Chita D｜Production process of stainless steel stairs, railings, and handrails

1. Material: stainless steel railings, 201 and 304 stainless steel decorative pipes are commonly used, 201 stainless steel is mainly used for indoor use, and 304 stainless steel is mainly used for outdoor use.

2. Structure: Mainly have all stainless steel structure, glass stainless steel structure, wooden stainless steel structure.

3. Height and spacing: when the airborne height is below 24, the railing height should not be less than 1.05 meters, and when the airborne height is 24 meters and above, the railing height should not be less than 1.10 meters; the railings should be prevented from climbing, vertical poles The net distance between pieces should not be greater than 0.11 meters.

(1) When Party A does not have construction drawings, the actual site survey and measurement shall be notified by Party A. The main contents are as follows:

A. Length of stairs or handrails;

B. The number of steps on each floor;

C. The condition of the staircase surface (whether there are tiles, whether there are embedded parts, etc.);

D. The condition of the wall at the junction of the railing and the wall;

E. The surrounding environment of the proposed railing, the nature of Party A’s unit and Party A’s initial requirements;

F. Material handling methods and material storage points;

G. Construction power supply overlap point at the construction site;

H. Party A’s requirements for construction time (noisy welding, grinding, polishing, etc.);

I. Coordination work during cross operation and safety measures during construction.

(2) When Party A has construction drawings, it shall conduct surveys on the construction site in combination with the drawings. The main contents are as follows:

A. Whether the length of the stairs or handrails is consistent with the construction drawings;

B. The number of steps on each floor;

C. The condition of the staircase surface (whether there are tiles, whether there are embedded parts, etc.);

D. The condition of the wall at the junction of the railing and the wall;

E. Material handling methods and material storage points;

F. Construction power supply overlap point at the construction site;

G. Party A’s requirements for construction time (noisy welding, grinding, polishing, etc.);

I. Coordination work during cross operation and safety measures during construction.

(1) When Party A does not have construction drawings, according to the site survey, combined with the surrounding environment of the railing to be made, the nature of Party A’s unit and Party A’s initial requirements, design two to three sets of styles (railing or handrail), indicating each type The advantages and disadvantages of the style, the materials used and the price shall be reported to Party A for review and confirmation, and the construction contract will be signed after Party A is confirmed.

(2) When Party A has construction drawings, it shall communicate with Party A and quote the price based on the construction drawings and on-site surveys, and sign the construction contract after Party A confirms.

The construction contract is signed according to the construction drawings and prices confirmed by Party A. The main contents include: total contract amount, advance payment, construction period, completion settlement date, warranty period, warranty money, payment method, liability for breach of contract and other terms.

(1) Technical preparation: Be familiar with the construction drawings confirmed by Party A and make preparations for construction.

(2) Material requirements:

A. The wall thickness specifications, dimensions and shapes of stainless steel railings should meet the design and construction requirements. Generally, the wall thickness is not less than 1mm, and the wall thickness is not less than 2mm when steel pipes are used as the poles; wooden handrails are generally processed into finished products with hard wood , Its tree species, specifications, size and shape are in accordance with the design requirements. The wood itself should have a straight grain and consistent color. There shall be no defects such as decay, knots, cracks, distortions, etc.; the moisture content shall not exceed 12%. The elbow material generally adopts the handrail material. Connect with 45° section.

B. The thickness of the glass fence shall meet the design requirements, and the tempered glass or laminated glass shall not be less than 12mm, and the tempered glass shall have a retest report for entering the site.

(3) Main machines and tools:

Electric welding machine, argon arc welding machine, welding rod, welding wire, polishing machine, polishing sheet, polishing wax, electric hammer, cutting machine, marble machine, portable electric drill, plane, small and medium wood saw, hammer, axe, steel file, screwdriver, square ruler Wait.

(4) Operating conditions:

A. The walls and stairs are plastered before construction.

B. The metal railings and the fixed supports against the wall handrails have been installed.

(1) The main materials such as stainless steel and glass should be handled gently when getting in the car, wrapped with soft materials such as flannel and fixed firmly with a rope, so as to avoid scratches, damage and Slipped off the road.

(2) Check whether the auxiliary materials, labor protection supplies, and tools required for the project are fully loaded on the vehicle. In case of rain, a tarp should be set up to prevent the materials and tools from being damp.

(1). Store materials and lap the construction power supply according to the location designated by Party A, and the construction power lap needs to be operated by a professional electrician with an electrician certificate;

(2) Process flow:

Positioning and setting-up→installation of fixings→welding poles→installing stone cover plate (when the ground is stone ground)→welding handrails and fixed flat steel (fixed flat steel tied wooden handrail craft)→processing glass or wrought iron railing (manufacturing) Glass and wrought iron stainless steel railing) → polishing → wooden handrail installation (making wooden handrail stainless steel)

(3) Operation process

A. Positioning and laying line: According to the requirements of the construction drawings, the spacing, position, elevation, and slope of the fixed parts are found and corrected, and the longitudinal center line of the railing and the position line of the grid are popped up.

B. Installation of fixing parts: According to the position line of the fixed parts to be ejected, drill holes on the ground with a percussion drill, and then install expansion bolts. Each fixing part shall not be less than 2 expansion bolt fixing screws of Φ10 and length not less than 100mm. After the bolts are positioned, tighten the bolts and weld the nut and the screw to prevent the nut and the steel plate from loosening. The connection between the handrail and the wall surface also adopts the above method. Welding pole: When welding the pole and the fixed parts, the upper and lower pole position lines should be released, and each main pole should be spot welded and positioned. After checking the verticality, it is fully welded in sections. When welding the column, Two people are required to cooperate, one holding the steel pipe to keep it vertical and not shaking during welding, and the other for welding, and welding must be performed on all sides. The welding seam meets the design requirements and construction specifications. After welding, the welding flux should be cleared and anti-rust treatment should be carried out.

C. Install the stone cover plate: When the ground is a stone floor, when a whole piece of stone is installed at the railing, after the pole is welded, the stone is opened and placed on the pole according to the position of the pole. The size of the opening should ensure that the flange of the railing can be tightly covered. Cement mortar should be used when installing the cover. The fixed stone can strengthen the stability of the upright railing.

D. Flat steel for welding handrails or installing wooden handrails: A. When using stainless steel pipe handrails, use an argon arc welding machine for welding. Spot welding should be used first. The angle of inclination and the roundness of the armrest used are processed with a fork at the upper end. Then put the handrail directly into the fork of the column, and install it by spot welding from one end to the other. The adjacent handrails are installed accurately and the joints are tight. After the adjacent steel pipes are butt jointed, the joints are fully welded on both sides with stainless steel welding rods at the same time. B. After welding, oil stains, burrs, rust spots, etc. within the range of 30-50mm along each side of the weld must be removed. The weld seam should not be too long at one time to prevent the steel pipe from being heated and deformed. C. Before installing the square and round steel pipe poles and wooden handrails, the flat steel fixing parts of the wooden handrails should be pre-punched, and the spacing should be controlled within 400mm before welding. The verticality and straightness of the spacing after welding should meet the quality requirements. D. When making the auxiliary pipe connection, the distance between the auxiliary pipe on the ground and the floor of the ladder step is between 18cm-25cm. When the floor tile is not installed on the tile, the height of the floor tile should be determined.

E. Processed glass or iron fence: The glass fence should be processed and installed according to the drawings or design requirements and the actual size of the site. The sides and external corners of the glass should be thrown into beveled or rounded corners to prevent hand injury.

F. Polishing: After the stainless steel pipe is welded, the surface is polished with a coarse 80-fiber blade. If there is any unevenness on the surface, argon arc welding can be used to repair it. After the large surface is smoothed, the second time is polished with a 240-fiber impeller. , And polish the third time with a 320-fiber impeller. When polishing, use flannel grinding wheel or felt to polish, and use the corresponding polishing paste at the same time, until it is basically the same as the adjacent base material, and the welding seam is not obvious. When the welds of square and round steel pipes are polished, they must be flat and vertical. After anti-rust treatment, the welding seam and the uneven surface can be filled with putty and polished.

G. Wooden handrail installation: The wooden handrail should be installed from bottom to top. First, pre-install the elbow, that is, connect the bending elbow of the first section of the handrail. The temperature shall not be lower than 5℃, the pre-installation inspection is correct, the handrail and the railing handrail are fixed, the flat steel on the railing is tightened and fixed with wood screws, and the fixed distance is controlled within 400mm. During operation, drill the handrail material at the fixed point, and then screw in the wood screw. Do not use a hammer to directly nail the screw cap. Use the handrail material to glue the bend of the handrail. If there is any irregularity, use a fine wood file to file and smooth it to make the corner line clear, the slope angle is appropriate, the curve is natural, and the section is consistent. Finish with sandpaper.

H. The welding process requirements used when assembling stainless steel railings and stainless steel handrails:

① Use low current, fast welding and narrow welding bead to prevent cracks and deformation.

②. Adopt DC welding machine with reverse polarity (workpiece is negative pole, motor is positive pole).

③ For short arc welding, take the arc slowly and fill the arc crater.

④ The surface contacting the corrosive medium is welded last.

⑤. Forced cooling can be used after welding, such as water cooling, air cooling, etc.

⑥ The deformation after welding can only be corrected by cold working.

(1) Quality details during installation 1. Installation and primary treatment should meet the following requirements:

A. The design elevation, position and quantity of embedded parts must meet the design and installation requirements, and be treated with corrosion and rust prevention. When the embedded parts do not meet the requirements, effective measures shall be taken in time to supplement the embedded parts.

B. At the location where the stair railings are installed, the base concrete must not be loose, and the installation elevation should meet the design requirements, the unevenness must be removed or repaired, and the recesses and the serious honeycomb surface of the base must not be repaired with cement mortar. , The use of high-strength concrete for repair, and after a certain strength, the railing can be installed.

2. According to the design and installation requirements, the installation distance and center line of the railing pole should be correctly popped up.

3. The main points of installation and operation of stainless steel stair railings and handrails:

A. The installation of the railing poles should be carried out in accordance with the requirements and the order of the construction ink line upwards from the starting point. The poles at both ends of the platform at the starting point of the stairs should be installed first. The installation can be divided into two methods: welding and bolting.

B. During welding construction, the welding rod should be made of the same material as the base material. During installation, the pole and the embedded part should be temporarily fixed by spot welding. After the elevation and vertical correction, the welding should be firm.

C. When bolts are used for connection, the holes on the metal plate at the bottom of the pole should be processed into round holes to prevent the position of the expansion bolts from being inconsistent. Minor adjustments can be made during installation. During construction, use an electric drill to drill the expansion bolts at the base of the installation pole, connect the pole and fix it slightly. If there is an error in the installation elevation, adjust it with a metal thin gasket. After the vertical and elevation corrections, tighten the screws. cap.

D. After installing the poles at both ends, use the same method to install the remaining poles by pulling the cable. The pole installation must be firm and not loose. The pole welding and bolt connection parts, except stainless steel, should be treated with anti-corrosion and anti-rust treatment after installation, and should not be exposed, and a decorative cover or cover should be installed at the root.

E. When the panel is fitted with a fence, the fence should be installed after the pole is completed. The installation must be firm, and the vertical, horizontal and inclination should meet the design requirements. When installing, insert the railings into the grooves of the vertical poles on both sides. The gaps between the grooves and the two sides of the rails should be filled firmly with hard rubber strips. After the handrails are installed, they should be embedded with sealant. When the handrails are welded and installed, the fence should be covered with fireproof asbestos cloth to prevent damage to the fence by welding sparks.

F. The installation of stair handrails is generally welded (except for special sizes). The material of the electrode used should be the same as the base material. The installation sequence of the handrails should start from the starting elbow, followed by the straight handrails. The armrest interface should be cut correctly according to the required angle and filed with a metal file to avoid inaccurate cutting, causing the armrest to bend and difficult to install. When installing, first fix the starting point elbow and the railing pole by spot welding, and weld it firmly after the inspection is correct. After the elbow is installed, the two ends of the straight handrail are temporarily fixed by spot welding to the two ends of the vertical poles, and at the same time, one end of the straight handrail is connected by the head and fixed by spot welding. The handrails are fixed to each pole by spot welding. After the inspection meets the requirements, the joints and the handrails and poles are welded firmly one by one according to the welding requirements. When welding (especially in winter construction), the welding current, voltage and welding temperature should be mastered to prevent the current from being too large or too small and the voltage is unstable, which affects the quality and appearance of the welding. The welding quality should meet the relevant standards, the width and depth of the weld should be consistent, the surface should be fish-scale, the weld of the handrail joint should be tight, and the weld should have no obvious feel deviation.

G. After the installation of long metal handrails (especially outdoor handrails), the joints should be considered to install movable interfaces that can adapt to temperature changes and expand and contract. The expansion and contraction of movable joints, if the design is not required, generally consider 20mm . Outdoor handrails should also consider setting up leaking holes at the retractable place. The connection between the root of the handrail and the surface of the concrete and brick wall should generally adopt a retractable fixing method to avoid bending and deformation of the handrail due to expansion and contraction. A decorative cover should be installed at the root of the connection between the armrest and the wall.

(2) Common quality defects and prevention measures of stainless steel railings

1. Common quality problems:

A. The surface brightness of the pipe is not enough, the color is dark, and the color difference on the surface of the titanium-coated pipe is large.

B. The overall rigidity of the railings and handrails is not enough, and there is a sense of tremor when tapping the handrails.

C. The column is not vertical, the arrangement is not on the same straight line, and the shaking is not firm.

D. The corners of the handrail are not smooth.

E. There are gaps in the joints of the pipes.

F. The arc of the arc-shaped handrail is not smooth, and there is a split edge.

G. The pipe wall at the weld is ground through, and the degree of polishing is not enough.

H. There are scratches and pits on the surface.

2. Prevention measures:

A. First of all, pipes with qualified quality should be selected. Different grades of pipes have different element content. Even if titanium is plated in the same factory, the surface color of the finished product is also different. Therefore, attention should be paid to the selection of stainless steel pipes of the same category and grade, and the quality management of the titanium plating process should be strengthened.

B. Because the selected pipe wall is too thin, the overall strength is insufficient, so pipes with wall thickness ≥ 1.2mm should be used as handrails. The pipe diameter of the riser should not be too small. When the length of the straight section of the handrail is long, the design of the upright should be strengthened with lateral stability.

C. Inaccurate spring line, improper installation method. During construction, the line must be accurately elasticized. First, use a level ruler to correct and fix the reference uprights at both ends, and then pull through the lines to fix each upright according to the positioning of each upright. The embedded parts should be checked before welding, and the buried rods that are found to be problematic should be reinforced. The expansion bolts used to fix the base of the column should be prevented from being too short, or the cement mortar layer under the facing stone is not full. The quality inspection of each construction process should be strengthened in order to correct quality problems in time.

D. The processing technology is not high. Right-angle elbows produced by professional factories should be used as much as possible. Non-standard angle elbows can be specially processed according to the detailed construction drawing. The processing plant should have special production equipment.

E. The welding should be fully welded. An experienced welder should be dispatched for construction, and the construction should be carried out in strict accordance with the operating regulations. It is best to use lined casing.

F. Because there is no special equipment for processing and forming, the positioning of the column is not accurate. A factory with special equipment should be selected for processing, and the quality inspection of processed components should be strengthened to prevent unqualified products from flowing into the construction area.

G. Because the wall thickness of the selected pipe is too thin, it is easy to dent when processing the elbow, and the roundness of the pipe is changed, and there is no additional lining sleeve during butt welding, so that when the weld is flattened after welding , It is easy to grind and penetrate the tube wall at one end of the drum. Pipes with appropriate thickness should be selected, and it is better to add lining sleeves when butt welding.

H. The finished product is improperly protected, and it is collided or scratched by objects in the cross operation. The construction process should be arranged reasonably, and it is best to arrange the handrail installation work to the later stage. The finished railings and handrails should be isolated and protected as necessary to prevent collisions and scratches by foreign objects.

1. The stainless steel pipes and wooden handrails entering the site should be stacked with chocks to prevent surface damage or deformation.

2. After the glass enters the field, it must stand against a firm structure or a special glass shelf, fix it with a rope and take measures to prevent rain.

3. When the railing is installed, if the ground stone is installed, the finished product should be protected during the handrail construction to prevent welding sparks from burning the ground.

4. After the wooden handrails are installed, they should be painted with a primer, and they should be wrapped. One side is damaged by impact and discoloration due to dampness. The glass railings and stainless steel handrails should be protected by wood to prevent damage.

1. After the construction is completed, the construction site shall be cleaned up and no dead ends shall be left.

2. The construction waste is collected and stacked at the designated location.

3. Cleaning of construction equipment.

4. Provide the completion acceptance report and ask Party A to accept it and sign it.