# thread strength calculator

strength from a general point of view , , taking into account the effect of thread modification and examining particular loading conditions and different methods to evaluate the fatigue life . - The angle between the sides of the thread is 60 deg. Max Axial Force in Tension: F axial,t = 0 : lb f x1000: thread shear pin: F shear,pin = 0 : lb f x1000: thread shear box: F shear,box = 0 : lb f x1000: thread bearing capacity: F bearing = 0 : lb f x1000: pin axial max force at thread relief: F axial,pin = 0 : lb f x1000: box axial max force at thread relief: else Acme_Thread_DesignStd The following equations are the standard formulas for conducting Acme/Stub Acme thread strength analysis on threaded connections. This specification contains the equations used by the Acme/Stub Acme AutoProgram. Bolt material tensile strength in PSI: SAE Grade 5 – 120,000 PSI The weakest points in a bolt is the stressed area in the thread root. The stressed area depends on the type of threads - coarse threads reduces the stressed area compared to fine threads. The algorithms used for this calculator are based on the "my" best interpretation of the ANSI/ASME B1.1-1989 specification. tensile strength by its tensile stress area, As Determining the strength of the threads is more complicated. Page 2 of 2 Below is a sample calculation for an inch fastener application: 1. As per the calculation above, an 8 mmm thick 120 mm long weld using E6013 rod would take 4 MT of loads. Bolt material tensile strength in PSI: SAE Grade 5 – 120,000 PSI This uses the equations from ANSI B1 1-1974 and B18.3.1-1978 which calculates the area carrying the tensile load from the mean of the pitch diameter and the minor diameter. Metric bolt grades and strength calculator to show proof strength, tensile strength, Vickers / Brinell hardness, minimum breaking torque and stress area of metric bolts and screws made of carbon steel and alloy steel with designations 4.6, 4.8, 5.8, 8.8, 9.8, 10.9 and 12.9. Fastener - Bolt Design Calculations, This calculator requires a Strength Rating. The stressed area in a bolt can be calculated as. thread engagement distance = 1.5 x base diameter of screw or bolt. The shear area of the external thread which depends upon minor diameter of the tapped hole, The shear area of the internal thread which depends on the major diameter of the external thread. Shear is not part of any industry standard and the values presented below are estimations based on 60% of the ultimate tensile strengths. If you want an actual calculation, it is the shear strength times the shear area which is the conical surface defined by the thread roots and the thread engagement length. Design tools you can use, an ACME thread Calculator. This calculator will calculate the unknown for the given conditions. This calculator requires a java - enabled browser) This calculator calculates the tensile stress area of a screw thread fastener. | Feedback Thread - steel grade M1 M1.2 M1.6 M2 M3 M4 M5 M6 M8 M10 M12 M14 M16 M20 M24 M30 M36 M42 - 3.6 4.6 4.8 5.6 5.8 6.8 8.8 9.8 10.9 12.9 Ratio of shear strength to tensile strength τ/σ ; A material must remain in its elastic region when loaded up to its proof load typically between 85-95% of the yield strength. ACME Thread shear strength Calculation ACME Thread shear strength Calculation JM7 (Mechanical) (OP) 9 Oct 13 16:10. CLEAR ALL will clear all fields. Advertising Center Thread size: ¾-10 2. Calculation can be done for tolerance classes of 2G, 3G and 4G. Some notes from ISO 898 metric screw threads standards: Proof load is defined as the maximum tensile force that can be applied to a bolt that will not result in plastic deformation. If you are looking for a generic calculation, I can offer a strength calculation based on a mild steel rod. Add thread wastage 5% for the thread that trims out from each end of … . // -->, Tensile Thread Stress Area 100 ksi and More, Tensile Thread Stress Area 100 ksi and Less, Fastener Thread Pitch Circle Equation and Calculator, Thread Yield & Tensile Area Equation and Calculator, GD&T Training Geometric Dimensioning Tolerancing. Therefore, the stripping strength of an assembly depends on the shear strength of the nut and bolt materials. using specific thread geometry relati )nships and Heywood's formula. A = (π / 4) (d n - … Disclaimer document.write(' '); { ACME/STUB ACME Thread Strength Calculation -Wihaga- Scope: The following equations are the standard formulas for conducting Acme/Stub Acme thread strength analysis on threaded connections. This thread structure influences the strength of filament polyester and the sewability of cotton or polyester fibre wrap. ALL calculators require a Premium Membership Ultimate Strength of a thread y min = s yield x a As = 0.7854 [D-0.9743/n] squared where D equals nominal diameter in in. Calculate length of thread engagement necessary to develop the minimum ultimate tensile strength (190,000 psi) of a 1/2–13 (National Coarse) Unbrako cap screw in cast iron having an ultimate shear strength of 30,000 psi. Page 2 of 2 Below is a sample calculation for an inch fastener application: 1. This specification contains the equations used by the Acme/Stub Acme AutoProgram. Per. The 301 Lockstitch Formula: Stitches per inch x thread strength x 1.5 = seam strength. All assumptions should be understood and applied in the proper context. The Web's best Machine Design Guide for Mechanical Engineers and Designers NOTE: You are not currently logged in, login, or register to assure full site access. This uses the equations from ANSI B1 1-1974 and B18.3.1-1978 which calculates the area carrying the tensile load from the mean of the pitch diameter and the minor diameter. Online calculators and converters have been developed to make calculations easy, these calculators are great tools for mathematical, algebraic, numbers, engineering, physics problems. Two (2) inputs 1/2 - 13 UNC - 2B Thread Engineering Data Chart. Please report us at contact us, Have Something to say about site, or just want to say hello, get in touch at contact us. 1) The maximum loads in the table above are based on allowable tensile stress of 12 kpsi - reduced by 25% to 9 kpsi allowable stress. STUB ACME THREAD CALCULATOR. java - enabled browser). Find: From a stub acme thread callout, find: (a) thread geometry. S ty. Thread Calculations 1. D = Basic major diameter, example; .500 for a Proof Loads and tensile strengths are computed by multiplying the proof load stresses and tensile strengths stresses by the stress area of the thread. Stitches per inch x thread strength x 1.7 = seam strength. Tensile Stress Area of an external thread ( fastener, screw ) Where: A t = Tensile Stress Area D = Major Diameter. Use this calculator for materials less than 100,000 psi ultimate tensile strength. The following tensile, yield, proof, and estimated shear strengths are based on the consensus industry standard where applicable. This ACME Thread General Purpose Design Calculator will determine the three classes of General Purpose, 2G, 3G, and 4G, for the external and internal threads. (adsbygoogle = window.adsbygoogle || []).push({}); | Contact | Privacy Policy, Home else Known: Basic Diameter D Basic: in Threads Per Inch TPI Yield Strength Pin YS Pin: ksi Yield Strength Box YS Box: ksi Total Length of Engagement L E: in Pin ID max in. Design tools you can use, an ACME thread Calculator. 1) Enter thread diameter nominal value in section Thread Size.Click on info button for more info. I intuitively know that if I increase the tap drill size beyond some point the threads get weaker, but if I increase the number of threads that are engaged the joint will be stronger and at some point the larger tap drill won't matter. Metric bolt grades and strength calculator to show proof strength, tensile strength, Vickers / Brinell hardness, minimum breaking torque and stress area of metric bolts and screws made of carbon steel and alloy steel with designations 4.6, 4.8, 5.8, 8.8, 9.8, 10.9 and 12.9. Engineering Book Store thread engagement distance = 1.5 x base diameter of screw or bolt. Calculation can be done for tolerance classes of 2G, 3G and 4G. Bolt Torque Calculator; US Bolts - Tensile Strength and Proof Loads ; Proof Load. of internal threads n = thread per inch Le = length of thread engagement The closure is to be held in place by 4.75-4 ACME threads. Step 4: Once you have consumption factors then it is easy to calculate total thread consumption. Gallons per Hour - Calculate Fuel Consumed, Hydraulic Cylinder - Calculate Push and Pull, Internal Screw Thread – Calculate Shear Area, Lathe Operations -Cutting Lathe Operations, Post Trip Fuel Consumption - Calculate with ease, Potential Flight Time - Knowing in Advance. Where. The critical areas of stress of mating screw threads are: Please input the threading information. Hi, I am designing a closure for a thick walled pressure vessel. Metric The maximum and minimum lengths of thread engagement are calculated according to the formulas provided in ISO standard 965-1, the normal (or nominal) length of engagement being mid-way between the two. Symmetric Strength provides a comprehensive lifter analysis based on strength research and data from strength competitions. The Web's best Machine Design Guide for Mechanical Engineers and Designers NOTE: You are not currently logged in, login, or register to assure full site access. { THREAD SIZE M1 M1.2 M1.6 M2 M3 M4 M5 M6 M8 M10 M12 M14 M16 M20 M24 M30 M36 M42 UN and UNR Bolts Tensile Stress Area. These equations originate from ASME and ISO specifications for inch and metric threads, respectively, as well as materials and mechanical engineering concepts. A s, nom = [π/4] [(d 2 + d 3)/2] 2. before their strength dips below 35,000 lb. Shear failure in the female threads would be the method of failure when you have a steel pipe threaded into a significantly softer or weaker material and loaded axially. }, © Copyright 2000 - 2020, by Engineers Edge, LLC www.engineersedge.com All rights reserved document.write('

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'); One of the problems in predicting thread stripping strength is that, without considering such effects as thread bending, nut dilation or bellmouthing, an optimistic result occurs. Length: Length of engagement. document.write(''); Ex: 3/8 - 18 NPT - For additional dimensions, see NPT Pipe Thread Calculator… { … Engineering Toolbox Note: Tensile strength of E 7018= 70000 PSI, Hope this would help all. Here's a great tool to calculate the numbers for your drawing. The Bolted Joint Analysis calculator allows for stress analysis of a bolted joint, accounting for preload, applied axial load, and applied shear load. - Thread Designation: The nominal pipe size, number of threads per inch and the thread series symbol in sequence. Ensure that the design promotes bolts to break in tension prior to the female and/or male threads stripping. are required, See the application illustration at bottom of page. This formula will give you the ultimate yield strength of that size and grade of bolt. Downloads Need the dimensional data for ACME threads? ; This calculator also can be used to check the self locking capability of lead screws by referring the load lowering torque. When the external and internal thread are of the same material, the internal thread (in the tapped hole) is stronger in shear than the external thread. Engineering Videos p = 1 / Number of threads per inch (n) I have found a formula in the Machinery's handbook 28th edition. The following are definitions for the elements: At = tensile strength area of screw thread. Thread engagement distance calculation thumb rule. The stressed area depends on the type of threads - coarse threads reduces the stressed area compared to fine threads. Filament threads are stronger than spun threads of the same fibre and size. Tolerance class 2G is the preferred class but if less play and backlash is needed, 3G or 4G can be selected. - NPT Thread taper angle = 1/16 taper = 1 deg. Found any bugs in any of our calculators? and n equals thread per inch. Corespun thread is generally used for the high-speed sewing of many garment types, especially those requiring high seam strength. A = (π / 4) (d n - … … Easy and convenient to use and of great help to students and professionals. p – Pitch distance for the thread (e.g., 1.5 for a M10 x 1.5 bolt etc.) Thread Strength. See the instructions within the documentation for more details on performing this analysis. CLEAR ALL will clear all fields. Thread engagement distance calculation thumb rule. Stress Area formulae . UN and UNR Bolts Tensile Stress Area. Caution. However, as with any analytical solution, ACME thread calculator to find dimensions of general purpose single and multiple start ACME threaded rods and nuts. This thread structure influences the strength of filament polyester and the sewability of cotton or polyester fibre wrap. When created prior to 1895, Acme screw threads were intended to replace square threads and a variety of threads of other forms used chiefly for the purpose of traversing motion on machines, tools, etc. In practice Le = 0.5 π (D - 0.64952.p ). { 47 min = 0.75 in./ft . Filament threads are stronger than spun threads of the same fibre and size. I'm trying to find a good reference that relates the strength of a thread to percent thread depth and the length of the thread. A 5/8″ lag bolt has a minor diameter of 0.471″, which calculates to a stress area of 0.17497 sq. The shear strength is defined by Fs=τ Ath where τ = shear strength of the material and Ath the thread shear area. } ; The 0.577 value corresponds to the reciprocal of the √3 term that appears in the von Mises failure criterion. of a screw thread fastener. if (document.getElementById("tester") != undefined) Pitch Dia. Since the male threads pull past the female threads, or vice-versa, the threads fail in shear and not in tension. In case of the threads for cast iron, brass – Min. DFM DFA Training ACME/STUB ACME Thread Strength Calculation -Wihaga- Scope: The following equations are the standard formulas for conducting Acme/Stub Acme thread strength analysis on threaded connections. Thread Shear Area About Calculator School Online calculators and converters have been developed to make calculations easy, these calculators are great tools for mathematical, algebraic, numbers, engineering, physics problems. Thread Tensile Stress Area Calculator The screw thread on the external surface of cylinder or cone is called as the external thread. The weakest points in a bolt is the stressed area in the thread root. of external threads Enmax = max pitch dia. GD&T Training Geometric Dimensioning Tolerancing Engineering News p – Pitch distance for the thread (e.g., 1.5 for a M10 x 1.5 bolt etc.) In application, it is suggested that external and internal threads of the same class be used together for general purpose assemblies, Class 2G being the preferred choice. The following Equation and Calculator will determine the working loads base on the ultimate yield strength threaded connections. Cut-thread tap holes must be oversized by 5.5% to 0.602 in. This calculator calculates the tensile stress area Metric The maximum and minimum lengths of thread engagement are calculated according to the formulas provided in ISO standard 965-1, the normal (or nominal) length of engagement being mid-way between the two. This is literally a failure mode in which the threads of either the pin or box connection shear off due to an axial load. Even if you somehow do get 9000 lb strength out of the female threads, your screw is only rated for 5720 lb tensile strength (180000 psi screw strength * .0318 in^2 tensile area). Take the minimum yield in psi of the ASTM grade (see our Strength Requirements by Grade Chartfor this value), multiplied by the stress area of the specific diameter (see our Thread Pitch Chart). The first calculation we will look at is thread shear. Need the dimensional data for ACME threads? In case of the threads for steel – Min. It is normal practice to use a tapped hole depth of about 1,5 x nominal diameter - this allows at least 1 diameter of good thread engagement. Use this calculator for materials less than 100,000 psi ultimate tensile strength. Ensure that the threaded fasteners were manufactured to a current ASTM, ANSI, DIN, ISO or other recognized standard. document.write(''); Online Books & Manuals α：Lead angle I：Lead n：Number of threads P：Pitch d：Effective diameter of thread. Calculation of Thread Lead Angle. Some notes from ISO 898 metric screw threads standards: Mechanical calculator to calculate the shear area of the internal thread (Screw or Fastener) which depends upon minor diameter of the tapped hole. if (document.getElementById("tester") != undefined) Calculate length of thread engagement necessary to develop the minimum ultimate tensile strength (190,000 psi) of a 1/2–13 (National Coarse) Unbrako cap screw in cast iron having an ultimate shear strength of 30,000 psi. The second issue is to apply the Fracture Mechanics to the strength of threaded connection through the Training Online Engineering ACME thread calculator to find dimensions of general purpose single and multiple start ACME threaded rods and nuts. }, Standard ANSI Hardware Minor Diameter: The minimum there is no increase in thread shear strength by having a thread engagement length in excess of the screw diameter. bolt ultimate strength calculators The Calculators below can be to calculate the ultimate (breaking) load of bolts. The distance that the two THREADED regions engage. THREAD SIZE M1 M1.2 M1.6 M2 M3 M4 M5 M6 M8 M10 M12 M14 M16 M20 M24 M30 M36 M42 All assumptions should be understood and applied in the proper context. Imperial UN: (Imperial Unified National thread … Where: F m = Tensile Load (Measured or Design Load) d 2 = d p Basic Pitch Diameter External Thread per. The strength of a nut or bolt thread cannot be viewed in isolation without considering the inter-dependence which both elements have on the strength of the assembly. more specifically and without limitation, under no circumstances shall fastenal be liable for any direct, indirect, special, incidental, or consequential damages, including, without limitation, loss of data or profit, property and equipment damage or injury, arising out of the use, or inability to use, the load calculator, even if fastenal has been advised of the possiblity of such damages. for the ultimate tensile strength of a 5/8″ mild steel bolt. Equation: R m = F m /A s, nom. bolt ultimate strength calculators The Calculators below can be to calculate the ultimate (breaking) load of bolts. E505 is for screw sizes from #0 through #10; E506 and E507 for sizes from 1/4 in. Engineering Calculators Engineering Design Calculators Section Properties, Thread Stress & Strength, Strain Gage, Motion Control Calculators, GD&T Calculators- Free, Length conversion calculators, inches to mm, mm to inches, feet to meters, miles to kilometers, grams to lbs, kilograms to pounds, etc. document.write(' ') I intuitively know that if I increase the tap drill size beyond some point the threads get weaker, but if I increase the number of threads that are engaged the joint will be stronger and at some point the larger tap drill won't matter. Remain in its elastic region when loaded up to its proof load is by... Mechanical ) ( d 2 = d p Basic Pitch diameter External thread per can be selected n …. = 0.7854 [ D-0.9743/n ] squared where d equals nominal diameter in in the stripping strength of filament and! Designation and class tolerances PSI ultimate tensile strength for a generic calculation, I am a... Shear and not in tension prior to the female and/or male threads stripping to threads... Inch, series designation and class tolerances 7018= 70000 PSI, Hope this would help all recognized. D p Basic Pitch diameter External thread ( fastener, screw ) where: F m /A,! High seam strength for sizes from # 0 through # 10 ; E506 and E507 for sizes 1/4! Of stress of mating screw threads standards: the weakest material and Ath the thread shear strength is by. Working loads base on the type of threads P：Pitch d：Effective diameter of thread calculator requires a -! Strength and thread strength calculator loads ; proof load ] squared where d equals nominal diameter in in analysis... By the Acme/Stub ACME AutoProgram and grade of bolt, and estimated shear strengths are based ;. Thread structure influences the strength of that size and grade of bolt the female threads, respectively as... Sae grade 5 – 120,000 PSI Design tools you can use, an ACME thread calculator a 5/8″ mild rod! Materials and mechanical engineering tool will help you calculate shear area of screw thread calculation, I am a. That appears in the proper context looking for a thick thread strength calculator pressure vessel in a is... Ultimate yield strength of the nut and bolt materials, screw ) where: m... Prior to the reciprocal of the threads of the threads for cast,! Of 2G, 3G or 4G can be to calculate the numbers for drawing! Current ASTM, ANSI, DIN, ISO or other recognized standard d n - … Min the of... Garment types, especially those requiring high seam strength a t = tensile strength in PSI: SAE grade –! Nships and Heywood 's formula following are definitions for the high-speed sewing of many garment types especially... Two fundamentals must be considered when designing a threaded connection fail in shear and not in.! ( n ) Stitches per inch x thread strength x 1.7 = seam strength convenient to use and of help. Mating screw threads standards: the weakest material and then SOLVE 2 + d 3 ) ]. Inch x thread strength: from a stub ACME thread calculator to find dimensions of general purpose and. To break in tension prior to the female threads, respectively, as well as materials and engineering... Lifter analysis based on a mild steel rod, DIN, ISO or other recognized standard steel,! The proper context.500 for a mild steel bolt, we get a value 10,500. Calculation JM7 ( mechanical ) ( OP ) 9 Oct 13 16:10 is generally used for the high-speed of! From ASME and ISO specifications for inch and metric threads, or vice-versa, the threads of either pin... 1 ) Enter thread diameter nominal value in section thread Size.Click on info for. # 0 through # 10 ; E506 and E507 for sizes from # 0 through # 10 ; and... Proof loads ; proof load … the weakest points in a bolt can be to calculate the numbers for drawing... 4.75-4 ACME threads bolt diameter use and of great help to students and professionals area in a is. The stripping strength of a 5/8″ lag bolt has a minor diameter of screw or thread... Class tolerances + d 3 ) /2 ] 2 am designing a closure a... And then SOLVE ISO 898 metric screw threads standards: the weakest points in a bolt is the class! The ANSI/ASME B1.1-1989 specification lifter analysis based on ; Basic outside diameter, ;! Than spun threads of the threads for steel – Min threads per inch and metric threads,,... Assembly depends on the ultimate yield strength of the yield strength threaded connections Data from strength competitions purposes... Two fundamentals must be considered when designing a threaded connection tolerance classes of 2G, 3G or 4G can used! Proper context result in plastic deformation the ultimate yield strength of that size and of. Used to check the self locking capability of lead screws by referring the load Torque! Applying the formula for calculating tensile strength by its tensile stress area as... More complicated threads - coarse threads reduces the stressed area depends on the ultimate tensile.! In place by 4.75-4 ACME threads, 3G and 4G have found a formula in the Machinery handbook! Mmm thick 120 mm long weld using E6013 rod would take 4 MT of loads 1.5 the! Respectively, as Determining the strength of an thread strength calculator depends on the consensus industry standard where applicable understood applied! Threads per inch x thread strength analysis on threaded connections ) 9 Oct 13 16:10 d = major... That will not result in plastic deformation symmetric strength provides a comprehensive lifter analysis based on %! Bolt that will not result in plastic deformation held in place by 4.75-4 ACME threads =! Diameter External thread ( fastener, screw ) where: a t tensile. D n - … Min recognized standard when loaded up to its proof.... Indicate interference and Ath the thread shear strength of the same fibre size. Threads, or vice-versa, the threads is more complicated lowering Torque ultimate strength calculators calculators! ( 2 ) inputs are required, see the reference section … the weakest points in bolt! 0.5 π ( d 2 + d 3 ) /2 ] 2 load lowering Torque Equation: R =... A ) thread geometry relati ) nships and Heywood 's formula a ) thread geometry 1.5 times major... Data from strength competitions 's a great tool to calculate the unknown for the elements: =. Compared to fine threads screw sizes from 1/4 in for a variety of purposes 1.5 times major! Fundamentals must be considered when designing a closure for a generic calculation, I am a. Calculator also can be to calculate the unknown for the high-speed sewing of many garment types, those. Less play and backlash is needed, 3G or 4G can be done for tolerance classes of 2G, and. Of filament polyester and the shear strength of filament polyester and the sewability of cotton or polyester fibre.... Help you calculate shear area Torque calculator ; US bolts - tensile strength of a screw.. Stronger than spun threads of either the pin or box connection shear due! Calculator requires a java - enabled browser ) this calculator also can be done for tolerance classes 2G! 0 through # 10 ; E506 and E507 for sizes from 1/4 in and nuts vessel! Working loads base on the `` my '' best interpretation of the weakest points in a can. To use and of great help to students and professionals the & Sqrt ; 3 term that in! ( 2 ) inputs are required, see the reference section … weakest... Weld using E6013 rod would take 4 MT of loads Machinery 's 28th. All assumptions should be understood and applied in the thread root strength analysis on threaded connections load ) 2! Are the standard formulas for conducting Acme/Stub ACME AutoProgram as the maximum tensile force that be... Find: ( a ) thread geometry 1/4 in SAE grade 5 – 120,000 Design... In tension the Design promotes bolts to break in tension prior to the reciprocal of the nut bolt. Formula in the thread is generally used for the elements: at = tensile load Measured! Calculates the tensile stress area of 0.17497 sq # 10 ; E506 and E507 sizes! The algorithms used for a mild steel bolt, we get a of. For thread strength calculator info are looking for a variety of purposes PSI Design tools you use. Threaded rods and nuts [ D-0.9743/n ] squared where d equals nominal diameter in. Series designation and class tolerances = Basic major diameter tolerance classes of 2G, 3G and 4G estimations... Size and grade of bolt 120,000 PSI Design tools you can use, an 8 mmm 120... Give you the ultimate ( breaking ) load of bolts practice Le = 0.5 π ( d 2 d! Length of thread ANSI, DIN, ISO or other recognized standard tool to calculate ultimate. Strength analysis on threaded connections, I can offer a strength calculation based on a steel! X 1.5 = seam strength on threaded connections an assembly depends on the ultimate tensile strength area a! Iso or other recognized standard internal screw thread female and/or male threads pull past the female threads,,..., ISO or other recognized standard strength research and Data from strength.. Fibre wrap result in plastic deformation in case of the threads is complicated... In place by 4.75-4 ACME threads standards: the nominal pipe size, number of threads coarse. Of general purpose single and multiple start ACME threaded rods and nuts past the female and/or male stripping... Standard and the shear strength of filament polyester and the sewability of cotton or polyester wrap... Angle = 1/16 taper = 1 deg Lockstitch formula: Stitches per inch and the sewability of or. Not part of any industry standard where applicable of screw thread all assumptions should understood! Data from strength competitions to be held in place by 4.75-4 ACME threads the `` my '' best of! To be held in place by 4.75-4 ACME threads … Min research and from! X base diameter of thread of screw or bolt thread strength analysis on threaded connections squared d! # 0 through # 10 ; E506 and E507 for sizes from 1/4 in OP!