Capstan Bollard Grips
TestResources’ Capstan Bollard grip designs are simple and cost effective gripping solutions that reduce jaw breaks and sample slippage that are common in direct clamp designs. Capstan Bollard grips are all engineered to perform high strength tensile tests where the test samples are long compared to their cross-sectional area, such as wire, rope and strapping. We offer a wide selection of options in both standard and custom engineered solutions. All of our capstan bollard grips will fit any brand of test machine through the use of an adapter.
| Family | Max Force | Max Thickness | Style | Clamp Type |
|---|---|---|---|---|
| G13 | 0.2 to 5 kN (45 to 1125 lbf) | 3 mm (0.12 in) | Horn Capstan | Pneumatic |
| G9 | 2.5 kN (550 lbf) | 6 mm (0.24 in) | Capstan Snubbing | Mechanical |
| G9P | 2.5 kN (550 lbf) | 6 mm (0.24 in) | Capstan Snubbing | Pneumatic |
| G76 | 1 to 20 kN (225 to 4500 lbf) | 9 mm (0.37 in) | Capstan Snubbing | Mechanical |
| G76P | 1 to 20 kN (225 to 4500 lbf) | 9 mm (0.37 in) | Capstan Snubbing | Pneumatic |
| G255SK | 10 kN (2250 lbf) | 4 mm (0.16 in) | Capstan Snubbing | Mechanical |
| G185P | 20 to 50 kN (4500 to 11250 lbf) | 20 mm (0.8 in) | Capstan Snubbing | Pneumatic |
| G170 | 50 or 100 kN (11 to 22 kip) | 20 mm (0.8 in) | Capstan Snubbing | Mechanical |
| G170H | 100 to 250 kN (22 to 55 kip) | 20 mm (0.8 in) | Capstan Snubbing | Hydraulic |
| G375 | 5 kN (1125 lbf) | 20 mm (0.8 in) | Bollard | Mechanical |
| G375P | 1.3 kN (290 lbf) | 20 mm (0.8 in) | Bollard | Pneumatic |
| G252 | 10 to 50 kN (2 to 11 kip) | 24.4 mm (0.9 in) | Bollard | Mechanical |
| G222 | 20 to 150 kN (5 to 33 kip) | 30 to 80 mm (1.2 to 3.1 in) | Bollard | Mechanical |
| G806 | 50 kN (11250 lbf) | 100 mm (4 in) | Bollard | Mechanical |
| G77 | 50 kN (11250 lbf) | 110 mm (4.3 in) | Bollard | Mechanical |
| G820 | 12 kN (2700 lbf) | 11 mm (0.44 in) | Bollard | Pneumatic |
| G172 | 50 kN (11250 lbf) | 20 to 60 mm (0.8 to 2.36 in) | Bollard | Mechanical |
| G172P | 3.5 kN (786 lbf) | 40 to 60 mm (1.57 to 2.36 in) | Bollard | Pneumatic |
Fits Any Brand Test Machine
Our grips and fixtures will fit any brand of test machine. We offer adapters that allow the grips and fixtures to be used on test machines from TestResources, Instron®, MTS®, Tinius Olsen® and every other brand of machine.
Capstan Bollard Grip Styles
Three proven designs styles with more than 20 standard variations! Hydraulic and pneumatic versions produce consistent clamp loads and mechanical versions tend to be more affordable.
Horn Style Capstan Grips for Round Samples
Horn style pneumatic capstan grips are ideal for round samples, narrow ribbons and other light force applications. The curved half capstan design evenly distributes gripping force through friction which eliminates the risk of premature sample failure in the grip section. This style capstan grip features a special smooth horn for easy sample loading and pneumatic clamping for more consistent clamp loads, more consistent results and reduced operator fatigue after multiple tests. As with all pneumatic clamping, the pneumatic clamping of the horn style capstan grip is especially valuable in high volume test applications involving repetitive opening and closing actions such as supporting or being a part of a production line. This reduces the risk of repetitive strain injuries occurring on the job.
Snubbing Style Capstan Grips for Round Samples
Snubbing style capstan grips are ideals for round sample or narrow ribbons. Snubbing style capstan grips use a spool to wrap the specimen around and a clamped snubber to secure the specimen free end. The majority of the tension force is carried by the spool which reduces specimen slippage and failure in the grip section. These are available with hydraulic, pneumatic or mechanical clamping.
Bollard Style Grips for Flat Samples
Bollard style grips are an ideal solution for high strength textile materials that are not typically gripped successfully with side action grips. These grips are designed to place the test sample on the test machine centerline to ensure accurate test data. The majority of the tension force is carried by the spool which reduces specimen slippage and failure in the grip section. These are available with pneumatic or mechanical clamping.
Can be Configured to your Specific Application
We can configure grips and jaws to fit any sample geometry including round samples like wire and fasteners. Our experienced engineers will work with you to ensure your test system is configured to meet your specific application requirements.
Horn style and snubbing style capstan grips are ideal for round and triangular shaped samples such as:
- Wire
- Rope
- Thread
- Fishing line
- Sutures
- Dental floss
- Cable
- 3D printing bulk filament material
- And more...
Bollard Style Capstan grips are ideal for flat shaped samples such as:
- Webbing
- Strapping
- Slings
- Seatbelts
- And more...
Common Industry Standards:
| Standard | Material | Grip Model |
| ASTM A931 | Steel Wire Rope | GA931 |
| ASTM D2256 | Yarn | GD2256-13 |
| ASTM D3217 | Textile Fiber & Yarn | GD3217 |
| ASTM D3950 | Non metallic strapping | GD3950-806 |
| ASTM D6775 | Textile Webbing, Tape and Braided Material | GD6775-221 |
| ASTM D7269 | Aramid Cords | GD7269-13 |
| ASTM D8054 | Para-Aramid Flat Yarns | GD8054 |
| ASTM E8 | Metal Wire | GE8-76 |
Compatible with Different Testing Environments
Grips can be constructed of different materials and surface treatments such as stainless steel, titanium and nickel coating. Nickel coated versions can be used inside hot and cold temperature chambers. The nickel coating helps protect the grips from corrosion caused by condensation from the freeze/thaw cycles inside the chamber. It also protects the grips from moisture inside humidity chambers which helps protect the grips from rusting over time. Nickel coated grips or grips made from corrosion resistant materials such as 316 stainless steel or titanium have an important benefit to people whose labs are in humid climates or near coastal areas of the ocean. Stainless steel versions are used in harsh environments such as saline bathes. The stainless steel material protects the grips from corrosion.
Standard and Custom Engineered Solutions
We offer many standard products as well as custom solutions. However, our modular platform enables us to adjust designs for any application requirement including customized bodies for larger or wide test samples. We understand that every sample can be unique. With this in mind, we offer custom engineered grips to match your specimen with any test force. Through the use of some of our standard elements, we can configure a wide variety of unique solutions without paying a “custom price” or waiting months to receive your order. Our modular platform approach satisfies virtually any application requirement.
Wide Range of Supporting Options
We offer a wide range of supporting options for our capstan bollard grips. Some of these options include:
Interchangeable Jaws or Jaw Faces - Various jaws are available and we can also easily custom engineer our jaws to fit unique test samples. Nickel coating comes standard on most capstan grip jaws and offers superior corrosion resistance.
Variety of Jaw Surfaces - We offer a wide variety of jaw surfaces for various sample types including:
- Smooth
- Rubber-coated
- Diamond grit coated
- Serrated
- Custom engineered jaw surfaces
Related Products
There are so many tensile fixtures to choose from it can be overwhelming and you certainly don’t want to make the mistake of selecting the wrong one. Give us a call today to speak to one of our experienced engineers that will work with you to find the exact solution based on your test requirements.
