Ex 3: A double threaded power screw with ACME threads is used to raise a load of 300kN. The nominal diameter is 100mm and the pitch is 12mm. The coefficient of friction at the screw threads is 0.15. Neglecting collar friction, calculate 1- Torque required to raise the load. 2- Torque required to lower the load. 3- Efficiency of the screw.

Ex 3: A double threaded power screw with ACME threads is used to raise a load of 300kN. The nominal diameter is 100mm and the pitch is 12mm. The coefficient of friction at the screw threads is 0.15. Neglecting collar friction, calculate 1- Torque required to raise the load. 2- Torque required to lower the load. 3- Efficiency of the screw.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A 5/8 inch diameter double-thread Acme power screw with a thread coefficient of friction of 0.1 is being used to raise a load of 2,404 Ib. How much does the load move in inches to two decimal places during one full revolution of the power screw ? Selected Answer: 0.08 Correct Answer: 0.25 0.01
Required information For a bolted assembly with six bolts, the stiffness of each bolt is kb 2 Mibf/in and the stiffness of the members is km = 13 Mlbf/in per bolt. An external load of 80 kips is applied to the entire joint. Assume the load is equally distributed to all the bolts. It has been determined to use 1/2 in-13 UNC grade 8 bolts with rolled threads. It is desired to find the range of torque that a mechanic could apply to initially preload the bolts without expecting failure once the joint is loaded. Assume a torque coefficient of K = 0.2. NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Determine the maximum bolt preload that can be applied without exceeding the proof strength of the bolts once the load is applied. The maximum bolt preload that can be applied is Ibf.
Problem parameters for Case #2: Cases Load (lbs) 2 55,000 What is the total Deformation in (in) on the rod? Note: • Give your answer rounded to 3 decimal place i.e. 0.04352 = 0.044 or 0.04342 = 0.043 • Do NOT include any units or other text. The size of your numeric value should be given in (in). i.e. if your answer is 0.043 (in) then enter this as "0.043" (Do NOT enter "0.043 in")
I need the answer as soon as possible
A rigid coupling with 30 inches of bolt circle diameter transmits a torque of 18,000 lb-in. The coupling material has a yield strength of 90,000 psi. The coupling is fastened by six bolts. Assume design factor of N=3 Calculate the diameter of each bolt.
The eye screw, shown in the figure below is subjected to a force of 35 kN. The material of the screw is steel with ??=355 ???. The safety factor is 1,5. Calculate the minimum diameter of the thread.
You have to build a box lifter, this will be made with a square threaded power screw. The power screw is 3 inches in diameter and 2 threads per inch. To improve the speed of raising and lowering the boxes, it must be with triple thread. The coefficient of friction of the screw and collar is 0.25, the diameter of the collar is 4 inches.Calculate:1. The depth of the thread, the width of the face, the average diameter, the root diameter, the pitch and its feed.
An electric motor drives a punch press with a flywheel and is running at 1200 rpm. The torque of the punch press is as follows: a. 0-(10000+10) at first 45deg b. goes to zero for next 45deg c. 0-(6000+10) at next 45deg d. goes to zero for the remainder of the cycle. Employing a Cf of 0.2, a solid steel disc with density of 0.283 lb/in^3, and a thickness of 2 in, determine the flywheel diameter in meters.
A machine vice as shown in figure below ,has a single start square thread with 28 mm nominal diameter and 3 mm pitch. The outer and inner diameters of the friction collar are 62 and 50mm, respectively. The coefficients of friction for thread and collar are 0.3 and 0.3, respectively. The machinist can comfortably exert a force of 240 N on the handle at a mean radius of L= 217 mm. Assuming uniform wear for the collar, Calculate: a-Mean diameter of the screw d. b-Helix angle a. C- Friction angle 4. d-Tightening Torque T in terms of W. e- Friction Torque Tc in terms of W. f-Clamping force developed between the jaws W. g- Overall efficiency of the clamp n. Fixed jaw Moving jaw Screw Frame Handle