Screws, Fasteners, and the Design of Nonpermanent Joints

What is the term for the distance between adjacent screw thread forms measured parallel to the thread axis?

What is the key difference between the UN and UNR Unified thread series?

For a square-threaded power screw, what is the correct expression for the torque (TR) required to raise a load F, considering a mean diameter (dm) and lead (l)?

What is the condition for a power screw to be self-locking?

A square-thread power screw has a major diameter of 32 mm and a pitch of 4 mm with double threads. Given f = fc = 0.08, dc = 40 mm, and a load F = 6.4 kN per screw, what is the torque required to raise the load (TR)?

For a inch-series bolt with a nominal diameter (d) and a length (L) of 8 inches, what is the specified thread length (LT)?

What is the primary reason given for why nuts should never be reused?

In a bolted connection, what is the term for the total thickness of the clamped material?

For calculating member stiffness using the pressure-cone method, what half-apex angle 'alpha' is generally used for materials like hardened steel, cast iron, or aluminum?

Using the exponential curve-fit equation km = EdA*exp(Bd/l) and the parameters for gray cast iron from Table 8-8 (A=0.77871, B=0.61616), calculate the member stiffness per bolt (km) for a joint made of gray cast iron with E=14.5 Mpsi, d=0.625 in, and l=1.5 in.

What is the definition of the proof load for a bolt?

For an SAE Grade 5 bolt with a diameter between 0.25 and 1 inch, what is the minimum proof strength?

In a preloaded bolted joint, what is the stiffness constant C?

What is the general relationship for finding the required tightening torque T for a bolt, given the torque coefficient K, desired preload Fi, and nominal diameter d?

For a zinc-plated bolt, what is the recommended torque factor K for use with the equation T = K*Fi*d?

What is the formula for the factor of safety against joint separation, n0?

For nonpermanent connections with reused fasteners, what preload (Fi) is recommended in terms of the proof load (Fp)?

A pressure vessel joint is held by 6 bolts and subjected to a total separating force of 36 kip. The stiffness constant is C = 0.368 and the recommended preload per bolt is Fi = 14.4 kip. What is the load factor guarding against joint separation (n0)?

In a gasketed joint, what is the rough rule for the maximum spacing of adjacent bolts around a bolt circle of diameter Db with N bolts, to maintain uniform pressure?

What is the fatigue stress-concentration factor (Kf) for the fillet of an SAE grade 4 to 8 bolt?

What is the fully corrected endurance strength for an SAE 5 bolt with rolled threads, in the size range of 0.25 to 1 inch?

In a bolted joint subjected to an external load fluctuating between Pmin and Pmax, what is the formula for the alternating stress component (sigma_a)?

For a bolted joint under repeated loading (Pmin = 0, Pmax = P), what is the relationship between the mean stress (sigma_m) and the alternating stress (sigma_a) if the preload stress is sigma_i?

For a bolted joint under repeated loading, what is the formula for the fatigue factor of safety (nf) using the Goodman criterion?

Which failure mode in a shear joint is calculated using a stress based on the projected contact area of the rivet or bolt, A = t*d?

In a bolted joint loaded in shear, where members are made of 1018 cold-rolled steel (Sy = 54 kpsi) and bolts are grade 5 (Sy = 92 kpsi), and the joint consists of two 1-inch thick plates with four 0.75-inch bolts, which failure mode results in the lowest limiting load?

In an eccentrically loaded fastener group, the direct load or primary shear (F') on each of the 'n' bolts is calculated as:

What is the formula for the secondary shear load (F_n'') on a specific bolt 'n' in an eccentrically loaded group with equal diameter bolts?

A cantilevered bar is attached to a channel with four bolts. The shear reaction is V = 16 kN and the moment reaction is M = 6800 N*m. The distance from the centroid to each bolt is r = 96.0 mm. What is the magnitude of the secondary shear force (F'') on each bolt?

In a power screw, how is the bending stress (sigma_x) at the root of the thread calculated, given the load F, root diameter dr, number of engaged threads nt, and pitch p?

In the analysis of stresses in a power screw thread, experiments show that the engaged threads do not share the load equally. What portion of the load does the first engaged thread typically carry?

What does the term 'tensile-stress area' (At) of a threaded rod represent?

How is the stiffness (spring rate) of a fastener (kb) with both an unthreaded portion of length (ld) and a threaded portion of length (lt) calculated?

In a joint with two steel members clamped by a 0.5 in-13 NC steel bolt, the bolt grip is 2 inches. The bolt stiffness (kb) is 2.57 Mlbf/in and the member stiffness (km) is 12.69 Mlbf/in. What is the stiffness constant C?

What is the approximate torque coefficient K for a standard bolt with f = fc = 0.15?

A 0.75 in-16 UNF SAE grade 5 bolt is to be preloaded to 25 kip. Using the standard torque coefficient K=0.2, what is the required tightening torque?

Which part of a bolt is NOT considered a primary point of stress concentration?

What is the yielding factor of safety (np) for a bolted joint?

According to the text, the distribution of typical bolt failures under fatigue loading is approximately 65 percent at which location?

For a bolt under repeated loading (from zero to P), how is the mean stress component (sigma_m) calculated?

In the context of bolted or riveted joints loaded in shear, which of the following failure modes is NOT typically analyzed?

What is the main purpose of using studs in a bolted joint instead of cap screws?

For a metric M12 x 1.75 thread, what do the numbers '12' and '1.75' represent?

In a power screw application, a thrust or collar bearing is employed to handle which component of the load?

What is the primary purpose of using washers under a bolt head?

For a bolt made of ASTM A354, grade BD steel, what is the minimum tensile strength?

How is the resultant bolt load (Fb) related to the preload (Fi) and the portion of the external load taken by the bolt (Pb)?

In an eccentrically loaded shear joint, how are the primary shear (F') and secondary shear (F'') forces combined to find the resultant load on a bolt?

For a bolt with metric property class 9.8 and size M1.6-M16, what is the minimum yield strength?

What is the primary benefit of preloading a bolt in a tension joint?