Oilfield Torque Conversion Guide for Power Tongs

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Static Engineering Conversion Reference

Convert torque between foot-pounds, newton-metres, kilonewton-metres, pound-inches and kilogram-force metres using the formulas and lookup tables below.

The page covers everyday engineering values and high-torque oilfield ranges used when comparing tubing, casing and drill pipe power tongs. Values are rounded for practical lookup; use the full conversion factor when a controlled engineering calculation requires more precision.

1 lbf·ft equals1.35582 N·m

1 N·m equals0.737562 lbf·ft

1 kN·m equals737.562 lbf·ft

1 kgf·m equals9.80665 N·m

Terminology: Searchers commonly write “ft-lb,” “lb-ft” or “foot pounds.” For torque, the technically clearer notation is pound-force foot, written lbf·ft. This page retains common search wording while distinguishing torque from energy.

Torque Conversion Formulas

ft-lb to N·mN·m = ft-lb × 1.355817948

N·m to ft-lbft-lb = N·m × 0.737562149

ft-lb to kN·mkN·m = ft-lb × 0.001355817948

kN·m to ft-lbft-lb = kN·m × 737.562149

lb-in to N·mN·m = lb-in × 0.112984829

kgf·m to N·mN·m = kgf·m × 9.80665

The NIST conversion factor for pound-force foot to newton metre is 1.355818 when rounded to the digits published in its SI conversion tables. The extra digits shown above keep the lookup tables internally consistent.

ft-lb to N·m Conversion Chart

This table covers common engineering values from 1 to 1,000 ft-lb. For larger power tong and tubular connection values, use the high-torque table in the next section.

Torque, ft-lb	Torque, N·m	Torque, kN·m	Torque, kgf·m
1	1.36	0.00136	0.14
5	6.78	0.00678	0.69
10	13.56	0.01356	1.38
15	20.34	0.02034	2.07
20	27.12	0.02712	2.77
25	33.90	0.03390	3.46
30	40.67	0.04067	4.15
40	54.23	0.05423	5.53
50	67.79	0.06779	6.91
60	81.35	0.08135	8.30
75	101.69	0.10169	10.37
80	108.47	0.10847	11.06
100	135.58	0.13558	13.83
125	169.48	0.16948	17.28
150	203.37	0.20337	20.74
200	271.16	0.27116	27.65
250	338.95	0.33895	34.56
300	406.75	0.40675	41.48
400	542.33	0.54233	55.30
500	677.91	0.67791	69.13
600	813.49	0.81349	82.95
750	1,016.86	1.01686	103.69
1,000	1,355.82	1.35582	138.25

Common examples: 20 ft-lb is approximately 27.12 N·m; 100 ft-lb is approximately 135.58 N·m; 500 ft-lb is approximately 677.91 N·m; and 1,000 ft-lb is approximately 1.356 kN·m.

High-Torque Oilfield Conversion Chart

The following range is more relevant to power tongs, rotary-shouldered connections, casing-running equipment and heavy tubular handling systems.

Torque, ft-lb	Torque, N·m	Torque, kN·m	Torque, kgf·m
1,000	1,356	1.36	138
2,000	2,712	2.71	277
2,500	3,390	3.39	346
3,000	4,067	4.07	415
5,000	6,779	6.78	691
7,500	10,169	10.17	1,037
10,000	13,558	13.56	1,383
12,500	16,948	16.95	1,728
15,000	20,337	20.34	2,074
20,000	27,116	27.12	2,765
25,000	33,895	33.90	3,456
30,000	40,675	40.67	4,148
40,000	54,233	54.23	5,530
50,000	67,791	67.79	6,913
60,000	81,349	81.35	8,295
75,000	101,686	101.69	10,369
80,000	108,465	108.47	11,060
100,000	135,582	135.58	13,825
125,000	169,477	169.48	17,282
150,000	203,373	203.37	20,738

Conversion is not a torque recommendation. A converted number only expresses the same torque in another unit. It does not establish the correct makeup torque for drill pipe, casing, tubing or a premium connection.

kN·m to ft-lb Conversion Chart

Power tong specifications are frequently published in kN·m, while drilling contractors and field programs may use ft-lb. This table allows direct comparison of common oilfield equipment ratings.

Torque, kN·m	Torque, N·m	Torque, ft-lb	Torque, kgf·m
1	1,000	738	102
2	2,000	1,475	204
3	3,000	2,213	306
5	5,000	3,688	510
6	6,000	4,425	612
10	10,000	7,376	1,020
13	13,000	9,588	1,326
15	15,000	11,063	1,530
20	20,000	14,751	2,039
25	25,000	18,439	2,549
30	30,000	22,127	3,059
35	35,000	25,815	3,569
40	40,000	29,502	4,079
50	50,000	36,878	5,099
60	60,000	44,254	6,118
70	70,000	51,629	7,138
75	75,000	55,317	7,648
80	80,000	59,005	8,158
85	85,000	62,693	8,668
90	90,000	66,381	9,177
100	100,000	73,756	10,197
110	110,000	81,132	11,217
125	125,000	92,195	12,746
150	150,000	110,634	15,296
175	175,000	129,073	17,845
200	200,000	147,512	20,394

Oilfield examples: 13 kN·m is approximately 9,588 ft-lb; 30 kN·m is approximately 22,127 ft-lb; 100 kN·m is approximately 73,756 ft-lb; and 125 kN·m is approximately 92,195 ft-lb.

N·m to ft-lb Conversion Chart

Torque, N·m	Torque, ft-lb	Torque, lb-in	Torque, kgf·m
1	0.74	8.85	0.10
5	3.69	44.25	0.51
10	7.38	88.51	1.02
20	14.75	177.01	2.04
25	18.44	221.27	2.55
50	36.88	442.54	5.10
75	55.32	663.81	7.65
100	73.76	885.07	10.20
150	110.63	1,327.61	15.30
200	147.51	1,770.15	20.39
250	184.39	2,212.69	25.49
300	221.27	2,655.22	30.59
400	295.02	3,540.30	40.79
500	368.78	4,425.37	50.99
600	442.54	5,310.45	61.18
750	553.17	6,638.06	76.48
1,000	737.56	8,850.75	101.97
1,500	1,106.34	13,276.12	152.96
2,000	1,475.12	17,701.49	203.94

lb-in to N·m and ft-lb Conversion Chart

Pound-inches are common for smaller fasteners, instrument components and lower-torque tools. Do not confuse lb-in with lb-ft: one lb-ft equals 12 lb-in.

Torque, lb-in	Torque, N·m	Torque, ft-lb	Torque, kgf·cm
1	0.113	0.083	1.15
5	0.565	0.417	5.76
10	1.130	0.833	11.52
20	2.260	1.667	23.04
25	2.825	2.083	28.80
50	5.649	4.167	57.61
75	8.474	6.250	86.41
100	11.298	8.333	115.21
120	13.558	10.000	138.25
150	16.948	12.500	172.82
200	22.597	16.667	230.42
250	28.246	20.833	288.03
500	56.492	41.667	576.06
750	84.739	62.500	864.09
1,000	112.985	83.333	1,152.12
2,000	225.970	166.667	2,304.25
5,000	564.924	416.667	5,760.62

kgf·m to N·m, kN·m and ft-lb Chart

Some older equipment manuals and regional specifications use kilogram-force metre. It is a force-based torque unit and should not be shortened to “kg·m,” which can be confused with mass multiplied by length.

Torque, kgf·m	Torque, N·m	Torque, kN·m	Torque, ft-lb
1	9.81	0.010	7.23
2	19.61	0.020	14.47
5	49.03	0.049	36.17
10	98.07	0.098	72.33
20	196.13	0.196	144.66
25	245.17	0.245	180.83
50	490.33	0.490	361.65
100	980.66	0.981	723.30
200	1,961.33	1.961	1,446.60
500	4,903.32	4.903	3,616.51
1,000	9,806.65	9.807	7,233.01
2,000	19,613.30	19.613	14,466.03
5,000	49,033.25	49.033	36,165.07
10,000	98,066.50	98.067	72,330.14

How Torque Units Appear in Oilfield Power Tong Specifications

Torque conversion becomes commercially useful when a purchaser receives a connection requirement in ft-lb but a power tong datasheet is expressed in kN·m—or the reverse. Compare the equipment rating with the required makeup and breakout torque under the model-specific hydraulic conditions.

Tubing Power Tong

3–13 kN·m Range

Goldenman’s current XYQ tubing power tong range lists low-gear rated torque from 3 to 13 kN·m, equivalent to approximately 2,213 to 9,588 ft-lb.

View Hydraulic Tubing Power Tongs

Drill Pipe Power Tong

100 kN·m Example

The ZQ203/100 drill pipe power tong manual lists a maximum low-speed torque of 100 kN·m at the specified hydraulic condition, equivalent to approximately 73,756 ft-lb.

Review Drill Pipe Power Tong Selection

High-Torque Drill Pipe Tong

125 kN·m Example

A 125 kN·m equipment rating converts to approximately 92,195 ft-lb. Final selection must still confirm the tool joint OD, connection torque, breakout requirement, jaws, dies and hydraulic supply.

View Goldenman Hydraulic Power Tongs

High gear and low gear are not interchangeable ratings. A power tong may provide high rotational speed with lower torque for spinning, and low speed with higher torque for final makeup or breakout. Compare the required operation with the correct gear rating.

How to Use Torque When Selecting a Power Tong

Torque is only one selection input. A complete match should consider the tubular, connection, gripping system, hydraulic supply and rig-floor arrangement together.

Tubing

Tubing Power Tong

Confirm tubing OD, coupling OD, connection type, target makeup torque, expected breakout torque, surface sensitivity and whether a matched hydraulic backup tong is required.

Casing

Casing Power Tong

Confirm casing OD, coupling OD, weight, grade, connection, torque-turn requirement, jaw coverage, backup arrangement and handling clearance.

View TQ Casing Power Tongs

Drill Pipe

Drill Pipe Power Tong

Confirm tool joint OD, connection, grade, approved makeup torque, expected breakout torque, high- and low-gear ratings, gripping profile and anti-crushing control.

1. Compare the Required Torque with the Correct Equipment Rating

Use the connection manufacturer’s current data to identify target makeup torque and any minimum, optimum or maximum limits. For breakout, account for the field procedure and expected service condition rather than assuming it equals makeup torque.

2. Confirm the Hydraulic Power Unit

Rated tong torque is achieved only under the model-specific hydraulic pressure and flow conditions. Check pressure, flow, return-line requirements, cooling, motor power and simultaneous auxiliary loads. Goldenman supplies air-cooled and water-cooled hydraulic power units for rig-floor equipment.

3. Confirm Jaws, Dies and Gripping Diameter

The tong must transfer torque without slipping or creating unacceptable tubular damage. Match the jaw assembly and die radius to the pipe body, coupling or tool joint actually being gripped. Goldenman can match replacement power tong jaws, dies and gripping inserts by model, part number, dimensions, drawing or sample.

4. Confirm Torque Measurement and Calibration

A converted torque target is only useful when the measurement system is correctly installed and calibrated. Confirm the load cell, torque arm, gauge or electronic torque-turn system, backup-line geometry, zero setting and calibration record.

Hydraulic pressure is not a universal torque unit. Two power tong models operating at the same MPa or psi can produce different torque because motor displacement, gearing, mechanical efficiency and tong geometry differ. Use only the pressure-to-torque chart for the exact tong model and gear.

Torque, Work and Energy: Why N·m Can Be Confusing

Torque and energy can both be dimensionally expressed using newton metres, but they describe different physical quantities. Torque is a rotational moment and should be written N·m. Energy is written joule, J. Do not convert a torque specification into joules or treat a torque value as energy merely because the dimensions appear similar.

Common Torque Conversion and Selection Mistakes

Mistake	Why It Causes a Problem	Correct Practice
Using lb-in as though it were lb-ft	Creates a 12-times torque error	Check whether the source unit is pound-inch or pound-foot.
Treating 100 N·m as 100 ft-lb	100 N·m is only about 73.76 ft-lb	Apply the conversion factor before comparing ratings.
Assuming a converted result is a recommended makeup torque	Conversion does not define the correct connection procedure	Obtain the approved connection torque from the manufacturer.
Comparing required torque with high-speed torque only	High gear normally has lower torque than low gear	Compare final makeup and breakout requirements with low-gear capacity.
Setting hydraulic pressure from a generic formula	Pressure-to-torque relationships are model-specific	Use the exact tong’s calibrated pressure-to-torque chart.
Ignoring jaw and die compatibility	Rated torque may not transfer safely to the tubular	Match gripping diameter, radius, tooth pattern and tubular material.
Using excessive rounding for controlled work	High values can accumulate meaningful conversion error	Retain sufficient significant digits in engineering and calibration records.

Information Required for Power Tong Selection

Include these details in the RFQ:

Tubular type: tubing, casing or drill pipe
Pipe body OD
Coupling or tool joint OD
Connection type
Approved makeup torque
Expected breakout torque
Torque unit used in the source document
High-speed requirement
Master tong gripping range
Backup tong gripping range
Required jaws and dies
Surface-damage limitation
Available hydraulic pressure
Available hydraulic flow
Voltage and frequency for HPU
Open-head or closed-head preference
Suspension and rig-floor arrangement
Torque gauge or torque-turn monitoring
Required certification and inspection
Destination and delivery schedule

Frequently Asked Questions

How do I convert ft-lb to N·m?

Multiply the ft-lb value by 1.355817948. For example, 100 ft-lb is approximately 135.58 N·m.

How do I convert N·m to ft-lb?

Multiply the N·m value by 0.737562149. For example, 100 N·m is approximately 73.76 ft-lb.

How many ft-lb are in 1 kN·m?

One kilonewton metre equals approximately 737.56 ft-lb.

How many ft-lb is 100 kN·m?

One hundred kN·m equals approximately 73,756 ft-lb.

How many kN·m is 50,000 ft-lb?

Fifty thousand ft-lb equals approximately 67.79 kN·m.

What is the difference between lb-in and lb-ft?

One lb-ft equals 12 lb-in. Confusing the two units creates a twelve-times error.

Can I use this chart to set drill pipe makeup torque?

The chart can convert an approved torque value between units, but it cannot determine the correct torque for a connection. Use the current connection manufacturer’s data and the applicable drilling procedure.

Can hydraulic pressure be converted directly into power tong torque?

Only through the pressure-to-torque relationship for the exact power tong model, gear and calibration condition. A universal MPa-to-kN·m or psi-to-ft-lb conversion does not exist.

Should power tong capacity be higher than the target makeup torque?

The equipment should provide a suitable operating margin without exceeding the tubular or connection limits. The required margin should be established by the operating procedure, equipment manufacturer and connection requirements.

Why does a power tong have different high- and low-speed torque ratings?

High gear is used for faster spinning at lower torque, while low gear provides higher torque at lower speed for final makeup or breakout.

Match Your Torque Requirement to the Correct Power Tong

Send Goldenman the tubular type, pipe or tool joint OD, connection, approved makeup torque, expected breakout torque, hydraulic pressure, flow, backup tong requirement and gripping-surface limitations. Goldenman can compare tubing, casing and drill pipe power tong configurations and prepare an order-specific technical quotation.

Email: info@goldenman.com

Goldenman

Petroleum Equipment Supplier for more than twenty years.

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Oilfield Torque Conversion Guide for Power Tongs

Table of Contents

Torque Conversion Formulas

ft-lb to N·m Conversion Chart

High-Torque Oilfield Conversion Chart

kN·m to ft-lb Conversion Chart

N·m to ft-lb Conversion Chart

lb-in to N·m and ft-lb Conversion Chart

kgf·m to N·m, kN·m and ft-lb Chart

How Torque Units Appear in Oilfield Power Tong Specifications

3–13 kN·m Range

100 kN·m Example

125 kN·m Example

How to Use Torque When Selecting a Power Tong

Tubing Power Tong

Casing Power Tong

Drill Pipe Power Tong

1. Compare the Required Torque with the Correct Equipment Rating

2. Confirm the Hydraulic Power Unit

3. Confirm Jaws, Dies and Gripping Diameter

4. Confirm Torque Measurement and Calibration

Torque, Work and Energy: Why N·m Can Be Confusing

Common Torque Conversion and Selection Mistakes

Information Required for Power Tong Selection

Frequently Asked Questions

How do I convert ft-lb to N·m?

How do I convert N·m to ft-lb?

How many ft-lb are in 1 kN·m?

How many ft-lb is 100 kN·m?

How many kN·m is 50,000 ft-lb?

What is the difference between lb-in and lb-ft?

Can I use this chart to set drill pipe makeup torque?

Can hydraulic pressure be converted directly into power tong torque?

Should power tong capacity be higher than the target makeup torque?

Why does a power tong have different high- and low-speed torque ratings?

Match Your Torque Requirement to the Correct Power Tong

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