Vertical in-line pumps

High water-content fluids are used in some hydrauhc systems where work-stroke speeds are very low, eg, large freight elevators and large forging and extmsion presses. Pressures in these systems may be from 13.8—20.7 MPa (2000—3000 psi). Vertical in-line pumps with packed plungers and special axial—piston pumps are used with these fluids. 

Figure 3-3. Cross-sectional view of a vertical in-line pump. (By permission, H. Knoll and S. Tinney, Hydrocarbon Processing," May 1971, p. 131 and Goulds Pump, Inc. Mechanical seal and seal venting details courtesy Borg-Warner.)...

Figure 2-2—Coordinate System for the Forces and Moments in Table 2.1 A (2.1 B) Vertical In-Line Pumps...

Vertical in-line pumps that are supported only by the attached piping may be subjected to component piping loads that are more than double the values shown in Table 2. lA (2. IB) if these loads do not cause a principal stress greater than 41 MPa (5950 psi) in either nozzle. For calculation purposes, the section properties of the pump nozzles shall be based on Schedule 40 pipe whose nominal size is equal to that of the appropriate pump nozzle. Equations F-6A (F-6B), F-7A (F-7B), and F-8A (F-8B) can be used to evaluate principal stress, longitudinal stress, and shear stress, respectively, in the nozzles. 

For an 80 X 100 x 178 vertical in-line pump, the proposed applied nozzle loadings are as given in Table F-3A. By in-... 

For a 3 X 4 X 7 vertical in-line pump, the proposed applied nozzle loadings are as given in Table F-3B. By inspection, FZ5a, AZZ5a, and MXDp are greater than two times the values shown in Table 2. IB. As stated in F.2, these component loads are acceptable provided that the calculated principal stress is less than 5950 psi. The problem is to determine the principal stress for the suction nozzle and the discharge nozzle. 

Shall vertical in-line pumps be designed for bolhng to a pad or foundation Yes No... 

The horizontal pumps are available for capacities up to 900 m /h (4000 gahmin) the vertical in-line pumps, for capacities up to 320 m /h (1400 gahmin). Both horizontal and vertical in-line pumps are available for heads up to 120 m (400 ft). The intent of each ANSI specification is that pumps from all vendors for a given nominal capacity and total dynamic head at a given rotative speed shall be dimensionally interchangeable with respect to mounting, size, and location of suction and discharge nozzles, input shaft, base plate, and foundation bolts. 

The vertical in-line pumps, although relatively new additions, are finding considerable use in chemical and petrochemical plants in the United States. An inspection of the two designs will m e clear the relative advantages and disadvantages of each. 

Unless otherwise specified, the datum elevation shall be the shaft centreline for horizontal pumps, the suction nozzle centreline for vertical in-line pumps, and the top of the foundation for vertically-suspended pumps. 

Allowable forces and moments for vertical in-line pumps shall be twice the values in Table 4 for side nozzles. 

FIG. 10-37b Vertical in-line process pump conforming to ANSI Standard B73.2-1975. The pump shown is driven by a motor through flexible coupling. Not shown but also conforming to ANSI Standard B73.2 are vertical in-line pumps with rigid couplings and with no coupling (impeller-mounted on an extended motor shaft). 

---