicated in artificial plastics or resins. The presence of Schreger Lines always qualifies a piece as elephant ivory. The lines are most easily seen in the bases of figures and anywhere cuts are made at right angles to the grain. While the presence of Schreger Lines can be diagnostic, they may not always be obvious and depending on how a piece of ivory was cut they won"t always show. It is a myth that a piece made of ivory will always have them, so the absence of Schreger Lines cannot be a reliable indicator of a substance other than ivory.

Schreger Angles are used to establish whether ivory is from present day elephants or extinct elephants such as mammoths. This is an important distinction because the sale of extinct elephant ivory is basically unrestricted while the sale of present day elephant ivory is tightly regulated. Schreger Angles of less than 90° indicate mammoth ivory; angles greater than 115° indicate elephant ivory. Use the outer Schreger Angles (closest to the outside edge) only for this test. Do not use Schreger Angles in the center of the tusk. Measure at least five angles to get a true average.

Ivory nuts, which are the hard cellulose kernels from Tagua palms, are frequently confused with genuine ivory. They fluoresce like genuine ivory under black light and show a fine grain under magnification. Although they can grow to the size of a small apple, the majority of ivory nuts are under 2" which makes them unsuitable for large carvings. The most common use of ivory nuts is for new netsuke. The definitive test is to apply a small drop of sulfuric acid. This will form a pink stain on ivory nuts in 10-12 minutes but will not stain genuine ivory. However, use this test as a last resort; the stain is permanent and not removable.

Don"t be misled by surface color in ordinary light. Patina, regardless of color, does not prove either age or whether a piece is genuine ivory. Natural original patinas on genuine ivory can fade completely away in bright sunlight. The surface can fade so much that Schreger Lines and grain become almost invisible.

Large pieces of old ivory commonly form cracks over the years. Some persons incorrectly use cracks as a sign of age or proof that a piece is ivory. This is misleading. Many new pieces of molded artificial ivory have "cracks" and other imperfections deliberately included in the casting.

The critical point to keep in mind is the need for multiple tests. No one test provides an accurate basis for judgement. Under normal circumstances, genuine ivory (with no or little patina) should appear white under long wave black light and genuine ivory always has grain. Elephant ivory always has Schreger Lines, a cross hatch pattern, when seen in cross section. Translucence is an ivory characteristic that can be helpful in differentiating it from bone, as bone is an opaque substance.

Anyone dealing in ivory needs to know the laws regulating its sale, display and transportation. The primary federal laws governing ivory are: The Endangered Species Act, Lacey Act, Convention On International Trade in Endangered Species (CITES), and African Elephant Conservation Act. Copies should be available at larger public libraries and most U.S. Fish and Wildlife offices.

Espinoza/Mann. Identification Guide for Ivory and Ivory Substitut