Heating pipes with ribs have been used for many decades and have not lost their relevance to this day. This equipment has its own design features that determine the use, therefore, they are rarely found in heating systems for private housing, but they are widely used for heating industrial premises. A photo of finned heating pipes will tell you what equipment we are talking about, after which we will consider the characteristics of this product in more detail.
The device of ribbed heating pipes
Pipe material in heating systems is used not only for the installation of heating pipelines, but also as radiators. To increase the efficiency of such a system, a section of a pipe of a larger diameter or a figured design (coil) cuts into the heating circuit, which increases the heat transfer area.
Later, another method began to be used — the finning of pipeline sections that act as radiators.
Thus, ribbed heating pipes are a pipe fragment of a certain length (carrier pipe) with transverse (less often — longitudinal) outer ribs located at a certain step. The finned element of the pipeline is equipped with inlet and outlet pipes for connection to the heating system. The branch pipes of such a radiator can be threaded, smooth (welded) or flanged.
One such product, ready for insertion into the heating circuit, is called a single-section register. If several single-section registers are mounted in rows located in one or two planes, a multi-section register will be obtained — a design that further increases the intensity of heating.
Depending on the material of execution, finning is performed in different ways, but the purpose of this operation is the same — to improve heat transfer between the heating pipeline and the environment by increasing the area of u200bu200btheir contact.
Types of finned tubes
Ribbed heating pipe elements are made of the following metals:
- cast iron (with additives of magnesium and cerium);
- stainless steel;
According to the structural structure, finned tubes are divided into:
- monometallic — solid products obtained by casting or turning from a workpiece;
- bimetallic — products assembled from pipes and ribs.
Monometallic products include cast iron finned tubes, which are manufactured by casting and must meet the requirements of GOST 1816–76, as well as copper and aluminum products, on which fins are formed by extrusion/rolling on a machine.
A bimetallic product is an internal carrier pipe made of stainless steel or brass, on which longitudinal or transverse copper or aluminum fins are located.
Finning of bimetallic pipes is carried out by the following methods:
- knurling — an aluminum or copper sleeve is put on the carrier pipe, on which ribs are squeezed out by rolling;
- spiral helical winding — a metal tape is pressed into the outer surface of the carrier pipe during spiral winding;
- spiral-helical high-frequency current — fastening the tape to the carrier pipe by welding the contact surfaces after they are heated by high-frequency current;
- longitudinal (axial) finning — connection of the tape with the carrier pipe by one of the types of welding.
In the manufacture of bimetallic tube registers for heat exchangers, the layout of materials can be as follows (carrier tube + fins):
- steel + aluminum;
- aluminum + aluminum;
- brass + aluminum
Specifications of Cast Iron Ribbed Tubes
Cast iron is a strong and durable metal with high thermal conductivity, therefore cast iron finned tubes are the most common in heating systems, which are characterized by the following parameters:
- inner diameter — from 32 to 70.0 mm;
- outer diameter (with ribs) — 175.0 mm;
- operating temperature of operation — up to 90 degrees. (short-term exposure up to 150 degrees),
- working pressure of the coolant in the system — 1.0 MPa;
- the length of individual elements is from 0.5 to 6.0 m.
The shape of the ribs can be round or rectangular. The rectangular format of finned heating tubes is more efficient due to the larger heat transfer surface area.
The use of pipe products of ribbed design made of cast iron
Due to their considerable weight and low level of aesthetics, cast iron finned radiators are mainly used for steam or water heating of production workshops, warehouses, livestock complexes and other objects of large areas. At the same time, the single use of such equipment is inefficient, and the elements are installed in sections of several radiators. Such heating registers made of ribbed tubes increase the intensity of space heating by several times, but at the same time require a large area for installation.
These devices are also suitable for heating housing, but they will require additional finishing in the form of decorative casings or false walls.
The high technical characteristics of cast iron determine the widespread use of cast iron finned tubes in economizers — gases and aggressive substances do not cause corrosion of the heat exchanger material when passing through them.
Installation of cast iron finned tubes
Due to the significant weight, ribbed heating registers place increased demands on the base. The bearing capacity of the walls (for wall-mounted radiators) and the strength of the brackets must be high, and the attachment of the fasteners to the base must be reliable. When the unit is installed on the floor, supports, standard or self-manufactured, must be welded at the bottom of it. If the floor is wooden flooring, then slots are made in it so that the radiator supports are located on the supporting floor slab.
Before installation, the finned radiator is cleaned of old paint and dirt, degreased, and then primed and painted. It is better to paint with an airbrush, because due to the configuration of the register, the painting area is large, and the fins are poorly accessible for brush work.
A solution of minium iron in drying oil is suitable as a primer, and a top coat is a heat-resistant paint (enamel) of a suitable color or a solution of aluminum powder. The painted register should not be under direct sunlight — the paint will flow.
Important! The finned radiator is installed so that from the floor to the longitudinal axis of its lower register is at least 20 cm, and from the side surface to the wall — at least 15 cm.
After the paint has dried, the painted radiator is installed in place, after which the device is additionally fixed to the wall in order to avoid accidental tipping over during mechanical action.
Connection to the heating circuit is made after the final installation of the unit, so that its displacement does not violate the tightness of the connections. Insertion is made depending on execution of branch pipes of the register — flange connection, on a carving or welding. When flanged, it is recommended to use paronite as a gasket material, cut to the dimensions of the flange mirrors (mirrors are cleaned of paint with fine sandpaper), or use standard gaskets, if they are provided in the package.
After the final installation of the unit, dot painting of areas damaged during installation is carried out.
Advantages and disadvantages of finned tubes
It is thanks to a number of advantages that cast iron finned heating pipes are used in heating systems to this day, we list these factors:
- body tightness;
- large heat transfer area;
- neutrality to any kind of corrosion;
- high thermal conductivity;
- durability (100 years is not the limit);
- affordable cost.
But there are also disadvantages:
- significant weight;
- low impact resistance;
- the difficulty of keeping clean (accumulation of dust in the fins, poor accessibility of the painting area);
In terms of its functionality, a cast iron ribbed heating radiator is the best option for completing a heating system for utility and utility rooms — the lack of aesthetics is compensated by durability, reliability and affordable cost, since the difficulty factor of painting in a utility room fades into the background.
The main essence of the article
- Ribbed cast iron heating registers are a material that has not become obsolete.
- The appropriateness of using ribbed heating pipes depends on the choice of the place of operation.
- The correct installation is one of the factors for the efficiency of the register.
- Knowing the characteristics of the radiator helps ensure longevity.