1. Construction of base concrete
When constructing the base concrete structure, try to use larger-sized crushed stone and high-grade commercial concrete to ensure the capacity of the concrete. When pouring, make sure the concrete is vibrated evenly and densely. Do not dehydrate it during the maintenance period. When removing the formwork, try to minimize the impact on the concrete to prevent fine cracks from occurring during the demolding, which may cause rays to penetrate directly and splash out.
2. Machine room masonry construction
The masonry of the computer room should be made of solid red bricks, and it is recommended to use cement mortar for masonry. During masonry, the flatness and verticality of the wall should be ensured to be horizontal and vertical, and the density and fullness of the masonry mortar should be ensured to be above 90%, otherwise it will easily lead to direct penetration of radiation and waste of radiation protection materials.
3. Construction of equipment foundation in the computer room
According to the drawings provided by the factory, the lines should be positioned in the computer room first, and then handed over to the design institute according to the equipment load. Do a technical review first, then pour the foundation. When pouring the foundation, determine the position of the embedded bolt rod or reserved screw hole (very important, must be accurately embedded) according to the drawing for the installation of the machine. If the embedded parts are not accurate or the holes are opened afterwards, it is easy to cause the foundation to crack and the machine base to loosen after installation. After the foundation is poured, it should be leveled within 2 hours, otherwise it is easy to peel off and make the machine installation unbalanced. If the above situation occurs, it will bury hidden dangers to the accuracy of instrument detection.
4. Positioning of the machine and the top and bottom brackets
Generally, the positioning of the machine is relatively simple. It can be installed by a professional manufacturer after the construction of radiation-proof doors and windows and anti-fouling coatings is completed. However, large equipment such as ECT must have a hole to ensure that the machine enters the room. After the machine arrives on site and enters the room, the wall can be sealed and the door frame and door leaf can be installed. If such instruments have ceiling brackets in place in the future, the weight of the instrument to be hung must be considered when it is in place, and then the bracket specifications are selected. When installing the bracket, the horizontality of the beam and the verticality of the side must be achieved. The two ends should be placed on more than 2/3 of the 240 wall. The placement points should be padded with steel plates or concrete bodies of not less than 240*500, and a small triangular bracket should be welded upside down on the side of the bracket and the wall to ensure that it can bear the weight of the machine. The distance between the bracket and the ground instrument should be ensured by the data provided by the cabinet factory, otherwise problems such as inaccurate detection will occur. The holes for installing the pendant instrument rails on the bracket should be opened before the bracket is installed to ensure the accuracy of the holes.
5. Installation of computer room doors and windows and treatment of door and window gaps
255);"/>After the masonry construction is completed, anti-fouling glass and anti-fouling doors should be installed. After the anti-fouling glass is installed, a frame should be added around it, and a lead plate not less than 3mm thick (equivalent to 3 lead equivalents) should be installed in the frame. First, insert it into the wall 2cm or make a window cover. Use the lead plate to wrap along the window sill to the wall, covering the gap of more than 3cm, or use anti-fouling paint to paint the thickness of more than 3cm. The overlap between the lead plate and the lead glass should be no less than 2-3cm, otherwise it is easy to cause the radiation to refract and penetrate. After the anti-fouling door is installed, a gap will be generated between the door frame and the wall. Therefore, the lead plate is wrapped to 5cm from the wall at the gap, and the edge of the frame is pressed 3cm away from the edge. The blockboard, decorative panel, and door cover are pasted on the exterior wall. When making the door cover, nails must not be used to penetrate the lead plate in the vertical direction (ray direction) of the wall, otherwise the rays will leak out. It is best to use glue to bond. The overlap of the lead plate at the door should be more than 1.5cm. The door lock is also a difficult point for radiation protection and should be strictly handled. The threshold of the machine room should be different according to the purpose and the needs of the patients, so that the cart can be pushed and pulled and ensure stability. The threshold is equipped with a 3mm thick lead plate to prevent radiation from passing through the gap. However, before installing the door and frame, it must be ensured that the machine can enter or let the machine enter first.
It is recommended that lead glass should be 18-21mm thick, equivalent to 3-4 lead equivalents (there is no wall here); the lead plate on the door and door and window frames should be 3-4mm thick, equivalent to 3-4 lead equivalents (from here to the wall).
6. Control of machine radioactive sources
When antifouling paint is used around the machine room, the strength of the radiation source emitted by the machine should be considered. Lead plates (the specific thickness is determined according to the equivalent of the machine's radiation) should be placed on the upper floor or the bottom of the machine to prevent the radiation source from penetrating the general protection requirements in the direction of strong radiation, thereby affecting the medical staff, patients and family members working in the machine room or department next to it. It is also possible to thicken the antifouling paint on the upper floor or the floor where the radiation source will generate strong radiation to reduce radiation pollution and avoid injury.
7. Saving measures for the construction of radiation protection coatings
255);"/>Radiation-proof paint is a kind of metal fine particles and stone powder composed of various metal elements and chemical raw materials. If the thickness reaches the general requirements, it will be able to fully resist the penetration of anti-pollution rays and absorb some rays. There are few manufacturers of this material, so the price is relatively high, generally 4000-4800 yuan/T. This material is generally used for painting the walls of computer rooms. Due to the high price, unnecessary waste should be minimized when painting.
1. The quantity of mixed materials should be determined according to the construction area of the day. The principle is to use as much as possible to prevent the material from solidifying (generally, the thickness of a flat wall is 40m2/t-1cm). It is best to ensure that it is used up within 2 hours from the time of discharge to the time of construction.
2. Strictly implement the construction plan in advance to prevent cracking and falling off, so as not to cause consumption.
3. It is recommended that the project should be primed before painting, because there will definitely be some uneven places or gaps in the brick joints when the brick wall is built, especially on the reverse wall, which will cause a lot of consumption, and the thickness is uneven and cannot be controlled. Because the reverse wall may have uneven thickness of 3cm or more, we think it is necessary to use cement mortar to prime and level it, but not too thick.
8. Technology and requirements for the construction of radiation-proof coatings
2. Let the wall be moistened to 70% before applying the cement sand primer.
3. When the antifouling paint is thick, it should be applied in several coats, with each coat not exceeding 5-8mm. The interval time is generally 8-2 hours (it is advisable to wait until the wall is 70% dry).<br style="color: rgb(102, 102, 102); font-family: "Microsoft Yahei", Verdana, Geneva, sans-serif; font-size: 13px; text-align: justify; text-wrap: wrap; 4. Open windows at the construction site to ensure ventilation. The temperature should not be lower than 15℃ to prevent vertical cracks caused by the wall not drying out.
5. When painting, press from bottom to top and do not push and pull repeatedly. Do not press the base to make it smooth. Just keep it flat. Press and roughen the surface for the last time to prevent cracking and falling off.
6. When mixing materials, 0.3-0.5kg of special adhesive is required per square meter. The ratio of paint to cement is 5:1.3, which generally cannot exceed 5:1.5. Add appropriate amount of water, mix the paint and cement first, and then stir them together.
7. During the coating construction, we will hire and appoint professionals to provide on-site guidance to ensure quality, save materials, and meet the acceptance requirements of antifouling coatings.
After the wire conduit is grooved, it should be fixed first, and then painted with cement sand until the bottom is flat, and then painted with anti-fouling paint. The wire conduit cannot be in the paint layer of anti-fouling paint, so that the wire conduit can be cut open to prevent radiation leakage. Lead plates or paint should be added behind the distribution box, fire box and switch socket, and both sides should extend at least 5cm to ensure that the radiation does not leak.
X. Precautions for the construction of the machine room floor and wainscot (wall skirt)
2. Floor construction may cause the same problem as wall skirts, which can be remedied by the above method. The cable trench in the computer room is generally lower than the normal floor, so it is impossible to level it with paint. At this time, use a 3mm thick lead plate to make a groove and pad the cable trench. The cable trench cover in this room, such as the control room, corridor and computer room, is preferably a movable floor.
11. Darkroom construction should ensure the darkroom ventilation system, but also absolutely ensure that there is no light. The darkroom sink is best made of porcelain to prevent oxidation and chemical corrosion, but stainless steel and other materials can also be used.
12. Matters needing attention
1. Apply primer (with cement mortar) before painting to reduce unnecessary waste of paint materials.
2. Use wire mesh to lay at the contact point between brickwork and concrete to prevent cracking and falling off and radiation leakage, because once cracked, it will be very difficult to repair, and there will be a small crack, and the material will be consumed.
255);"/>3. The thickness of the lead plate for protective doors is 3-4mm, equivalent to 3-4 lead equivalents, and the thickness of the door overlap is controlled at 1.5cm. Door covers are added to the door seam and the bottom of the door, and lead plates are padded inside the threshold.
4. The thickness of the paint is generally 3-4c for ECTm thick coating, equivalent to 3-4 lead equivalents, which is determined according to the selected instrument and manufacturer's requirements.
5. Lead glass 18-21mm thick, equivalent to 3-4 lead equivalents, because this place is the operating place for medical staff and is also exposed to radiation.
6. Lead plates or thick anti-fouling paint should be used above and below the machines in the computer room.
7. The walls of the computer room control room should be painted on both sides, and ventilation should be ensured to ensure the safety of medical staff.
8. It is best to put the paint ceiling on the floor above, so that it is not easy to cause the paint to fall off due to vibration of the floor or poor bonding.
9. Pay attention to the nail holes that penetrate the paint layer or lead plate layer during decoration.
10. If the coating is above 2.2mm, the thickness of the painting can be relatively reduced (but it is difficult to construct) to reduce costs. The specific requirements are determined according to the manufacturer's requirements and the owner's arrangement.