Torque Limiters

PT Tech’s continuously engaged friction torque limiters require no resetting.  Color coded spring cups provide visual identification of the torque setting and are torque tamperproof.  Our torque limiters offer high torque accuracy for the lifetime of the clutch, providing high levels of uptime and safety for your equipment.

FMD Series

PT Tech’s FMD series is a friction-type multiple disc torque limiter for high horsepower, high energy and/or limited space applications. They are designed to operate on the high speed side of a drive system. 

Torque Limiter FMD 28

Technical Specs

Max Torque 7,640 lb-ft 10,352 Nm
Max Speed 3,450 rpm
Outside Diameter 16.50 in 419.1 mm
Torque Limiter Length 6.67 in 169.4 mm
Outside Hub Length 5.65 in 143.5 mm
Max Bore 4.29 in 109.0 mm

Torque Limiter FMD 36

Technical Specs

Max Torque 15,168 lb-ft 20,544 Nm
Max Speed 2,500 rpm
Outside Diameter 20.13 in 511.3 mm
Torque Limiter Length 7.16 in 181.9 mm
Outside Hub Length 6.00 in 152.4 mm
Max Bore 5.375 in 136.5 mm

Torque Limiter FMD 44

Technical Specs

Max Torque 25,552 lb-ft 34,752 Nm
Max Speed 2,050 rpm
Outside Diameter 23.75 in 603.3 mm
Torque Limiter Length 7.16 in 181.9 mm
Outside Hub Length 6.00 in 152.4 mm
Max Bore 7.375 in 200 mm

UJT Series

PT Tech’s UJT-500 Series is a maintenance-free continuously engaged friction type torque limiter.

The torque setting is pre-set at the factory. The tamper resistant torque setting can only be changed by installing a different complement of spring cup bolts thus preventing equipment damage due to unauthorized adjustment. 

The spring cup bolts are pretested and pre-shimmed to maintain a consistent and predictable force on the friction material. They eliminate the need to adjust the torque limiter torque setting at installation and throughout its wearlife. The spring cup bolts are color-coded according to their strength. The torque is easy to verify by counting the quantity and color of spring bolt assemblies. 

The standard output is machined  to accept a Spicer industrial driveshaft. The UJT-500 Series is available with optional input and output configurations. The UJT-500 Series clutches are continuously engaged. They are not subject to nuisance  trip-outs like releasable torque limiters (shear pins, ball detent, pressurized slip devices, etc.). The UJT will act like a torsional shock absorber and does not limit drive engine performance because the torque setting is above the engine or electric motor’s peak torque. 

Torque Limiter UJT 28

Technical Specs

Max Torque 2,292 lb-ft
Max Speed 3,000 rpm
Inertia – Complete Torque Limiter w/o Coupling 17.4 lb-ft2
Inertia – Torque Limiter Output only 2.4 lb-ft2
Weight 102 lbs
Torque Limited Double disc output

Torque Limiter UJT 228

Technical Specs

Max Torque 4,584 lb-ft
Max Speed 2,100 rpm
Inertia – Complete Torque Limiter w/o Coupling 19.4 lb-ft2
Inertia – Torque Limiter Output only 2.7 lb-ft2
Weight 115 lbs
Torque Limited Double disc output

Torque Limiter UJT 328

Technical Specs

Max Torque 6,876 lb-ft
Max Speed 2,100 rpm
Inertia – Complete Torque Limiter w/o Coupling 21.5 lb-ft2
Inertia – Torque Limiter Output only 3.2 lb-ft2
Weight 130 lbs
Torque Limited Triple disc output

Torque Limiter UJT 35

Technical Specs

Max Torque 3,024 lb-ft
Max Speed 2,100 rpm
Inertia – Complete Torque Limiter w/o Coupling 41.3 lb-ft2
Inertia – Torque Limiter Output only 6.0 lb-ft2
Weight 164 lbs
Torque Limited 6.0 lb-ft2

Torque Limiter UJT 235

Technical Specs

Max Torque 3,024 lb-ft
Max Speed 2,100 rpm
Inertia – Complete Torque Limiter w/o Coupling 41.3 lb-ft2
Inertia – Torque Limiter Output only 6.0 lb-ft2
Weight 164 lbs
Torque Limited 6.0 lb-ft2

Torque Limiter UJT 335

Technical Specs

Max Torque 9,072 lb-ft
Max Speed 1,800 rpm
Inertia – Complete Torque Limiter w/o Coupling 48 lb-ft2
Inertia – Torque Limiter Output only 7.7 lb-ft2
Weight 198 lbs
Torque Limited Triple disc output

SLQ Series

PT Tech’s SLQ series is a friction torque limiter designed for standard torque and energies.

This is an economical way to protect your expensive drive train from shockload damage, while allowing your equipment to continue to perform. No resetting is required after shockloads occur and torques are pre-set by your design staff. 

Torque Limiter SLQ 15

Technical Specs

Max Torque 438 lb-ft 594 Nm
Max Speed 3,600 rpm
Inertia Total 2.32 lb-ft2 0.0977 kg-m2
Inertia Output 0.16 lb-ft2 0.0067 kg-m2
Weight 27 lbs 12.3 kg

Torque Limiter SLQ 19

Technical Specs

Max Torque 950 lb-ft 1,288 Nm
Max Speed 3,000 rpm
Inertia Total 5.1 lb-ft2 0.2147 kg-m2
Inertia Output 0.43 lb-ft2 0.0181 kg-m2
Weight 45 lbs 20.5 kg

Torque Limiter SLQ 28

Technical Specs

Max Torque 2,096 lb-ft 2,842 Nm
Max Speed 2,500 rpm
Inertia Total 16.94 lb-ft2 0.7133 kg-m2
Inertia Output 1.75 lb-ft2 0.0737 kg-m2
Weight 84 lbs 38.2 kg

Torque Limiter SLQ 35

Technical Specs

Max Torque 3,828 lb-ft 5,192 Nm
Max Speed 2,000 rpm  
Inertia Total 40.32 lb-ft2 1.699 kg-m2
Inertia Output 6.81 lb-ft2 0.287 kg-m2
Weight 169 lbs 376.85 kg

SL Series

PT Tech’s SL series is a friction torque limiter designed for standard torque and energy requirements for mining applications.

This is an economical way to protect your expensive drive train from shockload damage, while allowing your equipment to continue to perform. No resetting is required after shockloads occur and torques are pre-set by your design staff. PT Tech has other model torque limiters for applications requiring greater torque capacity within the same diameter as the SL series.

Torque Limiter SL 19

Technical Specs

Max Torque 3,312 lb-ft 4,490 Nm
Max Speed 2,000 rpm
Inertia Total 6.32 lb-ft2 0.266 kg-m2
Inertia Output 0.785 lb-ft2 0.033 kg-m2
Weight 74 lbs 34 kg
Outside Diameter 10 in 254.0 nm

Torque Limiter SL 23

Technical Specs

Max Torque 5,724 lb-ft 7,761 Nm
Max Speed 2,000 rpm
Inertia Total 8.74 lb-ft2 0.368 kg-m2
Inertia Output 0.757 lb-ft2 0.032 kg-m2
Weight 80 lbs 36 kg
Outside Diameter 11.25 in 285.8 nm

Torque Limiter SL 28

Technical Specs

Max Torque 4,584 lb-ft 6,215 Nm
Max Speed 2,000 rpm
Inertia Total 15.9 lb-ft2 0.670 kg-m2
Inertia Output 1.99 lb-ft2 0.084 kg-m2
Weight 105 lbs 48 kg
Outside Diameter 13.125 in 333.4 nm

CMD Series

PT Tech’s CMD series are friction-type compact multiple disc torque limiters for levelers and flatteners on steel processing lines and other high torque, limited radial space applications.

They perform best on the slow speed side of a gearbox. The torque setting is set at the factory and does not require adjusting throughout its wear life. Wear life indicators are available on most designs. CMD units protect drive components from damaging torque overloads. Also, when a significant tension differential exists between the entry and exit rolls, the CMD’s will slip just enough to evenly distribute the load. 

Typically, CMD units are custom designed. There are two different design configurations, output shaft mounted and mid-spindle mounted. Examples of each configuration are shown. Maximum torque is affected by the available shaft engagement length (DIMENSION E), distance between centerlines of the output shafts, and the strength of available springs. 

Torque Limiter CMD 70

Technical Specs

Max Torque 490 lb·ft
Mounted Type Mid Spindle
A1 – Housing Diameter 2.75 in
A2 – Endplate Diameter 2.5 in
B – Housing Length 7.6 in
E – Shaft Engagement 6.96 in

Torque Limiter CMD 83

Technical Specs

Max Torque 600 lb·ft
Mounted Type Mid Spindle
A1 – Housing Diameter 3.25 in
A2 – Endplate Diameter 3.25 in
B – Housing Length 3.25 in
E – Shaft Engagement 3.25 in

Torque Limiter CMD 120

Technical Specs

Max Torque 550 lb·ft
Mounted Type Shaft
A1 – Housing Diameter 4.75 in
A2 – Endplate Diameter As Required
B – Housing Length 77.38 in
E – Shaft Engagement 6.38 in

Torque Limiter CMD 180

Technical Specs

Max Torque 3630 lb·ft
Mounted Type Shaft
A1 – Housing Diameter 7.12 in
A2 – Endplate Diameter As Required
B – Housing Length 9.72 in
E – Shaft Engagement 8.66 in