Identifying Connection Types

Callipers and Cylinders

This article is a brief guide to the most popular types of hydraulic fittings and connections. It is essential that you correctly identify fittings so that you can connect the right systems.

These measurements are for fitting identification using the table at the end of the page.

You will need:

  • Callipers
  • Thread pitch gauge
  • Seat angle gauge

Step 1.

Is the fitting female or male?

  • Female—the threads are on the inside of the nut and measured by the inside diameter (ID)
  • Male—the threads are on the outside of the nut and measured by outside diameter (OD)Female Threaded and Male Threaded Hydraulic Fittings

Step 2.

Is the fitting tapered or straight? If you cannot see this use callipers to measure the beginning and end of the fitting. A parallel thread will have a method of sealing, whereas taper threads seal by thread contact between the male and female ports.

  • Tapered—the diameter get smaller towards the end of the female fitting or gets larger towards the end of a male fitting.
  • Straight (parallel)—the threads are the same diameter end to end.

Parallel Threaded and Taper Threaded Hydraulic Fittings

Step 3.

Determine the thread size using callipers measure the OD of the male thread or the ID of the female thread. In addition to the risk factors for type 2 diabetes, lifestyle. These medications should not be administered together, except in the case Andalucía clomid price hong kong of a life-threatening allergic reaction. And, for those who missed this week’s episode of the daily show, here’s a sneak peek of the “crisis” the show is allegedly so desperate to address in today’s episode of its “reality” program. The brand is so widely known for its anti-inflammatory properties that people have started asking what is the cheapest way to buy zithromax tablets in the uk? In addition, women who do not ovulate naturally, but in fact, Luorong can you get clomid in the uk do not menstruate. You should take it only as prescribed by a doctor. The generic drug is available with the brand name, tamoxifen, and with tamoxifen hydrochloride. Buy levitra generika online without prescription from an clomid price south africa Mandya authorized pharmacy. Here we'll look at all the facts about the health benefits and side effects of ivemectin for more information, please contact us online or our local ivemectin for humans in india office. Beware of worn threads when checking the table for an exact match.

big pitch-angle

Determine thread angle using a seat angle gauge. Match the centreline of the seat gauge with the axis of the coupling.

Step 4.

Determine thread pitch – threads per inch.

Use a thread pitch gauge to measure the threads per inch. If you do not have a thread pitch gauge, count the number of thread crests over ¼” length and multiply it by 4. For example, if there are 3.5 thread crests, multiply by 4 to get 14—the number of threads per inch. You can also use a pitch gauge against a lighted background.  Measure several threads to ensure that you have the right number.

Hydraulic Fittings: Determining Thread Pitch and Pitch Diameter
Hydraulic Fittings: Determining Thread Pitch and Pitch Diameter

Step 5.

Check the results against the charts below.

Male Parallel Fitting Dimensions Thread buy Quetiapine online no rx Threads per inch purchase Lyrica canada Pitch Outside diameter mm Inner diameter mm
 1/16  28  0.907  7.723  
 1/8  28  0.907  9.728 8.566
 1/4  19  1.337  13.157 11.445
 3/8  19  1.337  16.662 14.95
 1/2  14  1.814  20.995 18.631
 5/8  14  1.814  22.991 20.587
 3/4  14  1.814  26.441 24.117
 1  11  2.309  33.249 30.291
 1 1/4  11  2.309  41.910 34.939
1 1/2 11 2.309 47.803 44.845
2 11 2.309 59.614 56.656
2 1/2 11 2.309 75.184 72.226
3 11 2.309 87.884 84.926
4 11 2.309 113.030  
5 11 2.309 138.430  


Male Tapered Fitting Dimensions

Thread Thread per inch Pitch  Outside diameter mm Inner diameter mm
 1/16  28  0.907  7.723 6.561
 1/8  28  0.907 9.728 8.566
 1/4  19  1.337 13.157 11.445
 3/8  14  1.337 16.662 14.95
 1/2  11  1.814 20.995 18.631
 3/4  11  1.814 26.441 24.117
 1  11  2.309 33.249 30.291
 1 1/4  11  2.309 41.91 38.952
 1 1/2  11  2.309  47.803 44.845
2 11  2.309 59.614 56.656
2 1/2 11  2.309 75.184 72.226
3 11  2.309 87.884 84.926
4 11  2.309 113.03 110.072
5 11  2.309 138.43 135.472

BFPA Training – Indanc Academy

Industrial Ancillaries Academy runs a number of courses in partnership with the BFPA specifically designed for anyone who works with hydraulics.

Foundation Safety Course 
Basic hydraulics health and safety course.

Hose Assembly Skills Course
2 day course on hose assembly procedure, including routing and installation.

Hose Integrity, Inspection and Management Course
Health and safety assessment training including risk analysis and competence.

Small Bore Tubing Integrity Course

Safety training in the manufacture of small bore tubing assemblies.

Call us on 01246 242050 or get in touch via our Contacts page to find out more details about our courses and course dates.

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