Installation of TA Thread-Rolling Screws for Metals


TECHNICAL BULLETINInstallation of TA Thread-Rolling Screws for MetalsTA thread-rolling screws are an excellent choice for usewith drilled, extruded, punched or molded holes in ductilemetals and castings. The triangular out-of-round shapeforms strong threads by work-hardening the metal hostmaterial without creating unwanted chips or slivers. The design requires low installation torque and providesexcellent resistance to loosening caused by vibration.

Recommended Hole Diameters for Cold-Rolled Steel Sheets and Plates

All dimensions in inches
ApplicationLightMedium-LightMedium-HeavyFull StrengthExtra Strength
ThreadEngagement Percentage90%85%80%75%70%
ThreadMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameter
2-56.017-.034.0756.034-.052.0761.052-.073.0767.073-.095.0773.095-.169.0779
4-40.022-.045.0974.045-.067.0982.067-.095.0990.095-.126.0998.126-.157.1006
6-32.028-.066.1197.066-.083.1207.083-.117.1218.117-.152.1288.152-.193.1238
8-32.033-.066.1457.066-.098.1467.098-.141.1478.141-.180.1488.180-.230.1498
10-24.038-.079.1656.079-.114.1670.114-.162.1683.162-.209.1697.209-.266.1710
10-32.038-.079.1717.079-.114.1727.114-.162.1738.162-.209.1748.209-.266.1758
12-24.043-.086.1916.086-.130.1930.130-.184.1943.184-.238.1957.238-.302.1970
1/4-20.050-.100.2208.100-.150.2224.150-.213.2240.213-.275.2256.275-.350.2273
All dimensions in millimeters
ApplicationLightMedium-LightMedium-HeavyFull StrengthExtra Strength
ThreadEngagement Percentage90%85%80%75%70%
ThreadMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameterMaterialThicknessHoleDiameter
M2 .5 x 0.450.5-0.92.240.9-1.52.251.5-2.12.272.1-2.72.282.7-3.52.30
M3 x 0.50.5-1.12.711.1-1.72.721.7-2.72.742.7-3.32.763.3-4.02.77
M3.5 x 0.60.6-1.43.151.4-2.03.172.0-2.93.192.9-3.83.213.8-4.53.23
M4 x 0.70.8-1.43.591.4-2.43.612.4-3.33.643.3-4.43.664.4-5.53.68
M5 x 0.81.0-2.14.532.1-2.94.562.9-4.44.584.4-5.94.615.9-7.14.64
M6 x 11.2-2.45.422.4-3.65.453.6-4.95.484.9-6.95.516.9-8.15.55
(1) Hole diameters are based on a calculation of .6495 x thread pitch x % thread engagement. PENCOM strongly recommends testing in the application to determine actual working dimensions.

Performance Data for Cold-Rolled Steel Sheets and Plates

All dimensions in inches unless noted
ThreadMaterialThicknessHoleDiameterNearestDrill SizeThreadFormingTorque(in-lbs)Prevailing FirstRemovalTorque(in-lbs)Rec.AssemblyTorque(in-lbs)FailureTorque(in-lbs)
2-56.0469.0751.9mm1-2.5-146-73
.0625.076#481.2.5-148-103
.0938.079#471.2.5-1511-144
4-40.0312.098#402-31-268-113
.0625.1022.6mm3-41-2915-183
.0938.1022.6mm3-41-21122-27 4
6-32.0625.120#314-73-41425-30 3
.0938.120#316-93-52035-45 5
.1250.1251/86-94-62239-45 4
8-32.0938.147#2610-135-73065-75 3
.1250.1503.8mm11-144-74575-85 5
.1875.1503.8mm16-208-114575-95 4
10-24.0938.17211/6414-185-83565-80 3
.1250.17211/6414-185-84580-90 3
.1875.17211/6417-229-1355110-115 4
10-32.0938.173#1711-149-133580-95 3
.1250.177#1612-169-1350110-120 3
.1875.177#1619-2512-1670115-140 3
12-24.1250.196#919-249-126595-115 3
.1875.199#821-269-1375135-155 3
.2500.20313/6421-2610-1485150-170 4
1/4-20.1250.2245.7mm30-3618-2585170-195 3
.1875.2245.7mm45-5525-35125205-235 4
.2500.228#155-6525-35125205-235 4
  1. Values determined under laboratory conditions using carbon steel hex washer head screws zinc plated and wax coated driven into cold-rolled steel members at low speeds. PENCOM strongly recommends testing in the application to determine actual working performance values.
  2. Recommended assembly torques represent approximately 30-50ksi clamping pressure.
  3. Failure most likely a result of threads stripping.
  4. Failure most likely a result of screw breakage.
  5. Failure most likely a result of threads stripping or screw breaking.

Performance Data for Cold-Rolled Steel Sheets and Plates (Cont.)

All dimensions in millimeters unless noted
ThreadMaterialThicknessHoleDiameterNearestDrill SizeThreadFormingTorque(N-m)Prevailing FirstRemovalTorque(N-m)Rec.AssemblyTorque(N-m)FailureTorque(N-m)
M3 x 0.51.02.71#360.30-0.450.15-0.301.01.5-2.0 3
2.02.752.75mm0.35-0.550.15-0.301.01.6-2.5 3
3.02.752.75mm0.50-0.800.25-0.401.62.5-3.5 5
M4 x 0.72.03.603.6mm0.60-0.850.30-0.401.82.8-3.8 3
3.03.66#270.90-1.30.50-0.703.35.5-7.5 5
4.03.66#271.2-1.60.60-0.854.37.0-10 5
M5 x 0.82.54.57#151.3-2.00.60-0.802.85.3-8.0 3
3.54.57#151.5-2.70.90-1.56.010-12 3
5.04.604.6mm2.0-3.00.90-1.57.011-14 5
M6 x 13.05.41#32.0-2.80.60-1.25.09.0-13 3
4.55.505.5mm3.2-4.50.90-1.510.016-21 3
6.05.505.5mm3.5-4.81.0-1.710.018-25 5
  1. Values determined under laboratory conditions using carbon steel hex washer head screws zinc plated and wax coated driven into cold-rolled steel members at low speeds. PENCOM strongly recommends testing in the application to determine actual working performance values.
  2. Recommended assembly torques represent approximately 207-345MPa clamping pressure.
  3. Failure most likely a result of threads stripping.
  4. Failure most likely a result of screw breakage.
  5. Failure most likely a result of threads stripping or screw breaking.

Recommended Extruded Hole Diameters for Light-Gauge Carbon Steel

All dimensions in inches
MaterialThickness.02.03.04.06.09.13.16.19
ThreadHole Diameter
6-32.118-.120.118-.121.120.120-.123.122-.125
8-32.140-.150.140-.150.150.150.147-.150.148-.152
10-24.160-.170.160-.170.164-.167.165-.168.166-.170.168-.173
10-32.170-.172.170-.173.171-.174.172-.175.173-.176.174-.177
12-24.190.190.190-.193.191-.194.192-.196.193-.197.195-.200.198-.203
MaterialThickness.04.06.09.13.16.19.22.25
ThreadHole Diameter
1/4-20.218-.220.218-.221.219-.223.221-.225.224-.228.227-.231.228-.233.230-.235
(1) Dimensions are suggestions only. PENCOM strongly recommends testing in the application to determine actual working dimensions.

Recommended Extruded Hole Diameters for Light-Gauge Carbon Steel (Cont.)

All dimensions in millimeters
MaterialThickness0.50.81.11.62.43.64.4
ThreadHole Diameter
M2.5 x 0.452.21-2.242.22-2.262.25-2.282.27-2.30
M3 x 0.52.68-2.712.71-2.742.74-2.772.77-2.802.80-2.83
M3.5 x 0.63.11-3.153.13-3.183.16-3.213.19-3.243.24-3.293.27-3.32
M4 x 0.73.55-3.593.58-3.623.60-3.653.64-3.683.69-3.73
M5 x 0.84.48-4.534.51-4.564.54-4.594.57-4.62
M6 x 15.35-5.425.38-5.455.41-5.485.44-5.515.49-5.56
(1) Dimensions are suggestions only. PENCOM strongly recommends testing in the application to determine actual working dimensions.

Recommended Dimensions for Extruded Light-Gauge Carbon Steel

All dimensions in inches
HoleDiameterMaterial Thickness T
.024-.035.042-.048.060.090.106.122
HRHRHRHRHRHR
.081-.100.040.005.040.005.040.006.043.010
.101-.130.047.005.047.005.047.006.052.010.054.010
.131-.150.053.005.053.005.053.006.060.010.063.010.072.013
.151-.180.060.005.081.006.070.010.075.010.087.013
.181-.220.070.005.070.006.090.010.095.010.104.013
.221-.260.075.006.100.010.105.010.120.013
.261-.300.083.006.116.010.125.010.140.013
.301-.340.130.010.140.010.164.013
.341-.380.140.010.155.010.170.013
.381-.430.150.010.170.010.184.013
All dimensions in millimeters
HoleDiameterMaterial Thickness T
0.61-0.891.07-1.221.522.292.693.10
HRHRHRHRHRHR
2.06-2.541.020.131.020.131.020.151.090.25
2.57-3.301.190.131.190.131.190.151.320.251.370.25
3.33-3.811.350.131.350.131.350.151.520.251.600.251.830.33
3.84-4.571.520.131.550.151.780.251.910.252.210.33
4.60-5.591.780.131.780.152.290.252.410.252.640.33
5.61-6.601.910.152.540.252.670.253.050.33
6.63-7.622.110.152.950.253.180.253.580.33
7.65-8.643.300.253.560.253.910.33
8.66-9.653.560.253.940.254.320.33
9.68-10.923.810.254.320.254.670.33
(1) Dimensions are suggestions only. PENCOM strongly recommends testing in the application to determine actual working dimensions.

Recommended Dimensions for Extruded Light-Gauge Carbon Steel (Cont.)Recommended Hole Dimensions for Aluminum and Zinc Die-Castings

All dimensions in inches
ThreadCast HoleDiameter 1CastBossDiameterC Min.DrilledHoleDiameterD 1EdgeDistanceW Min.ThreadEngagement LengthL Min.
AB
2-56.078-.081.074-.077.197.0779.046.172
4-40.102-.105.096-.099.220.1006.065.224
6-32.125-.128.119-.122.242.1238.081.276
8-32.152-.155.145-.148.272.1498.081.328
10-24.174-.177.165-.168.315.1710.108.380
10-32.179-.182.171-.174.315.1758.081.380
12-24.200-.203.191-.194.359.1970.108.432
1/4-20.232-.235.221-.224.415.2273.130.500
All dimensions in millimeters
ThreadCast HoleDiameter 1CastBossDiameterC Min.DrilledHoleDiameterD 1EdgeDistanceW Min.ThreadEngagement LengthL Min.
AB
M2 x 0.41.83-1.911.73-1.813.321.821.004.00
M2.5 x 0.452.31-2.392.20-2.284.152.291.205.00
M3 x 0.52.82-2.902.68-2.764.982.771.306.00
M3.5 x 0.63.23-3.313.13-3.215.813.231.607.00
M4 x 0.73.74-3.823.56-3.646.643.681.808.00
M5 x 0.84.72-4.804.50-4.588.304.642.1010.00
M6 x 15.66-5.745.40-5.489.965.542.6012.00
  1. Hole diameters provide approximately 65% to 75% of thread engagement.
  2. Dimensions are suggestions only. PENCOM strongly recommends testing in the application to determine actual working dimensions.

TA Thread-rolling screws are available in a variety of head styles, drives, lengths, materials and finishes. Custom configurations such as SEMS washers, dog points and partially threaded shanks for “captive” applications are possible as well. Speak with a PENCOM Account Manager to learn more.

Filed under: Technical Bulletins