EXPERIENCE

IN A S S I M I L A T I N G

STANDARDIZED MACHINES

CENTRIFUGAL

IN T H E

A. M . G a l e e v

KAZAN' and

V.

PRODUCTION

OF

COMPRESSOR

COMPRESSOR

PLANT

B. S h n e p p

UDC 621.515.002.2

The Kazan' C o m p r e s s o r Plant has gone into the m a s s production of s t a n d a r d i z e d centrifugal c o m p r e s s o r m a c h i n e s [1] developed by the S p e c i a l Construction Office for C o m p r e s s o r Building (SKBK, Kazan'). The building of standardized centrifugal c o m p r e s s o r m a c h i n e s and putting them into production was p r e ceded by a complex of work which can a r b i t r a r i l y be divided into four stages. In the f i r s t stage, the main functional a g g r e g a t e s and s u b a s s e m b l i e s of centrifugal m a c h i n e s were d e t e r mined: the c o m p r e s s i o n housing, the g e a r - t y p e b o o s t e r s , the gas and oil c o o l e r s , the b e a r i n g s , the torsion clutches, the lubricating and packing s y s t e m , the automation s y s t e m , etc., the d e t e r m i n a t i o n of their p a r a m e t r i c o r d e r and development of the actual typical constructions. In the second stage, e x p e r i m e n t a l s a m p l e s of typical r e p r e s e n t a t i v e s of the functional a g g r e g a t e s and suba s s e m b l i e s of t h e i r determining e l e m e n t s were p r e p a r e d and subjected to exhaustive t e s t s . The principle of g e o m e t r i c similitude of the constructions made it possible to extend the c h a r a c t e r i s t i c s obtained to the r e m a i n hug standard t y p e s of s u b a s s e m b l i e s and a g g r e g a t e s . F o r e x a m p l e , as a r e s u l t of the testing of I6 typical s t a g e s of c o m p r e s s i o n housings, the c h a r a c t e r i s t i c s of the stages of the r e m a i n i n g 64 standard types w e r e d e t e r m i n e d , which c o n s i d e r a b l y reduced the volume and time of the e x p e r i m e n t a l work. In the third stage, in the SKBK a s y s t e m of p r o g r a m s and s u b p r o g r a m s was set up e m b r a c i n g the whole p r o c e s s of machine development. The calculation r e s u l t s , printed out by the c o m p u t e r , a r e included in the c a l c u l a t i o n a l - e x p l a n a t o r y d e s c r i p t i o n without any additional analysis or r e f o r m a t i o n . T h e s e p r o g r a m s c o n s i s t of complex engineering calculations, including the following operations: the use of n o m o g r a m s to select s e v e r a l competing s c h e m e s of the future s c h e m e s ; the use of an ES-1020 c o m p u t e r in a c c o r d a n c e with a given p r o g r a m for selection of the nominal (calculated) p a r a m e t e r s optimal for each scheme of the flow-through p a r t on the b a s i s of the c h a r a c t e r i s t i c s of s t a n d a r d s e t s of stages and g a s c o o l e r s stored in the m e m o r y ; selection of the best scheme of the machine for a given o r d e r on the b a s i s of an economic c o m p a r i s o n ; determination, in a c c o r d a n c e with a p r o g r a m , of the actual head - m a s s - f l o w - r a t e dependence and the l i m i t s of stable work of the c o m p r e s s o r , d i s c l o s u r e of the stage worsening the o v e r a l l c h a r a c t e r i s t i c of the machine, and its r e p l a c e m e n t ; determination, in accordance with specialized p r o g r a m s , of the axial f o r c e s , the c r i t i c a l f r e q u e n c i e s of the t r a n s v e r s e and t o r s i o n a l vibrations of the r o t o r s connected by g e a r - t y p e clutches, the friction l o s s e s in the b e a r i n g s and seals, and other p a r a m e t e r s . The SKBK is c a r r y i n g out work on the total automation of the design of standardized centrifugal c o m p r e s sor m a c h i n e s , including the c o m p u t e r specification and design of a m i n i m a l number of constituent p a r t s . In the fourth stage, work was s t a r t e d and continued on the development of the a g g r e g a t e s entering into the s y s t e m of standardized centrifugal c o m p r e s s o r machines, their p r e p a r a t i o n , and the equipment for their p r o duction. This work is b a s e d on p r e v i o u s l y planned constructional standardization, making it possible to c r e a t e typical technological p r o c e s s e s and equipment, to c o n s i d e r a b l y shorten the f a b r i c a t i o n times, and to improve the quality of the m a c h i n e s . The m o s t complex technical p r o b l e m was the building of a standard s e r i e s of c o m p r e s s i o n housings. The solution of this p r o b l e m s e r v e d as the s t a r t of a s y s t e m a t i c approach to the production of standardized c e n t r i fugal c o m p r e s s o r machines. T r a n s l a t e d f r o m Khimicheskoe i Neftyanoe Mashinostroenie, No. 1, pp. 5-7, J a n u a r y , 1978.

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0009-2355/78/0102-0010507.50

9 1978 Plenum Publishing C o r p o r a t i o n

With the construction of the cylinders of standardized centrifugal c o m p r e s s o r machines, account was taken of experience in the operation of machines with diffusor helixes cast in the housing. To the end of an i n c r e a s e in the rigidity of the cylinders, the bearing journals are brought out of the c h a m b e r s to the flange of a horizontal joint, as a r e s u l t of which c a s e s of uncentering of the c o m p r e s s o r s during the p r o c e s s of operation are eliminated. Actual s t r a i n - g a g e m e a s u r e m e n t of the cylinders made it possible to bring out their safety factor and to r a i s e the p e r m i s s i b l e working p r e s s u r e . During the p r o c e s s of the r e construction of the casting line, there was a considerable increase in the degree of mechanization of all the operations of the casting of the cylinders of standardized centrifugal c o m p r e s s o r machines (the l a r g e s t parts in the nomenclature of the plant) f r o m sand p r e p a r a t i o n to the e l e c t r o h y d r a u l i c knocking-out of the billets. The construction of the flow-through part of standardized centrifugal c o m p r e s s o r machines, in spite of the high degree of standardization, a s s u r e s a high efficiency of the c o m p r e s s i o n of various g a s e s . It must be noted that the transition to the production of standardized centrifugal c o m p r e s s o r machines coincided with the introduction of m o r e efficient, but m o r e complicated, flow-through parts, which permitted a 3-5% increase inthe efficiency of the c o m p r e s s o r machines, and brought them to a high technical level. In collaboration with the M. I. Kalinin Leningrad Polytechnic Institute (LPI) work is going f o r w a r d on the building of the flow-through part of a second generation of standardized centrifugal c o m p r e s s o r machines, based on a comparative evaluation of the losses of head using a calculation of a t h r e e - d i m e n s i o n a l boundary layer, taking account of secondary flows in a c c o r d a n c e with a method and a p r o g r a m developed at LPI. As the r e s u l t of the introduction of vacuum welding of working wheels of steel 09Khl5N8Yu, proposed by the All- Union S c i e n t i f i c - R e s e a r c h Institute of C o m p r e s s o r Machinery, the strength c h a r a c t e r i s t i c s of the wheels were raised, which made it possible to d e c r e a s e the thickness of the blades by 1.5 t i m e s and to increase the working velocities up to 320 m / s e c . In the plant, two vacuum furnaces are in operation for the welding of wheels with a diameter up to 480 m m and a furnace is being built for the welding of wheels with a diameter up to 640 mm. P a r t i c u l a r attention is being paid to increasing the reliability of c o m p r e s s o r machines f r o m the point of view of assuring the vibrational stability of r o t o r s working at speeds of 16,000 r p m or m o r e , as well as the strength of elements of machines with l o n g - t e r m operation. In this direction the SKBK and the Kazan' Comp r e s s o r Plant have c a r r i e d out work including a computer method for calculating c r i t i c a l conditions of r o t o r s rotating in sliding bearings; the introduction of s t a g e - b y - s t a g e balancing of flexible r o t o r s in r e s o n a n c e balancing stands with a magnetic f r a m e (according to an SKBK method), and static balancing of wheels on an air c u s h ion (in accordance with a method of the Kazan' Institute of Chemical Engineering); the introduction of a new e n t e r p r i s e standard for h i g h - p r e c i s i o n g e a r - t y p e clutches with gapless centering around the r i m of the g e a r ; a complex of apparatus has been built for monitoring the vibrational state of the machines by a contactless method during the tests. Traditional cylindrical or "lemon" bearings have been found unsuitable for standardized centrifugal c o m p r e s s o r machines as not a s s u r i n g the stability of the shaft journal in a wide range of conditions. The SKBK, on the level of the e n t e r p r i s e standard, has developed, investigated, and introduced five-wedge sliding thrust b e a r ings, a special c h a r a c t e r i s t i c of which is the p r e s e n c e of s y m m e t r i c a l (reverse) shoes, with a t e m p e r a t u r e oil wedge {Fig. 1). Such bearings work stably at any given r a t e s of rotation, as well as in conjunction with s m a l l gap slit-type seals. To r a i s e the quality and to improve the s t r u c t u r e of the babbitt layer of the shoes, the unit for the centrifugal lining of the bearings is provided with a p r a c t i c a l cooling s y s t e m and the optimal volume of the melt of babbitt for one batch of bearings is determined. W o r k i s b e i n g d o n e o a r e i n f o r c e m e a t o f t h e b a b b i t layer. As a r e s u l t of a complex of work done on i m p r o v e m e n t of the elements of the r o t o r - b e a r i n g system, the efficiency of machines put out after 1975 has i n c r e a s e d substantially. To increase the wear r e s i s t a n c e of the p a r t s of oil slit-type seals in standardized centrifugal c o m p r e s s o r s designed for the c o m p r e s s i o n of poisonous and explosive gases, experimental work is being done on implementation of the method of the p l a s m a - s p r a y deposition of a h a r d - a l l o y powder SNGN-50 on the surfaces of the necks of the r o t o r . The friation pair SNGN-50--babbitt B-83 is outstanding for high wear r e s i s t a n c e . A complex of technical equipment for the p l a s m a spraying of m a s s - p r o d u c e d p a r t s is being built in the plant. The e n t e r p r i s e standard provides for the fabrication of gas c o o l e r s with water cooling of 8 standard types, instead of the old apparatus with 30 designations. The cooling s u r f a c e s of the gas c o o l e r s consist of efficient a l l - r o l l e d finned tubes, r e c o m m e n d e d in the investigations of the Leningrad S c i e n t i f i c - R e s e a r c h Institute of Chemical Machinery. The principal advantages of the new gas c o o l e r s are simplicity of construction

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Fig. I

Fig. 2

Fig. 1. Wedge-type sliding thrust b e a r i n g s . Fig. 2. Complex of s t a n d a r d i z e d centrifugal c o m p r e s s i o n m a c h i n e s in the line of a c h e m i c a l c o m bine. (there a r e only two joints), technological f e a s i b i l i t y in construction, r e l i a b i l i t y and convenience in operation, and the possibility of c a r r y i n g out both m e c h a n i c a l and c h e m i c a l cleaning of the tube space. The g a s c o o l e r s can be installed in either a horizontal or v e r t i c a l position, which p r o m o t e s a logical a s s e m b l y of the c o m p r e s sor units. The use of heat-exchange tubes, in all the g a s c o o l e r s , f a b r i c a t e d in a special machine designed by the All-Union S c i e n t i f i c - R e s e a r c h Institute of M e t a l l u r g i c a l M a c h i n e r y , has made it possible to well equip, automate, and organize the continuous production of g a s c o o l e r s in a s p e c i a l i z e d section, whose r e c o n s t r u c t i o n will be completed in 1977. With the s t a r t of the production of s t a n d a r d i z e d centrifugal c o m p r e s s o r m a c h i n e s , t h e r e has been a cons i d e r a b l e reduction in the number of pieces of equipment in production. F o r example, the s e r i e s of c o m p r e s sion housings has only 16 standard t y p e s of working wheels, for whose f a b r i c a t i o n 180 items of equipment a r e r e q u i r e d . If the production of c o m p r e s s o r s w e r e to be c a r r i e d out in a c c o r d a n c e with individual p r o j e c t s , for the f a b r i c a t i o n of the working wheels for 13 m a c h i n e s 1520 items of equipment would be r e q u i r e d . In all, on the b a s i s of s t a n d a r d i z e d centrifugal m a c h i n e s , 33 c o m p r e s s o r s of nine designations a r e being put out, designed for the c o m p r e s s i o n of eight different g a s e s . Figure 2 shows a complex of s t a n d a r d i z e d c e n trifugal c o m p r e s s i o n m a c h i n e s installed in the line of a c h e m i c a l combine. Thanks to a s y s t e m a t i c approach to the building of s t a n d a r d i z e d centrifugal c o m p r e s s o r m a c h i n e s an o v e r a l l saving of m o r e than 8 million r u b i e s has been effected. T h e r e has been a considerable reduction in the t i m e r e q u i r e d to put the new c o m p r e s s o r s into production. F o r example, the c o m p r e s s o r 5 T s K K - 2 1 6 / 1 . 0 5 - 5 for the c o m p r e s s i o n of divinyl (capacity 216 m~/min, p r e s s u r e 5 kg/cm2), built on the b a s i s of standardized centrifugal c o m p r e s s o r m a c h i n e s , was put into operation t h r e e y e a r s after the o r d e r was issued, while an analogous hydrogen sulfide c o m p r e s s o r , built in a c c o r d a n c e with an individual project, w a s put into o p e r a t i o n six y e a r s a f t e r the o r d e r w a s issued. T h e r e has been a r i s e of 1.5-1.8 t i m e s in the r e l i a b i l i t y of the c o m p r e s s o r s as the r e s u l t of the s y s t e m a t i c d i r e c t e d finishing of their standard working s u b a s s e m b l i e s . The p r e v i o u s l y planned high d e g r e e of standardization of the constructions (up to 90%) m a k e s it possible to set up the " a d d r e s s - f r e e fabrication" of the m o s t l a b o r - c o n s u m i n g p a r t s . An automatic control s y s t e m using an e l e c t r o n i c c o m p u t e r has been developed in the plant f o r operational control of production. The r e a l possibility has a p p e a r e d of shortening the e r e c t i o n t i m e s of the m a c h i n e s at the points of use due to a standardization of communications and an i n c r e a s e in the d e g r e e of plant finishing (the block system} of the standardized a g g r e g a t e s , which, a f t e r plant t e s t s , a r e sealed and do not need to be opened and inspected with e r e c t i o n . The production of a s e r i e s of standardized a g g r e g a t e s has m a d e it possible to build s t a n d a r d i z e d c e n t r i fugal c o m p r e s s o r m a c h i n e s with a capacity up to 400 mS/rain at a p r e s s u r e up to 40 k g / e m ~. Using a housing with a v e r t i c a l joint, m a c h i n e s can be built for higher p r e s s u r e s . As an e x a m p l e , Fig. 3 shows the s c h e m e of the a s s e m b l y of a p r o p o s e d c o m p r e s s o r for pumping g a s into o i l - b e a r i n g s t r a t a (gas lift}, with a capacity for suction conditions of 110 mS/min at a p r e s s u r e of 120 k g / e m 2. 12

J

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I

a) 4

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Z

Z

I

Fig. 3

Fig. 4

Fig. 3. Scheme of the a s s e m b l y of a c o m p r e s s o r for the pumping of g a s into an o i l - b e a r i n g s t r a t u m with a c a p a c i t y of 110 m 3 / m i n at a p r e s s u r e of 120 kg/cm2: 1) basic housing of s t a n d a r d i z e d cemtrifugal c o m p r e s s o r m a c h i n e No. 3 with horizontal joint; 2) b a s i c housing No. 2 f o r high p r e s s u r e with a v e r t i c a l joint. Fig. 4. A s s e m b l y s c h e m e s of the 654TsKK-550/40 (a) and 85TsK-2000/40 (b) oxygen c o m p r e s s o r s with c a p a c i t i e s of 550 and 2000 m3/min, r e s p e c t i v e l y , at a p r e s s u r e of 40 kg/cm2: 1, 2, 3, 4) basic housings of s t a n d a r d i z e d centrifugal c o m p r e s s o r m a c h i n e s Nos. 4, 5, 6, and 8, r e s p e c t i v e l y , with a horizontal joint. The r a n g e of the c a p a c i t i e s of s t a n d a r d i z e d centrifugal c o m p r e s s o r s is still limited, which is due to t e c h nical p o s s i b i l i t i e s of the existing plant m a c h i n e r y a n d lifting equipment. It is d e s i r a b l e to expand the s e r i e s of c o m p r e s s o r s toward the side of g r e a t e r c a p a c i t i e s . After putting into production basic housings with wheels with a d i a m e t e r of 750, 950, and 1200 ram, r e s p e c t i v e l y , it will b e c o m e possible to put out s t a n d a r d i z e d c e n t r i fugal c o m p r e s s o r m a c h i n e s with a capacity up to 1800 m3/min. Figure 4 g i v e s e x a m p l e s of the a s s e m b l y of c o m p r e s s o r s on the b a s i s of these housings. In the n e a r future, it is planned to r e p l a c e a m a j o r i t y of obsolete individual t u r b o m a c h i n e s by new, m o d e r n ones, built on the b a s i s of s t a n d a r d i z e d centrifugal c o m p r e s s o r machineS. The introduction of a testing station, unique in its possibilities, will p e r m i t the Kazan' c o m p r e s s o r builders to c o n s i d e r a b l y r a i s e the quality of their product;. LITERATURE 1.

CITED

V. V. Shnepp, A. K. Suvorov, S. V. T s u k e r m a n , et al., "Standardized centrifugal c o m p r e s s o r s , " Khim. Neft. M a s h i n o s t r . , No. 6, 27-29 (1972).

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