What issues should be paid attention to when budgeting for water and electricity installation?
Commonly encountered problems in the installation budget
1. Regarding the electrical installation project, under what circumstances does the copper core cable terminal need to be calculated? Is it divided according to the cable cross-sectional size? ? How to calculate the project quantity? Under which circumstances is it calculated based on the cable head, and under what circumstances is it calculated based on the copper terminal?
Answer: The copper core cable head is determined according to the production process. Its process is divided into: dry package type, pouring type and heat shrink type. But sometimes the cable head is only used for simple crimping. At this time, the cable head cannot be used to make it, but the copper terminal should be pressed.
Look at the national standard atlas, which has introductions and explanations of various processes. There may be differences between the actual construction and the atlas, but you can roughly tell what kind of craftsmanship it is.
When both ends of the cable are connected to the panel, the copper core cable terminals need to be calculated. The set quota is divided according to the cable cross-sectional size. One cable has two terminals.
The intermediate head is counted as one for every 250m. It is generally not counted in the budget and will be counted as actual when it occurs.
The measurement of the cable head generally refers to the cable head when the cable enters the cabinet. Divided according to the cross-section of the cable, the dividing principle is based on the largest single core cross-sectional area.
2. Whether the price of the angle valve is included in the quota sub-item for the installation of seat toilets. Are angle valves and faucets included in the applicable washbasin installation quota sub-item? Are the prices of angle valves and faucets also included?
Answer: Every local quota has its own characteristics. In fact, no matter where the quota is, you should have an understanding of the sub-item composition of the quota you are using, and look at the composition and consumption of the work and material machinery inside. You will have a clear understanding of the questions you asked.
3. Can the quota for power cables below 35 square meters be applied to the laying of 7-core control cables through pipes?
Answer: In electrical equipment installation projects, there are special items for control cables, which are measured per 100m according to the number of cores of the cable. The effective cross-sectional area of power cables is measured in 100m. Although the quotas are the same for their work content, the base prices are quite different. I'm not very sure what tianfeng09 said about the 7-core cable. From the fact that you said it should be 35mm2 or less, I guess it's a 7×2×2.5 control cable. If this is the case, take Inner Mongolia's 2004 quota as an example: I want to apply 2--669: control cables with less than 14 cores, the basic price is 178.11 yuan/100m. If the copper core power cable cover is 2--615: power cable below 35mm2, its basic price is 313.98 yuan/100m. Cables are generally very long and plus the fee, then the difference between them is very big
4. I don’t know if everyone is prone to leaks: water supply and drainage pipe fittings (mainly traps, inspection openings , falling funnels, etc.), these quotas have no consumption, and at the same time there is no corresponding sub-item (the pricing method is to include the actual number and unit price into the sub-items)?
Answer: The inspection port cannot be applied to the sub-category and is included in the quota sub-category. The water trap depends on the situation and has a quota sub-purpose. The drain bucket needs to borrow the civil construction quota.
5. The distinction and calculation of cable heads in electrical appliances is not very clear. Do they count from 16 upwards?
Also, in the list, the amount of the pass-through box is required to be included in the comprehensive unit price of the electrical conduit. It is not very clear how the amount is determined?
Answer: 1. One cable Of course there are two terminal heads, and the use of most terminal heads starts from 16 square meters or more. The intermediate head is generally used to connect two cables. If the length is too long, an intermediate head can also be installed, usually 200 meters.
2. As for the wire box engineering quantity, it is generally installed at the corners, lamps and switches and sockets. In addition, if the straight line length is too long, a junction box should also be installed to facilitate maintenance. In previous estimator training courses, the teacher recommended adding a junction box every 28 meters of straight line section.
6. A ventilation duct with a diameter of 830mm is made of steel plate: 1. Calculated on what basis? 2.
What quota applies? 3. Are elbows calculated separately? Are losses subject to the cap? (The elbow is made in three sections) 4. Should the tee be inserted according to the pipe fitting or according to the welding cut?
Answer: 1. Calculated according to the ninth volume of the installation quota: quota 9-11
2. The air ducts are calculated according to the different specifications noted in the diagram to expand the area, including inspection holes, measurement holes, The area occupied by the air supply outlet, air suction outlet, etc. is not deducted; when calculating the length of the air duct, the length of the center line of the legend shall be used as the standard, including the length of elbows, tees, reducers, Tianyuan and other pipe fittings, but parts shall not be included The length of the location. The diameter and circumference are expanded according to the dimensions in the figure, and the overlapping parts of the bite are not added; the thin steel plate ventilation duct production and installation sub-item includes elbows, tees, reducers, Tianyuan and other pipe fittings, flanges, and reinforced frames. and hanging brackets, excluding over-span duct floor-standing brackets. The floor-standing bracket applies to the equipment bracket sub-category; the plates in the thin steel plate air duct sub-category can be converted if the design requires different thicknesses, but the labor and machinery remain unchanged.
7. Does single-phase refer to one live wire? Three phases are three live wires?
Answer: Single-phase refers to one live wire and one neutral wire, used for general lighting. Three-phase refers to three live wires and one neutral wire, which is used for things like motors~~~. Single phase: 220V, three phase: 380V. It's just that the neutral line is not mentioned, it is the so-called three-phase four-wire, and the three-phase five-wire has an extra PE ground wire.
8. Rocker type (single control) single-gang switch. What does single-control single-gang mean?
Answer: A single-link switch is a switch with only one rocker on the panel. There are also double-link, triple-link, quadruple-link, etc., which are easy to recognize. The so-called single control refers to the control circuit of the switch. Generally speaking, if there are two control loops, it is called double control, and one is single control~~~ Attached: Picture of single switch and picture of double switch
9. Diameter is often seen on design drawings A floor drain with a diameter of 100 and a floor drain with a diameter of 50. Does diameter 100 and diameter 50 refer to the pipe connected to the floor drain, or does it refer to the diameter of the floor drain cover?
Answer: The diameter of the floor drain refers to the diameter of the drainage pipe connected to it.
10. Where are the ground disconnect clips generally located? What is a ground terminal box? What is equipotential?
Answer: The purpose of the grounding terminal clamp is to test the resistance of the lightning protection down conductor. It is generally located on the outdoor skirting of the exterior wall. The grounding terminal box is a terminal box specially used for grounding the distribution box. Inside the box is a grounded copper bar. Equipotential bonding is to connect the exposed metal and conductive parts of various electrical devices and other devices in the building with artificial or natural grounding bodies and conductors to reduce the potential difference, which is called equipotential bonding. Equipotential bonding includes total equipotential bonding, local equipotential bonding and auxiliary equipotential bonding.
11. When bidding for a project, how should the weight of the brackets of the water pipes be calculated? Generally, the position of the brackets will not be marked on the drawings. If calculated according to the specifications, the project volume will be very large. During the bidding time It is difficult to complete when it is short. I usually multiply the coefficient by meters, usually 1.5. But sometimes this calculation will exceed the actual situation. Is there any other method?
Answer: The calculation is based on a spacing of about 1m. Please check the atlas for the specific steel model used. It is explained above that the calculation result will not be very large.
Every 10,000 square meters of building area is calculated as 1 ton of brackets, which refers to ordinary residences. Complex ones must be calculated according to specifications!
Indoor pipe brackets below DN32 are already included in It is included in the sub-heading. For the brackets on the risers larger than 32 meters, one bracket will be set on each floor with a floor height not exceeding 4 meters. Flat pipes are generally set at 1.5 meters to 2 meters, and the number of turns will be increased. In addition, the large pipes stipulated in the specification must be referenced. diameter and maximum overhead distance.
12. Which symbols in the system diagram are useful for calculation? For example, Ps=131, kX=0.8 Pjs=104.8Kw 75A 105A YJV3×25 16PC32QA BV3×10PC32QA, etc. There are many other symbols. Can anyone tell me in detail?
Answer: Generally speaking, if you are just doing calculations, you only need to master the following two parts~~
"YJV3×25 16PC32QA" refers to the YJV-3×25 16 cable The pipe passing through PC32 is laid concealed along the wall (QA);
"BV3×10PC32QA" refers to the BV-3×10 line passing through the PC32 pipe and laid concealed along the wall (QA).
13. Where are the control cable ends generally located? Where is the middle head? What are terminal headers and intermediate headers?
Answer: The cable terminal refers to a connection and maintenance terminal made when both ends are connected to equipment such as distribution boxes during cable laying, so a cable in a system is There are two terminal heads! As for the intermediate head of the cable, it refers to a joint made by connecting two cables due to insufficient length of the connecting cable in the middle of a system or other reasons. However, this approach is generally not allowed. The cable connection in a system is generally Intermediate disconnection is not allowed~~so intermediate headers generally do not exist~~~
Cable terminals are divided into outdoor and indoor ones, and intermediate headers are also available. When the cable length exceeds one reel When the cable reaches its maximum length, an intermediate head must be made; the rating book also states that when the cable length exceeds 250 meters, an intermediate head must be considered.
14. What is the difference between outdoor and indoor cable terminals? What is a pin insulator? What is the top of the road pipe?
Answer: Pin insulators are wired on utility poles. They are the stuff on the crossbars, commonly known as blockers. They are usually white and porcelain. Jacking of road pipes means that when the line crosses the street, excavation of the road surface is not allowed, and pipe jacking is used for construction.
15. When debugging the control device of the water fire extinguishing system, how is this system divided? Is the entire water fire extinguishing control cabinet considered a system, or is the control box of the deluge valve group considered a system?
Answer: According to the "Full System Engineering Quantity Calculation Rules", the points of the water fire extinguishing system are calculated according to the points of the linkage control.
16. Which subheading is the 33.5×4 PP-R pipe sleeve?
Answer: The nominal diameter specifies a standard diameter for pipes and pipeline accessories. This standard diameter is called It is the nominal diameter or nominal diameter. The nominal diameter is expressed in DN. Why do we need to determine the nominal diameter? Due to different uses, pipes with different outer diameters are required. Pipes with the same outer diameter have different inner diameters due to different wall thicknesses. In addition, the pipeline system also requires a variety of pipeline accessories corresponding to the diameter, including pipe fittings, valves and flanges, etc., resulting in a large diameter of pipes and accessories, causing difficulties in manufacturing, design and construction. In order to enable mass production, reduce costs, reduce the storage of spare parts, and make pipes and pipeline accessories interchangeable, pipes and pipeline accessories should be standardized, which resulted in the nominal diameter. To measure the size of a pipe, the outer diameter of the pipe wall, known as the outer diameter, and the diameter of the inner wall, known as the inner diameter, are usually used. The inside diameter of valves and cast iron pipes is usually equal to the nominal diameter. The actual inner diameter and outer diameter of the pipe are generally not equal to the nominal diameter, but its inner diameter is close to the nominal diameter. For example, a welded steel pipe with a nominal diameter of DN100 for low-pressure fluid transportation has an outer diameter of D114 and an inner diameter of d106. PP-R pipes are mainly used in cold and hot water pipe systems, drinking water systems and heating systems (including floor radiant heating) in industrial and civil buildings.
In Europe, the use of PP-R pipes in building cold and hot water pipe systems is relatively common, and has gradually become the leading product. Some people predict that in the field of indoor water supply pipes, PP-R pipes will be a newer and better choice for people, and have more development prospects than cross-linked polyethylene pipes and aluminum-plastic composite pipes.
17. In building water supply and drainage installation projects, how should the quota be set when installing aluminum-plastic PP-R water supply pipes? Should aluminum-plastic composite pipe sleeves be used, or PP-R pipe sleeves? (Hot-melt connection)
Answer: When the indoor water supply and drainage pipeline system is installed, as long as it meets the conditions of "the water supply is galvanized steel pipes, and the drainage is socket cast iron drainage pipes or plastic drainage pipes", the comprehensive quota can be applied For corresponding projects, some materials can be converted; aluminum-plastic composite pipes shall comply with 8B-634~639, and flexible drainage cast iron pipes shall comply with 2-3-174B~178B.
18. Which kind of lamps should be installed when installing the cost quota for emergency lighting fixtures?
Answer: Emergency lighting is generally divided into two situations. The first is to use backup Sub-circuit --- and separately setting up what is commonly called an accident lighting circuit. In this case, it is indeed treated as ordinary lamps during construction, and the budget should also be treated as ordinary lamps and lanterns. However, in the second case, wall-mounted lamps are used. Finished emergency lighting - it has the same installation method as safety exit lights, evacuation sign lights, safety door lights, etc. (directly hung on the wall), and the external wiring method is also the same. The only difference is that the bulbs used are high-voltage A bright DC bulb with a reflective bowl (but the inside is a battery and a control circuit). In this case, I think it would be more appropriate to apply the sign and induction light sub-items. The budget for the wind and rain playground of the Municipal Engineering College that I am currently building is also This is exactly how it is done. As for the battery-inverter-incandescent lamp form of emergency lighting proposed by some netizens in the forum, due to the instability of the inverter and the unsafe factors of normal voltage (220V), there is no I won’t say much more about the official use in the project
19. How should the inspection port of the indoor flange-connected cast iron drainage riser be measured? Whether its installation fee and material fee are included in the drainage Are you in the management quota? Do I need to calculate it separately?
Answer: According to the installation of pipes and joints in Article 1 and Article 6 of the quota description, cast iron drainage pipes, rainwater pipes and plastic drainage pipes all include pipe clamps and hanging brackets, odor caps, and rainwater funnels. . Therefore, the labor for installing the inspection port is included in the installation of the cast iron drain pipe, and there should be no additional installation fees, but the price of the joint parts will be calculated separately.
20. I would like to ask if the following "fluorescent lamps" are wired at one end or in the middle. That is, the position of the junction box of the lamp is at the end or in the middle. , only by knowing this can I calculate the exact length of the thread in the tube! For example, if the fluorescent lamp and the wire are in a straight line, when calculating, should you count the end of the fluorescent lamp or the middle! Since I have no practical experience, please help me answer the following~
Answer: According to the characteristics of the lamp, the wiring port is usually left in the middle. Maybe some fluorescent lamps have the wiring port at the end. The wiring port is in the middle, but when calculating this, we can only take an average number, that is, calculate based on the middle position.
21. Which sub-item of the quota should be included in the local equipotential terminal box and the general equipotential terminal box?
Answer: The general equipotential terminal box can apply to the 2-263 quota, while the partial equipotential box can apply to the 2-1375 junction box quota. The reason is that the local box is equivalent to a junction box or box, and there are terminal strips in the overall box.
According to the Zhejiang 03 quota description: the connection in the equipotential box refers to the "ground jumper" sub-item. Each box is 1 point, with 10 points as the measurement unit, and the quota is multiplied by a coefficient of 0.5.
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