In the field of plumbing, it is advisable to know the appropriate dimensions for pipe fittings and accessories. Indeed, choosing the wrong size can lead to leaks, a decrease in system performance, or even material damage. But how do you know if a fitting is 12x17 or 15x21? In this article, we will examine the different methods for determining the exact size of your plumbing fittings.
Understanding the dimensions of plumbing fittings
Before you can determine if a fitting is size 12x17 or 15x21, it is important to understand how these measurements are expressed. The dimensions of plumbing fittings are generally represented by two numbers separated by an "x". The first number corresponds to the outer diameter (OD) of the tube, while the second number indicates the thread pitch, i.e., the distance between the threads of the threaded part of the fitting in millimeters.
For example:
- A 12x17 fitting will have an outer diameter of 12 mm and a thread pitch of 17 mm.
- A 15x21 fitting will have an outer diameter of 15 mm and a thread pitch of 21 mm.
So, to determine if a fitting is size 12x17 or 15x21, you need to measure these two aspects of the fitting, namely the outer diameter and the thread pitch.
Using a caliper to measure dimensions
The most accurate way to determine the size of a plumbing fitting is to use a caliper. This measuring tool allows you to accurately evaluate the outer diameter and thread pitch of the fittings, ensuring that you choose the right size for your installation. Here's how to use a caliper to measure the dimensions of a fitting:
- Open the caliper by sliding its movable part until it can be placed around the fitting to be measured.
- Place the caliper around the outer diameter of the fitting, taking care to position its fixed part against the outer edge of the fitting.
- Slide the movable part of the caliper until it is firmly adjusted against the other side of the outer diameter of the fitting.
- Read the measurement displayed on the caliper and note the first number (outer diameter).
- To measure the thread pitch, place the caliper on the threaded part of the fitting and measure the distance between the crests of two consecutive threads.
- Note the second number (thread pitch).
Once these measurements are taken, you can compare the results to the standard dimensions of the 12x17 and 15x21 fittings to determine the right size for your plumbing project.
Checking the markings on fittings and pipes
In some cases, the dimensions of the fittings may be directly indicated on their surfaces. This marking can take the form of a raised marking or a label attached to the fitting. If this is the case, you can simply read this information to know the exact dimension of the fitting.
Similarly, if you have already purchased tubes intended to be connected by the fittings in question, it is possible that these fittings also display their dimensions on their surface. You can thus verify that the size of the fittings corresponds to that of the tubes to ensure a successful and problem-free installation.
Consideration of standards and materials
When choosing fittings for your plumbing system, it is essential to consider the applicable standards as well as the materials of manufacture. Fittings can be made from various materials such as copper, stainless steel, plastic, or brass. Each material has its own characteristics and advantages, so it is important to choose a fitting suitable for your project and compliant with local regulations regarding plumbing.
Measuring the sanitary elements to be connected
Finally, another way to determine the size of a fitting is to measure the sanitary equipment to which they will be connected. Indeed, in some cases, the dimensions of the fittings may be different from those of the pipes and other elements of the plumbing system. By accurately measuring these equipment (for example, the inner and outer diameter of a shower mixer tap or the distance between the threads on a sink trap), you can more easily select the right fitting to achieve a watertight and efficient connection.
In summary, to determine if a plumbing fitting is of size 12x17 or 15x21, it is necessary to accurately measure its outer diameter and thread pitch using a caliper, to check the possible inscriptions on the fitting or the tubes concerned, and to take into account the legal requirements relating to standards and materials.
