The groove pipe fittings are gradually popularized in various types of building installation by using the groove pipe joint connection method, and its fast and reliable characteristics have been recognized by the installation industry colleagues, and the groove pipe fittings are also widely used in the construction of fire protection projects. However, different connection methods of rigid clamp, flexible clamp connection should pay attention to what problems, in the existing design, construction standards are not introduced much, China's existing product standards have been published in the clamp industry standards of many provisions, but also related to manufacturing standards, then, together with the following to understand the problems that should be paid attention to when installing trench pipe fittings!

In the actual construction, the problems encountered in the splint connection of trench pipe fittings and their solutions are put forward.

First, the rigid clamp is installed on the pipe road of DN250, according to the product manual provided by the manufacturer, and generally can achieve satisfactory results.

2. When connecting the DN300 pipeline with flexible clamps, please pay attention to the following installation details.

1, groove pipe quality:

The tolerance of outer diameter, wall thickness uniformity and roundness of pipe ends of groove fittings shall not exceed the national standard. When loading and unloading steel pipes, avoid nozzle deformation.

2, nozzle pressure groove before measurement and appearance inspection:

Before applying pressure to the nozzle, check whether the end face of the nozzle is perpendicular to the center line of the pipe, whether the nozzle rounding tolerance is out of standard, and whether the burrs around the nozzle have been removed and polished. For example, if the roundness of the nozzle exceeds the standard or is deformed, it must be removed.

3, groove pipe stamping processing:

For the long steel pipe press groove, in order to reduce the rotational fluctuation of the pipe when the pressure groove is low, it is necessary to set the bracket and install the ball bearing support point on the bracket. Strict groove depth, groove depth must meet the requirements of the product manufacturer manual. When operating, pay attention to the speed of the groove depth gradually reached, and the mold that exceeds the service life must be replaced in time. After pushing the can, remove the peeling galvanized thin skin from the nozzle and carry out anti-corrosion treatment. When handling, lifting, and loading the pipes of the completed tank, ensure that the nozzle groove is not deformed.

4, groove pipe appearance quality:

Because the large diameter steel strip is made of cast iron sand by ball mill, the manufacturing accuracy is affected by various factors. Therefore, the appearance of the sample inspection, inspection content includes the following items.

4.1 The diameter of the flexible belt that is crimped into a flat plate is too large or too small. Usually, when mastering the inner diameter of the two belts and the outer diameter of the steel pipe, the gap between the two belts is about 2mm, and the roundness must not exceed the standard. Otherwise, please fix it and wear it again.

4.2 The height and thickness of the flange inserted into the pressure groove of each clamp must meet the manufacturer's enterprise standards.

4.3 The radial deformation of each clamp itself shall not exceed the standard.

5, groove pipe clamp installation precautions:

5.1 Splint installation, especially the quality of flexible splint installation, in addition to the above points, according to the material of the pipe, shape size, pipe mouth deformation size, groove quality and splint itself quality, size of the excess size.

5.2 Pay attention when installing large-diameter flexible belts of dn300 or more.

5.2.1 Check the material and appearance of the rubber pad:

The rubber pad of each manufacturer is different according to the use of different media, manufacturing materials and formulas are different, and the installation unit should ask the production unit for the same product quality commitment letter and the physical and mechanical properties test report of the rubber pad. The appearance inspection has no damage and deformation, and the rubber sealing surface shall not have bubbles, impurities, cracks and uneven defects.

5.2.2 Installation of trench pipes:

a. Touch the grooves and holes with your hands or observe them with your eyes for 1 week. Do not leave burrs, damage, or cracks. Also, remove dirt around the nozzle.

b. After applying lubricant around the rubber pad, hook both ends of the steel pipe with your hand. At this point, ensure that the tension applied around the rubber seal is roughly consistent.

c. Set two slots and tighten the bolts symmetrically on both sides so that the gaps between the slots are basically equal. When the rubber pad is not sufficiently tight after tightening, push the tank tube with both hands, so that the whole tube is first in uniform contact with the packing, observe each piece of the tank tube into the tank, and tighten the bolt symmetrically and separately. When tightening, if there is a wrinkled protruding on the packing, replace the packing.

5.2.3 After the pipe flange is stuck in the groove, tighten the bolts on both sides symmetrically. The "card edge" refers to the protruding of about 2mm on the flange of the groove at the same height as the groove depth of the groove, and is flush with the recess that appears after pressing the nozzle groove. The flange of the finished belt may be too thick, the deformation is too large, and the plane may be too distorted. If it can be repaired on site, repair it, if it can't be repaired, throw it away and replace it with something else. Therefore, the on-site staff need to observe and check one by one, and the basic requirements can be reassembled to avoid rework.

5.2.4 When imported trough pipe fittings and domestic pipe fittings are used, it is necessary to understand in advance what standards the products used by the manufacturers are in accordance with, and pipe fittings matching the trough pipe fittings must be used. Otherwise, due to different standards, it is easy to occur a large area of unqualified pressure test, resulting in great losses.