Design & SizingCâu 21 / 110
A booster pump must deliver 40 gpm and raise pressure by 45 psi. Using approximate water horsepower WHP = (gpm x psi) / 1,714, what is the water horsepower required (before pump efficiency)?
a.1.05 hp
b.0.5 hp
c.2.1 hp
d.4.2 hp
Giải thích
WHP = (40 x 45) / 1,714 = 1,800 / 1,714 = 1.05 hp. This is the ideal hydraulic power; the actual motor must be larger to account for pump efficiency, often around 60 to 70 percent. Dividing the delivered fluid power by efficiency gives the brake horsepower to specify.
Trích dẫn luật: UPC §610.0Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Using the rational method Q = 0.0104 x A x i, where A is the projected roof area in square feet and i is the rainfall rate in in/hr, what is the design storm flow for a 6,000 ft^2 roof at a 3 in/hr rainfall rate?
- A roof drains 4,800 ft^2 at a design rainfall rate of 4 in/hr. Using Q = 0.0104 x A x i, what is the storm design flow?
- A storm sizing table is published at 4 in/hr. A vertical leader lists a capacity of 4,600 ft^2 of roof at 4 in/hr. If the local design rate is only 2 in/hr, what roof area can that same leader serve?
- A booster pump adds 52 psi. What is the equivalent head, in feet, that the pump develops? Use 1 psi = 2.31 ft of head.
- A recirculation loop must deliver 6 gpm of hot water. Using v = 0.408 x Q / d^2, what inside diameter keeps the velocity at about 2 ft/s to limit erosion of the continuously circulated hot line?
- A water main runs 250 ft of developed length and the friction chart shows a loss of 6 psi per 100 ft at the design flow. How much pressure is lost to friction over the full run?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với Master Plumber Licensing Exam (UPC/IPC-based) · Quy trình kiểm tra