Pipe caps act as protective device and are designed to protect pipe ends of various shapes. The main purpose of using pipe caps is to waterproof the connections. They are also used to close the the ends of hydraulic or pneumatic pipes and tubes. They are used in the plumbing apparatus of domestic, commercial and industrial water supply lines, machinery and processing equipment etc. They are also fitted on water pump lines with the sole purpose of removing air blocks. Pipe caps are highly demanded as an important category of pipe fittings.
How to measure pipe caps?
As a large variety of materials are used for making pipe caps, the buyer should always take care of the material of the fitting before going for pipe caps. Some of the common materials used include:
- Nylon or polyamide
- Stainless steel
- Silicone rubber etc.
Certain factors to consider are as follows:
- Outer diameter
- Thread size
- Length and head type in shapes
Take the measurements of A, B and C as shown in the figure:
Common Shapes of pipe caps:
Pipe caps are available in various shapes. Having an intense knowledge
about the shape of pipe cap would be beneficial for the buyer. Some of
the common shapes of pipe caps are:
Features of pipe caps:
- “U” Shape Cap
- “I” Shape Cap
- Hex Cap etc.
There are several important specifications that the buyer should
consider before making bulk purchase of pipe caps. The important
specifications that needs to be considered are:
Types of pipe caps:
- NPT (National Pipe Thread ) size: This feature is
applicable for round shaped caps, wherein the object that has to be
protected has a male NPT thread.
- BSP (British Standard Pipe) size: This size option is
applicable only for round shaped caps, wherein the object to be
capped has a male BSP thread.
- Diameter: Diameter is an important dimension that is
applicable only for round caps and plugs. In case of fittings having
straight threads, the most important feature to be considered is the
major thread diameter. However, this dimension is not an important
consideration when cap, plug or object to be capped has a tapered
(NPT or BSP) thread.
- Shape: The dimension and shape of pipe caps are also very
important points to consider. Pipe caps of different shapes have
different features. Some features are:
- Round Caps: Popular features of round caps are:
flange, slotted head, knurled or faceted head, retaining head,
and tear tab. A flange is meant for easy removal or additional
protection of pipe or tube surfaces. Flanges also help to
prevent accidental pushing away of the plug through the opening.
Slotted caps can be easily installed or removed with the help of
a screwdriver. Knurled or faceted heads are usually designed for
threaded caps and plugs only. Knurls or facets offer hassle
free installation and removal. Pipe caps provided with a
tear-tab or strip are easy to remove.
- Square or Rectangular Cap: For square or rectangular
caps, length and width are the most important dimensions to
consider. For rectangular caps, the width is the smaller cross
sectional dimension, whereas for square caps, the length and
breadth are the same dimension.
Pipe caps come in many different types and the type vary according to
the application. However pipe caps also vary depending on their
construction features and it is very important for the buyer to know the
right type of pipe cap. Based on construction, pipe caps are of the
These caps are female threaded. The thread
can be either straight or tapered, also referred as NPT. Generally,
caps have a female thread and plugs have a male thread.
These caps have tapered sides, which offers
a close fit. Some of these fittings can be used either as a cap or a
plug. Tapered caps and plugs are multi-functional and go well with
male and female NPT threads, straight tubes and bars; and male
straight threads. These fittings have a tapered body to provide a
secure and firm friction fit while facilitating easy removal. The
tapered caps are designed to provide protection for all internal and
external, threaded and non-threaded fittings against damage, dirt or
moisture that can occur.
These caps are round in shape with a
slightly square end. This prevents pipes and tubes from rolling.
The points mentioned below will be a guide for the buyers: