High pressure hoses - flexible pipes, which are nested rubber (plastic) tubes with connecting fittings. Such products are particularly strong due to the metal winding or braid. With the help of RVD - high-pressure reinforced hoses - the force is transmitted in machine mechanisms, hydraulic and motor fluids are transported, water and oil emulsions.
High pressure hoses are hoses, which are made on special technology and have high characteristics
High pressure hose device
The specificity of the high pressure hose device is determined ??its purpose, operating conditions, during which it is exposed to aggressive environments and significant pressure. For this reason, for the manufacture of the inner layer use oil-resistant rubber or synthetic rubber. For the top, thickened, - wear-resistant rubber, sometimes supplemented with thermal protection coating of corrugation, metal or plastic. Between the rubber layers - laying in several layers of metal wire (or textile), translated by thin rubber films. According to the method of winding the high pressure hose can be:
- winding. Regulated by the European standard EN 856;
- braiding, when winding is carried out at an angle and the intersection of the turns leads to the strengthening of the hose. The most common type, regulated by European standards EN 853 і EN 857.
Characteristics of product quality are given by the following indicators:
- working pressure;
- temperature range of operation;
- bending radius;
- coating (top layer) hose.
The most important element of the product are fittings for mounting high pressure hoses. Possible application:
- nuts;
- couplings;
- nipples;
- fittings;
- quick connector.
RVD is a multilayer construction, often supplemented with metal wire reinforcement
Equipment for production
The equipment for release of rvt allows to make:
- metal sleeve;
- high pressure stainless steel sleeve;
- rubber;
- in a braid;
- polytetrafluoroethylene;
- thermoplastic hoses of high and average pressure. Thermoplastic is becoming more common.
The main equipment includes the following devices:
- marking machine;
- peeling machine;
- cutting machine;
- crimping press.
Additional equipment such as is also used:
- reels for winding / unwinding of hoses;
- cams;
- beds for the press.
Finished products with a long length are wound on special spools
Useful to know! For production, aimed at metallurgical enterprises and construction companies, multifunctional devices are required. Hoses for household needs are made on usual machines.
Production process, usually understood as crimping high pressure hoses, composed of such stages:
- preparatory, during which the hoses are measured and cut off;
- crimping, for which it is possible to use transverse or longitudinal methods.
- tests, designed to confirm the quality of products.
Metal sleeve and thermoplastic hose are used in countless systems, where hydro is used- or pneumatic actuators, starting from aviation and ending with utilities and household appliances.
How to perform replacement and repair of RVD
The use of crimping equipment gives the hoses high reliability. The weakest place, usually, the connection is detected, where fittings are used, which:
- affected by corrosion;
- flowing;
- lose tightness;
- come off the hose.
Fitting failure, how the hose connects to the equipment, in many cases leads to the need to replace the entire product
Among other injuries, eliminate which can repair, the most common:
- broken hoses;
- abrasion of the top layer;
- thermal damage to the internal.
Damage is caused by the following reasons:
- factory marriage. Handicraft or faulty equipment crimps the joint between the fitting and the hose;
- inconsistency of operating conditions, which leads to failure of fittings or rupture of the sleeve;
- operation of the main mechanism, when cut and torn sagging due to the wrong choice of length hoses;
- non-compliance with the temperature regime, when the outer layer of the RVD is destroyed.
RVD repair, which consists in replacing the damaged area or fitting, is carried out in the following sequence:
- after disconnecting the damaged hose, a new one of a similar size is cut on the cutting machines, focusing on the replacement of data marked.
pay attention! The measuring points are the ends of the nipples.
- when working with the so-called heavy sleeve, designed for ultra-high pressure, requires the use of a trowel for internal and external stripping of the ends of the hose, which comes to metal winding / braid;
- selection of fittings due to differences in standards, which are the focus of manufacturers, may require the use of a caliper, thread gauges and special tables;
- making a selection of fittings of the required diameter, perform crimping, using a crimping machine. Quality control is performed using a probe or testing on a stand.
With the proper use of RVD and timely replacement and repair of damaged areas and elements, reliability and proper duration are guaranteed.